[time-nuts] ACAM GP22 Chip
not.again at btinternet.com
Wed Nov 25 20:54:30 EST 2015
>I wouldn't expect the noise to
>be in the ns range, but i wouldn't surprised if it was a few 10ps.
>I have never done any measurements though, and I don't think i've
>ever seen any jitter measurements for 32kHz oscillators, so take
>this value as rough guestimate.
On the GP21 board I used it was more like 10ns+. I don't know if
that's typical, but it wasn't a even particularly cheapo crystal as
the original one was faulty and I had to replace it. The official acam
board might be better, but the data sheet specifically talks about the
32K osc having a lot of jitter.
One of the problems of the data sheet is that it is really tailored
for those using it as a flow converter - some of the text does not
even make sense otherwise. That was one of the reasons I was planning
to test it more as a TDC, but just getting back to doing that now.
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