Automotive WBG Power Devices - Pushing the Frontiers
As the world soldiers on in the so-called “new normal”, it is uplifting to read reports of forecast upticks in the otherwise sluggish automotive industry. BCG Consulting published a report with various post-Covid-19 scenarios, with the ‘most likely’ recovery seeing 58-59 million new vehicle sales in 2021 vs 49-53.4 million units transacted this year.
Part of this recovery will help to fuel demand for the relatively new wide bandgap (WBG) power devices such as silicon carbide (SiC) and gallium nitride (GaN) devices. This market is showing resilience despite the 2020 slowdown. Research house Omdia forecasts SiC and GaN revenue to grow pass $1 billion in 2021, boosted by demand from hybrid and electric vehicles (EV), power supplies, and photovoltaic (PV) inverters.
Both GaN and SiC WBG devices provide major leaps in switching speed (10x to 100x faster than older designs). They also operate much more efficiently at higher voltage and thermal environments, while reducing size and cost.
SiC growth is driven by new applications in the high-power EV and hybrid EV (HEV) market for charging infrastructure, and various power supply applications. The need for fast-charging technology in both portable consumer electronics devices and onboard chargers for electric vehicles (EVs) meanwhile bolsters demand for GaN.
Even as automotive power device manufacturers anticipate market recovery in the medium to longer term, they have to address a number of pressing challenges. Designers must perform both static and dynamic measurements (see Table 1) accurately to characterize the devices, and ensure they perform as designed in the harsh operating environment of the vehicle or EV supply environment (EVSE).
In addition, manufacturers must conform to the JEDEC JC-70 standards for WBG devices focused on reliability and qualification procedures, datasheet elements and parameters, as well as test and characterization methods.
Conventionally, manufacturers use power device analyzers to carry out static measurements for these power devices. As JEDEC continues to define the dynamic testing of WBG devices, the double-pulse testing method is emerging as the standard for determining performance parameters of power semiconductors.
Traditionally, WBG foundries have relied on homegrown test systems as their primary source for characterizing WBG semiconductors as commercially available test systems were not readily available. Unfortunately, it is difficult to produce repeatable and reliable measurement results with one-off, “homegrown” testers. Unreliable results create additional obstacles for power-converter designers when correlating their measurements with the semiconductor’s data sheets. In addition, it is also challenging to ensure physical safety of both engineers and devices under test in the high-power environment.
Responding to industry requirements, Keysight collaborated closely with semiconductor manufacturers and designers from the energy and electric vehicle sectors to create the Keysight PD1500A Dynamic Power Device Analyzer / Double Pulse Tester (Figure 2), a solution which can provide quick, repeatable, and reliable results. The PD1500A also supports the latest evolving JEDEC standards for WBG devices, so R&D teams can test quickly as technology evolves.
To protect the engineers, the system’s transparent hood automatically locks when more than 42 V are energized (Figure 3).
Despite the slow-down and restricted travels in recent months, Keysight continues its collaborative efforts with the automotive industry to address the challenges of designing and testing high-power semiconductor devices in anticipation of the market’s recovery.
To help you keep up to speed with these evolving high-power electronics that enable e-mobility, Keysight has created online resources accessible for you to continue learning and innovating, anywhere anytime.
Feel free to explore these resources:
Auto Pit Stop on double pulse test: In this webinar, Keysight’s high-power devices test expert Mike Hawes discusses how to achieve reliable and repeatable dynamic characterization of power semiconductors using double pulse test.