Trip-Zone Malfunction - SimCoder F28335 3-phase PWM generator


I am having a hard time trying to make the PWM trip-zone work properly on PSIM 11.0.3. I am making a UPS project and for that I am using a F28335 DSC which I program using SimCoder.

In my board I have an error signal which I use to trigger the trip-zone of the F28335. In PSIM simulation, I have configure the 3-Phase PWM block to use this signal as trip-zone 1 / One shot, the trip action is selected to be High Impedance because I want to bring PWM signals low using 3.3k Ohm pulldown resistors connected to each PWM.

I have generated the code, compiled and run in the F28335 using CCS 8. However, when I bring the trip-zone 1 pin low (GPIO12), all the PWM pins go high, instead of high impedance. Actually, no matter which configuration I use for trip action, the PWM pins go high. I have checked the auto generated C code, and it seems that it is correctly configured (PS_SetPwm3ph1TzAct(eTZHighImpedance):wink: and well defined in the header file. I have also tried examples (Test 3-ph sine PWM with trip-zone (cycle-by-cycle).psimsch) and (Test 3-ph sine PWM with trip-zone (one-shot).psimsch) and the same thing happens when high impedance is selected.

The only reason I can think why it is not working is some malfunction in the pre-compiled libraries (PsBios…)

Please, help.

Hi Joel,

It looks like things are setup properly in the screenshot provided, we will need to investigate further. Can you contact our support team directly through the support form here:


Hello Albert,

Thanks for the idea. I have contacted them. The problem might be in my version of PSIM 11.0.3.