TMS320F28075: TZ trip PWM output after one duty cycle finished

Young Hu

Part Number: TMS320F28075

Hi Champes,

My customer is designing digital power related projects using F28075. They have a question about TZ. What they want to know is that when TZ events happen, is it possible to trip the PWM output after one duty cycle passes, not immediately. For example, when overcurent event happened at time 1, TZ signnal is triggered. Then, PWM output will be cutted off at time 2.

They don't want to use software to trip the PWM output, because of the latency time.

Would you kindly suggest how to do this?

Many thanks,

BR,

Young

over 8 years ago

0 tlee over 8 years ago

TI__Guru 62975 points

Young,

This is not a typical scenario, but they might be able to configure the EPWM blanking window to ignore all but the first N cycles of each period.

-Tommy

0 Young Hu over 8 years ago in reply to tlee

TI__Expert 4185 points

Hi Tommy,
Do you think delayed trip zone function on F28075 can realize this requirement?
Thanks.
Young

0 tlee over 8 years ago in reply to Young Hu

TI__Guru 62975 points

Young,

If the EPWM is configured as shown (Count-Up and Count-Down), and the output is only expected to trip during one count direction, then yes, the delayed trip function should work.

The TZCTL registers will allow you to set actions for each count direction.

-Tommy

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28075: TZ trip PWM output after one duty cycle finished