Author Topic: EDDP - ADC & PWM synchronization  (Read 83 times)

valahia

  • Active Member
  • *
  • Posts: 6
EDDP - ADC & PWM synchronization
« on: June 06, 2019, 10:50:01 PM »
I was wondering if the ADC sampling is synchronized with the PWM signal in order to avoid sampling, when the PWM is switching. I was looking through the code but could not find anything about  this.

Thanks for help,
Adi

Oleksandr Kiyenko

  • Global Moderator
  • Sr. Member
  • *****
  • Posts: 347
Re: EDDP - ADC & PWM synchronization
« Reply #1 on: June 07, 2019, 02:47:45 PM »
Hello Adi,

It's possible, but it's not a good solution as a project become more platform dependent. If you want to improve the project in this direction, maybe better to add a low-pass filter?

Best regards
Oleksandr Kiyenko

valahia

  • Active Member
  • *
  • Posts: 6
Re: EDDP - ADC & PWM synchronization
« Reply #2 on: June 07, 2019, 05:40:40 PM »
Oleksandr,

I really appreciate your response. Indeed a filter is useful for low power applications, but I don't think would have the same efficiency for higher power machines. Now, this idea with synchronizing the ADC & PWM, in order to avoid sampling during the switching, is very popular on the DSPs. Normally the PWM is generated by a up-down counter and the ADC would sample when counter = zero or when counter =  period or both.

Because I am looking to have a synchronization between PWM and ADC, and to be able to trigger the ADC sampling only at a specific times given by PWM, let me know if you have any suggestions, as at this moment I don't have a thorough understanding on how this application works.

Best regards,
Adi
 

Oleksandr Kiyenko

  • Global Moderator
  • Sr. Member
  • *****
  • Posts: 347
Re: EDDP - ADC & PWM synchronization
« Reply #3 on: June 11, 2019, 08:00:20 AM »
Hello Adi,

so you need to modify axis_AD7403 and axis_pwm cores to work together. This cores you can find in ip_lib folder in the platform project.

Best regards
Oleksandr Kiyenko

valahia

  • Active Member
  • *
  • Posts: 6
Re: EDDP - ADC & PWM synchronization
« Reply #4 on: June 12, 2019, 03:00:10 AM »
I guess that's the way to go Oleksandr!

Best regards,
Adi