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Hey everyone, what’s up?

So here’s something awesome, a Microrobot Base that is equipped with a few FETs to make an H-Bridge for driving two motors.

These FETs are used for driving small gear micromotors with a 3.7V Li-ion cell.

Apparently, common motor drivers like L293D work with a minimum voltage of 4.5V to 36V, so it wouldn’t work with our current setup, and we need to increase the battery voltage from a single 3.7V cell to a battery pack composed of two or three cells in series. Electrically, this is ideal, but because we are making a two-wheeled small robot, using a 3-cell battery pack will increase the weight and size.

The best option here was to make a DIY motor driver from scratch using Mosfets.

So I prepared a simple H-bridge setup that utilizes four N-channel MOSFETs connected in an H configuration for controlling each motor. Two motors are used, so two H-bridges were made with 8 FETs.

This setup is just a base for the upcoming robot project. This Instructables is about how this Dual Motor Driver Base works and how it’s prepared step by step, so let’s get started.

Supplies
Following are the materials used in this built-

- AO3400 N channel Mosfet SOT23 Package
- Custom PCB
- 10K resistors 0603 Package
- 2R 1206 package
- JST connectors
- Vertical Header pin male connector
- Micro gear motor
- 3D printed Motor Holder”

Link to article