Transphorm Unveils Compact 240 W Power Adapter Reference Design

Transphorm Unveils Compact 240 W Power Adapter Reference Design

Transphorm, a pioneer in and global supplier of high reliability, high-performance gallium nitride (GaN) power conversion products announced the availability of its new 240 W Power Adapter Reference Design. The TDAIO-TPH-ON-240W-RD deploys a CCM Boost PFC + Half-Bridge LLC topology to deliver a peak power efficiency of over 96 percent with a power density of up to 30 W/in3. Transphorm’s design uses three SuperGaN FETs (TP65H150G4PS) each with an on-resistance of 150 milliohms. The GaN FET comes as a 3-lead TO-220, a well-known and long-trusted transistor package that offers superior thermals at the low line for higher current power systems running PFC configurations.

The reference design is intended to simplify and quicken power system development for applications such as high-power density AC-to-DC power supplies, fast chargers, IoT devices, laptops, medical power supplies, and power tools.

Key Specifications and Features

The TDAIO-TPH-ON-240W-RD is a 240 W 24 V 10A AC-to-DC power adapter reference design. It pairs the TP65H150G4PS GaN FETs with onsemi’s off-the-shelf NCP1654 CCM PFC controller and NCP1399 LLC controller. The design uses a 25-millimeter heatsink that produces a power density of over 24 W/in3. The power density can increase by approximately 25 percent to 30 W/in3 depending on the heatsink design.

This high power density and efficiency range are primarily due to the FET’s packaging as Transphorm offers the only high-voltage GaN devices in a TO-220. Power adapters, along with all universal AC-to-DC power supplies, require high current at the low line (i.e., 90 Vac) which can require paralleling two PQFN packages (as typically seen with e-mode GaN) to achieve the desired power output. This method reduces a power supply’s power density while requiring 2x part count. Transphorm’s TO-220 packages mitigate this, thus providing unparalleled power density at a lower cost—a result not currently possible with e-mode GaN.

Other specifications and features include:

  • Operation over a universal input voltage of 90 to 264 Vac
  • Over 96% peak efficiency and flat efficiency curve across line and load
  • Tight switching frequency regulation for improved input EMI filter utilization
  • Over 180 kHz switching frequency operation for compact implementation

The new reference design joins a broad portfolio of adapter/fast charger design tools offered by Transphorm. That portfolio currently includes five open-frame USB-C PD reference designs ranging from 45 to 100 watts. It also includes two open-frame USB-C PD/PPS reference designs for 65 W and 140 W adapters.

SuperGaN Technology Difference

When designing its SuperGaN platform, Transphorm’s engineering team drew on learnings from production ramps of previous products and paired that knowledge with its drive for performance, manufacturability, and cost improvements. The result was a new GaN platform comprised of patented technology offering ultimate simplicity and substantial improvements in various areas, such as:

Performance: a flatter, higher efficiency curve with an improved Figure of Merit (RON*QOSS) of ~10 percent

Designability: elimination of a switching node snubber requirement at high operation currents.

Cost: simplification of device assembly helps reduce cost.

Robustness: industry-leading gate robustness of +/- 20 Vmax and noise immunity of 4 V.

Reliability: industry-leading reliability with a < 0.10 FIT rate with 85 B+ hours of field operation.

Click here to learn more about TP65H150G4PS