Hi Simon,

using a variable cap is a very bad solution. Its many times easier to correct the deviation by software.
Then the adjustment can easy be made by the customer. The only task, he must run the clock 1 month or so and adjust it again. Then the software get the difference, calculate the correction value and store it in an EEPROM cell.

See also at:

http://www.specs.de/~danni/ap...curacy.htm


Hi Yeff,

I use always 33pF (4MHz ... 24MHz) without any problems.


Peter