How to Use L293D Motor Driver: Examples, Pinouts, and Specs

Design with L293D Motor Driver in Cirkit Designer

Introduction

The L293D is a dual H-bridge motor driver IC designed to control the direction and speed of DC motors and stepper motors. It is capable of driving two motors simultaneously, making it an essential component in robotics, automation, and motor control projects. The IC can handle bidirectional control of motors, allowing for forward and reverse motion, and supports pulse-width modulation (PWM) for speed control. Its compact design and ease of use make it a popular choice for hobbyists and professionals alike.

Explore Projects Built with L293D Motor Driver

Arduino-Controlled Dual DC Motor Driver with Hall Effect Sensors and Indicator LEDs

This circuit controls two DC motors using an L293D motor driver, with an Arduino UNO as the microcontroller. The Arduino reads inputs from three Hall sensors and controls the motors' direction based on the sensors' states, while also indicating the sensors' status through three LEDs. Each LED and Hall sensor is connected to the Arduino with a current-limiting resistor, and the motors' operation is dependent on the Hall sensors' signals.

Open Project in Cirkit Designer

Arduino UNO Controlled Obstacle Avoiding Robot with L293D Motor Driver and Ultrasonic Sensor

This circuit is designed to control a robot with four DC motors for movement, an ultrasonic sensor for distance measurement, and a servo motor to direct the sensor. The L293D driver shield interfaces with the motors, while the Arduino UNO microcontroller runs the embedded code to process sensor data and control motor speeds and directions. An LCD display is included for output, and power is supplied by a 4 x AAA battery mount.

Open Project in Cirkit Designer

Bluetooth-Controlled Robotic Car with L293D Motor Driver and LED Indicators

This circuit is a motor control system that uses an L293D driver shield to control four hobby gearmotors, with each motor connected to an LED and a resistor for status indication. The system is powered by a 2x 18650 battery pack and includes an HC-05 Bluetooth module for wireless communication.

Open Project in Cirkit Designer

Arduino-Controlled Robotics Platform with Dual L298N Motor Drivers and QMC5883L Magnetometer

This circuit is designed to control multiple DC motors and a servomotor using an Arduino UNO microcontroller. The L298N motor drivers are used to drive the DC motors, with control signals provided by the Arduino. Additionally, the circuit includes a QMC5883L magnetometer for magnetic field measurement, interfaced with the Arduino via I2C, and a servomotor controlled directly by an Arduino PWM output.

Open Project in Cirkit Designer

Common Applications

Robotics (e.g., controlling robot wheels)
Conveyor belt systems
Automated gates and doors
Stepper motor control in CNC machines
DIY motorized projects

Technical Specifications

The L293D is a robust IC with the following key specifications:

Parameter	Value
Operating Voltage	4.5V to 36V
Logic Input Voltage	0V to 7V
Output Current (per channel)	600mA (continuous), 1.2A (peak)
Number of Channels	2 (dual H-bridge)
Maximum Power Dissipation	5W
Enable Pins	Supports PWM for speed control
Operating Temperature	-40°C to +150°C

Pin Configuration and Descriptions

The L293D has 16 pins, as described in the table below:

Pin Number	Pin Name	Description
1	Enable 1 (EN1)	Enables/Disables Motor 1. Can be used for PWM speed control.
2	Input 1 (IN1)	Logic input to control Motor 1 direction.
3	Output 1 (OUT1)	Output connected to one terminal of Motor 1.
4	GND	Ground (common ground for logic and motor power).
5	GND	Ground (common ground for logic and motor power).
6	Output 2 (OUT2)	Output connected to the other terminal of Motor 1.
7	Input 2 (IN2)	Logic input to control Motor 1 direction.
8	Vcc2 (Motor Vcc)	Power supply for motors (4.5V to 36V).
9	Enable 2 (EN2)	Enables/Disables Motor 2. Can be used for PWM speed control.
10	Input 3 (IN3)	Logic input to control Motor 2 direction.
11	Output 3 (OUT3)	Output connected to one terminal of Motor 2.
12	GND	Ground (common ground for logic and motor power).
13	GND	Ground (common ground for logic and motor power).
14	Output 4 (OUT4)	Output connected to the other terminal of Motor 2.
15	Input 4 (IN4)	Logic input to control Motor 2 direction.
16	Vcc1 (Logic Vcc)	Power supply for logic circuit (5V).

Usage Instructions

How to Use the L293D in a Circuit

Power Connections:
- Connect Vcc1 (Pin 16) to a 5V power supply for the logic circuit.
- 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.
Motor Connections:
- Connect the motor terminals to the output pins (OUT1, OUT2 for Motor 1; OUT3, OUT4 for Motor 2).
Control Logic:
- Use the input pins (IN1, IN2 for Motor 1; IN3, IN4 for Motor 2) to control the direction of the motors.
- Use the enable pins (EN1 for Motor 1; EN2 for Motor 2) to enable/disable the motors or to control speed using PWM.
Direction Control:
- Set the input pins as follows to control motor direction:
  - IN1 = HIGH, IN2 = LOW: Motor 1 moves forward.
  - IN1 = LOW, IN2 = HIGH: Motor 1 moves backward.
  - IN1 = IN2: Motor 1 stops.
Speed Control:
- Apply a PWM signal to the enable pins (EN1 or EN2) to control motor speed.

Example: Connecting L293D to Arduino UNO

Below is an example of how to control a DC motor using the L293D and Arduino UNO:

// Define motor control pins
const int ENA = 9;  // Enable pin for Motor 1 (connected to PWM pin)
const int IN1 = 2;  // Input 1 for Motor 1
const int IN2 = 3;  // Input 2 for Motor 1

void setup() {
  // Set motor control pins as outputs
  pinMode(ENA, OUTPUT);
  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);
}

void loop() {
  // Move motor forward
  digitalWrite(IN1, HIGH);  // Set IN1 HIGH
  digitalWrite(IN2, LOW);   // Set IN2 LOW
  analogWrite(ENA, 200);    // Set speed (0-255)

  delay(2000);              // Run for 2 seconds

  // Stop motor
  digitalWrite(IN1, LOW);   // Set IN1 LOW
  digitalWrite(IN2, LOW);   // Set IN2 LOW
  analogWrite(ENA, 0);      // Set speed to 0

  delay(1000);              // Wait for 1 second

  // Move motor backward
  digitalWrite(IN1, LOW);   // Set IN1 LOW
  digitalWrite(IN2, HIGH);  // Set IN2 HIGH
  analogWrite(ENA, 150);    // Set speed (0-255)

  delay(2000);              // Run for 2 seconds

  // Stop motor
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, LOW);
  analogWrite(ENA, 0);

  delay(1000);              // Wait for 1 second
}

Important Considerations

Ensure the motor power supply voltage matches the motor's specifications.
Use a heat sink if the IC gets too hot during operation.
Avoid exceeding the maximum current rating to prevent damage to the IC.
Decouple the power supply with capacitors to reduce noise and voltage spikes.

Troubleshooting and FAQs

Common Issues and Solutions

Motor Not Running:
- Check power supply connections to Vcc1 and Vcc2.
- Ensure the enable pin (EN1 or EN2) is set to HIGH or receiving a PWM signal.
- Verify the input logic pins (IN1, IN2, etc.) are correctly configured.
Motor Running in the Wrong Direction:
- Reverse the logic levels on the input pins (e.g., swap IN1 and IN2).
IC Overheating:
- Ensure the current drawn by the motor does not exceed 600mA.
- Use a heat sink or reduce the motor load.
PWM Speed Control Not Working:
- Verify the PWM signal is being sent to the correct enable pin.
- Check the PWM frequency and duty cycle settings in your microcontroller code.

FAQs

Q: Can the L293D drive stepper motors?
A: Yes, the L293D can drive stepper motors by controlling the sequence of inputs to the H-bridges.

Q: Can I use the L293D with a 3.3V microcontroller?
A: The L293D requires a minimum logic voltage of 4.5V. Use a level shifter or a 5V microcontroller for compatibility.

Q: How many motors can the L293D control?
A: The L293D can control two DC motors or one stepper motor.