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Silicon carbide (SiC) and gallium nitride (GaN), widely considered the future of energy conversion, were the prominent highlight of APEC 2023 in Orlando, Florida. According to the figures provided in a presentation by Navitas Semiconductor, these two semiconductor technologies are predicted to win 30% of the $22 billion per year silicon power market by 2027.
However, when it comes to new horizons in power electronics, the paths of these two wide bandgap (WBG) materials are increasingly intertwined. APEC 2023 provided a reality check regarding which WBG technology stands where and what their respective product roadmaps look like.

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Figure 1 APEC 2023 was a good venue to explore GaN technology and application roadmap. Source: Efficient Power Conversion (EPC)
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GaN power devices, the focus of this article, have been in volume production for over 13 years with hundreds of millions of transistors and ICs employed in a broad span of applications. Take, for instance, consumer adapters, where GaN semiconductors have reduced the size by nearly 50% and improved efficiency by up to 94%. These devices are now commonly used in AC/DC designs under 75 W for their energy efficiency and power density advantages.
At APEC 2023, GaN devices powering fast chargers for smartphones, laptops, and tablets as well as multi-kW platform designs for AC-DC supplies for data centers were a prominent display. However, what took the center stage at APEC was GaN’s place in the quickly evolving electric vehicle (EV) design landscape. How realistic is this premise, and when will this happen? Talking to major GaN semiconductor suppliers on the APEC floor provided much-needed clarity.
GaN in EVs
GaN semiconductors, broadly targeting 80-V to 650-V applications, enable new power supply and audio fidelity horizons while facilitating medium power and high switching frequency. According to Andre Christmann, principal application engineer at Infineon Technologies, while GaN technology is accelerating, it won’t be important in the automotive market till 2025. “GaN might compete with silicon and SiC technologies in the onboard charger (OBC) and DC/DC converter markets after 2025.”
Market research firm IDTechEx, which recently published a report titled “Power Electronics for Electric Vehicles 2023-2033,” agrees with the premise that OBCs and DC/DC converters will be the first market entry point for GaN power devices. That’s because OBCs and DC/DC converters operate at much lower powers. Moreover, the efficiency advantage of GaN materials is a clear driver for faster AC charging or internal charging of the battery.
Philip Zuk, senior VP of technical marketing and business development at Transphorm, seemed more optimistic regarding GaN’s merits in the automotive market. “Over time, GaN is going to own the DC/DC converter and OBC markets because it’s cheaper and far more efficient,” he said. For traction inverters, Zuk says that GaN devices have a play in small electric cars below 50 W.
He mentioned Transphorm’s upcoming 1,200 V semiconductors, built with GaN-on-sapphire, which could be incorporated into e-bikes and e-scooters. “The question is how fast it’s going to be adopted.” Transphorm’s 1,200 V GaN semiconductors will start sampling toward the end of 2023.

Figure 2 GaN technology, commonly identified with 650-V devices, will soon have a new kid on the WBG block, a 1,200-V FET. Source: Transphorm
Transphorm, founded in 2007, claims to be the first supplier of GaN semiconductors that are JEDEC- and automotive-qualified. Its portfolio includes 650-V and 900-V FETs, while 1,200-V FETs are currently under development. However, Zuk acknowledges that 900-V devices are more of a showpiece, demonstrating that we can do more than 650-V GaN.
“The 900-V GaN devices will go away because they aren’t just high enough,” Zuke added. “It’s the 1,200 V technology we are very excited about as it opens new venues like 800-V battery EVs, solar infrastructure, and high-power charging.”
Besides Tramsphorm, another company vying for GaN’s greater role in EVs is VisIC Technologies. It has employed 650-V GaN chips to develop an EV inverter design in partnership with Hofer Powertrain. At APEC 2023, the Israel-based company’s co-founder and CEO Tamara Baksht presented details of a GaN-based three-phase inverter reference design with 400-V bus voltage and 400-A RMS current.
GaN beyond EVs
Of course, there is more to GaN promise than sockets in EV designs. Navitas Semiconductor, which announced to have shipped 75 million high-voltage GaN units, was quick to note that the GaN market for data centers is ramping up. Stephen Oliver, VP of corporate marketing at Navitas Semiconductor, also mentioned motor drives for home appliances and industrial markets as a promising new venue for GaN devices.
“Motor drives can be made more efficient, smaller, and lighter with GaN in applications like vacuum cleaners, refrigerator compressors, washing machines, and dryers,” Oliver said. “Residential solar inverters could be next where GaN brings an estimated 25% system cost saving compared to legacy silicon solutions due to high-frequency operation and integration.”
For EVs, Oliver acknowledges a potential for GaN in traction in 400-V battery systems, but he is quick to note that SiC will take the major chunk of business. “The first place for GaN will be fast chargers and DC/DC converters,” he said. “For traction drive, GaN being a 700-V technology could be used in 400-V battery systems.” But there is a point where SiC takes over as the power level rises to 800-V battery cars, Oliver added.
He also talked about the company’s latest GaN-related development: GaNSense Control ICs, a silicon-based low-voltage system controller integrated with GaN ICs (Figure 3). “GaNSense Control ICs combine high-voltage GaN power ICs with high-speed, low-voltage silicon system controllers to bolster ease-of-use and system performance,” Oliver said. “Adding a system controller optimizes the overall power system by adding autonomous sensing and fast control.”

Figure 3 The new chipset design integrates GaN ICs with silicon-based system-control chips. Source: Navitas Semiconductor
GaN’s 2023 outlook
Still, there was more to GaN at APEC, a major industry reference point for power and analog design engineering. For instance, how gate drivers complement WGB devices like 650 V GaN FETs. Another session focusing on GaN power devices highlighted design issues related to GaN HEMTs, shedding light on areas such as circuit breakers, on-resistance stability, and over-voltage switching.
Cambridge GaN Devices (CGD) provided technical details about its 650-V transistors for high-voltage applications (Figure 4). The ICe-GaN device comes integrated with current sensing and Miller clamp for safe turn-off, gate protection, and electrostatic discharge (ESD) protection.

Figure 4 The ICe-GaN transistors can operate like silicon MOSFET without special gate drivers, driving circuitry, or unique gate voltage clamping mechanisms. Source: Cambridge GaN Devices (CGD)
In the final analysis, two things seem apparent in GaN’s journey in the power electronics realm. First, as noted by Alex Lidow, founder and CEO of Efficient Power Conversion (EPC), GaN still has a long way to go before it reaches a state of maturity similar to silicon power devices. Second, GaN devices are increasingly eyeing the highly lucrative EV designs, currently a territory of silicon and SiC devices. “With 1,200 V GaN transistors, we are coming for you, SiC,” said Transphorm’s Zuk.
That may sound a bit exuberant, but Infineon’s Christmann made a similar statement in his presentation “Power Electronic in Electrified Powertrain” at APEC 2023. “Automotive is all about cost,” he said. “And GaN’s value proposition comes down to cost, cost, and cost.”
So, besides much-anticipated consolidation in the GaN industry following Infineon’s acquisition of GAN Systems, it’ll be worth watching how this WBG technology prepares in 2023 to claim a stake in the crucial EV market. Meanwhile, its place in markets such as consumer chargers, data center power supplies, and solar infrastructure seems highly promising.
What an ascension in less than a decade.
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