65 W GaN Power Supplies Shrink Footprint, Not Performance

Power supplies aren’t the most glamorous components, but they keep every circuit alive. As devices shrink and workloads get heavier, designers are running out of space for the power they need. In its latest power supply families, Bel Power Solutions utilizes known gallium nitride (GaN) technology to deliver higher efficiency and large outputs in hardware small enough to disappear into modern boards.

Bel has released two 65 W open-frame AC-DC power supply families, the MDP65 for medical applications and the HDP65 for industrial and ITE systems. Both use GaN transistors instead of traditional silicon, allowing for higher efficiency, lower heat generation, and a smaller footprint than previous 2 x 3-inch units. Measuring just 1 x 3 inches, the compact design frees up valuable board real estate for other critical components.

The HDP65 and MDP65 65W GaN power supplies. Image used courtesy of Bel Fuse Inc.

Compact Power With GaN Efficiency

GaN technology continues to reshape how engineers think about power design. Compared to silicon, GaN switches faster and handles higher voltages with less energy loss. For these 65 W supplies, that means up to 92% efficiency and cooler operation, even in tightly sealed enclosures. Both the HDP65 and MDP65 are convection-cooled, so they don’t require fans or external airflow, reducing noise and maintenance requirements.

Power derating over the operating temperature ratings of the MDP65 and HDP65. Image used courtesy of Bel

The MDP65 and HDP65 can operate within a temperature range from -20 to 70°C, allowing the supplies to function reliably in various conditions, including enclosed hospital equipment or industrial control cabinets. Each unit also features an adjustable DC output that ranges from 5 to 56 V, providing flexibility for various system requirements. This voltage range allows the power supplies to be used in everything from medical monitoring and lab instruments to industrial sensors, IoT modules, or even small data center hardware.

Designed for Safety and Reliability

While the MDP65 and HDP65 share many features, their safety certifications are distinct. The MDP65 was purpose-built for medical environments, meeting the stringent IEC/EN 60601-1 standard with 2xMOPP isolation, and is suitable for Type BF applications where patient contact may occur. The HDP65 is certified to IEC/EN 62368-1, ensuring safe operation in industrial, networking, and test environments.

Both models are UL and Nemko-approved and RoHS-compliant. The units feature a universal input voltage range of 90 to 264 volts AC for the MDP65 and 90 to 305 volts AC for the HDP65, making them compatible with global power standards. Bel also emphasized long-term reliability and total cost efficiency in the design. Each model includes protection against overload, overvoltage, and overheating, ensuring continuous operation without premature failure, especially when combined with high efficiency and a power density of 17.2 watts per cubic inch.

The HP065-1224. Image used courtesy of Bel

Smaller Size, Broader Reach

Using GaN transistors enhances switching efficiency and enables higher operating frequencies without excessive thermal buildup. Lower switching loss also means less heat dissipation, which reduces the need for large heat sinks or forced-air cooling. This allows designers to keep enclosure sizes small while still meeting thermal requirements for continuous operation.

Bel’s engineers designed the series for long operating life under continuous loads, making it ideal for 24/7 systems such as medical test equipment, network and data centers, test and measurement equipment, and consumer IoT devices. The units’ convection cooling and low profile make them particularly well-suited for compact enclosures where space and airflow are limited.

In an industry where space is tight and reliability is non-negotiable, Bel’s GaN-based power supplies deliver a clean blend of performance, efficiency, and footprint reduction. For engineers balancing cost, compliance, and compact design, these modules make the tradeoffs much easier to live with.