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Future Electronics
GaNdalf II
CoolGaN based digital Power Factor Correction development system

The improved Future Electronics blueprint for bridgeless PFC circuit design. 

  • >99% Peak Efficiency
  • Latest GaN power components
  • Low component count
  • Adaptable and flexible development platform


Power Factor Correction (PFC) is widely used in AC-DC power supplies with an input power greater than 75W. The PFC circuit controls the input current to synchronize it with the input voltage and to minimize reactive power losses. Power-system designers are under more pressure than ever to achieve high efficiency across the whole AC-DC converter circuit.

In the PFC stage, the drive for efficiency has led designers to evaluate various bridgeless PFC circuit topologies, which remove the rectifying diode bridge and its associated power losses from the input of the PFC stage. The bridgeless totem pole PFC topology offers various advantages compared to other approaches, including: 

  • Fewer components
  • Lowest conduction losses
  • Highest efficiency 

Conventional silicon super-junction MOSFETs are unsuitable for use in the hard-switched half-bridge arrangement in a bridgeless totempole topology, which calls instead for the superior characteristics – including low output capacitance and zero reverse recovery – of GaN High Electron-Mobility Transistor (HEMT) switches. 

GaN power switch is the crucial technology enabling the ultra-efficient bridgeless totem pole topology. The Future Electronics GaNdalf II development system provides a blueprint for OEMs’ implementation of the bridgeless totem-pole Power Factor Correction (PFC) topology.

Featuring components from leading suppliers of technology supporting this topology including: 

  • Infineon’s Enhancement Mode GaN transistors (CoolGaNTM). These devices provide higher efficiency performance from the superior electrical properties of the wide bandgap gallium nitride material which supports better switching performance and lower switches losses than equivalent silicon-based FETs. Used on GaNdalf II, CoolGaNTM devices from Infineon offer outstanding performance when operating under continuous conduction mode, helping the PFC stage to achieve efficiency of 99.0%.
  • Microchip’s dual-core 16-bit Digital Signal Controller (DSC)

Offering a peak efficiency > 99% and THD < 5%, GaNdalf II is the ideal starting point for highly efficient power conversion designs supplying loads up to 2kW


Key components of the GaNdalf II power system:


• Infineon CoolGaNTM and isolated driver

• Microchip dsPIC33CH dual core 16-bit digital signal controller

• Microchip signal chain and power management devices

• Myrra custom inductor

• Murata isolated DC-DC converter module

• Infineon 17mOhm MOSFET for synchronous rectification


Key features of the GaNdalf II PFC circuit:


• Input-voltage range: 85V to 265V AC

• Output voltage: 400V DC

• Supports loads up to 2kW

• <10% total harmonic distortion

• >0.99 power factor

• Digitally controlled: eases overall control (zero crossing, GaN and synchronous rectification drive)