The direction and speed of DC motors and stepper motors are controlled by the flexible H-bridge motor driver integrated circuit L293D, which is extensively utilized in robotics and automation.
By flipping the polarity of the voltage supplied to the motor terminals, an H-bridge design enables the control of a motors rotation direction.
This IC is appropriate for a wide range of applications, from basic robotics projects to more intricate systems, since it can operate two motors concurrently and provide a maximum output current of 600 mA per channel.
Built-in diodes in the L293D provide dependable operation and extended life by guarding against back EMF produced when motors are turned off.
The L293D is a popular choice for both professionals and enthusiasts because to its user-friendly interface and seamless integration with popular microcontrollers such as Arduino and Raspberry Pi.
Users may accomplish accurate movement in their projects and effectively regulate motor speed using PWM (Pulse Width Modulation) by employing the L293D.
Circuit Working:
Parts List:
| Component | Quantity |
|---|---|
| DC Motors | 2 |
| IC L293D | 1 |
| Diodes 1N4001 | 4 |
To enable the motor to run as needed, the H-Bridge motor driver regulates the power and signals to the motor.
A high-current driver capable of managing two motors simultaneously is the L293D IC.
It functions with voltages ranging from 4.5V to 36V and can deliver bidirectional current up to 600 mA.
The L293D has characteristics including excellent noise immunity and inbuilt ESD protection, and it comes in a 16-pin package.
This motor driver has a simple circuit design that just needs four extra diodes for additional protection.
With this configuration, two different motors may be powered by two different input signals.
Motor 1s input is connected to pins 2 and 7 of IC L293D , and its output is connected to pins 3 and 6.
Likewise, Motor 2 is connected to pins 10 and 15 of IC L293D , while its output is connected to pins 11 and 14.
The purpose of the diodes D1–D4 is to safeguard against motor reverse voltage.
Formulas:
The relevant formulas for Exploring the L293D H-Bridge Motor Driver Circuit is mentioned below:
Motor Speed Control:
Pulse Width Modulation, or PWM, is a technique for controlling the speed of the motors.
The average voltage Vavg across the motor may be written as follows:
Vavg = Vsupply × D / 100
where,
- D is the duty cycle percentage.
Power Calculations:
The following formula may be used to determine the power used by each motor:
P = Vmotor × Imotor
where,
- Vmotor is the voltage across the motor, and
- Imotor is the current flowing through it.
Current Ratings:
Verify that the current ratings do not go over the L293Ds capabilities, which include a 600 mA per channel maximum.
One may compute the total power from the power supply as follows:
Ptotal = Vsupply × Itotal
where,
- Itotal is the sum of currents through both motors.
Thermal Considerations:
The following tools may be used to track the power dissipation in the L293D:
Pdissipation = (Vsupply − Vmotor) × Imotor
This is important to ensure the IC does not overheat.
Note:
Verify all connections, and if running at greater currents, take suitable heatsink into consideration.
With this configuration, the L293D H-Bridge motor driver ought to be able to effectively control two motors.
How to Build:
For Exploring the L293D H-Bridge Motor Driver Circuit follow the below mentioned construction steps for connections:
- Gather all the components as mentioned in the above circuit diagram
- Connect first pin of Motor1 to pin 3 of IC L293D
- Connect second pin of Motor1 to pin 6 of IC L293D
- Connect first pin of Motor2 to pin 11 of IC L293D
- Connect second pin of Motor2 to pin 14 of IC L293D
- Connect the cathodes of individual diodes D1 to D4 with each of the terminals of the two motors and connect all the anodes of the diodes with the GND.
- Connect first pin of input Motor1 to pin 2 of IC L293D
- Connect second pin of input Motor1 pin 7 of IC L293D
- Connect first pin of input Motor2 to pin 10 of IC L293D
- Connect second pin of input Motor2 to pin 15 of IC L293D
- Connect pins 4, 5, 12, 13 to GND of IC L293D
- Connect pin 1,8 , and 9 of IC L293D to +5V positive supply.
- Connect pin 16 of IC L293D to +12V of positive supply
Conclusion:
To conclude, the L293D H-Bridge motor driver circuit provides a practical way to easily control two DC motors.
Its inherent safety, simple circuit design, and capacity to supply bidirectional driving currents make it a well-liked option for a range of robotics and automation applications.
You may get dependable motor control with less components by using this integrated circuit into your designs, guaranteeing effective performance in your applications.
References:
A general question regarding a simple DC Motor combined with an H-Bridge (L293D)