Qorvo Acquires UnitedSiC, Snapping Up More of the Wide Bandgap Market

November 10, 2021 by Adrian Gibbons

In a bid to expand into new power markets, RF giant Qorvo has acquired UnitedSiC, a pioneer in SiC FET technology.

In a year where acquisitions are changing the landscape of semiconductor business ownership, Qorvo is stepping up to the plate for a second time after acquiring NextInput in the second quarter of 2021

Last week Qorvo, an RF industry giant, announced its acquisition of UnitedSiC; in doing so, Qorvo is reaching deeper into several markets including electric vehicles and industrial power.


Projecting the growth of SiC-based devices

Projection of the growth of SiC-based devices. 


What gains is Qorvo seeking with this acquisition? What does UnitedSiC bring to the table in terms of expertise or industry-leading solutions?

In this article, we'll look at these questions while also assessing the notion of industrial power distribution—an area of interest for Qorvo—by discussing how UnitedSiC achieves 99.3 percent efficiency in a power factor correction.  


Market Positions for Qorvo and UnitedSiC

Qorvo has positioned itself as an innovator of RF-related solutions with expertise in wired and wireless devices and networks as well as defense radar and communications. 

For the past several years Qorvo has been focused on GaN technology. Notable solutions based on GaN devices include single-band and dual-band reconfigurable power amplifiers (2021), and GaN-on-SiC transistors (2018) for kW switching L-band avionics applications. 

UnitedSiC, as one might assume, has a portfolio providing silicon carbide solutions based on FETs, MOSFETs, and Schottky Diodes. UnitedSiC recently announced a 750 V 6 mOhm SiC FET, which is said to have the lowest RDS(on) in the industry for SiC MOSFET devices.  

Philip Chesley, president of Qorvo’s infrastructure and defense products, indicates that the acquisition “significantly expands [Qorvo's] market opportunities in high-power applications.”


Why Did Qorvo Acquire UnitedSiC?

Qorvo appears to have taken advantage of UnitedSiC’s position as the industry leader in silicon carbide technologies with this acquisition. UnitedSiC has a full-range portfolio of SiC FET technology operating at 750 V/650 V with RDS(on) values between 6 mOhms and 60 mOhms.


UnitedSiC’s SiC MOSFETs

UnitedSiC’s SiC MOSFETs claim to have the industry’s lowest RDS(on)


Released this year, UnitedSiC Generation 4 SiC FETS are cascode-based devices (SiC JFETs packaged with silicon MOSFETs), which are said to offer high speeds, low losses at high temperatures, and stable gate drive characteristics.

What applications can benefit from these newest generations of SiC FETs? The answer may be directly applicable for power engineers. 


Gen4 SiC FETs Are Designed With Power Engineers in Mind

Power usage affects every member of society, but for engineers working in power distribution roles, few parameters are more important than power factors. Power factor is the relationship between real power (watts) and reactive power (volt-amp-reactive)

UnitedSiC’s newest generation of SiC FETs can achieve 99.3 percent efficiency in totem-pole power factor correction for AC-DC conversion applications using continuous conduction mode (CCM) operation at 3.6 kW.


Power factor

Achieving 99% efficiency from 42% to 100% load. 


Conduction losses are minimized by moving from a conventional full-wave diode PFC rectifier to a bridgeless totem-pole PFC (TPPFC). 


Full-wave bridge rectifier and a bridgeless totem-pole PFC

Full-wave bridge rectifier (left) and a bridgeless totem-pole PFC (right).


Previously, silicon-based TPPFC devices have been limited to a complex mode of operation called critical conduction mode (CrM) due to high reverse recovery charge (Qrr). Gen4 SiC FETs are said to remove this limitation and allow the use of the less complex CCM. 

There are trade-offs to CrM and CCM operations. However, one of the key advantages to moving from CrM to CCM is an improvement in EMI emissions by limiting the generation of harmonics.


Qorvo Claims Its Stake of WBG Semiconductors

With the acquisition of UnitedSiC, Qorvo appears to have positioned itself well to expand into new markets beyond RF—specifically in EVs, circuit protection, industrial power, renewables, and data center power. UnitedSiC holds an impressive assortment of switching technologies based on silicon-carbide semiconductors that may help in this endeavor. 

Wideband gap technologies like GaN and SiC are becoming increasingly important with the electrification of our society. The ability to operate at higher voltages in various environments with low losses is critical to future power infrastructure development.


All images used courtesy of UnitedSiC.