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Aluminum electrolytic capacitor _ Wikipedia audio article
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00:00:00.620 aluminum electrolytic capacitors are 00:00:03.40900:00:03.419 polarized electrolytic capacitors whose 00:00:05.93000:00:05.940 anode electrode Plus is made of a pure 00:00:08.62900:00:08.639 aluminum foil with an etched surface the 00:00:11.90000:00:11.910 aluminum forms a very thin insulating 00:00:14.41900:00:14.429 layer of aluminium oxide by anodization 00:00:16.70000:00:16.710 that acts as the dielectric of the 00:00:19.07000:00:19.080 capacitor a non solid electrolyte covers 00:00:22.64000:00:22.650 the rough surface of the oxide layer 00:00:24.34000:00:24.350 serving in principle as the second 00:00:26.90000:00:26.910 electrode cathode of the capacitor a 00:00:29.76900:00:29.779 second aluminum foil called cathode foil 00:00:33.08000:00:33.090 contacts the electrolyte and serves as 00:00:35.54000:00:35.550 the electrical connection to the 00:00:37.19000:00:37.200 negative terminal of the capacitor 00:00:39.88000:00:39.89000:00:42.61900:00:42.629 divided into three sub families by the 00:00:44.84000:00:44.850 type of electrolyte non solid liquid wet 00:00:48.97900:00:48.989 aluminum electrolytic capacitors solid 00:00:53.06000:00:53.070 manganese dioxide aluminum electrolytic 00:00:55.42000:00:55.430 capacitors and solid polymer aluminium 00:00:59.47900:00:59.489 electrolytic capacitors aluminum 00:01:01.76000:01:01.770 electrolytic capacitors with non solid 00:01:04.16000:01:04.170 electrolytes are the most inexpensive 00:01:05.92900:01:05.939 type and also those with widest range of 00:01:08.75000:01:08.760 sizes capacitance and voltage values 00:01:11.64900:01:11.659 they are made with capacitance values 00:01:14.60000:01:14.610 from 0.1 micro farad's up to 2 million 00:01:18.05000:01:18.060 700 thousand microfarads 2.7 F and rated 00:01:22.91000:01:22.920 voltages values from 4 volts up to 630 V 00:01:26.69000:01:26.700 the liquid electrolyte provides oxygen 00:01:28.76000:01:28.770 for reforming or self-healing of the 00:01:31.28000:01:31.290 dielectric oxide layer however it can 00:01:34.85000:01:34.860 evaporate through a temperature 00:01:36.49900:01:36.509 dependent drying out process which 00:01:38.74900:01:38.759 causes electrical parameters to drift 00:01:41.09000:01:41.100 limiting the service lifetime of the 00:01:43.39900:01:43.409 capacitors due to their relatively high 00:01:46.96900:01:46.979 capacitance values aluminium 00:01:49.03900:01:49.049 electrolytic capacitors have low 00:01:51.08000:01:51.090 impedance values even at lower 00:01:53.06000:01:53.070 frequencies like mains frequency they 00:01:56.53900:01:56.549 are typically used in power supplies 00:01:58.56900:01:58.579 switched-mode power supplies and DC DC 00:02:01.73000:02:01.740 converters for smoothing and buffering 00:02:04.10000:02:04.110 rectified DC voltages in many electronic 00:02:07.19000:02:07.200 devices as well as in industrial power 00:02:09.46900:02:09.479 supplies and frequency converters as DC 00:02:12.41000:02:12.420 link 00:02:12.96000:02:12.970 Tacitus for drives inverters for 00:02:14.97000:02:14.980 photovoltaic and converters in wind 00:02:17.55000:02:17.560 power plants special types are used for 00:02:21.27000:02:21.280 energy storage for example in photo 00:02:23.64000:02:23.650 flash or strobe applications or for 00:02:26.16000:02:26.170 frequency coupling in audio applications 00:02:29.69000:02:29.70000:02:32.46000:02:32.470 polarized capacitors because of their 00:02:34.65000:02:34.660 anodization principle they can only be 00:02:37.47000:02:37.480 operated with DC voltage applied with 00:02:40.14000:02:40.150 the correct polarity operating the 00:02:43.14000:02:43.150 capacitor with wrong polarity or with AC 00:02:45.48000:02:45.490 voltage leads to a short circuit and can 00:02:48.27000:02:48.280 destroy the component the exceptions is 00:02:51.78000:02:51.790 the bipolar aluminum electrolytic 00:02:53.61000:02:53.620 capacitor which has a back-to-back 00:02:55.98000:02:55.990 configuration of two anodes in one case 00:02:58.53000:02:58.540 and can be used in AC applications 00:03:06.35000:03:06.360 topic basic information 00:03:12.66000:03:12.670 you 00:03:16.19000:03:16.200 topic oxide layer 00:03:21.91000:03:21.920 electrolytic capacitors use a chemical 00:03:24.61900:03:24.629 feature of some special metals earlier 00:03:27.28900:03:27.299 called valve metals applying a positive 00:03:31.10000:03:31.110 voltage to the anode material in an 00:03:33.64900:03:33.659 electrolytic bath forms an insulating 00:03:36.19900:03:36.209 oxide layer with a thickness 00:03:37.66000:03:37.670 corresponding to the applied voltage 00:03:40.08900:03:40.099 this oxide layer acts as the dielectric 00:03:43.52000:03:43.530 in an electrolytic capacitor the 00:03:45.86000:03:45.870 properties of this aluminum oxide layer 00:03:48.17000:03:48.180 compared with tantalum pentoxide 00:03:50.39000:03:50.400 dielectric layer are given in the 00:03:52.28000:03:52.290 following table after forming a 00:03:55.30900:03:55.319 dielectric oxide on the rough anode 00:03:57.53000:03:57.540 structures a counter electrode has to 00:04:00.02000:04:00.030 match the rough insulating oxide surface 00:04:02.68000:04:02.690 this is provided by the electrolyte 00:04:05.56900:04:05.579 which acts as the cathode electrode of 00:04:07.94000:04:07.950 an electrolytic capacitor electrolytes 00:04:11.11900:04:11.129 may be non solid wet liquid or solid non 00:04:17.24000:04:17.250 solid electrolytes as a liquid medium 00:04:19.96900:04:19.979 that has an ion conductivity caused by 00:04:22.49000:04:22.500 moving ions a relatively insensitive to 00:04:25.04000:04:25.050 voltage spikes or current surges solid 00:04:28.85000:04:28.860 electrolytes have an electron 00:04:30.58900:04:30.599 conductivity which makes solid 00:04:32.81000:04:32.820 electrolytic capacitors sensitive to 00:04:35.18000:04:35.190 voltages spikes or current surges the 00:04:38.90000:04:38.910 anodic generated insulating oxide layer 00:04:41.62900:04:41.639 is destroyed if the polarity of the 00:04:43.73000:04:43.740 applied voltage changes every 00:04:46.96900:04:46.979 electrolytic capacitor in principle 00:04:49.33900:04:49.349 forms a plate capacitor whose 00:04:52.37000:04:52.380 capacitance is greater the larger the 00:04:54.68000:04:54.690 electrode area a and the permittivity 00:04:56.71900:04:56.729 epsilon and the thinner the thickness D 00:04:59.15000:04:59.160 of the dielectric 00:05:01.02900:05:01.039 see 00:05:03.17000:05:03.180 equals epsilon a D display style C 00:05:11.12000:05:11.130 equals ver epsilon C do t frac a D 00:05:16.06000:05:16.070 the capacitance is proportional to the 00:05:18.19000:05:18.200 product of the area of one plate 00:05:19.96000:05:19.970 multiplied with the permittivity divided 00:05:22.63000:05:22.640 by the thickness of the dielectric 00:05:25.50000:05:25.510 electrolytic capacitors obtain their 00:05:28.03000:05:28.040 large capacitance values by a large area 00:05:30.85000:05:30.860 and small dielectric thickness the 00:05:33.88000:05:33.890 dielectric thickness of electrolytic 00:05:36.04000:05:36.050 capacitors is very thin in the range of 00:05:38.62000:05:38.630 nanometers per volt but the voltage 00:05:40.75000:05:40.760 strengths of these oxide layers are 00:05:43.00000:05:43.010 quite high all let's tour sintered 00:05:45.82000:05:45.830 anodes have a much higher surface 00:05:47.59000:05:47.600 compared to a smooth surface of the same 00:05:50.11000:05:50.120 area this increases the capacitance 00:05:53.23000:05:53.240 value by a factor of up to 200 for 00:05:56.02000:05:56.030 aluminum electrolytic capacitors 00:06:03.30000:06:03.310 topic construction of non solid aluminum 00:06:07.11000:06:07.120 electrolytic capacitors 00:06:12.36000:06:12.370 basic construction of aluminum 00:06:14.76000:06:14.77000:06:17.18900:06:17.199 electrolytes an aluminum electrolytic 00:06:20.40000:06:20.410 capacitor with a non solid electrolyte 00:06:23.01000:06:23.020 always consists of two aluminum foils 00:06:25.62000:06:25.630 separated mechanically by a spacer 00:06:27.75000:06:27.760 mostly paper which is saturated with a 00:06:30.54000:06:30.550 liquid or gel like electrolyte one of 00:06:33.75000:06:33.760 the aluminum foils the anode is etched 00:06:36.33000:06:36.340 roughen to increase the surface and 00:06:38.55000:06:38.560 oxidized formed the second aluminum foil 00:06:42.21000:06:42.220 called the cathode foil serves to make 00:06:45.99000:06:46.000 electrical contact with the electrolyte 00:06:48.18000:06:48.190 a paper spacer mechanically separates 00:06:51.30000:06:51.310 the foils to avoid direct metallic 00:06:53.73000:06:53.740 contact both foils in the space are 00:06:57.06000:06:57.070 wound and the winding is impregnated 00:06:59.01000:06:59.020 with liquid electrolytes the electrolyte 00:07:02.40000:07:02.410 which serves as cathode of the capacitor 00:07:04.92000:07:04.930 covers the etched rough structure of the 00:07:06.90000:07:06.910 oxide layer on the anode perfectly and 00:07:09.30000:07:09.310 makes the increased anode surface 00:07:10.98000:07:10.990 effectual after impregnation the 00:07:14.25000:07:14.260 impregnated winding is mounted in an 00:07:16.50000:07:16.510 aluminum case and sealed by design a non 00:07:20.70000:07:20.710 solid aluminum electrolytic capacitor 00:07:23.19000:07:23.200 has a second aluminum foil the so called 00:07:25.92000:07:25.930 cathode foil for contacting the 00:07:27.96000:07:27.970 electrolyte this structure of an 00:07:30.71900:07:30.729 aluminum electrolytic capacitor results 00:07:33.27000:07:33.280 in a characteristic result because the 00:07:35.49000:07:35.500 second aluminum cathode foil is also 00:07:37.92000:07:37.930 covered with an insulating oxide layer 00:07:40.02000:07:40.030 naturally formed by air therefore the 00:07:43.40900:07:43.419 construction of the electrolytic 00:07:45.21000:07:45.220 capacitor consists of two single series 00:07:47.94000:07:47.950 connected capacitors with capacitance CA 00:07:50.61000:07:50.620 of the anode and capacitance CK of the 00:07:53.25000:07:53.260 cathode the total capacitance of the 00:07:56.40000:07:56.410 capacitor C II cap is thus obtained from 00:07:59.01000:07:59.020 the formula of the series connection of 00:08:01.11000:08:01.120 two capacitors C II minus 00:08:08.15900:08:08.169 see a P equals C 00:08:16.07000:08:16.080 a c k c a+ c k display style c 00:08:30.64900:08:30.659 underscore ECAP equals pract c 00:08:33.17000:08:33.180 underscore @ çd OTC underscore kate c 00:08:36.98000:08:36.990 underscore a plus c underscore k it 00:08:40.67000:08:40.680 follows that the total capacitance of 00:08:43.06900:08:43.079 the capacitor c cap is mainly determined 00:08:45.41000:08:45.420 by the anode capacitance CA when the 00:08:48.31900:08:48.329 cathode capacitance c k is very large 00:08:51.01900:08:51.029 compared with the anode capacitance CA 00:08:53.86000:08:53.870 this requirement is given when the 00:08:56.66000:08:56.670 cathode capacitance CK is approximately 00:08:59.56900:08:59.579 10 times higher than the anode 00:09:01.40000:09:01.410 capacitance CA this can be easily 00:09:04.61000:09:04.620 achieved because the natural oxide layer 00:09:07.10000:09:07.110 on a cathode surface has a voltage proof 00:09:09.68000:09:09.690 of approximately 1.5 volts and is 00:09:12.50000:09:12.510 therefore very thin 00:09:18.75000:09:18.760 topic comparison of non solid and solid 00:09:22.53000:09:22.540 types 00:09:26.64000:09:26.650 although the present article only refers 00:09:29.37000:09:29.380 in essence to aluminum electrolytic 00:09:31.28000:09:31.290 capacitors with non solid electrolyte an 00:09:34.20000:09:34.210 overview of the different types of 00:09:36.00000:09:36.010 aluminum electrolytic capacitors is 00:09:38.31000:09:38.320 given here in order to highlight the 00:09:40.14000:09:40.150 differences aluminum electrolytic 00:09:42.98000:09:42.990 capacitors are divided into two subtypes 00:09:45.90000:09:45.910 depending on whether they make use of 00:09:48.03000:09:48.040 liquid or solid electrolyte systems 00:09:50.84000:09:50.850 because the different electrolyte 00:09:53.10000:09:53.110 systems can be constructed with a 00:09:55.08000:09:55.090 variety of different materials they 00:09:57.39000:09:57.400 include further subtypes aluminum 00:10:01.08000:10:01.09000:10:03.57000:10:03.580 electrolyte may use a liquid electrolyte 00:10:06.69000:10:06.700 based on ethylene glycol and boric acid 00:10:09.54000:10:09.550 so-called borax electrolytes or based on 00:10:15.51000:10:15.520 organic solvents such as DMF d ma g BL 00:10:19.50000:10:19.510 or based on high water containing 00:10:22.92000:10:22.930 solvents for so-called low impedance low 00:10:27.33000:10:27.340 ESR or high ripple current capacitors 00:10:33.20000:10:33.210 aluminum electrolytic capacitors with 00:10:35.91000:10:35.920 solid electrolyte have a solid manganese 00:10:39.51000:10:39.520 dioxide electrolyte see solid aluminum 00:10:42.54000:10:42.550 capacitor Sall or a solid polymer 00:10:46.23000:10:46.240 electrolyte see polymer aluminum 00:10:48.60000:10:48.610 electrolytic capacitor or hybrid 00:10:52.08000:10:52.090 electrolytes with both a solid polymer 00:10:54.45000:10:54.460 and a liquid see also polymer aluminum 00:10:57.12000:10:57.130 electrolytic capacitor principle design 00:11:00.75000:11:00.760 differences of the different aluminum 00:11:02.82000:11:02.830 electrolytic capacitor subtypes 00:11:05.87000:11:05.880 description of the materials 00:11:08.99000:11:09.000 one anode foil to anode oxide layer 00:11:12.13000:11:12.140 dielectric three cathode foil four 00:11:15.38000:11:15.390 cathode oxide layer five non solid 00:11:18.56000:11:18.570 electrolytes six paper spacer soaked 00:11:21.44000:11:21.450 with electrolyte either non solid or 00:11:23.66000:11:23.670 polymer seven conducting polymer eight 00:11:26.30000:11:26.310 manganese oxide manganese four oxide 00:11:29.45000:11:29.460 nine graphite ten Sylva following table 00:11:33.17000:11:33.180 shows an overview over the main 00:11:34.81000:11:34.820 characteristics of the different types 00:11:36.83000:11:36.840 of aluminum electrolytic capacitors one 00:11:40.64000:11:40.650 values for a typical capacitor with 100 00:11:43.82000:11:43.830 microfarads 10 to 16 volts aluminium 00:11:48.08000:11:48.09000:11:50.48000:11:50.490 electrolyte are the best-known and most 00:11:52.34000:11:52.350 widely used electrolytic capacitors 00:11:55.03000:11:55.040 these components can be found on almost 00:11:58.22000:11:58.230 all boards of electronic equipment they 00:12:01.58000:12:01.590 are characterized by particularly 00:12:03.65000:12:03.660 inexpensive and easy to process base 00:12:06.08000:12:06.090 materials aluminum capacitors with 00:12:09.95000:12:09.960 liquid electrolytes based on borax or 00:12:12.47000:12:12.480 organic solvents have a large range of 00:12:14.93000:12:14.940 types and ratings capacitors with water 00:12:18.47000:12:18.480 based electrolytes are often found in 00:12:20.81000:12:20.820 digital devices for mass production 00:12:23.32000:12:23.330 types with solid manganese dioxide 00:12:26.20000:12:26.210 electrolytes have served in the past as 00:12:28.79000:12:28.800 a tantalum replacement polymer aluminium 00:12:32.87000:12:32.880 electrolytic capacitors with solid 00:12:35.09000:12:35.100 conductive polymer electrolytes are 00:12:37.16000:12:37.170 becoming increasingly important 00:12:38.96000:12:38.970 especially in devices with a flat design 00:12:41.66000:12:41.670 such as tablet PCs and flat panel 00:12:44.45000:12:44.460 displays electrolytic capacitors with 00:12:47.81000:12:47.820 hybrid electrolytes are relatively new 00:12:50.12000:12:50.130 on the market with their hybrid 00:12:52.22000:12:52.230 electrolyte system they combine the 00:12:54.62000:12:54.630 improved conductivity of the polymer 00:12:56.72000:12:56.730 with the advantage of liquid 00:12:58.28000:12:58.290 electrolytes for better self-healing 00:13:00.26000:13:00.270 property of the oxide layer so that the 00:13:02.75000:13:02.760 capacitors have the advantages of both 00:13:05.00000:13:05.010 low ESR and low leakage current 00:13:12.76000:13:12.770 topic materials 00:13:18.61000:13:18.62000:13:22.10000:13:22.110 topic anode 00:13:27.26000:13:27.270 the basic material of the anode for 00:13:29.63000:13:29.640 aluminum electrolytic capacitors is a 00:13:32.21000:13:32.220 foil with a thickness of approximately 00:13:34.37000:13:34.380 20 to 100 micrometers made of aluminum 00:13:37.57900:13:37.589 with a high purity of at least 99.99% 00:13:41.86000:13:41.870 this is etched roughened in an 00:13:44.38900:13:44.399 electrochemical process to increase the 00:13:46.61000:13:46.620 effective electrode surface by etching 00:13:49.85000:13:49.860 the surface of the anode depending on 00:13:52.28000:13:52.290 the required rated voltage the surface 00:13:54.76900:13:54.779 area can be increased by a factor of 00:13:56.87000:13:56.880 approximately 200 with respect to a 00:13:59.42000:13:59.430 smooth surface after etching the 00:14:01.43000:14:01.440 aluminum anode the rough surfaces anodic 00:14:04.49000:14:04.500 oxidized all formed an electrically 00:14:09.11000:14:09.120 insulating oxide layer aluminium oxide 00:14:11.90000:14:11.910 is thereby formed on the aluminum 00:14:13.91000:14:13.920 surface by application of a current in 00:14:16.40000:14:16.410 correct polarity if it is inserted in an 00:14:18.86000:14:18.870 electrolytic bath this oxide layer is 00:14:22.43000:14:22.440 the capacitor dielectric this process of 00:14:26.32900:14:26.339 oxide formation is carried out in two 00:14:28.91000:14:28.920 reaction steps whereby the oxygen for 00:14:31.51900:14:31.529 this reaction has to come from the 00:14:33.26000:14:33.270 electrolyte first a strongly exothermic 00:14:36.97000:14:36.980 reaction transforms the metallic 00:14:39.41000:14:39.420 aluminum owl into aluminum hydroxide 00:14:42.01000:14:42.020 aluminium hydroxide 2l plus 6 h2o to 00:14:47.21000:14:47.220 aluminium hydroxide plus 3 h2 this 00:14:50.56900:14:50.579 reaction is accelerated by a high 00:14:52.69900:14:52.709 electric field and high temperatures and 00:14:55.06900:14:55.079 is accompanied by a pressure buildup in 00:14:57.31900:14:57.329 the capacitor housing caused by the 00:14:59.18000:14:59.190 released hydrogen gas the gel like 00:15:02.32900:15:02.339 aluminum hydroxide aluminium hydroxide 00:15:04.94000:15:04.950 also called alumina trihydrate apps is 00:15:08.32900:15:08.339 converted via a second reaction step 00:15:10.94000:15:10.950 usually slowly over a few hours at room 00:15:13.55000:15:13.560 temperature more rapidly in a few 00:15:15.68000:15:15.690 minutes at higher temperatures Inter 00:15:17.81000:15:17.820 aluminium oxide 00:15:19.04000:15:19.050 aluminium oxide to aluminium hydroxide 00:15:22.73000:15:22.740 to a low OH + 2 h2o aluminium oxide plus 00:15:27.13900:15:27.149 3 H 2o the lumina mach side serves as 00:15:30.05000:15:30.060 dielectric and also protects the 00:15:32.09000:15:32.100 metallic aluminum against aggressive 00:15:33.92000:15:33.930 chemical reactions from the electrolyte 00:15:36.73000:15:36.740 however the converted layer of aluminium 00:15:39.86000:15:39.870 oxide is usually 00:15:41.21000:15:41.220 homogeneous it forms a complex 00:15:44.26900:15:44.279 multi-layer structured laminate of 00:15:46.51900:15:46.529 amorphous crystalline and porous 00:15:48.55900:15:48.569 crystalline aluminum oxide mostly 00:15:50.99000:15:51.000 covered with small residual parts of 00:15:53.11900:15:53.129 unconverted aluminum hydroxide for this 00:15:56.56900:15:56.579 reason in the formation of the anode 00:15:58.85000:15:58.860 foil the oxide film is structured by a 00:16:01.42900:16:01.439 special chemical treatment so that 00:16:03.37900:16:03.389 either an amorphous oxide or a 00:16:05.30000:16:05.310 crystalline oxide is formed the 00:16:08.11900:16:08.129 amorphous oxide variety yields higher 00:16:10.73000:16:10.740 mechanical and physical stability and 00:16:13.04000:16:13.050 fewer defects thus increasing the long 00:16:15.49900:16:15.509 term stability in lowering the leakage 00:16:17.72000:16:17.730 current amorphous oxide has a dielectric 00:16:21.59000:16:21.600 ratio of approximately 1.4 nano meters v 00:16:25.92900:16:25.939 compared to crystalline aluminum oxide 00:16:28.79000:16:28.800 which has a dielectric ratio of 00:16:31.04000:16:31.050 approximately 1.0 nanometers V the 00:16:34.22000:16:34.230 amorphous variety has a 40% lower 00:16:36.88900:16:36.899 capacitance at the same anode surface 00:16:39.49000:16:39.500 the disadvantage of crystalline oxide is 00:16:43.00900:16:43.019 its greater sensitivity to tensile 00:16:45.25900:16:45.269 stress which may lead to micro cracks 00:16:47.68900:16:47.699 when subjected to mechanical winding or 00:16:50.32900:16:50.339 thermal soldiering stressor during the 00:16:52.81900:16:52.829 post forming processes the various 00:16:56.21000:16:56.220 properties of oxide structures affect 00:16:58.61000:16:58.620 the subsequent characteristics of the 00:17:00.74000:17:00.750 electrolytic capacitors anode foils with 00:17:04.42900:17:04.439 amorphous oxide are primarily used for 00:17:06.82900:17:06.839 electrolytic capacitors with stable long 00:17:09.47000:17:09.480 life characteristics for capacitors with 00:17:12.19900:17:12.209 low leakage current values and 4e caps 00:17:14.87000:17:14.880 with rated voltages up to about 100 00:17:17.51000:17:17.520 volts capacitors with higher voltages 00:17:20.92900:17:20.939 for example photo flash capacitors 00:17:23.53900:17:23.549 usually containing anode foils with 00:17:26.05900:17:26.069 crystalline oxide because the thickness 00:17:28.15900:17:28.169 of the effective dielectric is 00:17:30.08000:17:30.090 proportional to the forming voltage the 00:17:32.45000:17:32.460 dielectric thickness can be tailored to 00:17:34.58000:17:34.590 the rated voltage of the capacitor for 00:17:37.58000:17:37.590 example for low voltage types a 10 volts 00:17:40.66900:17:40.679 electrolytic capacitor has a dielectric 00:17:42.91900:17:42.929 thickness of only about 0.01 4 00:17:46.13000:17:46.140 micrometers a 100 volts electrolytic 00:17:49.22000:17:49.230 capacitor of only about 0.14 micrometers 00:17:54.23000:17:54.240 the dielectric strength also influences 00:17:57.14000:17:57.150 the size of the capacitor 00:17:58.90000:17:58.910 however due to standardized safety 00:18:02.00000:18:02.010 margins the actual forming voltage of 00:18:04.46000:18:04.470 electrolytic capacitors is higher than 00:18:06.65000:18:06.660 the rated voltage of the component 00:18:10.27000:18:10.280 aluminum anode foils are manufactured as 00:18:13.43000:18:13.440 so-called mother rolls of about 500 00:18:17.63000:18:17.640 millimeters in width 00:18:19.10000:18:19.110 they are preformed for the desired rated 00:18:21.71000:18:21.720 voltage and with the desired oxide layer 00:18:23.96000:18:23.970 structure to produce the capacitors the 00:18:27.47000:18:27.480 anode widths and lengths as required for 00:18:29.93000:18:29.940 a capacitor have to be cut from the 00:18:32.00000:18:32.010 mother role 00:18:37.72000:18:37.730 topic cathode 00:18:43.01000:18:43.020 the second aluminium foil in the 00:18:45.38000:18:45.390 electrolytic capacitor called the 00:18:47.51000:18:47.520 cathode foil serves to make electrical 00:18:51.23000:18:51.240 contact with the electrolyte this foil 00:18:54.08000:18:54.090 has a somewhat lower degree of purity 00:18:56.26900:18:56.279 about ninety-nine point eight percent it 00:18:59.75000:18:59.760 is always provided with a very thin 00:19:02.02900:19:02.039 oxide layer which arises from the 00:19:04.25000:19:04.260 contact of the aluminum surface with the 00:19:06.52900:19:06.539 air in a natural way in order to reduce 00:19:09.71000:19:09.720 the contact resistance to the 00:19:11.48000:19:11.490 electrolyte and to make it difficult for 00:19:13.54900:19:13.559 oxide formation during discharging the 00:19:16.37000:19:16.380 cathode foil is alloyed with metals such 00:19:18.83000:19:18.840 as copper silicon or titanium the 00:19:21.85000:19:21.860 cathode foil is also etched to enlarge 00:19:24.68000:19:24.690 the surface because of the extremely 00:19:28.13000:19:28.140 thin oxide layer which corresponds to a 00:19:30.86000:19:30.870 voltage proof of about 1.5 volts their 00:19:34.03900:19:34.049 specific capacitance is however much 00:19:36.64900:19:36.659 higher than that of anode foils to 00:19:39.68000:19:39.690 justify the need for a large surface 00:19:41.84000:19:41.850 capacitance of the cathode foil see the 00:19:44.57000:19:44.580 section on charge discharge stability 00:19:46.88000:19:46.890 below the cathode foils as the anode 00:19:50.65900:19:50.669 foils are manufactured as so-called 00:19:52.76000:19:52.770 mother rolls from which widths and 00:19:56.36000:19:56.370 lengths are cut off as required for 00:19:58.63900:19:58.649 capacitor production 00:20:01.66000:20:01.67000:20:05.09000:20:05.100 topic electrolytes 00:20:10.69000:20:10.700 the electrolytic capacitor got its name 00:20:13.51000:20:13.520 from the electrolyte the conductive 00:20:15.61000:20:15.620 liquid inside the capacitor as a liquid 00:20:19.00000:20:19.010 it can be adapted to the porous 00:20:20.77000:20:20.780 structure of the anode and the grown 00:20:22.48000:20:22.490 oxide layer with the same shape and form 00:20:24.97000:20:24.980 as a tailor-made cathode an electrolyte 00:20:29.02000:20:29.030 always consists of a mixture of solvents 00:20:31.66000:20:31.670 and additives to meet given requirements 00:20:34.17000:20:34.180 the main electrical property of the 00:20:36.94000:20:36.950 electrolyte is its conductivity which is 00:20:39.43000:20:39.440 physically an ion conductivity in 00:20:41.74000:20:41.750 liquids in addition to the good 00:20:44.47000:20:44.480 conductivity of operating electrolytes 00:20:46.84000:20:46.850 various other requirements are among 00:20:49.33000:20:49.340 other things chemical stability high 00:20:51.91000:20:51.920 flashpoint chemical compatibility with 00:20:54.67000:20:54.680 aluminum low viscosity low environmental 00:20:57.22000:20:57.230 impact and low costs the electrolyte 00:21:01.00000:21:01.010 should also provide oxygen for forming 00:21:03.52000:21:03.530 and self-healing processes and all this 00:21:05.80000:21:05.810 within a temperature range as wide as 00:21:07.90000:21:07.910 possible this diversity of requirements 00:21:11.38000:21:11.390 for the liquid electrolyte results in a 00:21:13.51000:21:13.520 wide variety of proprietary solutions 00:21:16.00000:21:16.010 the electrolytic systems used today can 00:21:18.82000:21:18.830 be roughly summarized into three main 00:21:20.92000:21:20.930 groups electrolytes based on ethylene 00:21:24.43000:21:24.440 glycol and boric acid in these so called 00:21:27.91000:21:27.920 glycol or borax electrolyte and unwanted 00:21:30.64000:21:30.650 chemical crystal water reaction occurs 00:21:33.25000:21:33.260 according to the scheme acid plus 00:21:35.80000:21:35.810 alcohol gives ester plus water these 00:21:40.60000:21:40.610 borax electrolytes are standard 00:21:42.88000:21:42.890 electrolytes long in use and with a 00:21:45.16000:21:45.170 water content between five and twenty 00:21:47.56000:21:47.570 percent they work at a maximum 00:21:50.35000:21:50.360 temperature of 85 degrees Celsius or 105 00:21:54.19000:21:54.200 degrees Celsius in the entire voltage 00:21:56.47000:21:56.480 range up to 600 V even with these 00:21:59.35000:21:59.360 capacitors the aggressiveness of the 00:22:01.54000:22:01.550 water must be prevented by appropriate 00:22:03.91000:22:03.920 measures almost anhydrous electrolytes 00:22:07.66000:22:07.670 based on organic solvents such as 00:22:10.00000:22:10.010 dimethyl formamide DMF dimethylacetamide 00:22:13.12000:22:13.130 d ma or gamma butyrolactone GBL these 00:22:18.16000:22:18.170 capacitors with organic solvent 00:22:20.35000:22:20.360 electrolytes are suitable for 00:22:21.91000:22:21.920 temperature ranges from 100 00:22:24.25000:22:24.260 five degrees Celsius 125 degrees Celsius 00:22:28.54000:22:28.550 or 150 degrees Celsius have low leakage 00:22:32.29000:22:32.300 current values and have very good 00:22:34.15000:22:34.160 long-term capacitor behavior water-based 00:22:37.84000:22:37.850 electrolytes with high water content up 00:22:40.48000:22:40.490 to 70% water for so-called low impedance 00:22:44.82000:22:44.830 low ESR or high ripple current 00:22:49.95000:22:49.960 electrolytic capacitors with rated 00:22:52.39000:22:52.400 voltages up to 100 volts for low-cost 00:22:54.99000:22:55.000 mass-market applications the 00:22:58.03000:22:58.040 aggressiveness of the water for aluminum 00:23:00.22000:23:00.230 must be prevented with suitable 00:23:01.93000:23:01.940 additives since the amount of liquid 00:23:04.18000:23:04.190 electrolyte during the operating time of 00:23:06.70000:23:06.710 the capacitors decreases over time 00:23:08.50000:23:08.510 through self-healing and by diffusion 00:23:10.90000:23:10.910 through the seal the electrical 00:23:12.85000:23:12.860 parameters of the capacitors may be 00:23:14.80000:23:14.810 adversely affected limiting the service 00:23:17.38000:23:17.390 life or lifetime of wet electrolytic 00:23:21.07000:23:21.080 capacitors see the section on life time 00:23:23.71000:23:23.720 below 00:23:25.40000:23:25.41000:23:28.83000:23:28.840 topic separator 00:23:34.33000:23:34.340 the anode and cathode foils must be 00:23:37.06000:23:37.070 protected from direct contact with each 00:23:39.27900:23:39.289 other because such contacts even at 00:23:41.79900:23:41.809 relatively low voltages may lead to a 00:23:44.34900:23:44.359 short-circuit in case of direct contact 00:23:48.03900:23:48.049 of both foils the oxide layer on the 00:23:50.44000:23:50.450 anode surface gives no protection a 00:23:53.31000:23:53.320 spacer or separator made of a special 00:23:55.89900:23:55.909 highly absorbent paper with high purity 00:23:58.41900:23:58.429 protects the two metal foils from direct 00:24:01.38900:24:01.399 contact this capacitor paper also serves 00:24:05.22900:24:05.239 as a reservoir for the electrolyte to 00:24:07.14900:24:07.159 extend the lifetime of the capacitor the 00:24:10.83900:24:10.849 thickness of the spacer depends on the 00:24:12.99900:24:13.009 rated voltage of the electrolytic 00:24:14.70900:24:14.719 capacitor it is up to 100 volts between 00:24:18.75900:24:18.769 30 and 75 micrometers 00:24:21.43000:24:21.440 for higher voltages several layers of 00:24:24.66900:24:24.679 paper duplex paper are used to increase 00:24:27.27900:24:27.289 the breakdown strength 00:24:33.90000:24:33.910 topic encapsulation 00:24:39.82000:24:39.830 the encapsulation of aluminum 00:24:42.07000:24:42.080 electrolytic capacitors is also made of 00:24:44.65000:24:44.660 aluminum in order to avoid galvanic 00:24:46.75000:24:46.760 reactions normally with an aluminum case 00:24:49.48000:24:49.490 can't tub for radial electrolytic 00:24:52.75000:24:52.760 capacitors it is connected across the 00:24:55.00000:24:55.010 electrolyte with a non defined 00:24:56.68000:24:56.690 resistance to the cathode ground for 00:24:59.98000:24:59.990 axial electrolytic capacitors however 00:25:02.68000:25:02.690 the housing is specifically designed 00:25:04.63000:25:04.640 with a direct contact to the cathode in 00:25:08.32000:25:08.330 case of a malfunction overload or wrong 00:25:11.23000:25:11.240 polarity operating inside the 00:25:13.12000:25:13.130 electrolytic capacitor housing 00:25:15.00000:25:15.010 substantial gas pressure can arise the 00:25:18.58000:25:18.590 tubs are designed to open a pressure 00:25:20.44000:25:20.450 relief vent and release high-pressure 00:25:22.48000:25:22.490 gas including parts of the electrolyte 00:25:25.20000:25:25.210 this vent protects against bursting 00:25:28.21000:25:28.220 explosion or fly away of the metal tab 00:25:31.32000:25:31.330 for smaller housings the pressure relief 00:25:34.27000:25:34.280 vent is carved in the bottom or the 00:25:36.10000:25:36.110 notch of the tub larger capacitors like 00:25:39.19000:25:39.200 screw terminal capacitors have a 00:25:41.56000:25:41.570 lockable overpressure vent and must be 00:25:43.72000:25:43.730 mounted in an upright position 00:25:50.62000:25:50.630 topic sealing 00:25:55.94000:25:55.950 the sealing materials of aluminum 00:25:58.43000:25:58.440 electrolytic capacitors depend on the 00:26:00.80000:26:00.810 different styles for larger screw 00:26:03.77000:26:03.780 terminal and snap in capacitors the 00:26:06.11000:26:06.120 sealing washer is made of a plastic 00:26:07.82000:26:07.830 material axial electrolytic capacitors 00:26:11.81000:26:11.820 usually have a ceiling washer made of 00:26:14.06000:26:14.070 phenolic resin laminated with a layer of 00:26:16.16000:26:16.170 rubber radial electrolytic capacitors 00:26:19.73000:26:19.740 use a rubber plug with a very dense 00:26:21.74000:26:21.750 structure all sealing materials must be 00:26:25.22000:26:25.230 inert to the chemical parts of the 00:26:27.05000:26:27.060 electrolyte and may not contain soluble 00:26:29.33000:26:29.340 compounds that could lead to 00:26:30.86000:26:30.870 contamination of the electrolyte to 00:26:33.40000:26:33.410 avoid leakage the electrolyte must not 00:26:36.71000:26:36.720 be aggressive to the sealing material 00:26:44.03000:26:44.040 topic production 00:26:49.65900:26:49.669 the production process starts with 00:26:52.18000:26:52.190 mother roles first the etched roughened 00:26:55.29900:26:55.309 and preformed anode foil on the mother 00:26:57.45900:26:57.469 role as well as the spacer paper and the 00:26:59.61900:26:59.629 cathode foiler cut to the required width 00:27:02.12900:27:02.139 the foils are fed to an automatic winder 00:27:05.49900:27:05.509 which makes a wound section in a 00:27:07.38900:27:07.399 consecutive operation involving three 00:27:09.72900:27:09.739 sequential steps terminal welding 00:27:12.21900:27:12.229 winding and length cutting in the next 00:27:15.69900:27:15.709 production step the wind section fixed 00:27:18.24900:27:18.259 at the lead-out terminals is soaked with 00:27:20.22900:27:20.239 electrolyte under vacuum impregnation 00:27:22.76900:27:22.779 the impregnated winding is then built 00:27:25.86900:27:25.879 into an aluminum case provided with a 00:27:28.26900:27:28.279 rubber sealing disk and mechanically 00:27:30.43000:27:30.440 tightly sealed by curling there are 00:27:33.21900:27:33.229 after the capacitor is provided with an 00:27:35.70900:27:35.719 insulating shrink sleeve film this 00:27:38.61900:27:38.629 optically ready capacitor is then 00:27:40.77900:27:40.789 contacted at rated voltage in a high 00:27:43.08900:27:43.099 temperature post forming device for 00:27:45.43000:27:45.440 healing all the dielectric defects 00:27:47.49900:27:47.509 resulting from the cutting and winding 00:27:49.38900:27:49.399 procedure after post forming a 100% 00:27:53.68000:27:53.690 final measurement of capacitance leakage 00:27:56.40900:27:56.419 current and impedance takes place taping 00:28:00.24900:28:00.259 closes the manufacturing process the 00:28:02.70900:28:02.719 capacitors are ready for delivery 00:28:10.02000:28:10.030 topic styles 00:28:15.75000:28:15.760 different styles of non solid aluminum 00:28:18.62900:28:18.63900:28:21.30000:28:21.31000:28:23.70000:28:23.710 non solid electrolytes are available in 00:28:26.04000:28:26.050 different styles see pictures above from 00:28:28.59000:28:28.600 left to right 00:28:30.02000:28:30.030 SM DS V chip for surface mounting on 00:28:33.63000:28:33.640 printed circuit boards or substrates 00:28:36.65000:28:36.660 radial led terminals single-ended for 00:28:40.02000:28:40.030 vertical mounting on printed circuit 00:28:42.09000:28:42.100 boards axial lead terminals for 00:28:45.45000:28:45.460 horizontal tht mounting on printed 00:28:48.09000:28:48.100 circuit boards radial pin terminals 00:28:51.57000:28:51.580 snap-in for power applications large 00:28:55.53000:28:55.540 screw terminals for power applications 00:29:02.60000:29:02.610 topic history 00:29:08.18000:29:08.190 in 1875 French researcher Eugene Duke 00:29:12.29000:29:12.300 r8a discovered that certain valve metals 00:29:15.61000:29:15.620 aluminum and others can form an oxide 00:29:18.62000:29:18.630 layer that blocks an electric current 00:29:20.66000:29:20.670 from flowing in one direction but allows 00:29:22.88000:29:22.890 it to flow in the reverse direction 00:29:25.63000:29:25.640 Carol Pollock a producer of accumulators 00:29:28.91000:29:28.920 found out that the oxide layer on an 00:29:31.22000:29:31.230 aluminum anode remained stable in a 00:29:33.38000:29:33.390 neutral or alkaline electrolyte even 00:29:35.90000:29:35.910 when the power was switched off in 1896 00:29:39.71000:29:39.720 he obtained a patent for an electric 00:29:41.99000:29:42.000 liquid capacitor with aluminium 00:29:43.54000:29:43.550 electrodes their electric flow circuits 00:29:46.55000:29:46.560 condensator MIT aluminium electrode and 00:29:49.49000:29:49.500 based on the idea of using the oxide 00:29:51.86000:29:51.870 layer in a polarized capacitor in 00:29:54.08000:29:54.090 combination with a neutral or slightly 00:29:56.18000:29:56.190 alkaline electrolyte the first 00:29:58.25000:29:58.260 electrolytic capacitors realized 00:30:00.38000:30:00.390 industrially consisted of a metallic box 00:30:02.93000:30:02.940 used as cathode filled with a borax 00:30:05.27000:30:05.280 electrolyte dissolved in water in which 00:30:07.70000:30:07.710 a folded aluminum anode plate was 00:30:09.77000:30:09.780 inserted applying a DC voltage from 00:30:13.22000:30:13.230 outside an oxide layer was formed on the 00:30:15.71000:30:15.720 surface of the anode the advantage of 00:30:18.89000:30:18.900 these capacitors was that they were 00:30:20.57000:30:20.580 significantly smaller and cheaper than 00:30:22.67000:30:22.680 all other capacitors at this time with 00:30:24.95000:30:24.960 respect to realized capacitance value 00:30:27.58000:30:27.590 this construction with different styles 00:30:30.59000:30:30.600 of anode construction but with a case as 00:30:32.90000:30:32.910 cathode and a container as the 00:30:34.61000:30:34.620 electrolyte was used up to the 1930s and 00:30:37.49000:30:37.500 was called a wet electrolytic capacitor 00:30:41.30000:30:41.310 referring to its high water content the 00:30:44.38000:30:44.390 first common application of wet aluminum 00:30:47.57000:30:47.580 electrolytic capacitors was in large 00:30:49.76000:30:49.770 telephone exchanges to reduce relay 00:30:52.46000:30:52.470 Hache noise on the 48 volt DC power 00:30:55.55000:30:55.560 supply the development of AC operated 00:30:59.27000:30:59.280 domestic radio receivers in the late 00:31:01.60000:31:01.610 1920s created a demand for large 00:31:04.28000:31:04.290 capacitance for the time and 00:31:06.23000:31:06.240 high-voltage capacitors for the valve 00:31:08.36000:31:08.370 amplifier technique typically at least 00:31:10.49000:31:10.500 four micro farad's and rated at around 00:31:13.19000:31:13.200 500 volts DC wax paper and oiled silk 00:31:17.45000:31:17.460 film capacitors were available but 00:31:19.82000:31:19.830 devices with that order of capacitor 00:31:22.04000:31:22.050 and voltage rating were bulky and 00:31:24.11000:31:24.120 prohibitively expensive the ancestor of 00:31:27.74000:31:27.750 the modern electrolytic capacitor was 00:31:29.93000:31:29.940 patented by Samuel Rubin in 1925 who 00:31:33.65000:31:33.660 teamed with Phillip Mallory the founder 00:31:35.81000:31:35.820 of the battery company that is now known 00:31:37.79000:31:37.800 as Duracell international Reubens idea 00:31:41.18000:31:41.190 adopted the stacked construction of a 00:31:43.28000:31:43.290 silver mica capacitor he introduced a 00:31:46.31000:31:46.320 separate second foil to contact the 00:31:48.47000:31:48.480 electrolyte adjacent the anode foil 00:31:50.63000:31:50.640 instead of using the electrolyte filled 00:31:52.85000:31:52.860 container as the cathode of the 00:31:54.56000:31:54.570 capacitor the stacked second foil got 00:31:57.86000:31:57.870 its own terminal additional to the anode 00:32:00.05000:32:00.060 terminal and the container had no longer 00:32:02.33000:32:02.340 an electrical function this type of 00:32:05.30000:32:05.310 electrolytic capacitor with one anode 00:32:07.73000:32:07.740 foil separated from a cathode foil by a 00:32:10.43000:32:10.440 liquid or gel like electrolyte of a non 00:32:12.83000:32:12.840 aqueous nature which is therefore dry in 00:32:15.50000:32:15.510 the sense of having a very low water 00:32:17.39000:32:17.400 content became known as their tri type 00:32:20.99000:32:21.000 of electrolytic capacitor this invention 00:32:23.72000:32:23.730 together with the invention of wound 00:32:26.00000:32:26.010 foils separated with a paper spacer 1927 00:32:29.75000:32:29.760 by a Eckel hydra verka germany reduced 00:32:33.05000:32:33.060 the size and the price significantly 00:32:34.60000:32:34.610 which helped make the new radios 00:32:37.16000:32:37.170 affordable for a broader group of 00:32:38.99000:32:39.000 customers 00:32:39.83000:32:39.840 William do Billy R whose first patent 00:32:42.11000:32:42.120 for electrolytic capacitors was filed in 00:32:44.74000:32:44.750 1928 industrialized the new ideas for 00:32:48.14000:32:48.150 electrolytic capacitors and started 00:32:50.45000:32:50.460 large-scale commercial production in 00:32:52.58000:32:52.590 1931 in the Cornell EE @cd Factory in 00:32:56.57000:32:56.580 Plainfield New Jersey at the same time 00:33:00.17000:33:00.180 in Berlin Germany the Hydra verka an aeg 00:33:04.94000:33:04.950 company started the production of 00:33:07.13000:33:07.140 electrolytic capacitors in large 00:33:09.11000:33:09.120 quantities already in his patent 00:33:12.59000:33:12.600 application of 1886 pollock wrote that 00:33:15.62000:33:15.630 the capacitance of the capacitor 00:33:16.96000:33:16.970 increased if the surface of the anode 00:33:19.46000:33:19.470 foil was roughened a number of methods 00:33:22.46000:33:22.470 have since been developed for roughening 00:33:24.80000:33:24.810 the anode surface mechanical methods 00:33:27.23000:33:27.240 like sandblasting or scratching and 00:33:29.57000:33:29.580 chemical etching with acids and acid 00:33:31.46000:33:31.470 salts forced by high currents some of 00:33:34.94000:33:34.950 these methods 00:33:35.85000:33:35.860 were developed in the CD factory between 00:33:38.26900:33:38.279 1931 and 1938 today 2014 00:33:44.00000:33:44.010 electrochemically etching of low voltage 00:33:45.93000:33:45.940 foils can achieve up to a 200 fold 00:33:48.81000:33:48.820 increase in surface area compared to a 00:33:51.29900:33:51.309 smooth surface progress relating to the 00:33:54.81000:33:54.820 etching process is the reason for the 00:33:56.88000:33:56.890 ongoing reduction in the dimensions of 00:33:59.15900:33:59.169 aluminum electrolytic capacitors over 00:34:01.52900:34:01.539 the past decades the period after World 00:34:05.25000:34:05.260 War 2 is associated with a rapid 00:34:07.71000:34:07.720 development in radio and television 00:34:09.62900:34:09.639 technology as well as in industrial 00:34:12.08900:34:12.099 applications which had great influence 00:34:14.52000:34:14.530 on production quantities but also on 00:34:16.98000:34:16.990 Styles sizes and series diversification 00:34:19.80000:34:19.810 of electrolytic capacitors new 00:34:23.04000:34:23.050 electrolytes based on organic liquids 00:34:25.53000:34:25.540 reduced leakage currents and ESR 00:34:27.86900:34:27.879 broadened temperature ranges and 00:34:29.94000:34:29.950 increased lifetimes corrosion phenomena 00:34:33.45000:34:33.460 caused by chlorine and water could be 00:34:35.55000:34:35.560 avoided by a higher purity manufacturing 00:34:38.25000:34:38.260 processes and by using additives in the 00:34:40.61900:34:40.629 electrolytes the development of tantalum 00:34:44.36900:34:44.379 electrolytic capacitors in the early 00:34:46.47000:34:46.480 1950s with manganese dioxide as solid 00:34:49.80000:34:49.810 electrolyte which has a 10 times better 00:34:52.13900:34:52.149 conductivity than all other types of non 00:34:54.65900:34:54.669 solid electrolytes also influenced the 00:34:57.18000:34:57.190 development of aluminium electrolytic 00:34:59.07000:34:59.080 capacitors in 1964 the first aluminum 00:35:03.81000:35:03.82000:35:05.94000:35:05.950 electrolytes solid aluminum capacitor 00:35:08.55000:35:08.560 cell appeared on the market developed by 00:35:11.31000:35:11.320 Philips the decades from 1970 to 1990 00:35:15.32900:35:15.339 were marked by the development of 00:35:17.01000:35:17.020 various new professional aluminum 00:35:19.02000:35:19.030 electrolytic capacitor series with F II 00:35:22.22000:35:22.230 very low leakage currents or with long 00:35:25.29000:35:25.300 life characteristics or for higher 00:35:27.35900:35:27.369 temperatures up to 125 degrees Celsius 00:35:31.02000:35:31.030 which were specifically suited to 00:35:33.15000:35:33.160 certain industrial applications the 00:35:36.30000:35:36.310 great diversity of the many series of 00:35:38.76000:35:38.77000:35:40.98000:35:40.990 non solid electrolytes up to now 2014 is 00:35:44.55000:35:44.560 an indicator of the adaptability of the 00:35:46.68000:35:46.690 capacitors to meet different industrial 00:35:48.75000:35:48.760 require 00:35:50.16000:35:50.170 in 1983 a further reduction of the ESR 00:35:54.54000:35:54.550 was achieved by sanyo with its OS con 00:35:58.28000:35:58.290 aluminum electrolytic capacitors these 00:36:01.50000:36:01.510 capacitors use as solid organic 00:36:03.66000:36:03.670 conductor the charge transfer salt TT 00:36:06.51000:36:06.520 FTC NQ tetra cyano queneau de methane 00:36:09.78000:36:09.790 which provided an improvement in 00:36:11.79000:36:11.800 conductivity by a factor of 10 with 00:36:14.16000:36:14.170 respect to the manganese dioxide 00:36:15.80000:36:15.810 electrolyte the ESR values of T cnq 00:36:20.67000:36:20.680 capacitors were significantly reduced by 00:36:23.22000:36:23.230 the discovery of conducting polymers by 00:36:25.53000:36:25.540 Alan J Higa Alan mcdermid and Hideki 00:36:28.44000:36:28.450 shirokawa the conductivity of conductive 00:36:31.83000:36:31.840 polymers such as poly pyrole 14 or PE do 00:36:35.40000:36:35.410 TR better than that of TC n Q by a 00:36:38.04000:36:38.050 factor of 100 to 500 and are close to 00:36:41.19000:36:41.200 the conductivity of metals in 1991 00:36:45.15000:36:45.160 panasonic put its SP cap a polymer 00:36:49.47000:36:49.480 aluminum 00:36:51.17000:36:51.180 electrolytic capacitor on the market 00:36:53.72000:36:53.730 these electrolytic capacitors with 00:36:56.39000:36:56.400 polymer electrolytes achieved ESR values 00:36:58.73000:36:58.740 low enough to compete with ceramic 00:37:01.19000:37:01.200 multi-layer capacitors mlcc's they were 00:37:05.27000:37:05.280 still less expensive than tantalum 00:37:07.40000:37:07.410 capacitors and were a short time later 00:37:09.53000:37:09.540 used in devices with a flat design such 00:37:12.47000:37:12.480 as laptops and cell phones new 00:37:15.89000:37:15.900 water-based electrolytes were developed 00:37:18.29000:37:18.300 in Japan from the mid-1980s with the 00:37:20.99000:37:21.000 goal of reducing ESR for inexpensive non 00:37:23.90000:37:23.910 solid electrolytic capacitors water is 00:37:27.56000:37:27.570 inexpensive an effective solvent for 00:37:30.02000:37:30.030 electrolytes and significantly improves 00:37:32.45000:37:32.460 the conductivity of the electrolyte the 00:37:35.93000:37:35.940 Japanese manufacturer Rubicon was a 00:37:38.57000:37:38.580 leader in the development of new 00:37:40.37000:37:40.380 water-based electrolyte systems with 00:37:42.62000:37:42.630 enhanced conductivity in the late 1990s 00:37:45.97000:37:45.980 the new series of non solid capacitors 00:37:49.46000:37:49.470 with water based electrolyte was called 00:37:51.74000:37:51.750 in the data sheets low ESR low impedance 00:37:57.31000:37:57.320 ultra-low impedance or high ripple 00:38:01.49000:38:01.500 current series a stolen recipe of such a 00:38:06.44000:38:06.450 water-based electrolyte in which 00:38:08.57000:38:08.580 important stabilizing substances were 00:38:11.06000:38:11.070 absent led in the years 2000 to 2005 to 00:38:15.08000:38:15.090 the problem of mass bursting capacitors 00:38:17.21000:38:17.220 in computers and power supplies which 00:38:19.61000:38:19.620 became known under the term capacitor 00:38:22.34000:38:22.350 plagued in these capacitors the water 00:38:25.37000:38:25.380 reacts quite aggressively and even 00:38:27.47000:38:27.480 violently with aluminium accompanied by 00:38:29.69000:38:29.700 strong heat and gas development in the 00:38:32.21000:38:32.220 capacitor and often leads to the 00:38:34.13000:38:34.140 explosion of the capacitor 00:38:41.00000:38:41.010 topic electrical parameters 00:38:47.58900:38:47.599 the electrical characteristics of 00:38:50.07900:38:50.089 capacitors are harmonized by the 00:38:51.96900:38:51.979 international generic specification IEC 00:38:55.94900:38:55.959 60309 asjuan in this standard the 00:39:00.57900:39:00.589 electrical characteristics of capacitors 00:39:03.09900:39:03.109 are described by an idealized series 00:39:05.46900:39:05.479 equivalent circuit with electrical 00:39:07.39000:39:07.400 components that model all ohmic losses 00:39:09.83900:39:09.849 capacitive and inductive parameters of 00:39:12.45900:39:12.469 an electrolytic capacitor see the 00:39:15.88000:39:15.890 capacitance of the capacitor are ESR the 00:39:19.98900:39:19.999 equivalent series resistance which 00:39:22.26900:39:22.279 summarizes all ohmic losses of the 00:39:24.18900:39:24.199 capacitor usually abbreviated as ESR L 00:39:29.52900:39:29.539 ESL the equivalent series inductance 00:39:32.14000:39:32.150 which is the effective self inductance 00:39:34.77900:39:34.789 of the capacitor usually abbreviated as 00:39:37.82900:39:37.839 ESL 00:39:40.74000:39:40.750 our leakage the resistance that 00:39:42.87000:39:42.880 represents the leakage current 00:39:48.81000:39:48.820 topic capacitance standard values and 00:39:52.56000:39:52.570 tolerances 00:39:56.91000:39:56.920 the basic unit of electrolytic 00:39:59.40000:39:59.410 capacitors capacitance is the micro 00:40:01.77000:40:01.780 farad mu F or less correctly UF the 00:40:06.00000:40:06.010 capacitance value specified in 00:40:08.19000:40:08.200 manufacturers data sheets is called the 00:40:10.65000:40:10.660 rated capacitance C R or nominal 00:40:12.99000:40:13.000 capacitance CN and is the value for 00:40:15.54000:40:15.550 which the capacitor has been designed 00:40:18.35000:40:18.360 standardized measuring conditions for 00:40:20.97000:40:20.980 electrolytic capacitors are an AC 00:40:22.89000:40:22.900 measurement with 0.5 volts at a 00:40:25.77000:40:25.780 frequency of 100 and 100 twentieths of a 00:40:28.95000:40:28.960 Hertz and a temperature of 20 degrees 00:40:30.86000:40:30.870 Celsius the capacitance value of an 00:40:34.92000:40:34.930 electrolytic capacitor depends on the 00:40:37.29000:40:37.300 measuring frequency and temperature the 00:40:40.32000:40:40.330 value at a measuring frequency of 1 00:40:42.60000:40:42.610 kilohertz is about 10 percent less than 00:40:44.85000:40:44.860 the 100 and 100 twentieths of a Hertz 00:40:47.79000:40:47.800 value therefore the capacitance values 00:40:51.51000:40:51.520 of electrolytic capacitors are not 00:40:53.58000:40:53.590 directly comparable and differ from 00:40:55.44000:40:55.450 those of film capacitors or ceramic 00:40:57.87000:40:57.880 capacitors whose capacitance is measured 00:41:00.51000:41:00.520 at 1 kilohertz or higher measured with 00:41:03.93000:41:03.940 an AC measuring method with 100 and 100 00:41:07.11000:41:07.120 twentieths of a Hertz the measured 00:41:09.03000:41:09.040 capacitance value is the closest value 00:41:11.34000:41:11.350 to the electrical charge stored in the 00:41:13.68000:41:13.690 capacitor the stored charge is measured 00:41:16.68000:41:16.690 with a special discharge method and is 00:41:19.02000:41:19.030 called DC capacitance the DC capacitance 00:41:23.25000:41:23.260 is about 10 percent higher than the 100 00:41:25.95000:41:25.960 and 100 twentieths of a Hertz AC 00:41:28.25000:41:28.260 capacitance the DC capacitance is of 00:41:32.31000:41:32.320 interest for discharge applications like 00:41:34.68000:41:34.690 photo flash the percentage of allowed 00:41:38.16000:41:38.170 deviation of the measured capacitance 00:41:40.38000:41:40.390 from the rated value is called 00:41:42.24000:41:42.250 capacitance tolerance electrolytic 00:41:45.57000:41:45.580 capacitors are available in different 00:41:47.49000:41:47.500 tolerance series whose values are 00:41:49.65000:41:49.660 specified in the e series specified in 00:41:52.44000:41:52.450 IEC 60309 C 60,000 and 62 rated 00:42:06.27000:42:06.280 capacitance III series tolerance plus or 00:42:09.75000:42:09.760 minus 20 00:42:10.77900:42:10.789 sent letter code m-rated capacitance C 00:42:15.69900:42:15.709 six series tolerance plus or minus 20 00:42:19.02900:42:19.039 percent letter code M rated capacitance 00:42:23.82900:42:23.839 e 12 series tolerance plus or minus 10% 00:42:27.45900:42:27.469 letter code K the required capacitance 00:42:31.74900:42:31.759 tolerance is determined by the 00:42:33.45900:42:33.469 particular application electrolytic 00:42:36.33900:42:36.349 capacitors that are often used for 00:42:38.46900:42:38.479 filtering and bypassing capacitors do 00:42:40.92900:42:40.939 not need narrow tolerances because they 00:42:43.20900:42:43.219 are not used for accurate frequency 00:42:45.40000:42:45.410 applications such as for oscillator 's 00:42:52.93000:42:52.940 topic rated and category voltage 00:42:59.73000:42:59.740 in IEC 60309 asjuan the allowed 00:43:04.92000:43:04.930 operating voltage is called their rated 00:43:07.77000:43:07.780 voltage you're their nominal voltage un 00:43:12.93000:43:12.940 the rated voltage is the maximum DC 00:43:16.02000:43:16.030 voltage or peak pulse voltage that may 00:43:18.54000:43:18.550 be applied continuously at any 00:43:20.33900:43:20.349 temperature within the rated temperature 00:43:22.20000:43:22.210 range the voltage proof of electrolytic 00:43:26.40000:43:26.410 capacitors which is directly 00:43:28.26000:43:28.270 proportional to the dielectric layer 00:43:30.30000:43:30.310 thickness decreases with increasing 00:43:32.37000:43:32.380 temperature for some applications it is 00:43:35.73000:43:35.740 important to use a high temperature 00:43:37.71000:43:37.720 range lowering the voltage applied at a 00:43:41.09900:43:41.109 higher temperature maintain safety 00:43:43.41000:43:43.420 margins for some capacitor types 00:43:46.38000:43:46.390 therefore the IEC standard specifies a 00:43:49.32000:43:49.330 second temperature de rated voltage 00:43:52.57900:43:52.589 through a higher temperature range that 00:43:55.47000:43:55.480 category voltage you see the category 00:43:59.67000:43:59.680 voltage is the maximum DC voltage peak 00:44:02.73000:44:02.740 pulse voltage or superimposed AC voltage 00:44:05.82000:44:05.830 that may be applied continuously to a 00:44:07.92000:44:07.930 capacitor at any temperature within the 00:44:10.05000:44:10.060 category temperature range 00:44:16.95000:44:16.960 topic surge voltage 00:44:22.99000:44:23.000 aluminum electrolytic capacitors can be 00:44:25.81900:44:25.829 applied for a short time with an 00:44:27.68000:44:27.690 over-voltage 00:44:28.46000:44:28.470 also called a surge voltage the surge 00:44:31.88000:44:31.890 voltage indicates the maximum voltage 00:44:34.28000:44:34.290 value within the temperature range that 00:44:36.74000:44:36.750 may be applied during the lifetime at a 00:44:38.80900:44:38.819 frequency of 1000 cycles with a dwell 00:44:41.69000:44:41.700 time of 30 seconds in a pause of 5 00:44:44.24000:44:44.250 minutes and 30 seconds in each instance 00:44:46.49000:44:46.500 without causing any visible damage to 00:44:48.92000:44:48.930 the capacitor or a capacitance change of 00:44:51.53000:44:51.540 more than 15 percent for capacitors with 00:44:55.40000:44:55.410 a rated voltage of 315 volts the surge 00:44:58.78900:44:58.799 voltage is 1.15 times the rated voltage 00:45:02.08900:45:02.099 and for capacitors with a rated voltage 00:45:04.57900:45:04.589 exceeding 315 volts the surge voltage is 00:45:08.59900:45:08.609 1.10 times the rated voltage 00:45:16.34000:45:16.350 topic transient voltage 00:45:22.51000:45:22.52000:45:25.25000:45:25.260 non solid electrolyte are relatively 00:45:27.34900:45:27.359 insensitive to high and short-term 00:45:29.45000:45:29.460 transient voltages higher than the surge 00:45:31.79000:45:31.800 voltage if the frequency and the energy 00:45:34.43000:45:34.440 content of the transients is low this 00:45:37.46000:45:37.470 ability depends on the rated voltage and 00:45:40.07000:45:40.080 component size low energy transient 00:45:43.19000:45:43.200 voltages lead to a voltage limitation 00:45:45.71000:45:45.720 similar to a Zener diode the 00:45:48.71000:45:48.720 electrochemical oxide forming processes 00:45:51.29000:45:51.300 take place when voltage in correct 00:45:53.66000:45:53.670 polarity is applied and generates an 00:45:56.00000:45:56.010 additional oxide when transients arise 00:45:58.75000:45:58.760 this formation is accompanied with heat 00:46:01.91000:46:01.920 and hydrogen gas generation this is 00:46:04.64000:46:04.650 tolerable if the energy content of the 00:46:07.01000:46:07.020 transient is low however when a 00:46:10.07000:46:10.080 transient peak voltage causes an 00:46:12.34900:46:12.359 electric field strength that is too high 00:46:14.59900:46:14.609 for the dielectric it can directly cause 00:46:17.08900:46:17.099 a short circuit an unambiguous and 00:46:20.39000:46:20.400 general specification of tolerable 00:46:22.55000:46:22.560 transients or peak voltages is not 00:46:24.89000:46:24.900 possible in every case transients arise 00:46:28.43000:46:28.440 the application has to be carefully 00:46:30.74000:46:30.750 approved electrolytic capacitors with 00:46:34.28000:46:34.290 solid electrolyte cannot withstand 00:46:36.25000:46:36.260 transients or peak voltages higher than 00:46:38.99000:46:39.000 the surge voltage transients for this 00:46:42.17000:46:42.180 type of electrolytic capacitor may 00:46:44.35900:46:44.369 destroy the component 00:46:47.10900:46:47.11900:46:50.53000:46:50.540 topic reverse voltage 00:46:56.58900:46:56.599 electrolytic capacitors are polarized 00:46:59.32900:46:59.339 capacitors and generally require an 00:47:01.54900:47:01.559 anode electrode voltage to be positive 00:47:03.94900:47:03.959 relative to the cathode voltage 00:47:06.30900:47:06.319 however the cathode foil of aluminum 00:47:09.41000:47:09.420 electrolytic capacitors is provided with 00:47:11.90000:47:11.910 a very thin natural air originated oxide 00:47:14.71900:47:14.729 layer this oxide layer has a voltage 00:47:17.74900:47:17.759 proof of approximately 1 to 1.5 V 00:47:21.10900:47:21.119 therefore aluminum electrolytic 00:47:22.98900:47:22.999 capacitors with non solid electrolyte 00:47:25.60900:47:25.619 can withstand a very small reverse 00:47:27.67900:47:27.689 voltage and for example can be measured 00:47:30.16900:47:30.179 with an AC voltage of about 0.5 volts as 00:47:33.73900:47:33.749 specified in relevant standards at a 00:47:37.45900:47:37.469 reverse voltage lower than minus 1.5 00:47:40.30900:47:40.319 volts at room temperature the cathode 00:47:42.97900:47:42.989 aluminum foil begins to build up an 00:47:45.16900:47:45.179 oxide layer corresponding to the applied 00:47:47.44900:47:47.459 voltage this is aligned with generating 00:47:50.56900:47:50.579 hydrogen gas with increasing pressure at 00:47:53.44900:47:53.459 the same time the oxide layer on the 00:47:56.02900:47:56.039 anode foil begins dissolution of the 00:47:58.33900:47:58.349 oxide which weakens the voltage proof it 00:48:01.84900:48:01.859 is now a question of the outside circuit 00:48:04.42900:48:04.439 whether they're increasing gas pressure 00:48:06.16900:48:06.179 from oxidation leads to bursting of the 00:48:08.50900:48:08.519 case or the weakened anode oxide leads 00:48:11.23900:48:11.249 to a breakdown with a short circuit if 00:48:14.39000:48:14.400 the outside circuit is high ohmic the 00:48:16.96900:48:16.979 capacitor fails in the vent opens due to 00:48:19.66900:48:19.679 high gas pressure if the outside circuit 00:48:23.08900:48:23.099 is low ohmic an internal short-circuit 00:48:25.91000:48:25.920 is more probable in every case a reverse 00:48:29.05900:48:29.069 voltage lower than minus 1.5 volts at 00:48:32.32900:48:32.339 room temperature may cause the component 00:48:34.72900:48:34.739 to catastrophically fail due to a 00:48:36.73900:48:36.749 dielectric breakdown or overpressure 00:48:38.95900:48:38.969 which causes the capacitor to burst 00:48:41.23900:48:41.249 often in a spectacularly dramatic 00:48:43.51900:48:43.529 fashion 00:48:44.31900:48:44.329 modern electrolytic capacitors have a 00:48:47.17900:48:47.189 safety vent that is typically either a 00:48:49.37000:48:49.380 scored section of the case or a 00:48:51.10900:48:51.119 specially designed end sealed to vent 00:48:53.29900:48:53.309 the hot gas liquid but ruptures can 00:48:55.64000:48:55.650 still be dramatic to minimize the 00:48:58.93900:48:58.949 likelihood of a polarized electrolytic 00:49:01.33900:49:01.349 being incorrectly inserted into a 00:49:03.28900:49:03.299 circuit polarity has to be very clearly 00:49:06.04900:49:06.059 indicated on the case see the section 00:49:08.26900:49:08.279 headed polarity mark 00:49:11.92000:49:11.930 special bipolar capacitors designed for 00:49:15.08000:49:15.090 AC operation usually referred to as 00:49:17.71000:49:17.720 bipolar non-polarised 00:49:21.32000:49:21.330 or NP types are available in these the 00:49:26.33000:49:26.340 capacitors have to anode foils of 00:49:28.76000:49:28.770 opposite polarity connected in series on 00:49:31.85000:49:31.860 each of the alternate halves of the AC 00:49:34.34000:49:34.350 cycle one anode acts as a blocking 00:49:36.92000:49:36.930 dielectric preventing reverse voltage 00:49:39.14000:49:39.150 from damaging the opposite anode but 00:49:42.35000:49:42.360 these bipolar electrolytic capacitors 00:49:44.84000:49:44.850 are not adaptable for main AC 00:49:46.63000:49:46.640 applications instead of power capacitors 00:49:49.34000:49:49.350 with metallized polymer film or paper 00:49:51.74000:49:51.750 dielectric 00:49:57.63000:49:57.640 topic impedance 00:50:03.18000:50:03.190 in general a capacitor is seen as a 00:50:06.00000:50:06.010 storage component for electric energy 00:50:08.60000:50:08.610 but this is only one capacitor function 00:50:11.94000:50:11.950 a capacitor can also act as an AC 00:50:14.67000:50:14.680 resistor especially aluminium 00:50:17.28000:50:17.290 electrolytic capacitors are used in many 00:50:19.68000:50:19.690 applications as a decoupling capacitors 00:50:22.32000:50:22.330 to filter or bypass undesired biased AC 00:50:25.29000:50:25.300 frequencies to the ground or for 00:50:27.45000:50:27.460 capacitive coupling of audio AC signals 00:50:30.47000:50:30.480 then the dielectric is used only for 00:50:33.33000:50:33.340 blocking DC for such applications the AC 00:50:36.81000:50:36.820 resistance the impedance is as important 00:50:39.69000:50:39.700 as the capacitance value the impedance 00:50:43.26000:50:43.270 is the vector sum of reactance and 00:50:45.39000:50:45.400 resistance 00:50:46.23000:50:46.240 it describes the phase difference in the 00:50:48.48000:50:48.490 ratio of amplitudes between sinusoidally 00:50:51.24000:50:51.250 varying voltage and sinusoidally varying 00:50:53.40000:50:53.410 current at a given frequency in an AC 00:50:56.07000:50:56.080 circuit in this sense impedance can be 00:50:59.61000:50:59.620 used like Ohm's law Z equals u carrot 00:51:07.50000:51:07.510 eye carrot equals u 00:51:15.11000:51:15.120 e f 00:51:18.07000:51:18.080 f 00:51:19.66000:51:19.670 I II F 00:51:24.21000:51:24.220 F display style Z equals track hat u hat 00:51:29.40000:51:29.410 immerse equals prac u underscore mathram 00:51:32.94000:51:32.950 f i underscore mass from f in other 00:51:36.81000:51:36.820 words impedance is a frequency dependent 00:51:39.78000:51:39.790 AC resistance and possesses both 00:51:41.94000:51:41.950 magnitude and phase at a particular 00:51:43.92000:51:43.930 frequency in capacitor datasheets 00:51:48.08900:51:48.099 only the impedance magnitude Z is 00:51:50.76000:51:50.770 specified and simply written as Zed in 00:51:54.18000:51:54.190 this sense the impedance is a measure of 00:51:57.21000:51:57.220 the capacitors ability to pass 00:51:59.04000:51:59.050 alternating currents impedance can be 00:52:02.84900:52:02.859 calculated using the idealized 00:52:04.95000:52:04.960 components of a capacitors series 00:52:07.32000:52:07.330 equivalent circuit including an ideal 00:52:09.75000:52:09.760 capacitor see display style script style 00:52:15.15000:52:15.160 see a resistor 00:52:18.64000:52:18.650 II 00:52:20.01000:52:20.020 s 00:52:21.74000:52:21.750 ah display style script style ESR and an 00:52:27.35000:52:27.360 inductance 00:52:29.18000:52:29.19000:52:30.59900:52:30.60900:52:32.38000:52:32.390 l display style script style ESL in this 00:52:38.10900:52:38.119 case the impedance at the angular 00:52:40.12000:52:40.130 frequency Omega display style Omega is 00:52:46.17000:52:46.180 therefore given by the geometric complex 00:52:49.15000:52:49.160 addition of ESR by a capacitive 00:52:51.73000:52:51.740 reactance capacitance 00:52:54.51000:52:54.520 X see 00:52:57.85000:52:57.860 equals minus 00:53:01.25000:53:01.260 one omega-c display style X underscore C 00:53:08.48000:53:08.490 equals prac one Omega C and by an 00:53:12.71000:53:12.720 inductive reactance inductance X 00:53:17.41000:53:17.420 Elle 00:53:19.04000:53:19.050 equals Omega L e 00:53:25.08000:53:25.09000:53:26.95000:53:26.960 l displaced dialects underscore ell 00:53:30.58000:53:30.590 equals Omega L underscore mass from ESL 00:53:34.50000:53:34.510 then Zed display Styles head is given by 00:53:41.94000:53:41.950 Z equals e s 00:53:48.97000:53:48.980 our two plus 00:53:53.67000:53:53.680 x c+ - 00:54:00.91000:54:00.920 X 00:54:02.55000:54:02.560 l to display styles aired equals s QR t 00:54:08.73000:54:08.740 ESR carrot 2 + X underscore mathram C + 00:54:13.98000:54:13.990 X underscore mass from L carrot 2 in the 00:54:18.81000:54:18.820 special case of resonance in which the 00:54:21.24000:54:21.250 both reactive resistances 00:54:25.12000:54:25.130 x-c display style script style X 00:54:29.51000:54:29.520 underscore see 00:54:31.76000:54:31.770 and 00:54:33.17000:54:33.18000:54:34.68000:54:34.690 l display style script style X 00:54:38.46000:54:38.470 underscore L have the same value 00:54:42.87000:54:42.88000:54:46.43000:54:46.440 equals 00:54:47.93000:54:47.94000:54:49.58000:54:49.59000:54:53.21000:54:53.220 underscore C equals X underscore L then 00:54:57.98000:54:57.990 the impedance is only determined by E 00:55:02.52000:55:02.53000:55:04.21000:55:04.220 ah display style script style ESR the 00:55:09.58000:55:09.590 impedance specified in the data sheets 00:55:11.98000:55:11.990 of various capacitors often shows 00:55:14.17000:55:14.180 typical curves for different capacitance 00:55:16.59900:55:16.609 values the impedance at the resonant 00:55:19.83900:55:19.849 frequency defines the best working point 00:55:22.33000:55:22.340 for coupling or decoupling circuits the 00:55:25.81000:55:25.820 higher the capacitance the lower the 00:55:27.82000:55:27.830 operable frequency range due to their 00:55:30.70000:55:30.710 large capacitance values aluminum 00:55:33.25000:55:33.260 electrolytic capacitors have relatively 00:55:35.56000:55:35.570 good decoupling properties in the lower 00:55:37.66000:55:37.670 frequency range up to about one 00:55:39.79000:55:39.800 megahertz or a little more this and the 00:55:42.88000:55:42.890 relatively low price is often the reason 00:55:45.04000:55:45.050 for using electrolytic capacitors in 50 00:55:48.04000:55:48.050 sixtieths of a Hertz standard or 00:55:50.08000:55:50.090 switched mode power supplies 00:55:56.98000:55:56.990 topic ESR on dissipation factor tan 00:56:00.97000:56:00.980 Delta 00:56:04.90000:56:04.910 typical impedance in the SR curves as a 00:56:07.96000:56:07.970 function of frequency and temperature 00:56:10.58900:56:10.599 the equivalent series resistance ESR 00:56:14.17000:56:14.180 summarizes all resistive losses of the 00:56:16.63000:56:16.640 capacitor these are the terminal 00:56:19.29900:56:19.309 resistances the contact resistance of 00:56:21.94000:56:21.950 the electrode contact the line 00:56:23.85900:56:23.869 resistance of the electrodes the 00:56:25.96000:56:25.970 electrolyte resistance and the 00:56:27.78900:56:27.799 dielectric losses in the dielectric 00:56:29.85900:56:29.869 oxide layer ESR depends on temperature 00:56:32.85900:56:32.869 and frequency for aluminum electrolytic 00:56:35.94000:56:35.95000:56:38.55900:56:38.569 the ESR generally decreases with 00:56:40.83900:56:40.849 increasing frequency and temperature ESR 00:56:44.52900:56:44.539 influences the remaining superimposed AC 00:56:47.34900:56:47.359 ripple behind smoothing and may 00:56:49.39000:56:49.400 influence circuit functionality related 00:56:52.93000:56:52.940 to the capacitor ESR is accountable for 00:56:55.56900:56:55.579 internal heat generation if a ripple 00:56:57.99900:56:58.009 current flows over the capacitor this 00:57:00.94000:57:00.950 internal heat reduces capacitor lifetime 00:57:04.95000:57:04.960 referring to the IEC and 60,000 384 00:57:09.84900:57:09.859 minus one standard the impedance values 00:57:12.67000:57:12.680 of electrolytic capacitors are measured 00:57:14.89000:57:14.900 at 10 kilohertz or 100 kilohertz 00:57:17.04900:57:17.059 depending on the capacitance and voltage 00:57:19.74900:57:19.759 of the capacitor for aluminium 00:57:22.69000:57:22.700 electrolytic capacitors for historical 00:57:25.29900:57:25.309 reasons sometimes the dissipation factor 00:57:27.75900:57:27.769 tan Delta is specified in the relevant 00:57:30.37000:57:30.380 data sheets instead of the e 00:57:34.24000:57:34.25000:57:35.96000:57:35.97000:57:41.36000:57:41.370 dissipation factor is determined by the 00:57:43.67000:57:43.680 tangent of the phase angle between the 00:57:45.95000:57:45.960 capacitive reactance X C 00:57:51.44000:57:51.450 display style script style X underscore 00:57:54.47000:57:54.480 C - the inductive reactance 00:57:59.29000:57:59.30000:58:00.99000:58:01.000 l display style scripts dialects 00:58:04.53000:58:04.540 underscore ell and the e s 00:58:11.17000:58:11.180 ah display style script style ESR if the 00:58:16.81000:58:16.820 inductance II 00:58:20.82000:58:20.830 s-l display style script style ESL is 00:58:26.98000:58:26.990 small the dissipation factor for a given 00:58:29.77000:58:29.780 frequency can be approximated as tan 00:58:34.08000:58:34.09000:58:36.28000:58:36.290 equals ESR Omega C display style tan 00:58:44.20000:58:44.210 Delta equals mbox ESR CDO T Omega C 00:58:53.09000:58:53.100 topic ripple current 00:58:58.82000:58:58.830 a ripple current is the rms value of a 00:59:01.97000:59:01.980 superimposed AC current of any frequency 00:59:04.58000:59:04.590 in any waveform of the current curve for 00:59:07.16000:59:07.170 continuous operation it arises for 00:59:10.55000:59:10.560 example in power supplies including 00:59:13.19000:59:13.200 switched-mode power supplies after 00:59:15.20000:59:15.210 rectifying an AC voltage and flows as 00:59:17.96000:59:17.970 bias charge and discharge current 00:59:20.06000:59:20.070 through the decoupling or smoothing 00:59:21.77000:59:21.780 capacitor due to the ESR of the 00:59:25.16000:59:25.170 capacitor the ripple current IR causes 00:59:27.77000:59:27.780 electrical power losses p VL P V E 00:59:35.81000:59:35.820 l equals AI 00:59:40.74000:59:40.750 ah - II 00:59:45.05000:59:45.06000:59:46.99000:59:47.000 our display style P underscore Val 00:59:50.65000:59:50.660 equals I underscore our caret to see do 00:59:54.28000:59:54.290 t es R which result in heat generation 00:59:58.45000:59:58.460 inside the capacitor winding call this 01:00:02.11001:00:02.120 internally generated heat together with 01:00:04.72001:00:04.730 ambient temperature and possibly other 01:00:06.79001:00:06.800 external heat sources leads to a 01:00:09.07001:00:09.080 capacitor core temperature whose hottest 01:00:11.50001:00:11.510 area is located in the winding having a 01:00:14.14001:00:14.150 temperature difference of delta T 01:00:15.94001:00:15.950 compared with the ambient temperature 01:00:18.21001:00:18.220 this heat has to be distributed as 01:00:21.10001:00:21.110 thermal losses PV T H over the 01:00:23.50001:00:23.510 capacitors surface a and the thermal 01:00:25.72001:00:25.730 resistance beta to the ambient 01:00:27.55001:00:27.560 environment P V T H equals delta T 01:00:41.92001:00:41.930 Beata display style P underscore v 01:00:46.21001:00:46.220 equals delta t c DOTA c do t beta the 01:00:52.26901:00:52.279 thermal resistance beta depends on the 01:00:54.57901:00:54.589 case size of the relevant capacitor and 01:00:56.79901:00:56.809 if applicable on additional cooling 01:00:58.42001:00:58.430 conditions if the internally generated 01:01:02.17001:01:02.180 power losses p VL dissipated by thermal 01:01:05.50001:01:05.510 radiation convection and thermal 01:01:07.39001:01:07.400 conduction to the ambient environment 01:01:09.87001:01:09.880 correspond to the thermal losses PV T H 01:01:12.91001:01:12.920 then a temperature balance between 01:01:14.95001:01:14.960 capacitor temperature and ambient 01:01:17.17001:01:17.180 temperature is given typically the 01:01:19.51001:01:19.520 specified rated value for maximum ripple 01:01:22.35901:01:22.369 current in manufacturers data sheets is 01:01:24.91001:01:24.920 calculated for a heating the capacitor 01:01:27.19001:01:27.200 core cell of 10 degrees Celsius 485 01:01:30.54901:01:30.559 degrees Celsius series 5 degrees Celsius 01:01:33.78901:01:33.799 for 105 degrees Celsius series and 3 01:01:37.18001:01:37.190 degrees Celsius for 125 degrees Celsius 01:01:40.96001:01:40.970 series the rated ripple current of 01:01:44.50001:01:44.51001:01:46.75001:01:46.760 non solid electrolyte corresponds with 01:01:49.08901:01:49.099 the specified lifetime of the capacitor 01:01:51.60901:01:51.619 series this current may flow permanent 01:01:54.94001:01:54.950 over the capacitor up to the maximum 01:01:57.03901:01:57.049 temperature during the specified or 01:01:59.23001:01:59.240 calculated time ripple current lower 01:02:02.55901:02:02.569 than specified or forced cooling length 01:02:04.99001:02:05.000 in the capacitors lifetime the lifetime 01:02:08.74001:02:08.750 of electrolytic capacitors with non 01:02:10.93001:02:10.940 solid electrolyte depends on the 01:02:12.97001:02:12.980 evaporation rate and therefore on the 01:02:15.03901:02:15.049 core temperature of the capacitor with 01:02:17.95001:02:17.960 forced cooling or special positioning of 01:02:20.34901:02:20.359 the capacitor on the PCB the lifetime 01:02:22.99001:02:23.000 can be influenced positively 01:02:24.73001:02:24.740 the ripple current is specified as an 01:02:26.98001:02:26.990 effective RMS value at 100 or 120 Hertz 01:02:31.05901:02:31.069 or at 10 kilohertz at upper category 01:02:33.54901:02:33.559 temperature non sinusoidal ripple 01:02:36.76001:02:36.770 currents have to be analyzed and 01:02:38.62001:02:38.630 separated into the single sinusoidal 01:02:41.01901:02:41.029 frequencies by means of Fourier analysis 01:02:43.77901:02:43.789 and summarized by squared edition of the 01:02:46.15001:02:46.160 single currents 01:02:48.99001:02:49.000 I 01:02:50.60901:02:50.619 ah equals I 1 2 plus I 2 2 plus 01:03:06.67001:03:06.680 I 3 2 + I 01:03:14.62001:03:14.630 and to display style I underscore R 01:03:19.77901:03:19.789 equals s QR t I underscore one carat two 01:03:24.24901:03:24.259 plus i underscore two carat two plus i 01:03:28.32901:03:28.339 underscore three carat two plus i 01:03:31.63001:03:31.640 underscore n parrot to periodically 01:03:35.98001:03:35.990 appearing high current pulses which may 01:03:38.41001:03:38.420 be much higher than the rated ripple 01:03:40.26901:03:40.279 current have to be analyzed in the same 01:03:42.40001:03:42.410 matter because the ESR decreases with 01:03:46.15001:03:46.160 increasing frequencies the ripple 01:03:48.37001:03:48.380 current datasheet value specified at 100 01:03:51.73001:03:51.740 and 120 s of a hertz can be higher at 01:03:54.75901:03:54.769 higher frequencies in cases like this 01:03:58.10901:03:58.119 manufacturers specify correction factors 01:04:01.05901:04:01.069 for ripple current values at higher 01:04:03.03901:04:03.049 frequencies for example the ripple 01:04:06.54901:04:06.559 current at 10 kilohertz can usually be 01:04:08.95001:04:08.960 approximated to be 30 to 40% higher than 01:04:11.92001:04:11.930 the 100 and 120 s value if the ripple 01:04:16.74901:04:16.759 current exceeds the rated value the 01:04:19.21001:04:19.220 corresponding heat generation exceeds 01:04:21.57901:04:21.589 the capacitors temperature limit and may 01:04:23.85901:04:23.869 destroy the internal structure voltage 01:04:26.28901:04:26.299 proof boiling point of the capacitors 01:04:29.03901:04:29.049 then the components tend to 01:04:31.52901:04:31.539 short-circuiting vent opening or 01:04:33.64001:04:33.650 explosion ripple currents higher than 01:04:36.75901:04:36.769 rated values are possible only with 01:04:38.92001:04:38.930 forced cooling 01:04:44.94001:04:44.950 topic charge/discharge stability 01:04:51.74001:04:51.75001:04:54.51001:04:54.520 non solid electrolytes always contain in 01:04:57.32901:04:57.339 addition to the anode foil a cathode 01:04:59.55001:04:59.560 foil that serves as electrical contact 01:05:02.16001:05:02.170 to the electrolyte this cathode foil is 01:05:05.57901:05:05.589 provided with a very thin natural air 01:05:08.13001:05:08.140 originated oxide layer which act also as 01:05:11.06901:05:11.079 a dielectric 01:05:12.07901:05:12.089 thus the capacitor construction forms a 01:05:15.56901:05:15.579 series circuit of two capacitors the 01:05:17.97001:05:17.980 capacitance of the anode foil CA and the 01:05:20.60901:05:20.619 cathode foil CK as described above the 01:05:24.59901:05:24.609 capacitance of the capacitor C cap is 01:05:27.21001:05:27.220 mainly determined by the anode 01:05:28.98001:05:28.990 capacitance CA when the cathode 01:05:31.26001:05:31.270 capacitance CK is approximately 10 times 01:05:34.34901:05:34.359 higher than the anode capacitance CA 01:05:37.84901:05:37.859 aluminium electrolytic capacitors with 01:05:40.62001:05:40.630 non solid electrolytes normally can be 01:05:43.05001:05:43.060 charged up to the rated voltage without 01:05:45.15001:05:45.160 any current limitation this property is 01:05:48.66001:05:48.670 a result of the limited ion movability 01:05:50.81901:05:50.829 in the liquid electrolyte which slows 01:05:53.25001:05:53.260 down the voltage ramp across the 01:05:55.14001:05:55.150 dielectric and the capacitors ESR during 01:05:59.49001:05:59.500 discharging the internal construction of 01:06:01.74001:06:01.750 the capacitor reverses the internal 01:06:03.93001:06:03.940 polarity the cathode gets an anode plus 01:06:07.53001:06:07.540 and changes the current flow direction 01:06:10.19001:06:10.200 two voltages arise over these electrode 01:06:13.55901:06:13.569 in principle the voltage distribution 01:06:16.53001:06:16.540 over both electrodes behaves as the 01:06:18.66001:06:18.670 reciprocal ecv product of each electrode 01:06:21.85901:06:21.869 the design rule of high cathode 01:06:24.63001:06:24.640 capacitance assures that the voltage 01:06:26.84901:06:26.859 appearing over the cathode during 01:06:28.71001:06:28.720 discharge is not higher than roughly 1.5 01:06:31.71001:06:31.720 volts that is its natural air originated 01:06:34.58901:06:34.599 voltage proof no further post forming of 01:06:38.30901:06:38.319 the cathode foil takes place which may 01:06:40.89001:06:40.900 lead to capacitance degradation then the 01:06:44.25001:06:44.260 capacitors are discharged proof topic 01:06:48.66001:06:48.670 current surge 01:06:49.80001:06:49.810 peak or pulse current small diameter 01:06:56.84901:06:56.859 topic leakage current 01:07:02.69001:07:02.700 a characteristic property of 01:07:04.79001:07:04.800 electrolytic capacitors is their leakage 01:07:07.73001:07:07.740 current this DC current is represented 01:07:11.69001:07:11.700 by the resistor our leak in parallel 01:07:13.85001:07:13.860 with the capacitor in the series 01:07:15.65001:07:15.660 equivalent circuit of electrolytic 01:07:17.69001:07:17.700 capacitors and flows if a voltage is 01:07:20.09001:07:20.100 applied the leakage current includes all 01:07:23.75001:07:23.760 weak imperfections of the dielectric 01:07:25.82001:07:25.830 caused by unwanted chemical processes 01:07:28.31001:07:28.320 and mechanical damage and is the DC 01:07:30.59001:07:30.600 current that can pass through the 01:07:32.18001:07:32.190 dielectric after applying a voltage in 01:07:34.55001:07:34.560 correct polarity it depends on the 01:07:37.55001:07:37.560 capacitance value on applied voltage and 01:07:40.25001:07:40.260 temperature of the capacitor on 01:07:42.05001:07:42.060 measuring time on the kind of 01:07:43.91001:07:43.920 electrolyte and on preconditions like 01:07:46.25001:07:46.260 previous storage time without voltage 01:07:48.62001:07:48.630 applied or thermic stress from 01:07:50.51001:07:50.520 soldiering all non solid electrolytic 01:07:53.84001:07:53.850 capacitors needs a recovery time of some 01:07:56.36001:07:56.370 hours after soldiering before measuring 01:07:58.31001:07:58.320 the leakage current non-solid chip 01:08:01.55001:08:01.560 capacitors need a recovery time after 01:08:04.13001:08:04.140 reflow soldering of about 24 hours 01:08:06.50001:08:06.510 leakage current is reduced by applying 01:08:09.20001:08:09.210 operational voltage by self-healing 01:08:11.54001:08:11.550 processors the leakage current drops in 01:08:15.32001:08:15.330 the first minutes after applying DC 01:08:17.60001:08:17.610 voltage in this time the dielectric 01:08:20.78001:08:20.790 oxide layer can repair all weaknesses by 01:08:23.48001:08:23.490 building up new layers in a self-healing 01:08:25.61001:08:25.620 process the time it takes leakage 01:08:28.76001:08:28.770 current to drop generally depends on the 01:08:31.07001:08:31.080 kind of electrolyte solid electrolytes 01:08:34.37001:08:34.380 leakage current drops much faster than 01:08:36.80001:08:36.810 in the case of non solid types but it 01:08:39.23001:08:39.240 remain at a somewhat higher level West 01:08:42.17001:08:42.180 electrolytic capacitors with high water 01:08:44.48001:08:44.490 content electrolytes in the first 01:08:46.58001:08:46.590 minutes generally have higher leakage 01:08:48.71001:08:48.720 current than those with organic 01:08:50.33001:08:50.340 electrolytes but after several minutes 01:08:52.40001:08:52.410 they reach the same level although the 01:08:55.52001:08:55.530 leakage current of electrolytic 01:08:57.38001:08:57.390 capacitors is higher compared with the 01:08:59.51001:08:59.520 current flow over their insulation 01:09:01.34001:09:01.350 resistance at ceramic or film capacitors 01:09:03.50001:09:03.510 the self discharge of modern non-solid 01:09:06.56001:09:06.570 electrolytic capacitors can take several 01:09:09.05001:09:09.060 weeks the leakage current II leak 01:09:12.58001:09:12.590 specification in manufacturers data 01:09:14.90001:09:14.910 sheets refers to the 01:09:16.51901:09:16.529 Tacitus capacitance value CR rated 01:09:19.43001:09:19.440 voltage you're a correlation factor in a 01:09:22.01001:09:22.020 minimum current value for example 01:09:26.14001:09:26.15001:09:27.59901:09:27.609 el e a K equals 0 o 1 a V F you 01:09:46.47901:09:46.489 ah see 01:09:49.64901:09:49.659 ah +3 mu a display style i underscore 01:09:59.01001:09:59.020 mass from leek equals 0 01:10:01.22901:10:01.239 oh one mathram r / v CD OTF cdotu 01:10:05.99001:10:06.000 underscore mathram r CD o TC underscore 01:10:10.11001:10:10.120 mass from R + 3 mass from mu a after a 01:10:15.12001:10:15.130 measuring time of 2 or 5 minutes 01:10:17.28001:10:17.290 depending on the datasheet specification 01:10:19.97901:10:19.989 the measured leakage current value has 01:10:22.29001:10:22.300 to be lower than the calculated value 01:10:24.86001:10:24.870 normally the leakage current is always 01:10:27.54001:10:27.550 lower the longer the capacitor voltage 01:10:29.43001:10:29.440 is applied the leakage current during 01:10:32.85001:10:32.860 operation after for example 1 hour is 01:10:35.72901:10:35.739 the operational leakage current this 01:10:38.82001:10:38.830 value depends strongly on the 01:10:40.70901:10:40.719 manufacturers series characteristics it 01:10:43.50001:10:43.510 could be lower than one 100th of the 01:10:46.22901:10:46.239 specified value the leakage current 01:10:49.37001:10:49.380 depends on the applied voltage in the 01:10:51.95901:10:51.969 ambient temperature the value during 01:10:55.08001:10:55.090 continuous operation at 85 degrees 01:10:57.68901:10:57.699 Celsius is approximately 4 times higher 01:11:00.54001:11:00.550 than at 20 degrees Celsius otherwise the 01:11:04.29001:11:04.300 value is approximately 1/2 reducing the 01:11:07.37901:11:07.389 applied voltage to 70% of the rated 01:11:10.22901:11:10.239 voltage non solid aluminum electrolytic 01:11:12.78001:11:12.790 capacitors that leakage current after an 01:11:15.36001:11:15.370 operation time of for example one hour 01:11:17.87901:11:17.889 remain on a higher level than specified 01:11:20.68901:11:20.699 mostly they have been mechanically 01:11:22.97901:11:22.989 damaged internally due to high 01:11:24.89901:11:24.909 mechanical stress during mounting 01:11:32.12901:11:32.139 topic dielectric absorption so cage 01:11:39.75001:11:39.760 dielectric absorption occurs when a 01:11:42.22001:11:42.230 capacitor that has remained charged for 01:11:44.59001:11:44.600 a long time discharges only in 01:11:46.45001:11:46.460 completely when briefly discharged 01:11:48.90001:11:48.910 although an ideal capacitor would reach 01:11:51.67001:11:51.680 zero volts after discharge real 01:11:54.13001:11:54.140 capacitors develop a small voltage from 01:11:56.77001:11:56.780 time-delayed dipole discharging a 01:11:58.96001:11:58.970 phenomenon that is also called 01:12:00.70001:12:00.710 dielectric relaxation socage or battery 01:12:05.35001:12:05.360 action dielectric absorption may be a 01:12:09.67001:12:09.680 problem in circuits using very small 01:12:11.83001:12:11.840 currents in electronic circuits such as 01:12:14.62001:12:14.630 long time constant integrators or 01:12:16.75001:12:16.760 sample-and-hold circuits dielectric 01:12:20.38001:12:20.390 absorption is not a problem and in most 01:12:22.57001:12:22.580 applications of electrolytic capacitors 01:12:25.21001:12:25.220 supporting power supply lines but 01:12:28.78001:12:28.790 especially for electrolytic capacitors 01:12:31.18001:12:31.190 with high rated voltage the voltage at 01:12:33.52001:12:33.530 the terminals generated by the 01:12:35.14001:12:35.150 dielectric absorption can be a safety 01:12:37.63001:12:37.640 risk to personnel or circuits in order 01:12:41.11001:12:41.120 to prevent shocks most very large 01:12:43.12001:12:43.130 capacitors are shipped with shorting 01:12:45.07001:12:45.080 wires that need to be removed before use 01:12:52.89001:12:52.900 topic reliability lifetime and failure 01:12:57.03001:12:57.040 modes 01:13:01.22001:13:01.23001:13:04.83001:13:04.840 topic reliability failure rate 01:13:11.80001:13:11.810 the reliability prediction of aluminum 01:13:14.50001:13:14.510 electrolytic capacitors is generally 01:13:16.75001:13:16.760 expressed as a failure rate lambda 01:13:18.78001:13:18.790 abbreviated Fitz 01:13:20.38001:13:20.390 failures in time it is a measure of the 01:13:23.47001:13:23.480 number of failures per unit hour during 01:13:25.66001:13:25.670 the time of constant random failures in 01:13:28.09001:13:28.100 the bathtub curve the flat part in the 01:13:31.30001:13:31.310 bathtub curve corresponds with the 01:13:33.37001:13:33.380 calculated lifetime or service life of 01:13:36.07001:13:36.080 non-solid electrolytic capacitors the 01:13:39.49001:13:39.500 failure rate is used to calculate a 01:13:41.62001:13:41.630 survival probability for a desired 01:13:43.81001:13:43.820 lifetime of an electronic circuit in 01:13:46.21001:13:46.220 combination with other participating 01:13:48.46001:13:48.470 components fit is the number of failures 01:13:52.06001:13:52.070 that can be expected in 1 billion 109 01:13:55.48001:13:55.490 component hours of operation at fixed 01:13:58.24001:13:58.250 working conditions eg 1000 components 01:14:01.69001:14:01.700 for 1 million hour or 1 million 01:14:03.58001:14:03.590 components for 1000 hours 1 ppm 1000 01:14:07.87001:14:07.880 hours each during the period of constant 01:14:10.39001:14:10.400 random failures this failure rate model 01:14:13.63001:14:13.640 implicitly assumes the idea of random 01:14:16.63001:14:16.640 failure individual components fail at 01:14:20.14001:14:20.150 random times but at a predictable rate 01:14:22.71001:14:22.720 failures are short circuits open 01:14:25.30001:14:25.310 circuits and degradation failures 01:14:27.58001:14:27.590 exceeding specified limits of electrical 01:14:30.37001:14:30.380 parameters the reciprocal value of fit 01:14:34.12001:14:34.130 is the mtbf the mean time between 01:14:36.42001:14:36.430 failures the standard operating 01:14:39.97001:14:39.980 conditions for the failure rate fitter 01:14:42.19001:14:42.200 40 degrees Celsius and 0.5 your for 01:14:46.69001:14:46.700 other conditions of applied voltage 01:14:48.33001:14:48.340 current load temperature capacitance 01:14:51.67001:14:51.680 value circuit resistance for tantalum 01:14:54.46001:14:54.470 capacitors mechanical influences and 01:14:57.16001:14:57.170 humidity the fit figure can recalculated 01:14:59.32001:14:59.330 with acceleration factors standardized 01:15:01.93001:15:01.940 for industrial or military contexts the 01:15:05.59001:15:05.600 higher the temperature and the applied 01:15:07.39001:15:07.400 voltage the higher the failure rate it 01:15:10.99001:15:11.000 is good to know that for capacitors with 01:15:13.30001:15:13.310 solid electrolytes the failure rate is 01:15:15.61001:15:15.620 often expressed as percent failed 01:15:17.47001:15:17.480 components per thousand hours and 01:15:19.60001:15:19.610 percent 1000h and specified at reference 01:15:23.02001:15:23.030 conditions 85 degrees Celsius 01:15:25.54901:15:25.559 and rated voltage your that is n number 01:15:30.25901:15:30.269 of failed components per 105 hours or in 01:15:33.67901:15:33.689 fit the 10,000 fold value per 109 hours 01:15:37.27901:15:37.289 but for different reference conditions 01:15:39.60901:15:39.619 for these other conditions their percent 01:15:42.94901:15:42.959 I 1000h figure can be recalculated with 01:15:47.59901:15:47.609 acceleration factors standardized for 01:15:50.14901:15:50.159 industrial or military contexts most 01:15:53.95901:15:53.969 modern aluminum electrolytic capacitors 01:15:56.50901:15:56.519 with non solid electrolytes nowadays are 01:15:59.14901:15:59.159 very reliable components with very low 01:16:01.52001:16:01.530 failure rates with predicted life 01:16:03.58901:16:03.599 expectancies of decades under normal 01:16:05.95901:16:05.969 conditions it is best practice to have 01:16:09.43901:16:09.449 electrolytic capacitors pass a post 01:16:11.71901:16:11.729 forming process step after production 01:16:13.90901:16:13.919 similar to a burn in so that early 01:16:16.87901:16:16.889 failures are eliminated during 01:16:19.21901:16:19.229 production the fit values given in data 01:16:22.57901:16:22.589 sheets are calculated from the long time 01:16:25.30901:16:25.319 experience of the manufacturer based on 01:16:28.36901:16:28.379 the lifetime test results typical 01:16:31.84901:16:31.859 reference failure rate values for 01:16:34.36901:16:34.37901:16:36.91901:16:36.929 non solid electrolytes are for low 01:16:39.25901:16:39.269 voltages types 6.3 to 160 volts fit 01:16:44.59901:16:44.609 rates in the range of 1 to 20 fit and 01:16:47.47901:16:47.489 for high voltage types greater than 160 01:16:51.34901:16:51.359 to 550 volts fit rates in the range of 01:16:55.27901:16:55.289 20 to 200 fit field failure rates for 01:16:59.95901:16:59.969 aluminum capacitors are in the range of 01:17:02.41901:17:02.429 0.5 to 25th the data for their failure 01:17:07.66901:17:07.679 rate specification are based on the 01:17:10.63901:17:10.649 results of lifetime testing endurance 01:17:13.48901:17:13.499 testing in addition er field failure 01:17:17.71901:17:17.729 rate is sometimes specified this figures 01:17:21.04901:17:21.059 comes from big customers that noticed 01:17:23.27001:17:23.280 failures in the field out of their 01:17:25.00901:17:25.019 application field failure rates could 01:17:28.36901:17:28.379 have much lower values for aluminum 01:17:31.15901:17:31.169 electrolytic capacitors they are in the 01:17:33.40901:17:33.419 range of 0.5 to 20 fit the field failure 01:17:38.05901:17:38.069 rate values are 01:17:39.20001:17:39.210 in line with the usual orders of 01:17:40.94001:17:40.950 magnitude for electronic components 01:17:48.56001:17:48.570 topic lifetime service life 01:17:55.46901:17:55.47901:17:58.23901:17:58.249 non solid electrolytes have an 01:18:00.12901:18:00.139 exceptional position among electronic 01:18:02.31901:18:02.329 components because they work with an 01:18:04.27001:18:04.280 electrolyte as liquid ingredient the 01:18:07.44901:18:07.459 liquid electrolyte determines the 01:18:09.45901:18:09.469 time-dependent behavior of electrolytic 01:18:11.85901:18:11.869 capacitors they age over time as the 01:18:14.73901:18:14.749 electrolyte evaporates this also implies 01:18:17.91901:18:17.929 that there is a sharp decline in useful 01:18:19.98901:18:19.999 lifespan with increasing temperature as 01:18:22.66001:18:22.670 a rule of thumb every 10 degrees rise 01:18:25.95901:18:25.969 haves the useful lifespan this very slow 01:18:29.73901:18:29.749 drying out of the electrolyte depends on 01:18:32.19901:18:32.209 the series construction ambient 01:18:34.27001:18:34.280 temperature voltage and ripple current 01:18:36.66901:18:36.679 load lowering the electrolyte over time 01:18:39.87901:18:39.889 influences the capacitance impedance and 01:18:42.85001:18:42.860 ESR of the capacitors the capacitance 01:18:46.33001:18:46.340 decreases an impedance and ESR increases 01:18:49.35901:18:49.369 with decreasing amounts of electrolyte 01:18:51.68901:18:51.699 the leakage current decreases because 01:18:54.52001:18:54.530 all weaknesses are healed after the long 01:18:56.67901:18:56.689 forming time in contrast to electrolytic 01:19:00.45901:19:00.469 capacitors with solid electrolytes wet 01:19:04.08001:19:04.090 electrolytic capacitors have an 01:19:06.56901:19:06.579 end-of-life when the components reach 01:19:09.91001:19:09.920 specified maximum changes of capacitance 01:19:12.85001:19:12.860 impedance or ESR the time period to 01:19:16.83901:19:16.849 their end-of-life is called their 01:19:19.97901:19:19.989 lifetime useful life load life or 01:19:26.06901:19:26.079 service life it represents the time of 01:19:30.18901:19:30.199 constant failure rate in the failure 01:19:32.25901:19:32.269 rate bathtub curve under normal ambient 01:19:35.97901:19:35.989 conditions electrolytic capacitors can 01:19:38.52901:19:38.539 have more than a fifteen year lifetime 01:19:40.33001:19:40.340 but this can be limited depending on the 01:19:42.93901:19:42.949 degradation behavior of the rubber bung 01:19:45.00901:19:45.019 which is not typically aged during 01:19:47.04901:19:47.059 lifetime testing this rating is tested 01:19:50.52901:19:50.539 with an accelerated aging test called an 01:19:53.06901:19:53.079 endurance test according to IEC 603 8 4 01:19:58.50901:19:58.519 4 1 with rated voltage at the upper 01:20:01.44901:20:01.459 category temperature one of the 01:20:04.02901:20:04.039 challenges with this aging test is the 01:20:06.27901:20:06.289 time required to extract any meaningful 01:20:08.67901:20:08.689 result 01:20:09.66001:20:09.670 in response to demands for long life 01:20:12.45001:20:12.460 high temperature performance from 01:20:14.67001:20:14.680 automotive and green energy applications 01:20:16.67001:20:16.680 solar microbe inverters LEDs wind 01:20:20.43001:20:20.440 turbines etc some capacitors require 01:20:23.61001:20:23.620 more than a year's worth of testing 01:20:25.62001:20:25.630 10,000 hours before they can be 01:20:27.99001:20:28.000 qualified due to this limitation there 01:20:31.41001:20:31.420 has been increasing interest in 01:20:33.09001:20:33.100 methodologies to accelerate the test in 01:20:35.61001:20:35.620 a manner that still produces relevant 01:20:37.68001:20:37.690 results the graph at right show the 01:20:41.10001:20:41.110 behavior of the electrical parameters of 01:20:43.44001:20:43.45001:20:45.69001:20:45.700 non solid electrolytes due to 01:20:47.64001:20:47.650 evaporation of the electrolyte in a 2008 01:20:50.64001:20:50.650 endurance test at 105 degrees Celsius 01:20:54.38001:20:54.390 the process of drying out is also 01:20:57.42001:20:57.430 detectable by weight loss after this 01:21:00.96001:21:00.970 endurance test the specified parameter 01:21:03.66001:21:03.670 limits to pass the tests are on the one 01:21:05.85001:21:05.860 hand no total failures short circuit 01:21:08.97001:21:08.980 open circuit and on the other hand not 01:21:11.79001:21:11.800 reaching degradation failure a reduction 01:21:14.37001:21:14.380 of capacitance over 30% and an increase 01:21:17.25001:21:17.260 of the ESR impedance or loss factor by 01:21:19.98001:21:19.990 more than a factor of 3 compared to the 01:21:22.35001:21:22.360 initial value parameters of the tested 01:21:25.53001:21:25.540 component beyond these limits can be 01:21:27.54001:21:27.550 counted as evidence of degradation 01:21:29.16001:21:29.170 failure the testing time and temperature 01:21:33.03001:21:33.040 depend on the tested series that is the 01:21:36.33001:21:36.340 reason for the many different lifetime 01:21:38.48001:21:38.490 specifications in the data sheets of 01:21:40.77001:21:40.780 manufacturers which are given in the 01:21:42.84001:21:42.850 form of a time temperature indication 01:21:45.15001:21:45.160 for example 2000 H 85 degrees Celsius 01:21:49.58001:21:49.590 2008 105 degrees Celsius 5000 H 105 01:21:55.68001:21:55.690 degrees Celsius 2008 125 degrees Celsius 01:22:01.16001:22:01.170 this figure specifies the minimum 01:22:03.69001:22:03.700 lifetime of the capacitors of a series 01:22:06.30001:22:06.310 when exposed at the maximum temperature 01:22:08.34001:22:08.350 with applied rated voltage referring to 01:22:12.48001:22:12.490 the endurance test this specification 01:22:14.67001:22:14.680 does not include the capacitors being 01:22:17.22001:22:17.230 loaded with the rated ripple current 01:22:19.08001:22:19.090 value but the additional internal heat 01:22:22.23001:22:22.240 of three to 10 01:22:23.49001:22:23.500 a depending on the series which is 01:22:25.68001:22:25.690 generated by the ripple current is 01:22:27.63001:22:27.640 usually taken into account by the 01:22:29.49001:22:29.500 manufacturer due to safety margins when 01:22:32.22001:22:32.230 interpreting the results of its 01:22:33.81001:22:33.820 endurance tests a test with an actual 01:22:37.23001:22:37.240 applied ripple current is affordable for 01:22:39.45001:22:39.460 any manufacturer a capacitors lifetime 01:22:43.44001:22:43.450 for different operational conditions can 01:22:45.90001:22:45.910 be estimated using special formulas or 01:22:48.48001:22:48.490 graphs specified in the data sheets of 01:22:50.85001:22:50.860 serious manufacturers they use different 01:22:54.33001:22:54.340 ways achieve the specification some 01:22:56.76001:22:56.770 provide special formulas others specify 01:22:59.55001:22:59.560 their capacitor lifetime calculation 01:23:01.77001:23:01.780 with graphs that take into account the 01:23:03.87001:23:03.880 influence of applied voltage the basic 01:23:07.20001:23:07.210 principle for calculating the time under 01:23:09.45001:23:09.460 operational conditions is the so called 01:23:11.69001:23:11.700 10-degree rule this rule is also well 01:23:14.55001:23:14.560 known as the Arrhenius rule it 01:23:17.06001:23:17.070 characterizes the change of thermic 01:23:19.26001:23:19.270 reaction speed for every 10 degrees 01:23:22.11001:23:22.120 Celsius lower temperature evaporation 01:23:24.90001:23:24.910 halves that means for every 10 degrees 01:23:27.81001:23:27.820 Celsius lower temperature the lifetime 01:23:30.27001:23:30.280 of capacitors doubles 01:23:32.06001:23:32.070 L 01:23:34.35901:23:34.36901:23:36.44001:23:36.450 quills 01:23:37.96001:23:37.97001:23:39.50001:23:39.510 spec to t0 minus T a 10 displaced I'll 01:23:53.18001:23:53.190 I'll underscore X equals l underscore 01:23:56.00001:23:56.010 text spec C do T to caret frac T 01:24:00.08001:24:00.090 underscore 0 T underscore R 10 01:24:03.64001:24:03.650 Lux equals lifetime to be estimated 01:24:07.81001:24:07.820 LSP EC equals specified lifetime useful 01:24:11.87001:24:11.880 life load life service life T 0 equals 01:24:16.79001:24:16.800 upper category temperature degree C thar 01:24:20.75001:24:20.760 equals temperature degree C of the case 01:24:23.54001:24:23.550 or ambient temperature near the 01:24:25.45901:24:25.469 capacitor e4 lifetime specification of 01:24:28.22001:24:28.230 an electrolytic capacitor is for example 01:24:31.20901:24:31.219 2008 105 degrees Celsius the capacitors 01:24:35.72001:24:35.730 lifetime at 45 degrees Celsius can be 01:24:38.97901:24:38.989 calculated as 128 thousand hours roughly 01:24:44.56901:24:44.579 15 years by using the 10 degree rule 01:24:47.81001:24:47.820 although the result of the longer 01:24:50.39001:24:50.400 lifetime at lower temperatures comes 01:24:52.49001:24:52.500 from a mathematical calculation the 01:24:54.89001:24:54.900 result is always an estimation of the 01:24:56.93001:24:56.940 expected behavior of a group of similar 01:24:59.25901:24:59.269 components the lifetime of electrolytic 01:25:03.25901:25:03.269 capacitors with non solid electrolytes 01:25:05.56901:25:05.579 depends on the evaporations rate and 01:25:08.00001:25:08.010 therefore on the core temperature of the 01:25:09.89001:25:09.900 capacitor this core temperature on the 01:25:13.04001:25:13.050 other hand depends on the ripple current 01:25:14.83901:25:14.849 load using the 10 degree rule with the 01:25:18.52901:25:18.539 capacitor case temperature gives a good 01:25:20.77901:25:20.789 approach to operational conditions in 01:25:23.99001:25:24.000 case of higher ripple currents the 01:25:26.18001:25:26.190 lifetime could be influenced positively 01:25:27.95001:25:27.960 with for schooling near the end of the 01:25:31.64001:25:31.650 capacitors lifetime degradation failure 01:25:34.16001:25:34.170 begins to appear at the same time the 01:25:37.37001:25:37.380 range of the constant failure rate ends 01:25:39.91001:25:39.920 but even after exceeding the capacitors 01:25:43.06901:25:43.079 specified end of life the electronic 01:25:45.62001:25:45.630 circuit is not in immediate danger only 01:25:48.04901:25:48.059 the functionality of the capacitor is 01:25:50.45001:25:50.460 reduced with today's high levels of 01:25:53.50901:25:53.519 purity in the manufacture of 01:25:55.25001:25:55.260 electrolytic capacitors it is not to be 01:25:57.68001:25:57.690 expected that short circuits occur after 01:26:00.31901:26:00.329 the end-of-life point with progressive 01:26:02.35901:26:02.369 of a per 01:26:02.89901:26:02.909 combined with parameter degradation 01:26:10.45001:26:10.460 topic failure modes 01:26:16.32901:26:16.33901:26:19.00001:26:19.010 non solid electrolytes have in terms of 01:26:21.60901:26:21.619 quality a relatively negative public 01:26:24.04001:26:24.050 image this is contrary to industrial 01:26:27.30901:26:27.319 experience where electrolytic capacitors 01:26:30.06901:26:30.079 are considered to be reliable components 01:26:32.40901:26:32.419 if used within the specified 01:26:34.10901:26:34.119 specifications during the calculated 01:26:36.42901:26:36.439 lifetime the negative public image might 01:26:39.79001:26:39.800 be among other reasons because failed 01:26:42.09901:26:42.109 electrolytic capacitors in devices are 01:26:44.64901:26:44.659 easily and immediately visible this is 01:26:47.55901:26:47.569 exceptional and not the case with other 01:26:49.56901:26:49.579 electronic components as with any 01:26:53.04901:26:53.059 industrial product specific causes of 01:26:55.89901:26:55.909 failure modes are known for aluminum 01:26:57.93901:26:57.94901:27:00.30901:27:00.319 electrolytes they can be differentiated 01:27:03.06901:27:03.079 in failures causes by capacitor 01:27:05.88901:27:05.899 development and production by device 01:27:08.13901:27:08.149 production by capacitor application or 01:27:10.89901:27:10.909 by external influences during use the 01:27:13.59901:27:13.609 capacitor manufacturing industries can 01:27:16.00001:27:16.010 only influence the first failure mode 01:27:18.29901:27:18.309 most manufacturers have had 01:27:20.85901:27:20.869 well-structured quality control 01:27:22.83901:27:22.849 departments for decades supervising all 01:27:25.54001:27:25.550 development and manufacturing steps 01:27:28.29001:27:28.300 failure mode flowcharts demonstrate this 01:27:31.65901:27:31.669 however a typical physically or 01:27:34.47901:27:34.489 chemically caused major failure mode 01:27:36.66901:27:36.679 during application like field 01:27:39.27001:27:39.280 crystallization for tantalum capacitors 01:27:42.81901:27:42.829 is not known for non solid aluminium 01:27:45.18901:27:45.19901:27:51.87001:27:51.880 topic capacitor behavior after storage 01:27:55.77001:27:55.780 or disease 01:28:00.30901:28:00.319 in many quarters electrolytic capacitors 01:28:03.36901:28:03.379 are considered very unreliable 01:28:04.88901:28:04.899 components when compared to other 01:28:06.93901:28:06.949 passives this is partly a function of 01:28:10.20901:28:10.219 the history of these components 01:28:12.32901:28:12.339 capacitors manufactured during and 01:28:14.97901:28:14.989 before World War two sometimes suffered 01:28:17.37901:28:17.389 from contamination during manual 01:28:19.35901:28:19.369 manufacturing and in particular chlorine 01:28:21.96901:28:21.979 salts were often the reason for 01:28:23.70901:28:23.719 corrosive processes leading to high 01:28:25.75001:28:25.760 leakage currents chlorine acts on 01:28:28.86901:28:28.879 aluminum as a catalyst for the formation 01:28:31.02901:28:31.039 of unstable oxide without becoming 01:28:33.15901:28:33.169 chemically bound itself after World War 01:28:37.05901:28:37.069 2 this problem was known but the 01:28:39.33901:28:39.349 measuring equipment was not accurate 01:28:40.98901:28:40.999 enough to detect chlorine in very low 01:28:43.53901:28:43.549 ppm concentration the situation improved 01:28:47.61901:28:47.629 over the next 20 years and the 01:28:49.53901:28:49.549 capacitors became good enough for longer 01:28:51.87901:28:51.889 life applications this led in turn to a 01:28:55.41901:28:55.429 previously are noticed water driven 01:28:57.48901:28:57.499 corrosion which weakens the stable 01:28:59.77001:28:59.780 dielectric oxide layer during storage or 01:29:02.52901:29:02.539 disease 01:29:03.30901:29:03.319 this leads to high leakage currents 01:29:06.18901:29:06.199 after storage most of the electrolytes 01:29:09.00901:29:09.019 in that time contain water and many of 01:29:11.58901:29:11.599 the capacitors reach their end-of-life 01:29:13.47901:29:13.489 by drying out water driven corrosion was 01:29:17.43901:29:17.449 the reason for recommended precondition 01:29:19.71901:29:19.729 instructions the first solution in the 01:29:23.54901:29:23.559 1970s was the development of water free 01:29:26.52901:29:26.539 electrolyte systems based on organic 01:29:28.71901:29:28.729 solvents there are advantages among 01:29:32.10901:29:32.119 other things were lower leakage currents 01:29:34.35901:29:34.369 and nearly unlimited shelf life but now 01:29:37.65901:29:37.669 another problem was observed the growing 01:29:40.44901:29:40.459 mass production with automatic insertion 01:29:42.72901:29:42.739 machines requires a washing of the PCBs 01:29:45.69901:29:45.709 after sole during the cleaning solutions 01:29:49.08901:29:49.099 contain chloro alkanes CFC agents these 01:29:53.25901:29:53.269 halogens solutions sometimes permeate 01:29:56.02001:29:56.030 the ceiling of the capacitors and start 01:29:58.20901:29:58.219 chlorine corrosion again there was a 01:30:01.11901:30:01.129 leakage current problem the use of CFCs 01:30:05.28901:30:05.299 as solvents for dry cleaning have been 01:30:07.62901:30:07.639 phased out for example by the IPPC 01:30:10.53901:30:10.549 directive on greenhouse gases in 1995 01:30:14.11001:30:14.120 or and by the volatile organic compounds 01:30:16.66001:30:16.670 vo C directive of the EU in 1997 in the 01:30:21.37001:30:21.380 meantime electrolytic systems have been 01:30:23.98001:30:23.990 developed with additives to inhibit the 01:30:26.11001:30:26.120 reaction between an Adak aluminum oxide 01:30:28.60001:30:28.610 and water which solve most of the high 01:30:30.94001:30:30.950 leakage current problems after storage 01:30:33.28001:30:33.290 the ability of non solid aluminum 01:30:35.56001:30:35.570 electrolytic capacitors to have a stable 01:30:37.87001:30:37.880 behavior during longer storage times can 01:30:40.60001:30:40.610 be tested by using an accelerating test 01:30:43.09001:30:43.100 of storage the capacitors at its upper 01:30:45.19001:30:45.200 category temperature for a certain 01:30:47.26001:30:47.270 period usually 1000 hours without 01:30:49.84001:30:49.850 voltage applied this shelf-life test is 01:30:54.73001:30:54.740 a good indicator for an inert chemically 01:30:57.46001:30:57.470 behavior of the electrolytic system 01:30:59.71001:30:59.720 against the dielectric aluminum oxide 01:31:02.02001:31:02.030 layer because all chemical reactions are 01:31:04.48001:31:04.490 accelerated by high temperatures nearly 01:31:07.75001:31:07.760 all today's series of capacitors fulfil 01:31:10.75001:31:10.760 the 1000 hours shelf life test which is 01:31:13.78001:31:13.790 equivalent to a minimum 5 years of 01:31:15.94001:31:15.950 storage at room temperature 01:31:17.88001:31:17.890 modern electrolytic capacitors don't 01:31:20.74001:31:20.750 need preconditioning after such storage 01:31:22.90001:31:22.910 however many capacitor series are 01:31:26.23001:31:26.240 specified only for two years storage 01:31:28.63001:31:28.640 time but the limit is set by oxidation 01:31:31.03001:31:31.040 of terminals and resulting solderability 01:31:33.46001:31:33.470 problems for restoring antique radio 01:31:37.39001:31:37.400 equipment using older electrolytic 01:31:39.64001:31:39.650 capacitors built in the 1970s or earlier 01:31:43.47001:31:43.480 preconditioning is often recommended for 01:31:47.08001:31:47.090 this purpose the rated voltage is 01:31:49.39001:31:49.400 applied to the capacitor via a series 01:31:51.73001:31:51.740 resistance of approximately 1 kilo ohm 01:31:54.13001:31:54.140 for a period of one hour applying a 01:31:57.40001:31:57.410 voltage via a safety resistor repairs 01:31:59.86001:31:59.870 the oxide layer by self-healing but 01:32:02.53001:32:02.540 slowly minimizing internal heating if 01:32:05.85001:32:05.860 capacitors still don't meet the leakage 01:32:08.38001:32:08.390 current requirements after 01:32:09.78001:32:09.790 preconditioning it may be an indication 01:32:12.10001:32:12.110 of permanent damage 01:32:18.86901:32:18.879 topic additional information 01:32:25.27001:32:25.28001:32:28.79001:32:28.800 topic capacitor symbols 01:32:34.96001:32:34.97001:32:38.51001:32:38.520 topic parallel connection 01:32:44.66001:32:44.670 smaller or low-voltage aluminum 01:32:47.20901:32:47.219 electrolytic capacitors may be connected 01:32:49.72901:32:49.739 in parallel without any safety 01:32:51.43901:32:51.449 correction action large sizes capacitors 01:32:55.39901:32:55.409 especially large sizes and high voltage 01:32:57.74001:32:57.750 types should be individually guarded 01:33:00.37901:33:00.389 against sudden energy charge of the 01:33:02.24001:33:02.250 whole capacitor bank due to a failed 01:33:04.28001:33:04.290 specimen 01:33:06.60001:33:06.61001:33:10.04901:33:10.059 topic series connection 01:33:16.09001:33:16.100 some applications like AC AC converters 01:33:19.75001:33:19.760 with DC link for frequency controls in 01:33:22.51001:33:22.520 three-phase grids need higher voltages 01:33:24.88001:33:24.890 than electrolytic capacitors usually 01:33:27.13001:33:27.140 offer for such applications electrolytic 01:33:30.67001:33:30.680 capacitors can be connected in series 01:33:32.83001:33:32.840 for increased voltage withstanding 01:33:35.11001:33:35.120 capability during charging the voltage 01:33:38.74001:33:38.750 across each of the capacitors connected 01:33:40.57001:33:40.580 in series is proportional to the inverse 01:33:43.27001:33:43.280 of the individual capacitors leakage 01:33:45.55001:33:45.560 current since every capacitor differs 01:33:48.85001:33:48.860 somewhat in individual leakage currents 01:33:51.13001:33:51.140 the capacitors with a higher leakage 01:33:53.26001:33:53.270 current will get less voltage the 01:33:56.14001:33:56.150 voltage balanced over the series 01:33:58.15001:33:58.160 connected capacitors is not symmetrical 01:34:00.67001:34:00.680 passive or active voltage balance has to 01:34:03.67001:34:03.680 be provided in order to stabilize the 01:34:06.07001:34:06.080 voltage over each individual capacitor 01:34:10.08001:34:10.09001:34:13.52001:34:13.530 topic imprinted markings 01:34:20.05001:34:20.060 electrolytic capacitors like most other 01:34:22.93901:34:22.949 electronic components have imprinted 01:34:25.22001:34:25.230 markings to indicate the manufacturer 01:34:27.80001:34:27.810 the type the electrical and thermal 01:34:29.75001:34:29.760 characteristics and the date of 01:34:31.93901:34:31.949 manufacture in the ideal case if they 01:34:35.47901:34:35.489 are large enough the capacitor should be 01:34:37.49001:34:37.500 marked with manufacturer's name or 01:34:40.49001:34:40.500 trademark manufacturers type designation 01:34:45.22001:34:45.230 polarity of the terminations for 01:34:47.45001:34:47.460 polarized capacitors rated capacitance 01:34:52.41901:34:52.429 tolerance on rated capacitance rated 01:34:56.66001:34:56.670 voltage and nature of supply AC or DC 01:35:00.72901:35:00.739 climatic category or rated temperature 01:35:04.20901:35:04.219 year and month or week of manufacture 01:35:07.60901:35:07.619 smaller capacitors use a shorthand 01:35:09.80001:35:09.810 notation to display all the relevant 01:35:11.99001:35:12.000 information in the limited space 01:35:13.87901:35:13.889 available the most commonly used format 01:35:17.33001:35:17.340 is X Y Zed K M volts V where X Y Z 01:35:21.32001:35:21.330 represents the capacitance in micro F 01:35:23.87001:35:23.880 the letters K or M indicate the 01:35:26.20901:35:26.219 tolerance plus or minus 10% and plus or 01:35:29.51001:35:29.520 minus 20% respectively and volts V 01:35:32.57001:35:32.580 represents the rated voltage example 01:35:37.60001:35:37.610 a capacitor with the following text on 01:35:39.85001:35:39.860 its body 10m 25 has a capacitance of 10 01:35:43.57001:35:43.580 microfarads tolerance k equals plus or 01:35:46.69001:35:46.700 minus 10% with a rated voltage of 25 V 01:35:50.23001:35:50.240 capacitance tolerance and date of 01:35:52.63001:35:52.640 manufacture can also be identified with 01:35:55.24001:35:55.250 a short code according to IEC 60,000 01:36:01.29001:36:01.300 the rated capacitance micro farad's 01:36:05.46001:36:05.470 micro 47 01:36:11.55001:36:11.560 topic 0.47 microfarads for micro seven 01:36:22.35901:36:22.369 4.7 microfarads 47 micro equals 47 micro 01:36:27.82901:36:27.839 fthe date of manufacture is often 01:36:30.55901:36:30.569 printed in accordance with international 01:36:32.02901:36:32.039 standards in abbreviated form version 1 01:36:36.79901:36:36.809 coding with year per week numeral code 01:36:39.63901:36:39.649 1208 is 2012 week number 8 01:36:46.64001:36:46.650 version two coding with year code per 01:36:49.40001:36:49.410 month code year code are 01:36:55.91901:36:55.929 topic 2003 s equals 2004 tea 01:37:08.33001:37:08.340 2005 you 01:37:14.58001:37:14.590 topic 2006 thee 01:37:23.50001:37:23.510 2007 W 01:37:29.83001:37:29.840 topic 2008 01:37:32.83001:37:32.84001:37:38.68001:37:38.690 2009 a 01:37:44.77901:37:44.789 topic 2010 be 01:37:52.55001:37:52.560 2011 see 01:37:58.74001:37:58.750 topic 2012 D 01:38:06.69001:38:06.700 2013 II 01:38:12.76001:38:12.770 topic 2014 F 01:38:21.05001:38:21.060 20:15 etc months code 1 to 9 equals Jan 01:38:29.45901:38:29.469 - Sept o 01:38:31.82001:38:31.830 equals October n 01:38:38.53001:38:38.540 topic november d 01:38:45.83001:38:45.840 December c5 is then 2012 May 01:38:56.58001:38:56.590 topic polarity marking 01:39:02.64001:39:02.650 polarity marking for non solid and solid 01:39:05.64001:39:05.65001:39:08.51001:39:08.52001:39:11.22001:39:11.230 non solid electrolyte have a polarity 01:39:13.32001:39:13.330 marking at the cathode minus side 01:39:16.88001:39:16.89001:39:19.59001:39:19.600 solid electrolyte have a polarity 01:39:21.54001:39:21.550 marking at the anode plus side SMD style 01:39:26.25001:39:26.26001:39:28.74001:39:28.750 electrolyte vertical chips v chips have 01:39:31.89001:39:31.900 a colored filled half circle or a minus 01:39:34.32001:39:34.330 bar on the top case side visible to 01:39:36.54001:39:36.550 indicate the minus terminal side 01:39:39.23001:39:39.240 additionally the insulating plate under 01:39:42.03001:39:42.040 the capacitor body uses two skewed edges 01:39:44.76001:39:44.770 to indicate that the negative terminal 01:39:46.80001:39:46.810 is on the compliment position radial or 01:39:50.31001:39:50.320 single ended electrolytic capacitor 01:39:52.71001:39:52.720 Stiles have a bar across the side of the 01:39:55.02001:39:55.030 capacitor to indicate the negative 01:39:57.06001:39:57.070 terminal side and the negative terminal 01:39:59.22001:39:59.230 LED is shorter than the positive 01:40:00.99001:40:01.000 terminal lead axial electrolytic 01:40:04.89001:40:04.900 capacitor Stiles have a bar across or 01:40:07.35001:40:07.360 around the case pointing to the negative 01:40:09.51001:40:09.520 lead end to indicate the negative 01:40:11.52001:40:11.530 terminal the positive terminal of the 01:40:14.49001:40:14.500 capacitor is on the side of the ceiling 01:40:16.85001:40:16.860 the negative terminal LED is shorter 01:40:19.95001:40:19.960 than the positive terminal lead on a 01:40:22.67001:40:22.680 printed circuit board it is customary to 01:40:25.77001:40:25.780 indicate the correct orientation by 01:40:28.02001:40:28.030 using a square through-hole pad for the 01:40:30.27001:40:30.280 positive lead and a round pad for the 01:40:32.37001:40:32.380 negative one 01:40:38.23901:40:38.249 topic standardization 01:40:44.29001:40:44.300 the standardization for all electrical 01:40:47.20001:40:47.210 electronic components and related 01:40:49.45001:40:49.460 technologies follows the rules given by 01:40:51.97001:40:51.980 the International Electrotechnical 01:40:53.10901:40:53.119 Commission IEC a non-profit 01:40:56.29001:40:56.300 non-governmental international standards 01:40:58.83901:40:58.849 organization the definition of the 01:41:01.87001:41:01.880 characteristics and the procedure of the 01:41:04.02901:41:04.039 test methods for capacitors for use in 01:41:06.52001:41:06.530 electronic equipment are set out in the 01:41:08.77001:41:08.780 generic specification IEC and 60,000 384 01:41:15.00901:41:15.019 - 1 fixed capacitors for use in 01:41:18.33901:41:18.349 electronic equipment the tests and 01:41:20.37901:41:20.389 requirements to be met by aluminum 01:41:22.45001:41:22.460 electrolytic capacitors for use in 01:41:24.70001:41:24.710 electronic equipment for approval as 01:41:26.91901:41:26.929 standardized types are set out in the 01:41:29.10901:41:29.119 following sectional specifications IEC 01:41:33.18901:41:33.199 and 60,000 384 - 3 surface mount fixed 01:41:38.97901:41:38.989 tantalum electrolytic capacitors with 01:41:41.20001:41:41.210 manganese dioxide solid electrolyte IEC 01:41:45.60901:41:45.619 and 60000 384 - 4 aluminium electrolytic 01:41:50.97001:41:50.980 capacitors with solid manganese 4 oxide 01:41:54.10001:41:54.110 and non solid electrolyte IEC and 60000 01:41:59.70001:41:59.710 384 - 18 fixed aluminium electrolytic 01:42:03.97001:42:03.980 surface mount capacitors with solid 01:42:06.54901:42:06.559 manganese 4 oxide and non solid 01:42:09.12901:42:09.139 electrolyte IEC and 60000 384 - 25 01:42:15.98901:42:15.999 surface mount fixed aluminium 01:42:18.37001:42:18.380 electrolytic capacitors with conductive 01:42:20.73901:42:20.749 polymer solid electrolyte IEC and 60000 01:42:25.95001:42:25.960 384 - 26 fixed aluminium electrolytic 01:42:30.37001:42:30.380 capacitors with conductive polymer solid 01:42:33.06901:42:33.079 electrolyte 01:42:38.16901:42:38.179 topic applications and market 01:42:44.97901:42:44.98901:42:48.56001:42:48.570 topic applications 01:42:54.36001:42:54.370 typical applications of aluminum 01:42:56.85001:42:56.86001:42:59.28001:42:59.290 electrolyte our input and output 01:43:02.46001:43:02.470 decoupling capacitors for smoothing and 01:43:04.86001:43:04.870 filtering in AC power supplies and 01:43:07.23001:43:07.240 switched-mode power supplies as well as 01:43:09.66001:43:09.670 in DC DC convertors DC link capacitors 01:43:14.61001:43:14.620 in AC AC converters for variable 01:43:17.43001:43:17.440 frequency drive and frequency changes as 01:43:20.28001:43:20.290 well as in uninterruptible power 01:43:21.75001:43:21.760 supplies correction capacitors for power 01:43:25.68001:43:25.690 factor correction energy storage for 01:43:29.19001:43:29.200 airbags photo flash devices civil 01:43:32.04001:43:32.050 detonators 01:43:33.32001:43:33.330 motor start capacitors for AC motors 01:43:37.49001:43:37.500 bipolar capacitors for audio signal 01:43:40.38001:43:40.390 coupling flash capacitor for camera 01:43:43.65001:43:43.660 flashes 01:43:48.37001:43:48.380 topic advantages and disadvantages 01:43:55.65901:43:55.669 advantages inexpensive capacitors with 01:43:59.62901:43:59.639 high capacitance values for filtering 01:44:01.90901:44:01.919 lower frequencies higher energy density 01:44:05.20901:44:05.219 than film capacitors and ceramic 01:44:07.87901:44:07.889 capacitors higher power density than 01:44:11.62901:44:11.639 super capacitors no peak current 01:44:15.08001:44:15.090 limitation required impossible to 01:44:18.37901:44:18.389 transience very great diversification in 01:44:22.33901:44:22.349 styles series with tailored lifetimes 01:44:24.97901:44:24.989 temperatures and electrical parameters 01:44:28.20901:44:28.219 many manufacturers disadvantages limited 01:44:32.83901:44:32.849 lifetime due to evaporation relatively 01:44:36.56001:44:36.570 poor ESR and Zed behavior at very low 01:44:39.29001:44:39.300 temperatures sensitive to mechanical 01:44:42.22901:44:42.239 stress sensitive to contamination with 01:44:46.31001:44:46.320 halogen aids polarized application 01:44:53.89001:44:53.900 Topic market 01:44:59.26001:44:59.270 the market for aluminum electrolytic 01:45:01.54001:45:01.550 capacitors in 2010 was around three 01:45:04.48001:45:04.490 point nine billion dollars approximately 01:45:06.55001:45:06.560 two point nine billion euros about 22% 01:45:10.24001:45:10.250 of the value of the total capacitor 01:45:12.73001:45:12.740 market of approximately eighteen billion 01:45:14.83001:45:14.840 dollars 2008 in number of pieces these 01:45:19.09001:45:19.100 capacitors cover about 6% of the total 01:45:21.93001:45:21.940 capacitor market of some 70 to 80 01:45:24.82001:45:24.830 billion pieces 01:45:27.81001:45:27.820 equals equals equals manufacturers and 01:45:30.78001:45:30.790 products
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