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Message ID: 946     Entry time: Tue Jul 7 05:13:03 2026
Author: Jonathan Bradshaw 
Subject: REFCLK input characteristics 

Hello all

We are developing our own product with a DRS4 inside, and I'd like to get some more information about the REFCLK input.  Is there any information available about:

  • What's the input capacitance?
  • What range of input common mode voltage (VCM) is recommended?  I've been using 0.9V, but I realise that's a bit lower than the typical LVDS 1.2V.  It seems to work, but might that be degrading performance, or risking reliability problems?
  • What are the differential mode input high and low thresholds?

Thanks all

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