L293D Motor Driver: Use Cases, Limitations and Solutions
The L293D is small but powerful motor drivers for low powerful DC motors. As it is cheap and reliable, it’s a favorite in the field of robotics and DIY. It comes with some limitations which might frustrate you.
Use cases:
– Small DC Motors: Great for wheels on little robots or robotic arms.
– Stepper Motors: Can handle basic CNC or 3D printer movements.
– Simple Automation: Think small doors or conveyor belts—low power, repetitive tasks.
– DIY RC Projects: Perfect for small RC cars with basic functionality.
When L293D is not useful
The L293D isn’t the best choice in every scenario. Here’s where it might let you down:
-High-Power Motors: If your motor pulls more than 600mA continuously, the L293D can struggle to keep up. For more power, look at options like the L298N or a MOSFET driver.
– Battery Efficiency: The L293D has a noticeable voltage drop (1.2V – 2V), which drains batteries faster. If you’re building something that needs to conserve power, consider a more efficient driver.
– Precision Control: While it does support PWM (speed control), it’s not super smooth at low speeds. For applications that need fine control, other drivers like the TB6612FNG might be better.
Common Issues faced and their solutions
1. Voltage Drop and too much Heat buiding
The L293D’s design causes some power loss, which can heat things up. Solution? Use a slightly higher power supply and add a heatsink or fan if needed.
2. Limited Current Output
For motors needing more than 600mA, the L293D may overheat or shut down. Stick to low-current motors or use a higher-rated driver.
3. PWM Challenges
It supports basic PWM, but not always smoothly. Experimenting with higher frequencies may reduce motor stuttering, or switch to a more PWM-friendly driver like the TB6612FNG.
4. Extra Protection for High Voltage
The L293D handles basic back EMF, but for high-voltage motors, adding external diodes across the motor terminals can provide extra protection.
Better Alternatives for High-Power Projects
If you need more power, try these:
– L298N: Works up to 2A per motor, though it also has a voltage drop.
– TB6612FNG: A more efficient, MOSFET-based choice for battery-powered setups.
– DRV8833: Compact and efficient for low-power motors with solid power management.
Conclusion
The L293D is versatile and beginner-friendly, making it a great choice for small robotics and DIY automation. Just remember its limits, and don’t hesitate to switch to a stronger driver if your project needs it. With a few simple adjustments, the L293D can be a reliable partner in your electronics projects.
