News

Infineon Previews 400V and 600V GaN Switches & Galvanically-Isolated Drivers

June 07, 2018 by Paul Shepard

Infineon Technologies AG will start volume production for CoolGaN™ products by the end of 2018, the company announced during PCIM Europe. Engineering samples of the high reliable GaN solution in the market are available now. At PCIM 2018 Infineon showcased CoolGaN products in telecom, adapter, wireless charging and server solutions.

Using a p-GaN gate structure, Infineon CoolGaN™ works similar to conventional silicon MOSFETs with enhancement mode gate drive bias. When a positive gate voltage is applied, electrons are accumulated and form a low resistance channel in a lateral two-dimensional electron gas (2DEG) layer between drain and source.

Unlike silicon MOSFETs with PN junction body diodes, GaN devices conduct reverse current as one of the switching states, eliminating reverse recovery charge which is a major source of switching noise.

"Infineon is the global leader in power solutions and we truly believe that the next big thing in power management is gallium nitride," said Steffen Metzger, Senior Director High Voltage Conversion at Infineon.

"Our goal is to be the first choice for customers when it comes to GaN power, and we have all assets in place to live up to this ambition. The market for GaN has been gaining a strong momentum; the advantages of using this technology in certain applications are evident.

"From operating expense and capital expenditure reduction, through higher power density enabling smaller and lighter designs, to overall system cost reduction, the benefits are compelling," Metzger concluded.

Using a p-GaN gate structure, Infineon CoolGaN™ works similar to conventional silicon MOSFETs with enhancement mode gate drive bias. When a positive gate voltage is applied, electrons are accumulated and form a low resistance channel in a lateral twodimensional electron gas (2DEG) layer between drain and source.

Infineon's CoolGaN is the one of most reliable and globally qualified GaN solutions in the market. During the quality management process not only the device is tested, but also its behavior in the application.

The performance of CoolGaN is beyond other GaN products in the market. At 100 ppm (parts per million), its predicted lifetime is about 55 years, exceeding the expected lifespan by 40 years. CoolGaN enables for example doubled output power in a given energy storage slot size, freeing up space and realizing higher efficiency at the same time.

CoolGaN 600V HSOF-8-3

Availability

Full production of CoolGaN 400V and 600V e-mode HEMTs will start by end of 2018.

CoolGaN 400V will be available in 70mΩ in SMD bottom-side cooled TO-leadless and top-side cooled DSO-20-87 package.

CoolGaN 600V comes in top-side cooled DSO-20-87 package and bottom-side cooled DSO-20-85.

With 70mΩ and 190mΩ 600V CoolGaN devices in bottom-side cooled TO-leadless and DFN 8x8 packages, the 600V CoolGaN portfolio will be complemented.

1-channel isolated gate drivers for enhancement mode GaN HEMTs

Also during PCIM, Infineon was showing two new members of a one-channel galvanically-isolated gate driver IC family, the EiceDRIVER™ 1EDF5673K and 1EDS5663H. The new components are designed specifically to work with enhancement mode GaN HEMTs with non-isolated gate (diode input characteristic) and low threshold voltage, such as CoolGaN™.

Half-bridge application design overview (click on image to enlarge)

Applications for the new drivers are expected to include Bridgeless totem-pole PFC stages and LLC stages in telecommunications and server power supplies, Active-clamping flybacks in AC adapters, 3-phase motor drives, Class E wireless charging, and Class D audio amplifiers.

High-efficiency GaN switched mode power supply (click on image to enlarge)

The EiceDRIVER™ 1EDF5673K and 1EDS5663H provide complete support of all requirements specific to enhancement GaN HEMTs operation:

  • Low driving impedance (on-resistance 0.85 Ω source, 0.35 Ω sink)
  • Resistor programmable gate current for steady on-state (typ. 10 mA)
  • Programmable negative gate voltage to completely avoid spurious turn-on in half-bridges

Switching behavior independent from duty cycle:

  • Two off -voltage levels
  • Negative gate drive voltage available even for first pulse

Integrated galvanic isolation:

  • High power density of the application design
  • Excellent system-level timing accuracy
  • Robust common mode transient immunity (CMTI)
  • Functional and reinforced levels available

Key features include:

  • Output impedance:
    • RDS(on) source - 0.85 Ω,
    • RDS(on) sink - 0.35 Ω
  • Input-output propagation delay accuracy: +/- 5 ns
  • CMTI: > 150 V/ns
  • Isolation:
    • 1EDF5673K: VIOWM > 460 Vrms
    • 1EDS5653H: VIOTM > 6000 Vpeak
  • Package:
    • 1EDF5673K: 5x5 mm LGA 13-pin
    • 1EDS5663H: 300 mil DSO 16-pin