H-Bridge

L293D H-Bridge, used on esieabots from 2020 to 2022

Your esieabot is equipped with a bridge that allows it to control its 2 DC motors in all directions. On esieabots from 2020 to 2022, it is an L293D from STMicroelectronics. On esieabots from 2023 and newer, it is a DRV8411 from Texas Instruments, integrated into the add-on board. The components differ greatly in terms of performance, but their operation is very similar.

Operation

An H-bridge is a component that allows a motor to rotate in two directions. On the esieabot, the H-bridge is “dual” because it can control 2 motors at the same time.

Depending on which inputs are activated, the voltage will go in one direction or the other, causing the motors to rotate in one direction or the other.

Cyril BUTTAY, CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons

Connections

For each motor, the following inputs and outputs must be connected:

• “Enable” input: enables or disables a motor, only present on the L293D, on esieabot models from 2020 to 2022 inclusive

• “Input 1 (or 3)” input: activates the motor in one direction

• “Input 2 (or 4)” input: activates the motor in the other direction

• “Output 1 (or 3)” output: one of the motor terminals

• “Output 2 (or 4)” output: the other motor terminal

• “Fault” output: detects a problem with the H-bridge, such as overcurrent or overtemperature, only present on the DRV8411, on esieabot models from 2023 and newer

Note

Note that there is no defined direction through the H-bridge. The motor’s + and - terminals as well as the forward/backward direction are purely arbitrary.

Note

If you are using an add-on board, you can find the GPIOs used in its documentation.

Technical Specifications

The complete datasheet for the L293D (esieabot 2020 to 2022) can be found here: https://www.st.com/resource/en/datasheet/l293d.pdf.

The complete datasheet for the DRV8411 (esieabot 2023 and newer) can be found here: https://www.ti.com/lit/ds/symlink/drv8411.pdf.