Original question:
Hi expert,
My ctm want to do AC coupling input for LMK00304 . I see below post saying there is internal biasing providing the input offset -0.3V. And I just want to confirm this internal biasing provides the common mode voltage for the input (VCMD>0.25V) so external biasing is not needed? And work well both for LVDS and HCSL signals? Thanks.
Hi Zach,
Termination is still required but biasing is not needed if using option B since there is the internal biasing in the LMK00304 input buffer. This applies to HCSL as well.
I also checked with our LMK00304 IBIS model to confirm internal biasing with HCSL input. With VID measuring 800mV, VCM reads around 800mV, which is within the datasheet spec.
Regards,
Jennifer
