GaN Systems and Renesas shrink DC/DC
Automotive DC/DC achieves 46 percent system size reduction
Renesas' new automotive 48V/12V bidirectional DC/DC converter is powered by GaN Systems power transistors, resulting in significant power density improvements. The converter uses GaN Systems’ GS61008P, a 100V enhancement mode GaN-on-silicon power transistor, to achieve a 46 percent reduction in system size.
The Renesas solution is aimed at 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’ GaN HEMTs allows a 50 percent smaller PCB area compared to using Si-MOSFETs.
The 46 percent reduction of the PCB area is achieved by using 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.
Another benefit of the solution is 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 percent power efficiency over a wide load range of 400W to 3kW.
The ISL78226 PWM controller also eliminates the need for complicated DC/DC converter control software development. And 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,” said Jim Witham, CEO of GaN Systems. “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. This is a major step to bring the benefits of GaN technology to this customer base.”