AnsweredAssumed Answered

PWM Duty Cycle

Question asked by Jayakrishnan S on Jan 21, 2016
Latest reply on Jan 29, 2016 by Jayakrishnan S

Hello

 

I am using PWM Module in MC56F8037 Microcontroller to generate PWM Signals for MOSFET Control application in my

project. When Iam using the Complementary PWM Setting, the PWM Signal Duty Cycles are getting reduced with increase

in frequency of PWM Module Setting. The Dead Time and Signal Shape is Ok.

eg, a 1KHz PWM and 60% Duty Cycle Setting for first PWM pin generates 60% and 40% Complementary PWM Signals for

1st and 2nd Pins with Correct Dead Time. But for Higher Frequencies like 10KHz, 100KHz, 200KHz etc the Duty Cycles get reduced to about 55-50%

and 35-30% Respectively. I have checked the code in codewarrior, i did not find any error.

 

is this the hardware problem or have I missed something while changing the Frequency of Operation of PWM Module?

My application requires PWM Signals at 100KHz-200KHz. Please send some suggestions.

 

Thanks

JK

Outcomes