In this section, you will see the interface of DC motor with motor driver IC L293D, and three possible connection cases.
Here we are using an L293D IC with a single input and single output means, as we give signal HIGH (logic ‘1’) or LOW (logic ‘0’) to pin number 2 (IN1) of IC we will get the same signal at the output HIGH and LOW respectively.
INTERFACE OF DC MOTOR WITH MOTOR DRIVER IC L293D
CASE 1: MOTOR SINGLE TERMINAL CONNECTION WITH IC
As you can see, one terminal of the motor is connected at ground, so it will work when it gets a HIGH signal to the other end.
But before this, we need to make sure some connections like,
- Connect VSS / VCC 1 (pin 16) and VS / VCC 2 (pin 8) to HIGH (+5V)
- Enable pin EN1 (pin 1) to +5V.
(We connected both Enable EN1, EN2 you can connect the one you need, EN1 for IN1, IN2 & EN2 for IN3, IN4 where EN is enable & IN is input)
- Ground Pin 4, 5, 12, 13 (although here only two shown, but in real-time there are 4 pins)
CASE 2: MOTOR BOTH TERMINAL CONNECTION WITH IC
Now we connect both terminals of the motor to the output pin of IC, and two input logic state for the IC, so that we can control the motor in both directions such as, clockwise and anti-clockwise.
As we give logic 0 at both input and motor does not work due to zero potential difference (difference between voltages), in the same manner, it will not work if we apply logic 1 for both because here also the potential difference is zero.
CASE 3: CONTROL HIGH VOLTAGE MOTOR USING LOW VOLTAGE SIGNAL
L293D IC can be used for motors that work on high voltage means more than 5V such as 12V, 24V up to 36V in ideal condition according to the L293D IC datasheet.
For this, you need to change the voltage applied at VS / VCC2 (pin 8) of IC, see below the effect
With this type of connection, we can say, maximum we can connect 2 motors using 1 L293D IC to control them in both directions.