The circuit shown below is of a DC motor driver circuit based on the IC TC4424 from Microchip. TC 4424 is a dual MOSFET driver that can be used in a variety of applications like SMPS, pulse transformer drivers, line drivers, motor drivers etc.
The speed and of direction rotation of the motor depends on the logic levels of pin 2 and 4. The speed of rotation of the motor is proportional to the duty cycle of the PWM signal fed to pin 2. If the pin 4 is held at logic 0 the motor will run in the forward direction and if it is held at logic 1, then the motor will run in the reverse direction.
In the circuit, resistors R1 and R2 are pull up resistors. D1 and D4 protect the IC chip from under voltages (negative back emf). D2 and D3 provide a safe path for the motors positive back emf to dissipate and safeguard the IC. Capacitors C1 and C2 reduce electrical noises.
- The circuit can be assembled on a Vero board.
- The circuit can be powered from anything between 10 to 18V DC depending on the voltage rating of the motor used.
- Do not use a motor that consumes more than 100mA of current.