SiC and GaN power ICs rule at APEC 2024

Manufacturers of silicon carbide (SiC) and gallium nitride (GaN) power ICs leveraged the APEC 2024 conference to highlight their latest developments in wide-bandgap semiconductors. These devices offer several advantages over silicon counterparts, including higher efficiency, higher power density and faster switching. They can also handle higher voltages, temperatures and frequencies.

The SiC ecosystem is growing fast and moving steadily into a maturing segment, as more industry sectors demand energy-efficiency solutions. SiC power ICs are used in a range of automotive and industrial applications.

Although the SiC power IC segment is moving into the maturity phase, with its growing ecosystem, there are still plenty of advances on the horizon. Power IC suppliers continue to add new features that address key design challenges like heat dissipation and electromagnetic compatibility (EMC). Another trend is the availability of both discrete and module devices.

Now that GaN FETs have won a lot of designs in consumer electronics applications like mobile fast chargers and adapters, they are increasingly targeting higher-reliability applications like data centers, electric vehicles, industrial and renewable energy (solar). They are also getting new features like better electromagnetic-interference (EMI) capabilities and circuit protection.

Here is a sampling of new SiC and GaN power ICs launched at the show. Many of these devices also feature higher integration for performance improvements as well as space and cost savings.

SiC power ICs

SiC power ICs offer a range of benefits, including faster switching, higher efficiency and higher-voltage operation and they can withstand higher temperatures, all contributing to smaller designs. Because SiC devices can operate at higher voltages and currents, they offer increased power density and lower switching losses even at high temperatures.

A big driver of SiC MOSFETs, today and in the future, is EV power electronics. Here, they offer higher powertrain efficiency for longer range and higher voltages for faster charging, two huge issues for consumers. Other big markets for SiC power management are industrial, data centers, renewable energy, solar power and 5G.

Infineon Technologies AG introduced its latest CoolSiC MOSFET, which addresses the need for higher efficiency and power density in industrial and automotive power applications. The new 750-V G1 discrete CoolSiC MOSFET family is optimized for totem-pole PFC, T-type, LLC/CLLC, dual active bridge, HERIC, buck-boost and phase-shifted full-bridge topologies. Their design delivers lower conduction and switching losses, which increases overall system efficiency.

Target industrial applications are industrial drives, solar and energy storage systems, solid-state circuit breakers, UPS systems, servers/data centers and telecommunications. Automotive applications include EV charging, on-board chargers and DC/DC converters.

The devices in the portfolio range from 8- to 140-mΩ R_DS(on) at 25°C. Infineon said they provide excellent R_DS(on) × Q_fr and R_DS(on) × Q_oss figures of merit, delivering ultra-high efficiency in hard-switching and soft-switching topologies. The combination of high threshold voltage (V_GS(th), typ. of 4.3 V) with low Q_GD/Q_GS ratio ensures protection against parasitic turn-on and enables unipolar gate driving, with the benefits of increased power density and lower system costs.

Their packages minimize thermal resistance for improved heat dissipation and optimize in-circuit power-loop inductance, also contributing to higher power density and lower system costs, Infineon said. The automotive-grade devices are housed in QDPAK top-side–cooled (TSC), D2PAK-7L and TO-247-4 packages, while the industrial-grade MOSFETs are available in QDPAK TSC and TO-247-4 packages.

Microchip Technology Inc. expanded its mSiC gate driver family with the introduction of the 3.3-kV XIFM plug-and-play mSiC gate driver. The devices are aimed at helping developers implement SiC solutions as electrification drives the widespread adoption of SiC technology in medium- to high-voltage applications like transportation, electric grids and heavy-duty vehicles. Targeting high-voltage SiC power modules, the new mSiC gate driver features patented Augmented Switching technology, which is designed to work out of the box with preconfigured module settings to reduce design and evaluation time.

The plug-and-play solution simplifies a lot of the development for design, test and qualification of a gate-driver circuit design, Microchip said. The highly integrated digital gate driver features digital control, an integrated power supply and a fiber-optic interface that improves noise immunity. It also has preconfigured “turn-on/-off” gate-drive profiles that are tailored to optimize module performance.

Other features include 10.2-kV primary-to-secondary reinforced isolation with built-in monitoring and protection functions, such as temperature and DC-link monitoring, undervoltage lockout, overvoltage lockout, short-circuit/overcurrent protection and negative temperature coefficient. The gate driver complies with EN 50155, a key specification for railway applications.

E-mobility is a big application for SiC, and Cissoid has announced a new series of SiC inverter control modules (ICMs) that help engineers develop functionally safe and modular electric motor drives while reducing time to market.

The new CXT-ICM3SA series offers hardware and software integration of the company’s existing line of three-phase 1,200-V/340- to 550-A SiC MOSFET intelligent power modules with an OLEA T222 field-programmable control unit (FPCU) control board and OLEA APP INVERTER application software, supplied in partnership with Silicon Mobility. Both the FPCU and the control software are ISO 26262 ASIL C/D–certified and AUTOSAR 4.3–compliant.

The integration helps accelerate the development of SiC inverters by solving EMC issues often due to fast-switching SiC transistors. This is achieved by supporting different modulation schemes, such as SVPWM or DPWM, combined with deadtime compensation, and by offering advanced motor control algorithms, including field-oriented control and flux-weakening management, the company said.

Depending on the ICM product, this modular core engine is capable of powering and controlling high-voltage SiC traction inverters with battery voltages up to 850 V, at output power in excess of 350 kW and with peak efficiency above 99%, Cissoid said. The ICM also enables high switching frequencies up to 50 kHz thanks to the combination of the low-loss SiC power module and ultra-fast real-time FPCU.

Cissoid offers a complete SiC inverter reference design that allows motor bench testing of the ICM together with key peripheral elements, such as current sensors, a high-performance DC-link capacitor and EMI filter.

Targeting both EV charging and solar inverters, SemiQ Inc. expanded its compact family of QSiC 1,200-V SiC MOSFET modules with new full-bridge configurations. These modules deliver near-zero switching loss, providing greater efficiency, reducing heat dissipation and allowing the use of smaller heat sinks.

The MOSFET modules, tested to above 1,400 V, are designed for high-frequency and high-power environments for demanding applications that require bidirectional power flow or a broad range of control. Applications include solar inverters, drives and chargers for EVs, DC/DC converters and power supplies.

The QSiC 1,200-V SiC MOSFET modules help reduce heat loss, improve thermal stability and enhance reliability, SemiQ said. They are made from high-performance ceramics and are backed by over 54 million hours of HTRB/H3TRB testing.

In full-bridge configurations, they can withstand high-temperature operation at T_j = 175°C with minimal R_DS(on) shift over the entire temperature range. When used in solar inverter applications, the modules reach as high as 98% efficiency in more compact designs.

The 1,200-V MOSFETs also improve efficiency and reliability in DC/DC converters while minimizing power dissipation. These modules in full-bridge packages are currently available with 20-mΩ, 40-mΩ and 80-mΩ ratings. The devices also offer extended short-circuit ratings.

Also introducing new 1,200-V SiC modules in small packages is Qorvo. The company launched four 1,200-V SiC modules—two half-bridge and two full-bridge—in a compact E1B package with R_DS(on) starting at 9.4 mΩ. These SiC modules target EV charging stations, energy storage, industrial power supplies and solar power applications.

These four SiC modules leverage Qorvo’s unique cascode configuration, which minimizes R_DS(on) and switching losses to maximize efficiency, especially in soft-switching applications, Qorvo said. In addition, due to the higher switching frequency operation, thanks to the cascode technology, it further reduces solution size by using smaller components.

These modules can replace as many as four discrete SiC FETs, which simplifies thermomechanical design and assembly, the company said. They also streamline the power supply design process by qualifying one module instead of several discrete components.

The power modules feature silver-sinter die attach, which is reported to reduce thermal resistance to as low as 0.23°C/W, and when combined with the stacked die construction (the “SC” part numbers), power-cycling performance is improved by 2× over comparable SiC power modules on the market, Qorvo said.

GaN power ICs

While GaN delivers higher switching frequencies, the big advantage of GaN is its higher power density, which allows for a smaller size, resulting in a reduction in overall system size without compromising performance. The demand for more efficient power electronics in wireless charging, data centers and renewable energy is driving the adoption of GaN power ICs.

Power Integrations has unveiled its InnoMux-2 family of single-stage, independently regulated multi-output offline GaN-based power supply ICs. These GaN switcher ICs incorporate AC/DC and downstream DC/DC conversion stages in a single chip and provide up to three independently regulated outputs for applications like white goods, industrial systems, displays and other applications requiring multiple voltages.

These GaN-based switcher ICs, by combining the AC/DC and DC/DC stages into a single power converter, cut power system losses by up to 50%, according to the company.

Power Integrations explained that most modern electronic systems use multiple internal voltages to operate various functions—such as computing, communication and actuation functions—but losses in each conversion stage are compounded, which degrades system performance and generates heat.

The InnoMux-2 IC solves this challenge by providing up to three independently regulated voltage outputs or two voltage outputs and a constant-current output from a single stage.

By eliminating the separate DC/DC stages, it reduces component count and PCB footprint while increasing efficiency by as much as 10 percentage points compared with traditional two-stage architectures, the company said. Also contributing to the InnoMux-2 family’s efficiency are the 750-V PowiGaN GaN transistors, zero-voltage switching (without an active clamp) and synchronous rectification.

These switcher ICs deliver up to 90 W of output power with accurate regulation of better than ±3% across the full input line, load, temperature and differential current step conditions. It also provides total power system efficiency of about 90%. Because the InnoMux-2 controller also manages light-load power delivery, it eliminates the need for pre-load resistors and reduces no-load consumption to less than 30 mW, which conserves power for necessary functionality in applications subject to the 300-mW allowance for standby usage under the European energy-using product (EuP) regulations, the company said.

InnoMux-2 devices are housed in thermally efficient InSOP24 and InSOP28 packages with PCB cooling, eliminating the need for a heat sink. Applications include TVs, monitors, appliances, networking, home and building automation, LED emergency lighting and industrial power supplies.

Efficient Power Conversion Corp. (EPC) has claimed the lowest-R_DS(on) GaN FET on the market, with double the power density compared with EPC’s prior-generation products. The new 100-V, 1-mΩ EPC2361 GaN FET has a typical R_DS(on) of 1-mΩ in a thermally enhanced 3 × 5-mm QFN package. The maximum R_DS(on) × area of the device is 15 mΩ mm², which is more than 5× smaller than comparable 100-V silicon MOSFETs, according to EPC.

With its ultra-low R_DS(on), the EPC2361 GaN power transistor enables higher power density and efficiency in power-conversion systems, resulting in lower energy consumption and heat dissipation. The ultra-low R_DS(on) is particularly significant for applications like high-power PSU AC/DC synchronous rectification, high-frequency DC/DC conversion for data centers, motor drives for e-mobility, robotics, drones and solar MPPTs.

EPC also offers the EPC90156 100-V, 65-A half-bridge 2 × 2-inch (50.8 × 50.8-mm) development board, featuring the EPC2361 GaN FET and all critical components.

Another space saver is Innoscience’s family of integrated GaN HEMT ICs. This family of four new integrated devices combines a GaN HEMT, gate driver, current sense, protection and other functions in a single, industry-standard QFN 6 × 8-mm package. The 700-V ISG610x SolidGaN GaN HEMT ICs save board space and reduce component count while increasing efficiency and simplifying design for applications including USB-PD chargers, LED lighting, and AC/DC power supplies, as well as PFC, QR flyback, ACF, and LLC converters.

The integrated ISG610x SolidGaN GaN HEMT ICs cover the range from 140 mΩ to 450 mΩ and offer a wide 9-V to 80-V V_CC range, which benefits USB-PD applications that require up to 28-V output, Innoscience said.

The SolidGaN parts can cover the USB-PD output voltage requirements without an external LDO or other parts, in comparison with competitive devices with a limited 30-V input voltage that requires an external high-voltage LDO or several discrete components to achieve higher than 15-V output, the company said. In addition, the family’s loss-less current sensing with 7% accuracy contributes to a reduction in cost, component count and PCB space.

For low-power operation, the ISG610x family provides a low 115-µA quiescent current, thanks to an automatic standby mode that is activated when the PWM signal voltage remains low for a certain time period. Other features include a programmable switch turn-on slew rate to enable EMI reduction, an internal linear voltage regulator and built-in protection, including undervoltage lockout, overcurrent protection and overtemperature protection.

A demo board, INNDAD120B1, is available for a quasi-resonant flyback power supply with 90-V to 264-VAC input and 5-V/3-A, 9-V/3-A, 12-V/3-A, 15-V/3-A, 20-V/6-A (120-W peak) output.

Texas Instruments Inc.’s newest GaN power devices focus on delivering higher power density, along with improvements in efficiency and thermal management, as well as reducing overall system costs.

The new 100-V GaN power stages, the LMG2100R044 and LMG3100R017 with thermally enhanced dual-side–cooled package technology, are designed to simplify thermal designs, reduce power supply solution size and deliver high power density for mid-voltage applications. Four target markets include solar energy, servers, telecommunications and industrial motor drives.

With the new 100-V GaN power stages, designers can reduce the power supply solution size for mid-voltage power applications and achieve industry-leading power density of over 1.5 kW/in.³, which is enabled by GaN technology’s low switching losses and higher switching frequency.

TI said the integration of GaN FETs and gate driver into a single multi-chip package will shrink the required board area for the power supply solution by over 40% compared with a discrete implementation while reducing the bill of materials and simplifying the board layout.

The new devices reduce switching power losses by 50%, compared with silicon-based solutions, while achieving 98% or higher system efficiency, compared with 94% to 96% for silicon and discrete solutions, and with 60% lower output capacitance and 50% lower gate-drive losses.

The GaN power stages also help reduce system costs with a simplified thermal design and by enabling a high switching frequency. It also makes it easier for designers to meet their thermal design targets and reduce their overall system sizes, TI said.

New for the 100-V power space, the dual-side–cooled package technology enables more efficient heat removal from both sides of the device and offers improved thermal resistance compared with competing integrated GaN devices.

The improved thermal dissipation allows for the use of smaller heat sinks to dissipate the heat. Plus, these devices allow engineers to use much smaller passives.

The GaN power stages are optimized for common topologies, including buck converters, boost converters, buck-boost converters, LLC converters, PSFB, BLDC motor drives and Class D audio.