DC 6V–40V to 5V 3A Dual USB Step-Down Converter Module

Power two USB devices simultaneously from solar panels, vehicles, or any DC source between 6V and 40V. This compact DC-DC step-down (buck) converter module delivers a stable 5V/3A output with up to 92% conversion efficiency — keeping your phones, tablets, and other USB gadgets charged wherever you are. Made in Mainland China.

Key Features

High Efficiency: Up to 92% power conversion efficiency minimises energy waste and heat build-up, making the most of every watt from your solar panel or vehicle battery.
Dual USB Output: Two USB-A ports deliver a combined maximum of 5V/3A, letting you charge two devices at the same time — ideal for phones, tablets, and power banks.
Wide Input Range (6V–40V DC): Compatible with 12V/24V vehicle systems, solar charge controllers, and a broad range of DC power sources. Input connector: 5.5×2.1 mm barrel jack plus included wire leads.
Compact & Lightweight: At just 50 × 35 × 12 mm and a red PCB design, this module fits neatly into enclosures, DIY builds, or project boxes without taking up valuable space.
Broad Device Compatibility: Supports any USB 5V device — smartphones, tablets, portable speakers, GPS units, and more.
Wide Operating Temperature: Rated from –40 °C to +85 °C, performing reliably in harsh outdoor or automotive environments.

Full Specifications

Input Voltage	6V–40V DC (5.5×2.1 mm port)
Output Voltage	5V (fixed)
Output Current	3A maximum
Efficiency	Up to 92%
Switching Frequency	150 kHz
Operating Temperature	–40 °C to +85 °C
Dimensions	50 × 35 × 12 mm (L × W × H)
Color	Red PCB
Country of Origin	Made in Mainland China

What's in the Box

1 × Dual USB Step-Down Converter Module
1 × Wire (pre-attached leads)

Ideal Use Cases

Solar charging systems and solar controller projects
12V/24V vehicle USB charging in cars, trucks, RVs, and boats
DIY electronics, maker projects, and embedded power supplies
Off-grid and outdoor charging setups

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For more information on electrical safety standards for DC power conversion modules, visit the U.S. Consumer Product Safety Commission (CPSC).

Learn more: Power inverter

Frequently Asked Questions

Q: What input voltage range does this dual USB step-down converter module support?

A: The module accepts a wide DC input from 6V to 40V, making it compatible with 12V car batteries, 24V truck systems, solar panels, and other common DC power sources. The input is via a 5.5×2.1 mm barrel connector plus wire leads.

Q: Can I charge two devices at the same time with this module?

A: Yes! The module features two USB-A output ports with a combined maximum output of 5V/3A. You can charge two smartphones, tablets, or other USB 5V devices simultaneously.

Q: Is this module suitable for solar panel installations?

A: Absolutely. With a wide 6V–40V input range and up to 92% efficiency, this converter is an excellent choice for integrating USB charging into solar controller setups, off-grid systems, or portable solar chargers.

Q: What is the physical size of the module?

A: The module measures 50 × 35 × 12 mm (length × width × height), making it very compact and easy to integrate into custom enclosures, DIY project boxes, or vehicle dashboards.

Made with care

Great value

Elegant design

Quality materials

This product is crafted with quality materials to ensure durability and performance. Designed with your convenience in mind, it seamlessly fits into your everyday life.

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