Summary
- Infineon and Enphase have developed and tested 900V monolithic GaN bidirectional switches.
- The devices are being integrated into Enphase's IQ Solid-State Transformer development programme.
- Production qualification remains ahead, and no completed commercial data centre deployment has been confirmed.
Infineon Technologies will supply 900V gallium nitride bidirectional switches to Enphase Energy for solid-state transformer modules being developed for AI data centre electrical infrastructure.
The companies have completed initial testing of the monolithic devices, which are now being integrated into Enphase’s IQ Solid-State Transformer development programme. Production qualification remains outstanding, and neither business has confirmed a completed commercial data centre deployment using the new switches.
The technology extends gallium nitride switching into a higher operating voltage class while retaining high-frequency characteristics that can support compact power conversion systems.
Data centres distribute electricity through equipment that transforms, converts, protects, and regulates power before it reaches computing hardware. The configuration of that electrical system influences conversion losses, equipment dimensions, installation costs, and the ability to maintain operation during disturbances.
Solid-state transformers use power electronic devices and high-frequency conversion techniques to perform functions associated with conventional electrical conversion equipment. Their proposed advantages include greater control over electrical conditions and opportunities to reduce the physical size of particular power conversion stages.
Infineon’s 900V CoolGaN devices integrate bidirectional voltage blocking and current conduction within a single switch. The arrangement can simplify some circuit designs by reducing the number of separate switching components required.
Higher switching frequencies may also allow designers to use smaller magnetic components. Transformers and inductors occupy space within power conversion equipment, so reducing their dimensions can contribute to higher electrical power density.
Those potential benefits must be considered alongside the thermal and electrical behaviour of the completed system. Increasing switching frequency can introduce additional design requirements involving losses, electromagnetic interference, insulation, and the handling of electrical faults.
Enphase led the system-level demonstration, building on its previous work with gallium nitride power electronics. The two companies have already collaborated on 650V devices used in Enphase’s IQ9 microinverter programme.
The 900V devices are intended for different applications, including the solid-state transformer modules being developed for AI computing facilities. The companies also identify commercial solar inverters as a potential market.
The new voltage class is relevant to the industry’s investigation of 800V direct current distribution and higher-voltage electrical architectures. Increasing distribution voltage can reduce current for a given power demand, potentially lowering resistive losses and the conductor requirements associated with very large electrical loads.
Power distribution at these voltages introduces demanding requirements for insulation, fault protection, isolation, and maintenance. Engineers must consider how equipment behaves during normal operation and how rapidly faults can be detected and interrupted.
Some proposed architectures aim to reduce the number of conversion stages between incoming electrical supply and computing electronics. Whether that approach produces an efficiency improvement depends on losses across the complete electrical chain rather than the performance of one semiconductor device.
Thermal performance must also be evaluated at system level. Even relatively efficient converters produce heat, and equipment designed for high electrical density must provide sufficient cooling under sustained load and during abnormal operating conditions.
Infineon says its bidirectional switch technology supports the development of future power systems operating towards 1,500V DC. That does not establish that the specific 900V component can independently withstand a 1,500V potential; the complete circuit architecture determines how semiconductor devices are applied.
The immediate development milestone is successful device testing and integration into Enphase’s engineering programme. Production qualification, system validation, and evidence from commercial operation remain necessary before performance claims can be evaluated under data centre conditions.
