I have a SE clock signal (Sine-wave, 50 ohm) that I want to feed into the LTC6957-x, but the circuit requires a failsafe. In other words, when the input clock is disconnected, it can't oscillate, even internally. This is a low noise application any free-running oscillations is a concern. One option that I considered is to disable it with the SDx pins. But its not clear the SDx disable the first amplification stage. Is there a bias circuit I can use on the front end to avoid oscillations and not degrade the phase noise performance?