02.01.2006, 09:49 AM
I want to design overcurrent protection in my full-brigde, but where to put this and how to make it fast enough? Will a 5-10 mOhm sense resistor on low side of each half-bridge leg affect performance worse than if it is placed on the high side? Second, it is difficult to construct a high side sense circuit that is fast enough to react on individual switch pulses (thinking about using MAX4080 with BW 250kHz), how to overcome this? I suspect that the FETs will die during a short if I have large banks of low-esr caps and sense the current going into the capacitor banks in order to get a slower process to measure.
Edit: here is a suggestion using ordinary op-amp and fets, could this be fast enough and noise immune enough to work?
Edit: here is a suggestion using ordinary op-amp and fets, could this be fast enough and noise immune enough to work?