PWM Motor Driver with MOSFET H-Bridge and AVR ATmega8


Posted on Feb 6, 2014

Here is a very simple project of controlling a small DC-motor (taken from an old personal cassette player) with ATmega8. The ATmega8 is having three PWM channels, out of which two are used here. PWM waveforms are fed to MOSFET (RFD3055) H-bridge. Here, direction is controlled using a two-position toggle switch and speed of the motor is controlled by two push-buttons, one for increasing the speed and other for reducing. The schematic is geiven here (click on the image to enlarge): When switch SW1 is closed, OC1A channel is active which will feed the PWM signal to Q1 & Q4 MOSFETs. The OC1B pin will remain low keeping the Q3 & Q2 in OFF condition. When SW1 is toggled to open position, OC1A pin will become low, making Q1 & Q4 OFF and OC1B will feed the PWM signal to Q3 & Q2, resulting in the change in the direction of current flow through motor. Hence, motor rotation direction will change. The speed is controlled by Push-buttons S2 & S3. Pressing S2 will increase the speed in fixed steps. Similarly, pressing S3 will reduce the speed in fixed steps.


PWM Motor Driver with MOSFET H-Bridge and AVR ATmega8
Click here to download the full size of the above Circuit.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Speech amplifier circuit
    Make a singing MSP430 microcontroller
    Keep The Ramp right
    ISL6308A Three-Phase Buck PWM Controller with High Current Integrated MOSFET Drivers
    BJT H-bridge Circuit Details



    Top