I want to know the reason behind why this elements are connected in mosfet driver circuit. Basically I want to know the use of this elements .
elements are
(1)R1,R2 and diode in parallel with them
(2)R3,R4
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1\$\begingroup\$ have you read an introduction to MOSFET drivers / push-pull mosfet circuits? \$\endgroup\$– Marcus MüllerCommented Oct 20, 2020 at 21:06
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\$\begingroup\$ @anmol kumar: Regarding the goal of diodes and capacitors you can see this older post from mine:electronics.stackexchange.com/a/111852/22676 \$\endgroup\$– Dirceu Rodrigues JrCommented Oct 20, 2020 at 21:16
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1 Answer
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The resistor is there to control the gate charge current and through that the MOSFET off-to-on time. It's important for the whole bunch of reasons. My personal favorite is that MOSFET going on too fast creates current through the miller capacitance (D to G) and makes itself oscillating (sometimes kills the driver and other circuits, if totally out of control). Other reason is EMI. The resistor of course comes at a tradeoff: the MOSFETs gets hotter.
The diode is there to quickly discharge the MOSFET gate and turn it off.
Pull down resistors ensure that when the driver is off, the MOSFET's gate is discharged. Without it it can pick up noises, randomly open, destroy itself and the other one.