SemiQ Introduces New High-Frequency, High-Power SiC MOSFET Modules

February 22, 2024 by Duane Benson

The five new parts are 1,200-V, full-bridge quad MOSFETs with current ratings from 27–102 A and RDS(on) values ranging from 20 to 80 mΩ.

SemiQ has added to its silicon carbide (SiC) N-channel MOSFET portfolio with a set of full-wave, H-bridge modules. The parts are designed for triple-threat applications that need high-voltage, high-speed, and high-power parts. They have been optimized for ultra-low switching losses for improved efficiency and low power losses. The high efficiency, high junction temperature tolerance, and ceramic packaging reduce heat sinking and increase mechanical placement flexibility.


Ceramic packaged SiC full H-bridge module

Ceramic-packaged, full H-bridge SiC module.

The ceramic packaging has provisions for directly mounting heatsinks on an isolated thermal pad. The electrical pin contacts are through-hole, press-fit connections with a total part footprint of 62.8 mm x 33.8 mm x 12 mm. Delivering the component in a full H-bridge module reduces assembly costs and cuts switching losses.


Valuable Additions to a Specialized Product Line

The five new partsGCMX020A120B2H1P, GCMX040A120B2H1P, GCMX080A120B2H1P, GCMX020A120B3H1P, and GCMX040A120B3H1P—are all rated at 1,200 V, with a breakdown voltage exceeding 1,400 V and a maximum junction temperature of 175°C. They all share the same ceramic press-fit, through-hole package. Maximum current capacity ranges from 27 A for the GCMX080A120B2H1P up to 102 A for the GCMX020A120B2H1P.

SemiQ has an extensive line of high-power SiC devices, including discrete MOSFETs, Schottky diodes, and half-bridge modules. The addition of full H-bridge SiC modules allows designers of high-power electronics to reduce parts count, decrease product size, and access more efficient cooling.

When one MOSFET tests poorly in a discrete H-bridge, only the failing part needs to be dropped out. In a module, one bad part necessitates discarding the entire bridge. SemiQ recognizes this risk and mitigates it by test and burn-in at the wafer level. SemiQ uses these wafer-level tests to ensure gate oxide quality and stable gate threshold voltage throughout the module.

The burn-in and test also assesses gate stress, high-temperature reverse bias drain stress, high humidity, high voltage, and high-temperature reliance. The result is an automotive- and industrial-grade product with generous environmental headroom and a low chance of early-life failure.


SiC MOSFETs Flaunt Major Advantage in DC Applications

The new SiC MOSFETs are suited for power-intensive DC applications such as solar power inverters, electric vehicle chargers, energy storage systems, and DC-DC converters. All of these applications require high voltages, high switching frequencies, and high power capacity. SemiQ designed its new line specifically for high-power applications that need the efficiencies that come with high switching frequencies and high operating voltages.

Green energy and massive server power requirements are in the DC realm. Unfortunately, DC voltage conversion is far more complex than the simple coupled-inductor transformer that is used for alternating current. DC voltage conversion requires a switch mode power supply (SMPS). Higher switching frequencies deliver better efficiency if the semiconductor material can keep up. SiC is one of the materials that keeps up far better than silicon. These parts have enabled SMPS efficiencies to increase from the 90% range to the 98% percent range.


Typical solar inverter circuit

Typical solar inverter circuit.

That’s not just an 8% improvement. Switching losses are what cause power waste and heat. In a conventional semiconductor, the losses are around 10% of the current flow. The other 90% is going through to the application. SiC sends that 90% through as well as 80% of the losses. That means 8% more current flow but an 80% reduction in waste and heat.

While DC is used as the end power in electronics, most electric vehicles still use AC motors due to their superior efficiencies. These electric motors operate in the kilowatt range of 300–600 V. Without such high voltages, the current draw for a 50+ kW motor would make the wiring, heat sinking, and motors too heavy to be practical. SiC devices, like the five new 1,200-V, full-bridge quad MOSFETs from SemiQ, can handle the load more efficiently than standard silicon.



All images used courtesy of SemiQ.