AD9786: Propagation delay

Document created by analog-archivist Employee on Feb 23, 2016
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What is the dependency of the propagation delay and settling time of the AD9786?


Propogation delay is dependent on mostly digital filter configuration since
each filter has its own group delay depending on #of taps (i.e. group delay=FIR
Taps/2) .  The 1st stage filter dominates since it has the most filter taps and
runs at the input data rate.  After the digital filter, the data will
experience around a 5 clock cycle delay (i.e. relative to DAC CLK) before
updating the TxDAC.

In terms of output settling time, the TxDAC core settles to 0.1% within 10
nsec. Note, since this device is used for frequency domain sort of applictions,
output settling time is not specified nor is an issue since a analog
bandlimiting filter follows the DAC which has even a greater settling time.