New Industry Products

Keysight and Transphorm Unveil A Reference Design For GaN-Based Switched Mode Power Supplies

March 03, 2021 by Gary Elinoff

The aim of the project is to tackle the EMI that often results from the high switching speeds that are otherwise one of the main benefits of gallium nitride (GaN) designs.

Switched-mode power supplies (SMPS) that are based on GaN can be switched at very high speeds. That means filtering components are smaller, resulting in lighter, cheaper designs that take up less space. But the potential for damaging electromagnetic interference (EMI) is a real hazard that must be ameliorated through optimized layout design and placement of components 


The Basis of the New Reference Design

As described in the Keysight product announcement, Transphorm’s contribution to the effort is its TDTTP4000W066C 4-kilowatt evaluation board. This unit features Transphorm’s own GaN FET devices, as well as Microchip’s dsPIC digital signal converters.

The TDTTP4000W066C-KIT. Image courtesy of Transphorm
The TDTTP4000W066C-KIT. Image courtesy of Transphorm


The Kit enables designers to visualize and optimize both the time and the frequency domain behavior of voltages, currents and electromagnetic fields. 

The unit features Transphorm’s TP65H035G4WS GaN FETS switching at frequencies of up to 66 kHz. Products based the TDTTP4000W066C-KIT are suited for industrial and data center power supplies. Efficiencies even at the full output of 4 kW are speced at better than 98.55%. Transphorm does caution, however, that the kit itself is for evaluation purposes only.

The second part of the story is the power supply Reference Design, which is available with Keysight's PathWave Advanced Design System. The reference design is a virtual prototype of the already mentioned TDTTP4000W066C 4 kilowatt evaluation board. It simulates the components and potential board layouts, enabling designers to observe and improve the frequency and time domain behaviors of their own design’s currents, voltages as well as the resulting magnetic fields.


Virtual and Physical Prototypes

They back each other up. Physical prototypes, of course are the gold standard. But they are expensive, and present many challenges. Virtual prototypes can be modified with a few strokes of an  engineer’s keyboard. Keysight's PathWave Advanced Design System (ADS) software provides that crucial,  virtual prototype, eliminating the need designers to invest the time involved in building a virtual simulator from the ground up. The result can be a smoother design pathway and quicker time to market for OEM designs.

As explained by Tom Lillig, general manager of Keysight's PathWave Software Solutions division, "The need for switch-mode power supplies is driving rapid adoption of wide bandgap semiconductors." He goes on to state that, "The new reference design of Transphorm's high voltage GaN solution will speed time to market of this technology, which is changing how the world powers electronic products." 

Philip Zuk, vice president of Worldwide Technical Marketing and North American Sales, Transphorm, also see great value in virtual modeling of electronic systems. As he describes it, “With proper modeling, analysis of any design type prior to physical prototyping is a useful resource. Teaming with Keysight enables us to bring our 4 kW AC-DC power conversion board into a virtual design environment that will be advantageous to product designers." 


Transphorm Looks for Partners

Zuk points out that "Transphorm looks for partnerships that help our customers close skill gaps, increase design simplicity and reduce time to market." We have previously reported on a project that Transphorm conducted with Bel Power. Here Transphorm once again calls on its GaN FETs. In this previous case, the collaborative products were commercial, non-prototype power supplies in the 1.5 to 3.2-kilowatt range.