Author Topic: Question about these two caps  (Read 602 times)

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Offline jayjr1105Topic starter

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Question about these two caps
« on: July 03, 2020, 11:35:26 pm »
I have a PSone that needs these two caps replaced to fix video issues.  It's very common on this board.  I ordered replacement SMD aluminum caps 220uf 6.3v and I already removed the old ones.  They are reading normal around 220uf but ESR is well over 3 ohms.  Is this why they are bad? Original's are 220uf 4v btw.

« Last Edit: July 03, 2020, 11:37:22 pm by jayjr1105 »
 

Offline helius

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Re: Question about these two caps
« Reply #1 on: July 04, 2020, 12:08:37 am »
At what test frequency was the ESR measured 3 ohms?
I'm not familiar with that circuit, but as a guess, I'd say that they are coupling the output signal. High ESR in a coupling capacitor can lead to weak signal drive. Other problems could be (electrical) leakage, which would cause DC offset on the signal.
« Last Edit: July 04, 2020, 12:10:24 am by helius »
 

Offline Bud

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Re: Question about these two caps
« Reply #2 on: July 04, 2020, 02:16:55 am »
These SMD low profile electrolytic caps have high ESR in my experience, i mean higher than typical radial caps of same value, so 3 Ohm may be normal. 
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