Synchronization between different EPWM modules of TMS28032

Yi zhang

Other Parts Discussed in Thread: CONTROLSUITE

I need to use EPWM4 and EPWM5 to control switches in one buck or boost circuit, so I want to synchronize these two modules. What I plan to do is set EPWM4 as master(generate sync out at CTR=ZERO)and EPWM5 as slave(receive sync in from EPWM4). But I wonder if EPWM4 can serve as master or only EPWM1 can be set as master.

over 9 years ago

0 Brett Larimore over 9 years ago

TI__Guru 57255 points

Hi,

Any upstream ePWM can be a master for a downstream PWM.

The PWM_1ch_Cnf.c file within controlSUITE's digital power library, may be helpful:
\controlSUITE\libs\app_libs\digital_power\f2803x_v3.5\CNF\

The other useful resource is the Synchronization scheme portions of the ePWM User's Guide:
http://www.ti.com/product/TMS320F28035/technicaldocuments#doctype6

Thank you,
Brett

0 Yi zhang over 9 years ago in reply to Brett Larimore

Intellectual 830 points

Hi Brett,

Thanks a lot for your quick answer. Then I suppose all epwm modules are initially synchronized without any phaseshift, even if we do no additional settings. That is what I observed on oscilloscope. Is that right?

0 Brett Larimore over 9 years ago in reply to Yi zhang

TI__Guru 57255 points

Hi,

If you make TBCLKSYNC = 0, configure your ePWM settings, and then TBCLKSYNC = 1 (as recommended in our documentation), then all PWM timers will start aligned.

As a result, the ePWM modules will be synchronized, however not by the synchronization chains.

In the various peripheral user guides, you can find what the reset value of each register bit is.

Thank you,
Brett

0 Yi zhang over 9 years ago in reply to Brett Larimore

Intellectual 830 points

Got it. So it is the reset value that matters. Thanks.

C2000™︎ microcontrollers

C2000 microcontrollers forum

Synchronization between different EPWM modules of TMS28032