Buckboost - Am I on the right track here?

Discussion in 'The Projects Forum' started by HellTriX, May 23, 2008.

  1. HellTriX

    Thread Starter Active Member

    Apr 11, 2008
    I'm experimenting with a discrete buckboost gate driver and was
    wondering if I'm on the right track here.

    I'm not sure if this circuit even addresses the current sink after the boost
    but in general is the bucking part to boost voltage above v-rail correct?

    I got my mosfets hot the other day when switching them on the high side forgetting about the need for a higher gate drive voltage. Designing my own
    buck boost would be a temporary solution until I get a proper gate driver IC,
    but this is mainly to be used as a personal learning experience.

    If I end up expanding this circuit to source and sink with a decent peak current
    and fast switching time as well as a low side circuit with proper delays I'd just
    assume use this instead of buy driver ICs. This is all besides the point. Am I on the right track? tnx

  2. Papabravo


    Feb 24, 2006
    I'm not sure that your circuit will operate the way you think it will. When the transistor turns on won't the other side of the cap try to go negative, but it cant because it is at ground?
  3. mrmeval

    AAC Fanatic!

    Jun 30, 2006
  4. Caveman

    Senior Member

    Apr 15, 2008
    I'm not sure about what you are trying to do here, but first of all you should model your mosfet gate load as a capacitance, not a resistance. The value of the capacitance can be usually found on the datasheet explicitly.