EPC releases two new white papers on GaN power conversion
Efficient Power Conversion (EPC) has published two new technical white papers addressing critical power-conversion challenges in two rapidly evolving markets: AI data centres and high-performance multi-axis motor drives.
The first white paper, 'GaN-Based Power Delivery in AI data centres: High-Density Power Conversion Architectures from 800 VDC to Point-of-Load' examines the transition toward 800 VDC distribution as AI racks move from tens of kilowatts toward hundreds of kilowatts and megawatt-scale compute clusters. At 800 VDC, a 200 kW rack requires only one-sixteenth of the current of a 48 V distribution bus, reducing conductor size, I²R losses, and cooling requirements.
The paper explores three architectures for converting 800 VDC to 50 V, 12.5 V, and 6.25 V rails, with particular focus on modular Input-Series, Output-Parallel (ISOP) LLC converters. By dividing the high-voltage input among multiple modules, the architecture enables low-voltage GaN FETs with a better Figure of Merit, when compared to higher-voltage devices, to perform high-ratio conversion at high switching frequencies.
Practical results demonstrate the performance potential: an 800 V-to-50 V implementation reaches 98.6 percent peak efficiency, while the EPC91123 800 V-to-12.5 V converter achieves 98.2 percent peak efficiency in an 8 mm profile. A 6 kW 800 V-to-6.25 V architecture reaches 98 percent peak and 97 percent full-load efficiency.
“As GPU power continues to increase, power conversion must move closer to the processor while minimising conversion stages,” said Jason Zhang, Vice President of DC-DC Marketing and System Engineering at EPC. “Gen 7 GaN combined with modular ISOP architectures provides a practical path from an 800 VDC backbone to the very low bus voltages and extremely high currents required by next-generation AI processors.”
The second white paper, 'From Device to Platform: EPC23108/09/10/11 100 V Integrated GaN Power Stages Simplify Multi-Axis Motor Drive Design', addresses the increasing complexity of motor drives used in humanoid robots, drones, surgical robotics, and precision-motion systems.
EPC’s EPC231xx family integrates high- and low-side eGaN FETs, gate drive, level shifting, control interface, and protection functions into a monolithic GaN 100 V ePower™ Stage IC. The accompanying EPC91128–EPC91131 three-phase BLDC/PMSM inverter platforms give engineers a complete environment to evaluate current capability, sensing, protection, thermal performance, and different PWM interfaces.
The platforms operate across a recommended 14–80 V range (48 V typical) and support switching frequencies from 20 to 150 kHz. Complementary PWM versions maximise control flexibility, while single-PWM-input-pin versions reduce control-line count and wiring complexity—an increasingly important advantage as robotic systems scale to dozens of motors.
“In multi-axis robotics, power density is only part of the challenge,” said Marco Palma, VP Motor Drive Marketing and System Engineering at EPC. “Integration must also simplify control, protection, sensing, thermal management, and wiring. The EPC231xx family and its evaluation platforms give engineers a validated starting point that can be replicated efficiently across many motor axes.”
