Hal, Yes, there are negative delays. The goal is that the physical 1PPS output is, on average, exactly on-time. If designed right, that means as many negative offset pulses occur as positive offset pulses. The spread gives you the RMS value.
This is exactly what you want for a GPS timing receiver. /tvb (i5s) > On May 18, 2014, at 1:42 PM, Hal Murray <[email protected]> wrote: > > > The ref output is the minimal delay through the chip covering the input and > output pad buffers. It will vary slightly with temperature and voltage. > > There are no negative delays in that sort of chip. It's just a bunch of > gates/buffers with a carefully calibrated delay. (For a negative delay, you > would need something like a PLL.) > > If the delay from the M12+T might be negative, set the antenna cable delay to > be a bit short and add on a constant in software. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
