I'm implementing a buck boost converter. I need a variabe duty cycle with constant frequency of 200kHz(without using a ardino board in which I suppose I would have to upload a program everytime to get a new duty cycle ) to drive the igbt. I was thinking if using a opm comparator with one input as Vref with a potentiometer to get variable duty cycle and another input as a constant frequency sawtooth wave from microcontroller . But can i give such high frequency wave to opm in the first place n get a decent pwm signal? Isnt there another way ?