Power factor control via GaN
One of the items shown by transphorm was this firmware-based 3.3-kW bridgeless totem-pole FPC 
reference design built with the firm’s TP65H050WS 650-V GaN FETs. A DSP handles the control and the output is firmware-programmable in the range of 373 to 393Vdc. The PFC is a switched design operating in the 45 kHz to 150 kHz range. Typical applications are in vehicular on-board chargers and high-end industrial supplies. Another design shown at PCIM was a dc-dc converter, bottom, also employing GaN FETs. The company says the GaN-based converter excels as switching freqencies rise.
NEXT PAGE: GaN FETs now fit into traction inverters
