• TI Thinks Resolved

ADS5296A: after init, sometimes ads5296 get digital noise. test pattern is ok

Prodigy 90 points

Replies: 13

Views: 274

Part Number: ADS5296A

after init: some fix chan has digital noise: the analog input is zero, but the adc output has some bit has err '1'.

power on the system 6 times, get 1 err init result probably。

the top channel is ok, but the below channel has some err. the analog input is same. when i switch to the test sync pattern or deskew pattern, the result is ok,

like the picture below.

below is my design:

  • In reply to Xiaochen (Sean)Xu:

    I only find one board like this, other boards don't have this problem. so I think the hardware around the adc affect the adc, when I init the adc and sample the analog signal.

    I will have ten boards with smt, after some days, I  will check the problem then.

  • In reply to Xiaochen (Sean)Xu:

    I may try that diode.

    After some days, we will have some more boards, I will statistic then.

  • In reply to jie zhu60:

    Jie, 

    Thanks!

    we will wait for your results from more boards.  you can also leave your email and we can have more specific discussion off line. Thanks!