problem in proteus simulation with H bridge

hi ihave some problem in proteus simulation with H bridge
can any one help me

Q2 and Q3 are reversed but you still need a proper driver for the upper mosfets, the gate voltage has to be higher than the mosfet power supply.
You need an isolated power supply or you can just use Pmosfets for the high side.

Alex

thank Alex for your reply
and it work now but what is the proper driver for upper mosfets
can i implement this circuit practically


best regard
alaalwi11

In order to use Nmosfet in the high part of the bridge (instead of Pmosfet that doesn't have that problem) you need a higher power supply voltage source for the gate or a bootstrap circuit to generate that higher voltage.
The problem is that you need a gate voltage that is higher than the source pin but as the mosfet turns on the source pin will have almost the same voltage as the drain (for example 5v) so your Vgs bias will be almost 0 (5v gate, 5v source).
This results is that the bias balances at about the gate threshold voltage where the mosfet has high resistance and the losses are high.
The easy solution would be to use Pmosfets for the high side.

You can read something like **broken link removed**

Also check this post to see the difference of proper gate voltage with the wrong gate voltage https://www.edaboard.com/threads/207965/#post878270

Alex

hi Alex thank for response and i will try this idea then come again

Can anyone upload a schematic view of full bridge inverter (3 level) proteus schematic ? i got many simulation outputs in matlab but not in proteus ,did driver circuit for each mosfet got pulses also correctly but output not coming ,upload or mail me (rajeshrameee@gmail.com) so that i will proceed with further circuits, thank yoy