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trodas
03-02-2006, 07:24 AM
To futher clean up the RMS ripple of any spikes (usually hi-frequency ones) is used on all mobos ceramic caps with relatively little capacitance, yet that is exactly why they filter the spikes out well. Sometimes it is not just about the spikes, sometimes there are a bit higher capacity, like the ceramic caps into DFI LP B/Ultra InfÃ:banana:nity CPU socket (into and bellow) are 5,3uF ones (at least what I measured on the one I soldered off and on again), while in general is wise to bridge the big caps on mobo with about 47nF ones.

Now what do I ask about?
Simple thing.
Recommended manufacturer for hi-quality ceramic caps.

I already got a few types of very good electrolyte caps, like Samxon GA, Nichicon HZ, Rubycon MCZ,Chemi-con KZJ, Samxon GC, Nichicon HN or Panasonic FM ones, but I'm clueless about the ceramic ones.

Anyone can give me a hint, when looking for the best quality (lowest ESR, ESR)? Thanks ;)

trodas
03-02-2006, 08:39 AM
For the filtering - ATM I come up with this:

- Panasonic 10uF 16V ECG X5R -55°C to +85°C size 1210 (3.2 x 2.5 x 0.85/2.0/2.5)
ECJ-4YB1C106K

- Panasonic 5.6uF 6.3V ECG X5R -55°C to +85°C size 1206 (3.2 x 1.6 x 0.85/1.15/1.6)
ECJ-3YB0J565K

- Panasonic 100nF 16V ECG X7R -55°C to +125°C size 1206 (3.2 x 1.6 x 0.85/1.15/1.6)
ECJ-3VB1C104K

10uF caps in ceramic pack great ESR/ESL values and there are a lot's of them missing on the mobo.

5.6uF is the size of caps missing bellow the CPU socket and probably the ones that should be inside the CPU socket as all. Total - 8 missing ones.

100nF is the one I picked up to do the filtering. The 47nF capacity aren't big enought - only 2mm long, this won't be possible to solder between the legs of every bigger cap found on this board.

What do you think, acceptable? :confused:

Specs:
http://www.panasonic.com/industrial.../ABJ0000CE4.pdf