Messages in this thread | | | Date | 10 Jun 2015 12:27:38 -0400 | From | "George Spelvin" <> | Subject | Re: Discussion: quick_pit_calibrate is slow |
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Arjan van de Ven <arjanvandeven@gmail.com> wrote: > btw one thing to think about; if you calibrate VERY quickly, you need > to consider spread spectrum clocking.
Excellent point! But spread spectrum clock modulation rates are typically about 30 kHz, so 1 ms will average over 30 cycles, which should be enough.
The faster the modulation rate, the more the EMI peak is flattened. But too fast produces unaceptable cycle-to-cycle timing variations, also known as clock jitter.
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