Ceramic capacitors and working voltage

[gbono]

It's not an audio/MI related article but I find many folks are not aware of this issue.

Temp and voltage variation of ceramic caps, or why your 4.7-uF part becomes 0.33 uF | EDN

[Tom Phillips]

Good information to bring up.
It also turns out that this has been mentioned on MEF in the past. At least one example is in post #30 of the discussion at http://music-electronics-forum.com/t31143/ but it was burred and mostly forgotten in one of the many discussions about the "sound of capacitors." Science trumps internet lore.

[Richard]

Didn't have time to digest it but that sounds interesting. Does this mean that my cathode bypass caps could effectively be much smaller than what the schematic reads?

[Jazz P Bass]

Didn't have time to digest it but that sounds interesting. Does this mean that my cathode bypass caps could effectively be much smaller than what the schematic reads?

That article was concerned with "ceramic" capacitors.

Your cathode bypass capacitors are electrolytic.

Rant: why the author used a ceramic cap in a timing circuit is eluding me.

[tedmich]

C0G or NP0 are the way to go, ceramic wise. Can't get big values though, and its more expensive than dirt (ie X7/X5)

[J M Fahey]

Rant: why the author used a ceramic cap in a timing circuit is eluding me.

And how did they:
* make a *ceramic* 4.7uF cap
* and pack that inside an SMT package

makes me think that the ceramic layer was *atoms* thick .

When you go that far from established, don't be surprised that things start to crumble.

In my book, POOR engineering.
Just sayin'