Preferred caps for power supplies

[wkbdgeorge]

Hi,  I'm looking into replacing some caps that are in a power supply.  I was looking at specs such as leakage current and ripple current and it got me wondering what are the best specs for main caps that are in a power supply. 

For this particular project that I'm working on, I'm replacing some potentially old caps in the amplifier of a subwoofer. Thats my focus right now, but I'm still interested in other applications as well.

In the past, I've used Nichicon VZ series, but was looking at FG and KZ possibly for this project.  Any thoughts?

-George

 

[wkbdgeorge]

Also, Sidequestion......Do you want a cap's rating to be higher or lower on ripple current?  I just wasnt sure if the stated rating is for what it can handle, or what it puts out. 

Thanks!
-George

 

[JohnRoberts]

Most important specs are amount of capacitance in microfarads and rated voltage.

Ripple current is probably not an issue unless you are dealing with a switcher.

JR

 

[wkbdgeorge]

switcher as in switch mode power supply?

 

[QUEEF BAG]

yup

 

[GCalo]

Nichicon PW series are perfect for power supplies. Highly recommended

Available from Mauser and DigiKey

See the attached Nichicon listing.

 

[QUEEF BAG]

i have always noticed the high leakage spec
for the PW series...
i see them mostly in power supplies, where i guess their leakage
doesn't matter as much?  not to mention the availability of high voltage
values.

i don't see them in the audio path as much, is this because of leakage?

 

[GCalo]

PW are actually very good caps. Tolerances spec out at about 5% -7 % despite being sold as a 20% cap.

Look at spec sheet I attached for leakages. It's actually quite low.

I by-pass P/S caps with a .01 metallized polypropylene, and it yields very clean power.

For higher end audio electrolytics I use the ES series.

For slightly lower grade audio lytics I use FG series

 

[BradAvenson]

If you are looking at Nichicon also check out the HE line. 
http://products.nichicon.co.jp/en/pdf/XJA043/e-he.pdf

Long life, high temp, low impedance.  Seem nice.

 

[GCalo]

That series looks good as well and goes up to 18,000 mfd.

I can't see what the preferred application is so I'll assume standard polarized applications.

 

[QUEEF BAG]

didn't see spec sheet...

united chemicon has some good lookin' caps too.

all those radials are good, but

- what i really need is a good axial cap for filtering in modules.
like 1200 or 1500 uf  both 50 volt and 63 volt.  prefer 105 degree.

those nice blue BC 138 caps are pretty good, but freakin' expensive.
and i think slightly over rated.

nichicon TVX are good, but only 85 degrees.

united chemicon used to have one, but i can't find anyone with it now.

 

[GCalo]

The PW series comes in 105 deg!

 

[BradAvenson]

- what i really need is a good axial cap for filtering in modules.
like 1200 or 1500 uf  both 50 volt and 63 volt.  prefer 105 degree.

I think you might consider laying a radial on its side.  I have found that is what most of the small switch mode power bricks do. 
For a new design this is no problem, but as a repair it gets slightly more sketchy from a mechanical point of view.  A little dab of RTV can help.