26 August 2021
ST introduces 45W and 150W MasterGaN devices for high-efficiency power conversion
Aiming to ease the transition to high-efficiency wide-bandgap semiconductor technology, device maker STMicroelectronics of Geneva, Switzerland has released the MasterGaN3 and MasterGaN5 integrated power packages for applications up to 45W and 150W, respectively.
Joining the MasterGaN1, MasterGaN2, and MasterGaN4, which target applications from 65W to 400W, the additions give extra flexibility to choose the optimum gallium nitride (GaN) device and driver solution when designing switched-mode power supplies (SMPS), chargers, adapters, high-voltage power factor correction (PFC), and DC/DC converters.
ST says that its MasterGaN concept simplifies migrating from ordinary silicon MOSFETs to GaN wide-bandgap power technology. The devices integrate two 650V power transistors with optimized high-voltage gate drivers and associated safety and protection circuitry, eliminating gate-driver and circuit-layout design challenges. Combined with the higher switching frequencies possible with GaN transistors, these integrated devices enable power supplies that are up to 80% smaller than silicon-based designs as well as being extremely robust and reliable.
The GaN power transistors of MasterGaN3 devices have asymmetrical on-resistance (Rds(on)) of 225mΩ and 450mΩ, making them suited to soft-switching and active-rectification converters. In MasterGaN5 both transistors have 450mΩ Rds(on) for use in topologies such as LLC-resonant and active clamp flyback.
In common with other MasterGaN family members, both devices have inputs compatible with logic signals from 3.3V to 15V, which simplifies connection of a host DSP, FPGA or microcontroller, and external devices such as Hall sensors. They also integrate protection including low-side and high-side undervoltage lockout (UVLO), gate-driver interlocks, over-temperature protection, and a shutdown pin.
Each MasterGaN device is supported with a dedicated prototype board to help designers jump-start new power supply projects. The EVALMASTERGAN3 and EVALMASTERGAN5 boards contain circuitry to generate single-ended or complementary driving signals. There is an adjustable dead-time generator, as well as connections for the user to apply a separate input signal or PWM signal, add an external bootstrap diode to help with capacitive loads, and insert a low-side shunt resistor for peak-current-mode topologies.
Housed in a 9mm x 9mm GQFN package optimized for high-voltage applications with 2mm creepage distance between high-voltage and low-voltage pads, MasterGaN3 and MasterGaN5 are in production now, priced from $6.08 for MasterGaN3 and $5.77 for MasterGaN5, for orders of 1000 pieces.