Part NumberGS66508T
Step File
Allegro Library
Altium Library
Evaluation BoardsGS665MB-EVB
(Mother board)

(Daughter board)

Reference DesignGS66508T-EVBHB
(650 V, 2 kW GaN E-HEMT half bridge)
RDS(on)50 mΩ
QG5.8 nC
Dimensions (mm)7.0 x 4.5 x 0.54
TR QTY3000
MR Size16 mm x 7″
TR Size16 mm x 13″


650V Enhancement Mode GaN Transistor

The GS66508T is an enhancement mode GaN-on-silicon power transistor. The properties of GaN allow for high current, high voltage breakdown and high switching frequency. GaN Systems implements patented Island Technology® cell layout for high-current die performance & yield. GaNPX® packaging enables low inductance & low thermal resistance in a small package. The GS66508T is a top-side cooled transistor that offers very low junction-to-case thermal resistance for demanding high power applications. These features combine to provide very high efficiency power switching.

  • Ultra-low FOM Island Technology® die
  • Low inductance GaNPX® package
  • Easy gate drive requirements (0 V to 6 V)
  • Transient tolerant gate drive (-20 / +10V )
  • Very high switching frequency (> 100 MHz)
  • Fast and controllable fall and rise times
  • Reverse current capability
  • Zero reverse recovery loss
  • Small 7.0 x 4.5 mm2 PCB footprint
  • Dual gate pads for optimal board layout
  • RoHS 6 compliant


  • High efficiency power conversion
  • High density power conversion
  • AC-DC Converters
  • Bridgeless Totem Pole PFC
  • ZVS Phase Shifted Full Bridge
  • Half Bridge topologies
  • Synchronous Buck or Boost
  • Uninterruptable Power Supplies
  • Industrial Motor Drives
  • Single and 3Φ inverter legs
  • Solar and Wind Power
  • Fast Battery Charging
  • Class D Audio amplifiers
  • 400 V input DC-DC converters
  • On Board Battery Chargers
  • Traction Drive


650 V Universal Motherboard

This universal motherboard can be used with daughter cards (sold separately) to evaluate the entire GaN Systems 650 V family of GaN E-HEMT products.


  • GS66504B-EVBDB
  • GS66508B-EVBDB
  • GS66508T-EVBDB
  • GS66516T-EVBDB


650 V GaN E-HEMT daughter board

This product requires a motherboard (GS665MB-EVB)

The GS66508T-EVBDB daughter board consists of two GaN Systems 650V GaN Enhancement-mode HEMTs (part number GS66508T) and all necessary circuits including half bridge gate drivers, isolated power supplies and optional heatsink to form a functional half bridge power stage. It allows users to easily evaluate the GaN E-HEMT performance in any half bridge-based topology, either with the universal motherboard or the users’ own system design.

  • Serves as a reference design and evaluation tool as well as deployment-ready solution for easy insystem evaluation
  • Vertical mount style with height of 35mm, which fits in majority of 1U design and allows evaluation of GaN E-HEMT in traditional through-hole type power supply board
  • Current shunt position for switching characterization testing
  • Universal form factor and footprint for all products


650 V, 2 kW GaN E-HEMT half bridge

REFERENCE ONLY – Out of stock

The GS66508T-EVBHB evaluation board (EVB) is designed to demonstrate the performance of GaN Systems’ 650V GaN enhancement mode high electron mobility transistor (E-HEMT) devices. The EVB is a fully functional half bridge power stage consisting of two 650V GaN E-HEMTs (top side cooled GS66508T, 30A/55mΩ), gate drive power supply, half bridge gate drivers and heatsink.

To evaluate the performance of GaN E-HEMT devices in real power circuits, the EVB can be easily configured into any half bridge based topology. The board serves as a reference design for:

  • Gate driver circuit
  • Half bridge PCB layout
  • Thermal management

The block diagram of the GS66508T-EVBHB can be seen above. All components are mounted on the top side except for E-HEMTs, Q1 and Q2, which are mounted on the bottom side of the EVB. A heatsink is mounted from the bottom side as well, in order to provide cooling for the two GaN E-HEMTs. The board includes all necessary components for building a half bridge power stage and provides footprints for output power inductors and capacitors to allow users to configure the board into different operational modes.