AnsweredAssumed Answered

AD9833 failure/No output

Question asked by AVR on Sep 16, 2013
Latest reply on Sep 29, 2013 by AVR



  We have used AD9833( MSOP) DDS to generate sine waves in our circuit we have two identical DDS sections controlled through I2C communication from a microcontroller  , We could get sine waves as per our requirement  from 2khz to 4khz range and are satisfactory.

Now we are finding some failure in AD9833 devices in our circuit,


1) failures are observed after few days or some times after few weeks, most of the time both DDS are not working.


2) In failed boards, when we replace DDS it starts working


3) in failed boards other components such as microcontroller ,DAC,display driver  etc are  working very well.


4) Please find my schematic attached and let me know whether my AVDD and DVDD supply is ok or need any modification?


5) Also in the schematic Vout pin of DDS is connected to a voltage divider network, is that ok or will it affect the performance?


Could you please tell me how to identify the root cause of this failure?


Thanks in advance,