News: Microelectronics
24 September 2021
GaN Systems launches 3kW bridgeless totem pole PFC + LLC resonant converter power supply unit
GaN Systems Inc of Ottawa, Ontario, Canada (a fabless developer of gallium nitride (GaN)-based power switching semiconductors for power conversion and control applications) has introduced a high-efficiency, high-power-density 3kW bridgeless totem pole (BTP) PFC + LLC resonant converter power supply unit (PSU) that exceeds the 80+ Titanium standard. The combined GaN BTP-PFC (power factor correction) with GaN LLC resonant converter enables designers to create lower-cost power supplies that meet demands to deliver more power in a smaller footprint and new energy-efficiency requirements, including the European Union’s ‘Lot 9’ 2023.
“With the expanding volume of data, game-changing solutions are needed to reduce energy consumption and contribute to a more sustainable future in our data centers, and these PFC and LLC reference designs take PSUs to the next level,” says Paul Wiener, VP of strategic marketing.
Increasing efficiency and power density while reducing size and cost obstacles
New efficiency mandates, increasing power and data demands, and the shift to ‘dollars per density’ (where density is a measure of size and power of the power supply) spur the immediate need to change data-center economics with smaller, more efficient, and reliable power supply designs.
GaN brings higher efficiency, higher power density, lower cost, and increased sustainability to the data-center ecosystem. GaN Systems concluded that significant energy and cost savings are achieved by switching from silicon-based PSUs to GaN-based PSUs. Since data centers vary in size, the savings are based on a 10-rack unit of measure. From a sustainability perspective, each set of 10 racks reduces CO2 emissions by 100 metric tons per year and, financially, GaN-based PSUs increase data-center profits by $3m per year.
3kW AC/DC PSU design
Most high-efficiency power supplies are designed with a bridgeless or semi-bridgeless PFC stage and a resonant DC-DC stage such as an LLC resonant converter. GaN Systems says that, together, the 3kW BTP-PFC and 3kW LLC converter designs exceed 80+ Titanium efficiency requirements, achieve high power density above 80W/inch3, and reduce PSU total cost.
- 3kW BTP is the latest technology for a high-efficiency PFC. GaN Systems says that its reference design offers less conduction loss and enables near 99% peak efficiency due to no body diode loss and the higher performance of GaN transistors. Additional benefits include using 40% fewer components and a 10-25% reduction in system cost.
- GaN Systems says that its 3kW LLC reference design offers higher frequency (>200kHz for higher power density) and higher efficiency at both light and full load. The 54V output voltage can support 48V power architectures for data centers. The design highlights a power density of 146W/inch3 (air-forced cooling) and >98% peak efficiency, achieved with a resonant frequency at 250kHz and at a maximum frequency at 400kHz.
- Both 3kW BTP PFC and LLC reference designs use the latest-generation 650V enhancement-mode (E-mode) transistor GS-065-030-2-L (claimed to be the first GaN product on the market that enables designers to get the advantages of low-cost GaN in applications at the 3000W power level).
