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PWM
Fake an analog level with a digital pin: a fixed-frequency square wave whose duty cycle sets the average voltage, built on a timer and used for LEDs, motors, and servos.
20 min read
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What is PWM and how does it produce an "analog" output from a digital pin?How is PWM generated using a timer?What's the tradeoff between PWM frequency and duty-cycle resolution?Why can't you drive a motor directly from a PWM-capable GPIO pin?How does PWM control a hobby servo, and how is that different from LED dimming?What is dead-time in a complementary PWM pair, and why does an H-bridge need it?Your PWM-controlled LED looks steady to the eye but flickers badly on camera video. What's going on and how do you fix it?
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