Introduction

The MT3608 is a popular step-up (boost) DC-DC converter IC that can efficiently convert lower voltages (like 5V from USB) to 12V. Here’s how to create a 12V boost converter using the MT3608 that plugs into a USB port.

For Full Project:

https://electronicsworkshops.com/2025/01/27/12v-boost-converter-usb-plug-using-mt3608/

12V Boost Converter USB Plug Using MT3608

MT3608

The MT3608 is a constant frequency, current mode step-up converter typically used in small, low-power applications. It’s designed to boost lower voltages to higher voltages efficiently.

Key Features:

Integrated 80mΩ Power MOSFET

Input Voltage: 2V to 24V

Adjustable Output Voltage: up to 28V

Fixed Switching Frequency: 1.2MHz, which allows for smaller and lower cost capacitors and inductors.

Internal 4A Switch Current Limit

Automatic Pulse Frequency Modulation (PFM) Mode at Light Loads for higher efficiency

Internal soft-start to limit inrush current

Thermal overload protection

Available in a small 6-Pin SOT-23 package

Efficiency up to 97%

Applications

Battery-powered equipment (portable speakers, digital cameras)

Set-top boxes

LCD bias supply

DSL and cable modems and routers

Networking cards powered from PCI or PCI express slots

LED drivers

Power modules

Medical Equipment

For Full Project:

https://electronicsworkshops.com/2025/01/27/12v-boost-converter-usb-plug-using-mt3608/

Key Specifications

Input Voltage: 2V – 24V

Adjustable Output Voltage: up to 28V

Switching Frequency: 1.2 MHz

Maximum Output Current: 2A (though sustained use at 1A is recommended by some sources)

Operating Temperature: -40°C to +85°

Circuit Description

USB Input (5V) → MT3608 Boost Converter → Adjust to 12V Output

The USB plug provides 5V input to the MT3608.

The MT3608 steps this up to 12V.

The output can power small 12V devices like LED strips, relays, fans, routers (low current), or Arduino shields

Circuit Diagram MT3608

USB Connection:

Connect the USB plug’s +5V (usually red wire) to the input of your circuit

Connect the USB ground (usually black wire) to your circuit ground

Input Filtering:

Add a 10μF capacitor between input +5V and ground

MT3608 Connections:

Vin pin to USB +5V

GND pin to USB ground

SW pin to inductor

FB pin to voltage divider

Output Section:

Connect the inductor to the anode of the Schottky diode

Cathode of diode is your 12V output

Add output capacitor (22μF) between 12V and ground

Feedback Voltage Divider:

Calculate resistors for 12V output (FB voltage is typically 0.6V)

R1 = (Vout/Vfb – 1) × R2

R1=62k R2= 3.3k

PCB Files

3D files

Conclusion

This simple circuit will allow you to power 12V devices from a standard USB port, useful for small electronics projects or low-power 12V devices.

For Full Project:

https://electronicsworkshops.com/2025/01/27/12v-boost-converter-usb-plug-using-mt3608/