Welcome to Synthiam!

The easiest way to program the most powerful robots. Use technologies by leading industry experts. ARC is a free-to-use robot programming software that makes servo automation, computer vision, autonomous navigation, and artificial intelligence easy.

Get Started
Asked — Edited

Wiring Up Two H-Bridges


I wired two h-bridges (from the EZ-Robot store) to the 4 motors on my Dagu 4WD Thumper. I wired one h-bridge to the right side wheels (each wheel gets one of the dual outputs from the bridge). And the other h-bridge to the left side wheels.

My question is: can one digital output from the EZ-B board be used to drive two digital inputs on the h-bridge? Specifically I want to jumper IN1 to IN3 and IN2 to IN4 and drive each pair with an output from the EZ-B board. This way the right-side wheels will move in sync but will have separate power sources. Same for the left-side wheels.



Upgrade to ARC Pro

Synthiam ARC Pro is a cool new tool that will help unleash your creativity with programming robots in just seconds!

AI Support Bot
Related Content
Based on your post activity, we found some content that may be interesting to you. Explore these other tutorials and community conversations.
Connect the one HBridge to the front wheels (left and right). And the second HBridge to the rear wheels (left and right)

The HBridge controls Left and Right motors, not both on the same side.

Then, combine the input's of the hbridge from the EZ-B between the two. So essentially, you end up with one HBridge being controlled by the same 4 digital ports.
Hi DJ,

Why does it work better to do it that way? My way allows me to jumper together the inputs on one H-bridge to combine the input signals (IN1 to IN3 and IN2 to IN4). If I understand your recommendation correctly, I would need to connect the IN1 on one bridge to the IN1 on the other bridge, IN2 to IN2, and so on. So I would need to run 4 wires between the two controller boards. Versus my way where I don't have to run any wires between the two boards. Also, with my way I can control the speed of each side by running one PWM signal to each board and jumper the two speed pins together on the board.

Ah, I see what you have done - smart. So two wires from the EZ-B are running to an HBridge. That will work:) I never considered that before! So you'll need to connect IN1 and IN3 and IN2 and IN4 together on each HBridge.

Looks like you answered your own question:)
OK cool! I thought I was missing something. :D

On a related issue, what position should the switch S1 be in if I want to use the +5V from the EZ-B as the digital source? Should the "5V LED" be on or off?

For reference, I have an 11.4V battery dedicated to running the motors (hooked up to Vcc and GND) and a separate 7.6V battery for the EZ-B. I wired the EZ-B D0 +5V pin to the 5V input on the H-bridge board.