How to Use L293 DC and Stepper motro driver: Examples, Pinouts, and Specs

The L293 is a dual H-bridge motor driver IC designed to control DC and stepper motors. It enables bidirectional control, allowing motors to rotate in both clockwise and counterclockwise directions. With the ability to drive two motors simultaneously, the L293 is a versatile component widely used in robotics, automation, and motor control applications. It can handle up to 600mA of current per channel and operates at a wide voltage range, making it suitable for a variety of projects.

• Robotics (e.g., motorized robots, robotic arms)
• Automation systems
• Motorized toys
• Conveyor belts
• Stepper motor control for CNC machines or 3D printers

Below are the key technical details of the L293 motor driver IC:

The L293 IC has 16 pins, as described in the table below:

1. Power Connections:

   • Connect Vcc1 (pin 16) to a 5V power supply for the logic circuitry.
   • Connect Vcc2 (pin 8) to the motor power supply (4.5V to 36V, depending on the motor).
   • Connect all GND pins (pins 4, 5, 12, 13) to the ground of the power supply.

2. Motor Connections:

   • For motor 1, connect its terminals to Output 1 (pin 3) and Output 2 (pin 6).
   • For motor 2, connect its terminals to Output 3 (pin 11) and Output 4 (pin 14).

3. Control Logic:

   • Use the Input pins (2, 7 for motor 1; 10, 15 for motor 2) to control the direction of the motors.
   • Set the Enable pins (1 for motor 1; 9 for motor 2) high to enable the respective H-bridge.

4. Direction Control:

   • To rotate a motor in one direction, set one Input pin high and the other low.
   • To reverse the direction, swap the logic levels of the Input pins.

5. Enable/Disable Motors:

   • Set the Enable pin low to disable the motor (outputs will be in high-impedance state).

Below is an example Arduino sketch to control a DC motor using the L293:

// Define L293 pins connected to Arduino
const int enablePin = 9;  // Enable pin for motor 1
const int input1 = 7;     // Input 1 for motor 1
const int input2 = 8;     // Input 2 for motor 1

void setup() {
  // Set pin modes
  pinMode(enablePin, OUTPUT);
  pinMode(input1, OUTPUT);
  pinMode(input2, OUTPUT);

  // Initialize motor in stopped state
  digitalWrite(enablePin, LOW);  // Disable motor
  digitalWrite(input1, LOW);     // Set input1 low
  digitalWrite(input2, LOW);     // Set input2 low
}

void loop() {
  // Rotate motor clockwise
  digitalWrite(enablePin, HIGH);  // Enable motor
  digitalWrite(input1, HIGH);     // Set input1 high
  digitalWrite(input2, LOW);      // Set input2 low
  delay(2000);                    // Run motor for 2 seconds

  // Rotate motor counterclockwise
  digitalWrite(input1, LOW);      // Set input1 low
  digitalWrite(input2, HIGH);     // Set input2 high
  delay(2000);                    // Run motor for 2 seconds

  // Stop motor
  digitalWrite(enablePin, LOW);   // Disable motor
  delay(2000);                    // Wait for 2 seconds
}

• Use a heat sink if the IC gets too hot during operation.
• Add flyback diodes across the motor terminals to protect the IC from voltage spikes.
• Ensure the motor's current requirements do not exceed the L293's maximum ratings.

1. Motor Not Spinning:

   • Check if the Enable pin is set high.
   • Verify the power supply connections to Vcc1 and Vcc2.
   • Ensure the Input pins are receiving the correct logic levels.

2. Motor Spins in Only One Direction:

   • Verify the connections to the Input pins.
   • Check if one of the Input pins is stuck at a fixed logic level.

3. IC Overheating:

   • Ensure the motor's current does not exceed 600mA per channel.
   • Use a heat sink or cooling fan to dissipate heat.

4. No Output Voltage on Motor Terminals:

   • Confirm that the Enable pin is high.
   • Check for loose or incorrect wiring.

Q: Can the L293 drive stepper motors?
A: Yes, the L293 can drive stepper motors by controlling the sequence of the Input pins. Each H-bridge can control one coil of the stepper motor.

Q: What is the difference between Vcc1 and Vcc2?
A: Vcc1 powers the logic circuitry (4.5V to 7V), while Vcc2 powers the motors (4.5V to 36V).

Q: Can I use the L293 with a 3.3V microcontroller?
A: The L293 requires a minimum logic voltage of 4.5V, so it is not directly compatible with 3.3V logic. Use a level shifter or a 5V microcontroller.

Q: How many motors can the L293 control?
A: The L293 can control two DC motors or one stepper motor.