News: Microelectronics
10 July 2025
EPC launches first GaN-based motor drive reference design for humanoid robot joints and UAVs
Efficient Power Conversion Corp (EPC) of El Segundo, CA, USA — which makes enhancement-mode gallium nitride on silicon (eGaN) power field-effect transistors (FETs) and integrated circuits for power management applications — has introduced the EPC91118, the first commercially available reference design to integrate gallium nitride (GaN) IC technology for humanoid robot motor joints. Optimized for space-constrained and weight-sensitive applications such as humanoid limbs and compact drone propulsion, the EPC91118 delivers up to 15ARMS per phase drive capability for 3-phase BLDC motors from a 15V to 55V DC input in an ultra-compact circular form factor.
At the heart of the EPC91118 is the EPC23104 ePower Stage IC, a monolithic GaN IC that enables higher switching frequencies and reduced losses. The GaN-based power stage is combined with current sensing, a high-resolution magnetic encoder for rotor shaft position, a microcontroller, RS485 protocol support for real-time communication, and 5V and 3.3V power supplies. These controller, sensing, and power conversion functions are all fully integrated on a single board that fits entirely within a 32mm-diameter footprint for the inverter and a 55mm-diameter external frame.
The design was shaped to fit seamlessly inside humanoid joint motors, enabling low-profile, high-efficiency motion control. The high switching frequency enabled by GaN allows the use of compact multi-layer ceramic capacitors (MLCCs) rather than bulkier electrolytic capacitors, contributing to a lower profile and higher-reliability design.
“The EPC91118 is a breakthrough for humanoid robotics, shrinking inverter size by 66% versus silicon while eliminating electrolytic capacitors — thanks to GaN ICs and high-frequency operation,” says CEO & co-founder Alex Lidow.
With a 66% smaller footprint compared to traditional silicon MOSFET implementations, the EPC91118 is claimed to set a new standard in motor drive integration for emerging robotics and drone markets.
The EPC91118 reference design boards are priced at $394.02. The EPC23104 is priced at $2.69/ea in 3Ku reels. Reference design boards and devices are available for immediate delivery from distributor Digi-Key Corp.
EPC launches 3-phase BLDC motor drive inverter reference design
EPC introduces fully configured motor drive inverter reference design
