What period do I use to get 12.5 kHz PWM carrier freq on F28069?

Altair Forum User
Altair Forum User
Altair Employee
edited October 2020 in Community Q&A

Submitted by Joe on Thu, 04/05/2012 - 21:27 

 

Can you tell me what ePWM settings to use with the 28069 epwm to get a carrier frequency of 12.5khz?

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited June 2016

    Submitted by Anders89 on Thu, 04/05/2012 - 21:35.

    The PWM period is found by dividing the system frequency (80 MHz for F28069) by the desired PWM carrier frequency (12.5 kHz or .0125 MHz in your case). This gives a period of 6400. However, if you use the Up/Down PWM Counter Mode, then the effective period is double the counter period so you must divide the period by 2 to get your desired carrier frequency. So the answer is use a period of 6400 for 'Up' or 'Down' Count Mode and 3200 for 'Up/Down' Count Mode.