• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 46 subscribers
  • Views 203 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Why ADS5474 Data Noise Floor Not Flat

Tuan To
Prodigy 210 points
Other Parts Discussed in Thread: ADS5474

ADS5474 on my board is clocked at 400MHz. When I analyzed the data from ADS5474 using FFT, I noticed that the noise floor is not flat. The noise floor is sloped down from DC to 200MHz. The noise floor at the DC end is higher than the 200MHz end for about 5dB. Why the noise floor is not flat? What makes the noise floor sloped down?

Thanks, Tuan To.

  • 0
    TI__Mastermind 29220 points

    Hi,

    I do not see a noise floor that is not flat.  I am attaching an FFT plot from the testing of one of our EVMs from the last build of EVMs.   I would need to see your plot, and perhaps if you captured a file of samples you could import that into the HSDCPro GUI that we used with our TSW1400 capture card and see what the noise floor looks like there too.

    Regards,

    Richard P.