Talk:Tantalum capacitor

Latest comment: 1 year ago by 162.18.172.11 in topic MnO2 self healing mechanism image

Untitled edit

"Their effective series resistance (ESR) is quite high when compared to aluminium electrolytics" I believe this is incorrect, does anyone have a recent source relating to this? Bobosoft (talk) 02:24, 1 October 2009 (UTC)Reply

Here are some datasheets: I picked relatively standard 100uF caps of each type, for the same 6.3V rating:

  http://uk.farnell.com/rubycon/6-3zlg100mefc6-3x7/capacitor-100uf-6-3v/dp/1278842
  http://uk.farnell.com/kemet/t350h107k006at/capacitor-case-h-100uf-6-3v/dp/1457594

It seems to be the case that the tants can get more capacitance in a given volume. But for a given capacitance, the electrolytic is usually 10x better (lower) on ESR than the tantalum. — Preceding unsigned comment added by 87.194.171.29 (talk) 20:27, 30 July 2012 (UTC)Reply

This page says "All tantalum capacitors are polarized devices", but Types_of_capacitor says "Available in both polarized and unpolarized varieties". Which is right? CLandau (talk) 17:18, 11 October 2010 (UTC)Reply

There are unpolarized Ta capacitors. Amended this article. Materialscientist (talk) 23:53, 11 October 2010 (UTC)Reply

Tantalums are NOT the most expensive capacitors. If the comparison is made in terms of cost per CV (energy capacity), then glass capacitors are far more expensive, and if the comparison is per unit, EDLC and film types come in much higher priced packages than the largest tantalums. (Disregarding "boutique" capacitors.) — Preceding unsigned comment added by 173.48.205.101 (talk) 00:53, 7 January 2014 (UTC)Reply

What is the significance of the TAG and TAP designations edit

As above - can't find any description anywhere (even google !) of the significance of these type designations for tantalum capacitors.

210.54.213.151 (talk) 22:55, 26 January 2014 (UTC) Geoff Wood geoff@geoffwood.orgReply

voltage ratings edit

Given how easy it is to explode a tantalum cap, it would be useful to have a guide here as to the acceptable voltages.

Eg if I have a 5V power supply, can I use a 6.3V capacitor, and be confident that any spike below 12V will not harm it? Or is this flirting with disaster? — Preceding unsigned comment added by 87.194.171.29 (talk) 13:48, 7 March 2014 (UTC)Reply

This is not only flirting. An older rule of thumb says 50 % voltage derating for the highest voltage you expects and dont forget the protection resistance 3 Ohm per Volt in series to the capacitor. Maybe the remaining ripple voltage is too high - take an aluminum electrolytic capacitor 6.3 V. No resistance required --Elcap (talk) 15:16, 7 March 2014 (UTC)Reply

I was looking up a related issue and found this recommendation of derating voltage 50% and the 3 Ω/V series resistance. The article lists references 66 and 67 for this. Reference 66 is actually a paper debunking the 50% derating number. The first example they use is actually about the peak surge current which they tie to the voltage rating. There they show the 50% rule is not adequate, but since the real issue is surge current, the 50% rule is of no value anyway. The second example uses a tantalum cap on the output of a current limited startup voltage regulator. Here they show the 50% rule is bogus and that 20% would be adequate, again because of the surge rating being tied to the voltage rating, not actually because of the voltage! The second reference 67 contains the typical 50% derating without justifying it except to say, "It is important to follow these guidelines as a protection measure against unexpected current surges and overvoltage conditions, which occur frequently in automotive circuits." So if this rule of thumb only applies in automotive circuits where overvoltage surges are prevalent, then why is it listed as a general rule? Why is this wiki page perpetuating this rule of thumb when the cited references don't actually support it?

Further, I found no support in either reference for the 3 Ω/V rule. Where is the reference for this? Clearly this is surge current related and if a series resistor is required, it should be calculated from the specifics of the application, not from a rule of thumb. Gnuarm (talk) 04:11, 11 January 2019 (UTC)Reply

Not a textbook edit

Way too much redundant detail - we have an article on "electrolytic capacitors", do we need to redevelop all the physics here as well? This isn't a textbook on capacitor manufacture. --Wtshymanski (talk) 00:09, 18 November 2017 (UTC)Reply

100% agree. — tooki (talk) 12:38, 12 October 2021 (UTC)Reply

MnO2 self healing mechanism image edit

I commented directly on the image file. However, I wanted to make sure this was seen and hopefully someone can fix it. Image: 1) correction to the spelling of crystallization and 2) "Oxidizing" should be "Reduction". This is correctly stated in the image subtext. 162.18.172.11 (talk) 18:36, 3 November 2022 (UTC)Reply