Henk ten Pierick wrote: > Hi, > > An opto coupler seems good idea for an isolation amplifier but maybe > not for the phase noise. > Any experience? > > regards, > > henk > > _______________________________________________ > 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. > > Henk
The better optoisolators typically have a random jitter on the order of 50-100ps rms. This is considerably more than that for ACMOS logic (~1ps rms). Consequently the phase noise floor will be about 34 to 40dB higher than that when using ACMOS logic. Thus for low phase noise OCXOs using an optical isolator will significantly degrade the phase noise. An RF transformer is a lower phase noise solution to providing low frequency ground isolation. Achieving a reverse isolation of more than 140dB isnt too difficult with a few cascaded CB stages and a good layout combined with apprpriate shielding. Bruce _______________________________________________ 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.