When considering off board AC/DC power supplies for new applications, although gallium nitride (GaN) based alternatives have better electrical performance and energy efficiency, designers often still choose silicon (Si) based components. This may be due to long-standing assumptions about cost-effectiveness or default choices. However, designers may have overlooked the reduced cooling requirements for gallium nitride based substitute products.

Silicon semiconductors have been the mainstream of the electronics industry since the second half of the 20th century. Gallium nitride was synthesized in the 1930s, but it took a long time to gain favor and was first widely used in light-emitting diodes in the early 1990s. After the commercial feasibility of manufacturing gallium nitride transistors as a substitute for metal oxide semiconductor field-effect transistors (MOSFETs), gallium nitride was more widely used.

Nevertheless, silicon remains the mainstream of AC/DC power supplies. By utilizing more mature manufacturing processes, suppliers can provide more silicon transistors within the cost constraints of product designers. However, silicon-based components have encountered performance and heating bottlenecks, which presents opportunities for a wider consideration of alternative products based on gallium nitride.

Power supplies using gallium nitride have higher electron mobility and wider bandgap, allowing them to operate at higher frequencies, with higher energy efficiency and a more compact appearance.

Advantages of Gallium Nitride in Power Products
Compared to silicon transistors, gallium nitride transistors have lower resistance and switching losses, faster switching speed, and lower power consumption. In addition, gallium nitride transistors have better thermal conductivity and can operate at higher temperatures. This reduces the demand for bulky and noisy cooling components such as radiators, frames, or fans.

Reducing components can improve reliability, make the power supply more compact, and save valuable space when designing new applications. Smaller and more reliable power supplies are suitable for various applications that require high-performance, low-noise power supplies.

Off board GaN AC/DC power supply can be used for the following applications:

Medical equipment that requires efficient, reliable, and quiet power supply
Durable and adaptable industrial equipment for robots, sensors, or controllers
Consumer electronics products that power fast, lightweight, and portable devices
Game system, console, and virtual reality helmet using immersive low-temperature power supply
Gallium Nitride Power Supplies from Various Brands under Bel
Bel Power Solutions is a subsidiary of Bel Fuse Inc. and has been expanding its range of gallium nitride based AC/DC power products in the market. Both EOS Power and CUI Inc. brands belong to Bel. These brands offer a portfolio of power products using gallium nitride technology, aimed at achieving higher power density and energy efficiency than equivalent silicon-based MOSFETs.

EOS is renowned in the industry for its ultra small power supply.

Figure 1: Appearance of EPG300 and MEPG300 power supplies. (Source: EOS Power)

Both the EPG300 and MEPG300 AC/DC power supplies provide six single output voltages ranging from 12V to 58V, with an energy efficiency of up to 94%. For example, EPG300-1312 is an open power supply with a 12V output, measuring 4.00 "x 2.00" x 1.47 "(101.6 mm x 50.8 mm x 37.3 mm).

MEPG300-1312 and other models in this series are designed specifically for medical applications, including hospital beds, imaging equipment, monitoring equipment, surgical equipment, and diagnostic equipment. This type of power supply complies with the latest medical standards (EN/IEC 60601-1) and offers 2 x MOPP isolation options suitable for Class I applications.

The EPG500 and MEPG500 AC-DC power supplies (Figure 2) can provide up to 500 W of regulated output power over a wide input range of 90 VAC to 264 VAC. Both power supplies offer six single output voltages ranging from 12 V to 58 V, with dimensions of 5.00 "x 3.00" x 1.58 "(127.0 mm x 76.2 mm x 40.0 mm).