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.

TMS320F28386S: HRPWM Jump When Coarse Count changes

Part Number: TMS320F28386S


Hi...

Am using TMS320f28386S for generating unipolar PWM in our product. Am switching at 75000 Hz and hence my PWM CMPA resolution is poor. I have switched to HRPWM now. But i am facing an issue with HRPWM. As per my understanding, the MEP_ScaleFactor for this processor is about 37 @ 200Mhz Sys Clock. Based on which i am using the formula given in the TRM to provide the coarse CMPA value and the fine HRCMPA value. 

It seems like the Hi Res Counts are effecting in the output but when the Coarse count changes, there seems to be a jump. the change is not continuous. What am i doing wrong. 

I am using the coarse counts as per the usual duty formula. Then i am taking the fractional part and doing as attached...

Appreciate your help. thanks

Santhosh