How to use the comparator on AD9954?

The EVAL-AD9954 board outputs the Iout/IoutB to either the comparator inputs (filter) or the transformer/LC filters (J1, FILTERED_OUT_DUT1), not both at same time. If we want to use the comparator on AD9954 together with DDS clock (thru transformer and differential filter, then to differential amplifier) in our application, where does the inputs go? What is your suggestion? Thanks.

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    •  Analog Employees 
    on Jan 17, 2020 2:09 AM 9 months ago

    Hi wwqiao,

    What I can suggest, I hope I get your question right, is to use the filter first then cascade the output to the comparator. Since the comparator has high input impedance, you can tap a probe at the output of the LPF but before the comparator. So you have two outputs: the CW coming from the LPF, and a clock signal coming from the comparator.