I am wanting to use the A and B outputs of a UC3871 or UC3872 chip to drive a push pull section and I want to use the C output to drive the PWM Buck section that feeds the push pull. The chip is only good for 24V and I want to take it up to about 35 V. My problem is how to drive the PMOS device in the PWM section. separate drivers I find use some sort of boot strap method and that won't allow me to go to 100% conduction on the PWM. Does anyone have any ideas on how to interface the PMOS device to the C output of the UC3871 or UC3872? Or is there a way I can invert the C output and drive an NMOS device and still get 100% duty cycle on the PWM?
Thanks - John