Unknown Chang caps; suitable substitute?

[hackdog]

I'm about to recap a portable DVD player motherboard which doesn't power on anymore. Some of the caps are slightly bulged, there is no output on the buck converters, no indication of any other damage, so it looks like the usual bad electrolytic scenario. The problem is that I can't tell the specs of the original caps. They are Chang 300uF 16V 105 deg C, 8mm diameter x 8 mm high, but without any series marking on them.

Suitable replacements I can obtain include SunCon (Sanyo) WG and CA series. The WG are "Super Low ESR" (30 mOhm at 100kHz, 1140 mA ripple current), the CA are "Low Impedance" (160 mOhm at 100 kHz, 410 mA ripple current).

Which should I pick? The WG series looks nice but I'm not sure if the low ESR may have any negative consequences for stability etc. given that I don't know the circuit design or the rating of the originals. So the CA might be a safer choice, given all the unknowns. What do you think?

[stj]

Re: Unknown Chang caps; suitable substitute?

if it's on a high freqency line like a buck or boost convertor, you MUST use low-esr.

[Behemot]

Re: Unknown Chang caps; suitable substitute?

They often use cheap GP crap in these things, so most likely even GP caps would be OK, low-ESR better. Ultra-low ESR are inteded for things like GPU, CPU VRM, not much of anything else.

[hackdog]

Re: Unknown Chang caps; suitable substitute?

Thanks for the feedback stj and Behemot. In the meantime I noticed that ELNA RJF is also an option: 72 mOhm at 100kHz, 760 mA ripple current. I think I'll go for those, as they are low ESR but not as extreme as the SunCon WG series. Seems like a reasonable choice for this application.

[Stomper]

Re: Unknown Chang caps; suitable substitute?

Anyone help so I can replace this capistor. It says mdc 3310% npo.

Someone sent me a 33j 1kv npo and said I could use it..