Good Day
We are using the LMH1980 in a sync interface unit design and notice that with no sync input random output pulses are at times output from the device. With a normal PAL input the device works as expected. We have found a solution appears to be to connect a 1 M Ohm resistor from the input pin 4 to Ground.
We have checked that the Rext off pin 1 is within 1% tolerance specified.
Our input LMH1980 design was copied from the reference design.
Please could you advise either the likely cause of the problem or confirm that our solution is acceptable (no adverse knock on effects on sync pulse timing).
Thank you
David