I have an OCXO oscillator (5Vpp, 38.4MHz sine wave, 5ppb) that needs to be fed into an IC that has max input level of 800mVpp. I am trying to use a set of schottky diodes (1N6263w) to clipped sine wave. It seems that I have inevitably introduced instability to the OCXO output. Is clipping diodes the right strategy to do this or is there other circuits that I can use?

 

Have you tried voltage divider?

 

Have you tried voltage divider?

Thanks for the reply! My concern with voltage divider is that it changes the slew rate of the OCXO signal. Hence, going down the path of the clipping diodes to try to preserve the slew rate.

 

I am trying to use a set of schottky diodes (1N6263w) to clipped sine wave. It seems that I have inevitably introduced instability to the OCXO output.

Do you have a resistor between the oscillator output and the diodes?
If not, you need one.

 

Thanks for the reply! My concern with voltage divider is that it changes the slew rate of the OCXO signal. Hence, going down the path of the clipping diodes to try to preserve the slew rate.

What is there about the rest of the circuit that makes that a problem? In fact, what is there about the rest of the circuit? I assume it has electronic components. Do you have the part numbers?

ak

 

I have an OCXO oscillator (5Vpp, 38.4MHz sine wave, 5ppb) that needs to be fed into an IC that has max input level of 800mVpp. I am trying to use a set of schottky diodes (1N6263w) to clipped sine wave. It seems that I have inevitably introduced instability to the OCXO output. Is clipping diodes the right strategy to do this or is there other circuits that I can use?

Shottky barriers diodes tend to have higher junction capacitance than regular silicon, and some outputs don't like capacitive loads.

I would suggest a resistor between the output and diodes - but I'm thinking there should already be one.