Converting Clipped Sinewave Output to CMOS

Written by on 3/18/2009

Clipped Sinewave output signal from many TCXO’s and other oscillators is easily converted to a CMOS output signal.

This simple circuit can be driven by the oscillators rated for 0.8V PP clipped sinewave output specified to have a maximum load of 10K ohm in parallel with 10pF. The output will have a CMOS square wave with a Vcc PP level and close to a 50% duty cycle.

This circuit will work from 1.65V to 5.5V and to over 70MHz at the lowest supply voltage.

The cost of converting clipped sinewave to CMOS is minimal.  For example, in March 2009, a nationally known electronics distributor listed a Fairchild logic gate at $0.052US ea in 5K quantities.  The Fairchild logic gate was available in both SOT23-5 and SC70-5 packages. The other components should total less than $0.01US.