MasterGaN reference design eliminates heatsink from resonant converter
A reference design for STMicroelectronics’ MasterGaN power packages demonstrates how the integrated devices increase power density, boost energy efficiency, simplify design and accelerate time to market.
The EVLMG1-250WLLC reference design is a 250W resonant converter with a 100 x 60mm board outline and 35mm maximum component height. It features the MasterGaN1, which contains one half-bridge STDrive gate driver optimally connected to two 650V normally-off GaN transistors with matched timing parameters, 150mOhm on-resistance (Rds on), and 10A maximum current rating. The logic inputs are compatible with signals from 3.3 to 15V.
MasterGaN1 is suitable for high-efficiency soft-switching topologies including resonant converters, active clamp flyback or forward converters and bridgeless totem-pole PFC (power factor correction) in AC/DC power supplies, DC/DC converters, and DC/AC inverters up to 400W.
The primary side uses the efficiency of GaN to run without a heatsink. ST also points out that GaN’s switching performance allows an operating frequency which is higher than ordinary silicon MOSFETs. This allows the use of smaller magnetic components and capacitors for greater power density and reduced bill of materials.
Designed for a nominal 400V supply, the EVLMG1-250WLLC provides a 24V/10A output and achieves maximum efficiency above 94 per cent. MasterGaN’s integrated safety features means that the converter output is protected against short circuit and over-current conditions. There is also brown-out protection and an input-voltage monitor that permits sequencing within an array of DC/DC converters and prevents a motor from starting under low voltage conditions.
ST’s MasterGaN family comprises pin-compatible integrated half-bridge products including symmetrical and asymmetrical configurations, housed in a 9.0 x 9.0mm low-profile GQFN package.
The packages contain circuitry rated up to 650V, with 2mm creepage distance between high voltage and low voltage pads.
The EVLMG1-250WLLC is available now.
