Hi, I have been reading the posts on high side MOSFET drivers, and still have some questions. I just want to drive 12V, 40amps, using a PWM signal. I drive 12V, the other end of the load is connected to ground.
- Would you use an N-channel mosfet because they are cheaper, better, etc. If I do, I would need a high side driver and a charge pump to generate at least 18 volts. I was looking at the IR2117 to drive it but its current (+200mA/-420mA) seems low to drive a P75NF75 mosfet. I ran some calcualations for a gate driver and it came up around 6 amps. I thought MOSFET drivers needed to drive higher currents because of the gate capacitance. Are there any high side drivers with the charge pump built in?
- If I use a P-channel MOSFET, I would still need a high side driver, what would you recommend? I have seen examples just using a 2N2222. Again, isn't that current low (500ma). If I use a series resistor to drive the gate, won't that slow it down even more?