AnsweredAssumed Answered

Differences in Signal Quality on AD9958

Question asked by Chrispy on Jun 9, 2017
Latest reply on Jun 13, 2017 by Chrispy

Hello,

 

after i first struggled to receive Signals out of my AD9958 i'm able to control it. I'm able to receive the desired Frequencies. 
The problem is, that i have differences in the Signal Quality of Channel 1 and 2 and i'm not sure where there could be the problem. In the attached image you could the the Two Signals. I want to create on Channel 1 a Signal with 3.80005 MHz and on Channel 2 i want to generate a signal with 4 times the Frequency of Channel 1. 
I need the Channel 2 as Reference Signal for an IQ-Demodulator (AD8333).
Because of the Jitter in the Signal the IQ Demodulation doesn't works properly. When i use an external Frequency Generator only for the Reference and the Signal of Channel 1, the IQ works fine. That is not the case when using Channel 2 as Reference.
First i thought that i have to use the Filter mentioned in the Evaluation Datasheet so i connected this precious Filter to the output but without any succes.  
So im wondering if the Chip has a defect or if there is something else i could try to remove the jitter from the Signal.
Thanks for you help and i also want to thank you for the great support i got on the last posts.

Kind regards 

Attachments

Outcomes