[time-nuts] Zero-Crossing Detector Design?

[Chris Hoffman]

Can anyone suggest a good reference design for a zero-crossing detector? I am trying to home an ADC sampler trigger to the 1VRMS (50ohm) 10MHz sin from my XL-DC... And now I'm thinking that I should just home the uC clock to it, as well.

Essentially, I believe that I'm looking for an efficient, stable, and accurate sine-to-square converter... and I'll welcome any advice in this area. 

This may also be used in a 1KHz 5Vpp IRIG-B decoder... I don't feel like rectifying the signal, to be honest. I want to try to keep a smaller BOM, sense the waveform primarily, and crunch numbers inside the uC. 


-CH

Chris Hoffman
cq.kg6o at gmail.com
http://ar.ctur.us