AES Semigas


12 October 2022

GaN Systems’ power transistor used in Renesas’ automotive 48V/12V bidirectional DC/DC converter

GaN Systems Inc of Ottawa, Ontario, Canada (a fabless developer of gallium nitride-based power switching semiconductors for power conversion and control applications) says its GS61008P 100V enhancement-mode GaN-on-silicon power transistor is powering the new automotive 48V/12V bidirectional DC/DC converter of Renesas Electronics Corp of Tokyo, Japan, resulting in significant power density improvements and a 46% reduction in system size.

The Renesas solution targets 48V mild hybrid vehicles and electric motorcycles, which require high-efficiency 48V/12V DC/DC converters. GaN allows for high switching frequency at high efficiency — meaning smaller magnetics and a much smaller size. GaN Systems says that its GaN HEMTs allows a 50% smaller PCB area compared with using silicon MOSFETs.

Benefits of the new converter are said to include:

  • A 46% reduction in PCB area by leveraging the switching capabilities of GaN Systems’ transistors — enabling a high-efficiency power converter with a high switching frequency of 500kHz. This allows the use of very small 1.3µH inductors, which leads to a significant decrease in size and weight.
  • High efficiency over a wide range of loads. A combination of GaN with the automatic phase drop function achieves highly efficient power conversion even at low loads, exceeding 94% power efficiency over a wide load range of 400W to 3kW.
  • The ISL78226 PWM controller eliminates the need for complicated DC/DC converter control software development.
  • The half-bridge driver ISL78420/444 provides an easy and cost-effective method of driving GaN transistors.

“Customers in automotive are constantly looking for improvements in power density and cost, and this design is another reflection that GaN delivers significant improvements in power density in a smaller, more efficient and cost-effective design,” says CEO Jim Witham. “The fact that the design comes from Renesas is significant, as they are a market leader in semiconductor solutions for automotive, with a reputation for understanding the needs of the industry,” he adds. “This is a major step to bring the benefits of GaN technology to this customer base.”

While GaN has significant traction in industries like consumer electronics, it is becoming the technology of choice for power conversion and battery charging in hybrid and electric vehicles, the firm claims. GaN offers much higher performance than silicon and silicon carbide at very low cost — making it possible to cost-effectively reduce the weight and increase the efficiency of a wide range of electric vehicles, it adds.

Tags: GaN Systems Renesas E-mode GaN FETs