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

TriX

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If you are trying to boost the VCC voltage above the rail (a boost circuit raises the voltage, a buck circuit lowers the voltage), then you will need to add an inductor in series with (or in place of) R2. You can not get voltage above the rail with the circuit shown (unless there's enough stray inductance in the collector circuit to give a small spike when Q1 turns off).