The transistor Q5 can be omitted, but I want to achieve non-inverting PWM signal.The transistor Q4 is needed to provide the ground for the transistor Q3 (PNP), because the gate of the MOSFET is charged with 12V, and the MCU is only 5V tolerant.The capacitor C1 (100uF) is used to reduce the spikes from the fast PWM switching, and the capacitor C2 is used to smooth the power near BJT transistors (not sure if it is needed).The base resistor of the BJT transistors is 2.2k ohms, which in my opinion is enough to open the transistors to charge the gate (12V/2200R*30hFE=0.16A) of the MOSFET, and also is not too low to dissipate too much power (12^2V/2200R=0.065W).But probably there is not much power, so one resistor should be enough. I decided to use 2 gate resistors (R3 and R2) with nominal of 100 Ohms for 2 reasons: The main reason is to reduce the current passed via the transistors, and the second reason is to split the power dissipation (charge, discharge) between 2 resistors.The transistors Q2 (charge) and Q3 (discharge) are push-pull transistors, NPN is used to charge the gate of the MOSFET with high voltage (12V), and PNP to discharge it.I'll explain the schematic below, so if I do something wrong, please correct me:
TRANSISTOR GATE DRIVER CIRCUIT HOW TO
I'm trying to learn how to build one individually (for a beginner, not perfect). Please do not recommend using a commercial MOSFET driver, I know they are cheap and easy to use. For my needs, the maximum load of the MOSFET is 1A (but the driver should work fine even with higher load), and the PWM frequency is 245 Hz (5V). I'm trying to create a circuit for controlling the gate of a MOSFET (IRFZ44N). Please take a look at my schematic, are there any mistakes or recommendations? I'm trying to build a MOSFET driver, I am new in electronics, and specially in controlling MOSFETs.
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