Designed for modern PV modules exceeding 400W, the design demonstrates a high-frequency, single-stage DC-AC conversion approach that reduces component count, lowers BOM cost, and maintains grid-compliant power quality.
The 500W Microinverter Reference Design (ERD00718), jointly developed by Eggtronic and Renesas Electronics, provides a high-efficiency platform for engineers developing next-generation photovoltaic (PV) microinverters and power conversion systems. The design combines Eggtronic’s EPIC mixed-signal control technology with Renesas’ bidirectional Gallium Nitride (GaN) power device to demonstrate a compact, high-performance single-stage DC-to-AC conversion architecture optimised for modern solar energy applications.
The platform is designed to address the increasing power demands of contemporary PV modules, which now commonly exceed 400W output. Traditional microinverter topologies often require trade-offs between efficiency, power density, thermal management, system complexity, and cost. This design demonstrates an alternative approach that leverages advanced semiconductor technologies to achieve high conversion efficiency while reducing component count and overall system complexity.
At the heart of the design is the Eggtronic EPIC2ACO01 mixed-signal controller, which implements proprietary Variable Frequency Modulation (VFM) and current-mode control algorithms. These control techniques maintain Zero-Voltage Switching (ZVS) across the entire operating load range, significantly reducing switching losses and improving overall energy conversion efficiency. The controller enables operation at switching frequencies up to 1 MHz, allowing substantial reduction in magnetic component size and contributing to higher power density. The single-stage topology also minimises reactive power circulation, lowers bill-of-materials (BOM) cost, and maintains low Total Harmonic Distortion (THD).
The power stage utilises the Renesas TP65B110HRU bidirectional GaN switch configured in a common-drain arrangement suitable for cycloconverter-based AC switching applications. The device features low on-resistance and fast switching characteristics, enabling efficient high-frequency operation with reduced conduction losses. These characteristics support compact thermal designs and facilitate increased power density while maintaining reliable operation.
Performance measurements demonstrate an average efficiency of 96.1% under California Energy Commission (CEC) test conditions and 95.9% under European Union (EU) efficiency standards. The platform maintains a relatively flat efficiency profile across a wide operating range, making it suitable for real-world solar energy generation environments. Total Harmonic Distortion is maintained below 3%, meeting IEEE 1547 grid-interconnection requirements.
Key design specifications include 500W continuous output power capability, support for switching frequencies up to 1 MHz, sub-3% THD performance, and a cost-optimised single-stage architecture. These characteristics make the platform suitable for evaluating high-efficiency residential and commercial microinverter solutions. The reference design serves as a development platform for OEMs and system manufacturers seeking to accelerate product development while optimising efficiency, thermal performance, power density, and system cost. The design incorporates the EPIC2ACO01 controller and TP65B110HRU bidirectional GaN device as the core enabling technologies for next-generation solar microinverter implementations.
For additional information, please visit https://www.eggtronic.com/power-converters/solaregg/ or https://www.renesas.com/en/products/tp65b110hru.
