25 August 2021
VisIC introduces 7.2kW bidirectional totem-pole PFC reference design
VisIC Technologies Ltd of Ness Ziona, Israel – a fabless supplier of power conversion devices based on gallium nitride (GaN) transistors for automotive high-voltage applications – has announced its new reference design for totem-pole power factor correction (PFC) aimed at on-board chargers (OBC) for electric vehicles (EVs). The firm says that the reference design is another step in the ongoing effort to support customers and improve the power conversion systems to fit the demanding size, cost and efficiency targets for the automotive market.
Picture: VisIC’s top-cooled V22TC65S1A GaN devices.
On-board chargers now embrace the bidirectional requirements of the vehicle-to-grid (V2G) and grid-to-vehicle (G2V) functions by using new topologies such as the totem-pole PFC. The new reference design from VisIC is targeted at the higher-power segment of 7.2kW with increased efficiency, size and cost structure.
Based on the VisIC V22TC65S1A 22mΩ, 650V, 100A GaN device that is optimized for the PFC stage, the design requires a single device per leg and achieves a power density above 130W/inch3, or 8kW/L, operating at 140kHz without paralleling GaN devices and giving an efficiency above 98%.
The reference design kit includes everything needed to operate the unit in both PFC and inverter modes, from the on-board firmware on MCU to the coldplate for high-power operation, as well as all the design files.