I try to design a (relatively) low cost H-Bridge on N channel MOSFETs. I need to drive 8.5A peltier device with 12V and (roughly) 20kHz PWM.
(after reading some of the comments I changed this question to use P-MOSFETS for high side)
I plan to drive only low side MOSFETs with PWM, so I don't care too much about capacitance of high side MOSFETs. I was able to find quite cheap P-MOS transistors with an Rds value of about 0.02-0.06R.
My circuit would look like this:
I could probably use bipolar transistors for driving high side MOSFETs, but I have some spare N channel, I hope that using MOSFETs there is fine too.
Now the question is:
- Is it a good circuit design?
- What resistance values I should use for driving high side?