Project Hub /Robotics & Autonomous Systems/Motor Drivers & Motion Control/Arduino DC Motor Speed Control using MOSFET Transistor

Intermediate

ARDUINO

₹500 – ₹1,500

3 – 6 Hours

Partial Kit

Arduino DC Motor Speed Control using MOSFET Transistor

Learn how to control the speed of a DC motor using an Arduino, a potentiometer, and a logic-level MOSFET transistor.

Originally published on CircuitDigest

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

Arduino UNO R3 Board (Compatible) – ATmega328P Microcontroller with USB Cable Rs. 999.00
10pcs - 220 ohm 1/4 W Resistor Set Rs. 39.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Cable for Arduino Nano (USB 2.0 A to USB 2.0 Mini B) 30cm Rs. 69.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

This list includes a generic resistor set as a placeholder — it is not matched to the exact value or part number this circuit needs. The correct one is specified on the original source page linked above; check it before buying.

We don't carry yet: Transistors (BC547 / 2N2222 / TIP / MOSFET)
Potentiometer / Trimpot

Browse all components

How It Works

This project enables you to control the rotational speed of a DC motor using an Arduino Uno. At the heart of the circuit is an IRLZ44N MOSFET, which acts as an electronic switch to handle the higher current required by the 12V DC motor, protecting the lower-power Arduino pins. A 10K ohm potentiometer is connected to an analog input on the Arduino to act as the user control interface. As you turn the potentiometer knob, the Arduino reads the changing analog voltage. Using the Arduino IDE software, the board processes this input and generates a Pulse Width Modulation (PWM) signal on a digital output pin. This PWM signal rapidly switches the MOSFET on and off at varying duty cycles. When the duty cycle is high, the motor receives more power and spins faster; when it is low, the motor receives less power and slows down. A 1k ohm resistor is placed in line with the MOSFET gate to limit control current and protect the digital pin. The entire circuit shares a common ground, powered by an external 12V power source for the motor while the Arduino is powered via the USB A to USB B cable during programming and debugging.

Why Build This

Build a foundational drivetrain speed controller for custom robotics and autonomous rovers.

Understand how to interface low-voltage microcontrollers with high-power external components using power MOSFETs.

Create adjustable mechanical devices and automated tools for school-level engineering design challenges.

Real-World Application

Motor speed controllers for robotics, electric toothbrushes, automated tools, and DIY mechanical devices.

Skills You'll Learn

PWM signal generation

analog sensor reading

MOSFET electronic switching

DC motor control

breadboard circuit prototyping

Safety Precautions

Use a flyback/freewheeling diode in parallel with inductive loads like DC motors to protect against reverse EMF spikes.

Technology Tags

ARDUINO

MOSFET

DC MOTOR

PWM

POTENTIOMETER

HARDWARE CONTROL

Frequently Asked Questions

Why can't I power the 12V DC motor directly from the Arduino 5V output pin?

The Arduino's internal regulator cannot supply enough current to drive a motor, and a 12V motor requires a higher voltage than the Arduino output pins provide. The Arduino is only used here to send control signals to the MOSFET, while the external 12V power source drives the motor.

What is the purpose of the 1k ohm resistor connected to the MOSFET?

The resistor limits the gate current flowing from the Arduino digital pin to the MOSFET, protecting the microcontroller from potential overcurrent conditions.

Why use a logic-level MOSFET like the IRLZ44N instead of a standard transistor?

Logic-level MOSFETs are designed to fully turn on with the 5V logic signals provided by an Arduino, ensuring efficient switching without overheating.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

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