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Sweep Priority Complete a full sine wave or sweep time

Question asked by jcanyon on Apr 20, 2018
Latest reply on May 29, 2018 by KennyG

Hello.  

 

I have the AD9914 EVK operating in swept frequency mode.  In this mode, you offer frequency step AND Sweep duration.  I am writing to determine the chip algorithm / priority.

 

Given the example Fstart =400MHz  Fstop=450MHz  Fstep=10MHz  Sawtooth mode Sweep time =24.6e-9 Sec.

 

This example (Used to make a point, not implimentable) sweeps 11 frequencies.  Will the dwell time be 24.6e-9  / 11 or will the dwell time vary so the DDS completes a complete sine wave then moves to the next - noting 1/400MHz takes more time than 1/450MHz.

 

This example is detailed below.  Note in order to complete one full cycle of each of the 11 steps below it takes 24.6e-9 seconds.

 

Thanks!  Jim

 

StepFreqDuration of one cycle
14.00E+082.50E-09
24.10E+082.44E-09
34.20E+082.38E-09
44.30E+082.33E-09
54.40E+082.27E-09
64.50E+082.22E-09
74.60E+082.17E-09
84.70E+082.13E-09
94.80E+082.08E-09
104.90E+082.04E-09
115.00E+082.00E-09

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