half bridge control using ucc 27201

i am trying to control a half bridge using ucc27201

i am succesful in contorlling the lower mosfet but i am unable to control the upper mosfet

i have connected a 0.1uf ceramic capacitance between HB and HS.

does the bootstrap function not ocuur properly due to this capacitor

do I need TO change capacitor if my operating PWM frequency is 32KHz

or is there some other problem

1 Reply

  • Did you have any luck solving this problem?

    I'm also having issues with the high side not driving properly. I also think it is due to the bootstrap not functioning properly.

    I'm driving IRFS3107 Mosfets.

    More info:

    Here's the schematic (note: the mosfets have been changed. I'm actually using the IRFS3107)

    The battery voltage is 28Vdc, the inputs to the mosfet driver are 0-5V dc signals from a microcontroller (not pwm).