H bridge Design with p mosfet

barry said:

Not sure what those source resistors are "47E". 47K? 47 ohm? Not sure why you need them at all. And are those 22K on the gates of the PMOSFETS? Why so high? The circuit looks basically correct, but I would verify several things:
1) Is it wired properly?
2) Is there enough gate drive to turn those mosfets on hard enough to handle the load? Nominally, they should see about 10V Vgs, you've only got 5V on the N-mos, and, I don't know WHAT the gate voltage on the P-MOS is (depending on what that 47E is). You'll note that everything for those FETS is speced at Vgs=10V.
3) You might want to look at using logic-level MOSFETS.
4) What's your load?

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cl10greg said:

What is the system doing?

Some notes:
When your N transistor drives the PMOS low it is just creating a voltage diver that ends up keeping the gate voltage on the PMOS at 8.17V. Depending on the PMOS this may keep it always off no matter how you switch it. You shouldn't need that 47K resistor anyways.
All the NMOS transistors don't have current limiting resistors for their gates. Depending on your 5V driving signal, it could damage the driving components from high current spikes.
I would add flyback diodes to mitigate the motor EMF.
Check the body diodes of the PMOS to make sure the orientation is correct in relation to the motor

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