IEEE Power Electronics Magazine - March 2015 - 45

Table 1. A partial list of suppliers of GaN power devices.

suppliers

Epi substrate

wafer size

transistor type

Avogy

GaN

2-in (50 mm)

E-mode1
vertical JFET

Maximum
Voltage (V)

Diode

Maximum
Voltage (V)

1,200

Schottky
PN

600 (Schottky)
1,700 (PN)

Efficient Power Conversion

6-in (150 mm)

E-mode FET

450

Schottky

600

Exagan

8-in (200 mm)

1,200

Fuji Electric

Schottky

600

Fujitsu Semiconductor

6-in (150 mm)

GaN Systems

6-in (150 mm)

E-mode HEMT

650

International Rectifier2

6-in (150 mm)

Depletion-mode HEMT3

600

microGaN GmbH

6-in (150 mm)

Heterostructure FET

NXP Semiconductor

Panasonic

6-in (150 mm)

POWDEC K.K.

Sapphire

RF Micro Devices

SiC

4-in (100 mm)

Source switched FET

650

Sanken Electric Co., Ltd.

N/A

Normally off FET

600

Schottky

600

Normally off gate
injection transistor (GIT)
Polarization
Super-junction FET

600

Schottky

650

600

Schottky

600

STMicroelectronics

6-in (150 mm)

E-mode HEMT

200

Transphorm

6-in (150 mm)

HEMT3

600

Schottky

600

Source: How2Power Today.
1
Enhancement-mode. 2Acquired by Infineon Technologies. 3Offered in normally off cascode form.

Devices Meeting that its cascode-configured GaN-on-Si HEMT
can withstand a breakdown voltage of 21,700 V with stable
dynamic on-resistance.
Two applications benefiting from Transphorm's 600-V
GaN-on-Si HEMTs are all-in-one computer power supply and
bridgeless totem-pole PFC. The hard-switching half-bridge
modules are targeted at low-power (1-kW) residential PV
inverters. In a paper presented at PCIM 2014, Transphorm
researchers demonstrated 99% efficiency for a GaN-based
single-phase true-bridgeless totem-pole PFC using synchronous metal-oxide-semiconductor field-effect transistors
(MOSFETs) for line rectification. The GaN-based all-in-one
computer power converter reference design jointly developed
with ON Semiconductor has been adopted by a power supply
manufacturer, but the company will not reveal the name.
Concurrently, the first codeveloped 250-W ac-dc converter, based on 600-V GaN transistors, for an all-in-one
computer power supply is sampling to select customers.
These solutions will address high-power-density applications in the 200-1,000-W power range for compact power
supplies and adapters addressing the telecom and server
markets. Under the terms of the partnership, the codeveloped packaged transistor products will include a low-voltage Si MOSFET from ON Semiconductor for the cascoded
switch and proven GaN high-voltage HEMTs from Transphorm. Copackaging, assembly, and test of the devices
will be done at ON Semiconductor production facilities.
Likewise, International Rectifier (IR), which has been
acquired by Infineon Technologies, is offering its fully charac-

terized cascode 600-V GaN-on-Si HEMT to select customers.
Based on its cascoded GaN HEMTs, IR has readied a 1-MHz
inductor-inductor-capacitor (LLC) resonant dc-dc power
supply reference design (380-400-V input to 24-V output),
which was displayed at Electronica 2014. This design uses a
variation of IR's IRS27952 controller/driver that is optimized
for operation at 1 MHz. Made available to select customers,
it exhibited an efficiency of over 95% at full load. Regarding
power density, IR's vice president of GaN technology device
engineering and product development, Tim McDonald, said,
"Operation at higher frequency allows use of smaller and
thinner magnetic components, which enables 50% reduced
power supply thickness and reduces passive costs."
Bridgeless boost PFC is another major application for
IR's GaN cascode switches. The company has crafted a
demo board to show very high efficiencies (approaching
99%) possible with GaN devices in addition to lower component count and minimal EMI.
Another maker in the high-voltage GaN race is Canada's
GaN Systems. With operating voltages of 100 V and 650 V,
the company has been offering e-HEMT power transistors
in thermally efficient low-inductance packages, labeled
GaNPX, with current ratings from 8 to 100 A. Meanwhile,
it is also sampling 650-V parts with current capability of
200 A in an optimized low-inductance package, with plans
to take it to production later this year. Concurrently, on
the GaN Systems road map is an integrated solution with
the driver and high-current e-HEMT transistor on a single
chip. Plus, with further substrate improvement, it is also

March 2015

z IEEE PowEr ElEctronIcs MagazInE

Table of Contents for the Digital Edition of IEEE Power Electronics Magazine - March 2015