On Mon, 8 Jan 2018 13:14:16 +0000 Chris Wilson <ch...@chriswilson.tv> wrote:
> Thanks for the very fast reply! Would it be possible to use one of > these frequency multiplier IC's? Sounds simpler, but maybe there are > down sides? > > http://uk.farnell.com/on-semiconductor/nb3n502dg/pll-clock-multiplier-8soic/dp/2101849 Bruce's idea is much lower noise. The NB3N502 datasheet states an typical output jitter of 15ps. That's HUGE for a normal VCXO output that is usually below 1ps. The low-noise OCXOs have something in the order of 100fs. Alternatively, you can use something like an ADF4002 and an VCXO with 25/27MHz. That should give you a much better performance, mostly limited by the VCXO. But you will need to have a sine-to-square conversion of the 10MHz output of the Thunderbolt first, as the ADF4002 has a slew-rate limit on its reference input. BTW: stay away from any VCXO that mentiones "programable" in its datasheet. These are XO + fractional PLL combinations where the PLL allows quick and cheap realization of odd frequencies. But their spurs and noise floor is much worse than normal XOs. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson _______________________________________________ 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.