#695 ATtiny PMW Motor Control
Variable speed PWM motor control with an ATtiny85.
Notes
Demonstrates using a PWM signal to control a DC motor, hence its speed.
PMW is generated by an ATtiny85 with the duty cycle set based on reading a variable resistor.
The PWM signal switches a low-side n-channel FET to control the motor.
A fly-back diode is placed across the motor to drain any voltage spike as the motor load is switched
In the demonstration circuit, the ATtiny85 and motor are powered from the same 5V supply. Some hefty capacitors are added to smooth the supply and prevent the motor from disturbing the power supply to the microprocessor.
The following scope trace shows the PWM out (CH1 Yellow) compared to the variable resistor input voltage (CH2 Blue):
Circuit Design
