[time-nuts] GC-1000 Clock Cap Choice?
lists at rtty.us
Sun Jan 16 22:59:03 UTC 2011
The other thing to watch out for is the temperature coefficient. Some of the high K materials move a *lot* with modest changes in temperature. There are indeed industry standards on what a given dielectric code should be. In some cases there have ben liberties taken interpreting the codes. You really need to go back to the original data sheet on each part to see what the temp co actually is.
In a modestly warm box (say 60 C) the net effect between voltage and temperature may be that you have < 1/4 your original capacitance.
On Jan 16, 2011, at 5:15 PM, Poul-Henning Kamp wrote:
> In message <4D336A19.40709 at freenet.de>, "Dr. Frank Stellmach" writes:
>> High cap value Ceramics are available since years, [...]
> Can you clarify one thing for me: When I studied datasheets for these
> it looked like they drop 50% of their capacitance at a DC voltage
> of 10-20V.
> Doesn't that make them a so-so bargain for power supply bulk capacitance ?
> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
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