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- An Arduino pin can deliver only ~40mA current.
- DC motors like the one we use draw several 100s of mA when loaded.
- We need a switch/ current amplifier to drive the motor based on the signals from the Arduino.
- Arduino -> Driver -> Motor.
- A motor driver allowing bidirectional drive is called an H-bridge
- L293D is a popular motor driver.
- L293D has 4 switches (half H-bridges). This can be used to drive 4 motors unidirectionally or 2 motors bidirectionally
- Note that the enables for inputs 1 & 2 are combined (you probably won’t need it, but enable should be high for the PWM signal from Arduino to have any effect). Ditto for enables of inputs 3 & 4
- L293D has freewheeling/flyback diodes are already connected inside the chip and need not be connected externally
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