> If minimising the PPS jitter, is important adding a single D flipflop to > resynchronise the output PPS signal to the 5MHz input will be worthwhile. > A relatively complex chip like a PIC is likely to produce a PPS output > signal with a jitter much greater than that produced by a single flipflop.
Bruce, double check the PIC data sheet and see if this is really true. They are not complex chips; they run DC to 10 MHz, and all outputs are synchronous with the clock. > Measuring the PPS output jitter of the PIC will be somewhat challenging > as It I would expect it to be somewhat less than 100ps. I think way less. I measured it with a 5370B when I designed the divider ten years ago. But I'll measure it again for you using better equipment. > The corresponding output jitter at the resynchronising flipflop output > should be significantly less than 10ps even for a 74HC74. > In this case only the flipflop's random jitter is significant as the > frequency and duty cycle of the PPS input to the flipflop are constant > apart from the effects of jitter. > > Bruce This would be an interesting experiment. /tvb _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.