Re: Sanyo OSCON Organic Semiconductor Capacitors
Sorry, wrong:
quote You are very incorrect in saying that the large capacitors are not filtering 100 Khz. The very reason that they must have low ESR at that frequency is that it is very necessary. quote
Check out page 17 of the VRM controller datasheet i linked.:
Under design Procedure,
The "bulk" capacitors provide "hold up" during transient loading. The low impedace, high frequency ceramic capacitors reduce steady state ripple and bypass the bulk capacitance when the output current changes very quickly.
True, the caps do "filter" the output in a way, but not in the way you say.
The low ESR of the bulk caps is to reduce heating in them while they're at work, not for bypassing the 100kHz + switching noise. That's what the ceramic caps do. The lower the ESR, the less the cap will heat up, given a certain amount of current.
I'm not saying here that the Sanyo Oscon's are the best deal for your money. But i'm saying they're about the best cap you can put on a motherboard's switching VRM. They can supply more current than most other caps, provided you keep the temps down. If i was overclocking a liquid nitrogen cooled Pentium 4 Prescott at say 4.5Ghz or higher, i would certainly want Oscon's in my VRM, since such a Prescott would be extremely demanding on a VRM, and any voltage droop would be a bad thing..
Kc8adu:
Were the failed Oscon's Sanyo, or do other people make Oscon's also?? I thought that only Sanyo made the ones with the Oscon brand name.
Sorry, wrong:
quote You are very incorrect in saying that the large capacitors are not filtering 100 Khz. The very reason that they must have low ESR at that frequency is that it is very necessary. quote
Check out page 17 of the VRM controller datasheet i linked.:
Under design Procedure,
The "bulk" capacitors provide "hold up" during transient loading. The low impedace, high frequency ceramic capacitors reduce steady state ripple and bypass the bulk capacitance when the output current changes very quickly.
True, the caps do "filter" the output in a way, but not in the way you say.
The low ESR of the bulk caps is to reduce heating in them while they're at work, not for bypassing the 100kHz + switching noise. That's what the ceramic caps do. The lower the ESR, the less the cap will heat up, given a certain amount of current.
I'm not saying here that the Sanyo Oscon's are the best deal for your money. But i'm saying they're about the best cap you can put on a motherboard's switching VRM. They can supply more current than most other caps, provided you keep the temps down. If i was overclocking a liquid nitrogen cooled Pentium 4 Prescott at say 4.5Ghz or higher, i would certainly want Oscon's in my VRM, since such a Prescott would be extremely demanding on a VRM, and any voltage droop would be a bad thing..
Kc8adu:
Were the failed Oscon's Sanyo, or do other people make Oscon's also?? I thought that only Sanyo made the ones with the Oscon brand name.
Comment