Hey I am also having trouble with the h bridge design I am trying to get a proof of concept to work and I can not get it to work in Pspice. I was wondering if anyone knows what I am doing wrong. I have been doing trouble shooting this for a long time and I seem to be burned out. All I want to do is use the p mosfets, and n mosfets with a LM393 inverter to drive the P mosfets. I am using V pulse just to simulate the different directions the load can take.

 

From the IRF540 Datasheet:

VGS(th) Gate Threshold Voltage VDS = VGS ID = 250 μA 2 3 4 V

4V difference is needed to barely turn on the MOSFET, you need to add MOSFET drivers (transistors, or a mosfet Driver IC) to get the gate voltage above 8V (Closer to Drain Voltage in this app, of 9.6V).

 

The power supplies are backwards on the LM393s.

Also, you are going to need to get the gate voltage of the P-channel MOSFETs a lot higher than 5V to turn them off. Try 9.6V instead.

 

Alright so I got my H bridge circuit figured out, all it took was some time to clear my head. The problem is that right now I am trying to produce amplification separately with the LM393. For some reason when I spice it it does not seem to want to work. The circuit is below, is there just some dumb error I am making to not get me the desired voltage?

 

Oke so I looked it up and I added a "pull up" resistor to the circuit between the output and the 9.6V and now the circuit only follow the voltage without amplification.