How to drive NMOS (IRF540n) from PWM?

[usama_ali]

Hi experts!
I am new here. kindly help me to solve my issue.
currently I am working on Class D amplifier. I have generated two PWM which are inverted versions of each other (please see attached pic) and now i want to drive two NMOS (IR540N) from these PWM's. Can u suggest me how can I achieve this? waiting for your kind response

 

[Audioguru]

You need a push-pull output. Two of the same kind of Mosfets can do push-push or pull-pull but cannot do both.
An IRF540 or IRL540 is N-channel that has a drain that can go down to ground but it does not go positive. A P-channel Mosfet is needed for its drain to go up to the positive supply. The P-channel Mosfet needs a level changer.

Read the datasheet. The datasheet for the IRF540 shows that its gate needs 10V to turn on fully, not just 5V. It shows that some IRF540 Mosfets barely turn on (0.25mA) when the gate-source is 4V.
Use an IRL540 (see the "L"?) which needs only 4.5V to turn on fully.

Does your circuit have some "dead time" between the pulses so that one Mosfet can turn on after the other Mosfet is off?

EDIT: A Mosfet driver IC can use two N-channel Mosfets since it boosts the gate voltage so that the upper Mosfet can be a source follower and have its source go to the positive supply when its gate voltage is boosted to be 5V or 10v higher than the positive supply.
Dead time avoids having both Mosfets turned on at the same time producing a massive shoot-through current from the power supply.