As in below picture, I'd like to control no output during in 'A' period between each linear ramp down sweep.
What is the most convenient or fast control method to make no output ?
I'm designing with AD9959.
Two approaches jump to mind, there may be others:
1) Set the amplitude scale factor to 0. The DDS engine will still be running, so if you care about the value in the phase accumulator when you start the sweep, this may not be your best answer, but I think it will be pretty straightforward to implement. You could also use the clear phase accumulator bit to reset the phase accumulator to 0 degrees before you start your next sweep if the unknown phase was an issue. Because you have the accumulator going and switching occurring, this will likely consume a little more power than option 2
2) Set the FTW to 0 at the end of the sweep. This will retain the phase left over at the end of each sweep in the phase accumulator, it may not be quite as clean to implement as the ASF=0 because you switch from a ramp to a static FTW and back, but it will accomplish the goal.
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