[En-Nut-Discussion] Ethernut 1.3H Crystal 32.768khz

[Harald Kipp]

Hi Ayman,

On 08.04.2013 22:29, Ayman Hendawy wrote:
> Thanks for your detailed answer, actually I was asking for a part no. for
> this crystal, regarding the two part numbers, they mentioned that the
> capacitor is 12.5pF, how can I use these crystals without using the
> mentioned capacitors, by another meaning if I replaced Y2 by these ones
> will work, How?

You cannot look just to the crystal only. You need to check the
oscillator first.

http://www.atmel.com/images/doc8333.pdf

The 32kHz oscillator on the AVR die has internal capacitive loads.
Therefore, external capacitors are not required, typically.

On Ethernut 1.3H an Epson Toyocom Q.032768MC146A crystal is mounted.

Regards,

Harald