Robotics tool kit series - H bridge L293D Arduino shield

The most common hardware needed in almost any robot involving DC/Stepper Motor is a motor driver shield which talks with the microcontroller which is mostly Arduino for starters.

A shield is a hardware board that sits on another hardware board with pins and extends the capability.

A motor driver shield is needed because a DC /Stepper motor by default does not know to regulate its speed nor it can understand direction. A motor shield like this works on the concept of an H-bridge in electronics.

An H-bridge is an electronic circuit that enables a voltage to be applied across a load in either direction. These circuits are often used in robotics and other applications to allow DC motors to run forwards and backwards.

This shield should be mounted on top of Arduino UNO. This shield is capable of running 4 dc motor or 2 stepper motors along with two servos.


An H-bridge is an electronic circuit that enables a voltage to be applied across a load in either direction


It needs to be programmed using the Arduino IDE. In case you have bought this as part of our kit then coding is not needed.

The shield needs the jumper to be removed near the power side in case you are providing it with external power.

We recommend that you use different power sources for Arduino Uno and the shield.

Motor driver L293D | Robotics blog

There is a slot marked as M1,M2,M3 & M4. All four have in turn two slots for the + & -. Motors needs to be connected to this. There is a Green power led and a reset button on top. The led indicates power and the reset button will run the code again.

Frequencies for channel M1 & M2 are:

  • MOTOR12_64KHZ

  • MOTOR12_8KHZ

  • MOTOR12_2KHZ

  • MOTOR12_1KHZ

Frequencies for channel M3 & M4 are:

  • MOTOR34_64KHZ

  • MOTOR34_8KHZ

  • MOTOR34_1KHZ

Library to use:

AF_Motor Arduino library is to be used for this hardware. Download link is at -

Download Adafruit Motor driver for L293D

There are other H bridges that are available like L298 but if you are using Arduino we recommend the L293 shield as its much easier to code, connect and test than L298 (Our personal view - if you like L298 it's great as well).

There is also an updated version available to this driver which uses the TB6612 MOSFET drivers. The link is below.

Adafruit Motor shield V2

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