Blog Image

STMicro Power Modules Aim to Simplify SiC Inverter Designs

  • 2022-09-13

Leveraging the electrical characteristics of silicon-carbide (SiC), the new power modules from STMicroelectronics aim to ensure high power density while simplifying assembly.

Lately, wide-bandgap semiconductor materials are employed to manufacture electronic components such as MOSFETs for use in high power and frequency applications. Along those lines, STMicroelectronics (ST) has released a pair of silicon carbide (SiC)power modules that boast high efficiency in inverter and DC-DC converter designs.

These power modules are named ACEPACK and are aimed at a variety of power applications that range from 3 kW to 30 kW. This article discusses the ACEPACK power module package and the first two ACEPACK products ST is introducing to the market.

ACEPACK Modules with Embedded NTC Thermistor

The ACEPACK 1 and ACEPACK 2 power modules feature an embedded NTC (negative temperature coefficient) thermistor for system protection and diagnostics and are fabricated to suit different high power and frequency applications such as inverters, DC-DC converters, and industrial motor drives.


Close-up image of the ACEPACK 2 power module. Image used courtesy of STMicroelectronics

The power modules come in different converter topology designs which include ix-pack (3-phase full-bridge), converter-inverter-brake (CIB), 3-level, four-pack, and half-bridge. They are also available in different current ratings ranging from 5 A to 100 A and voltage ratings ranging from 650 V to 1200 V.

The ACEPACK power modules are well suited for applications in industrial motor drives, renewable energy systems, and more. 

The ACEPACK power modules are well suited for applications in industrial motor drives, renewable energy systems, and more. Image used courtesy of STMicroelectronics

One major advantage of using the power modules in design is that it allows designers to integrate different technologies in both silicon carbide and silicon (such as IGBTs and high-voltage MOSFETs).

In addition, developers could implement the power modules’ different converter topologies in different power switching devices. Being made from silicon-carbide, the power modules offer the best compromise between conduction and switching losses. 

According to the company, the ACEPACK 2 package in particular has compact dimensions and ensures high power density, with an efficient alumina substrate and direct bonded copper (DBC) die attachment. What’s more, the ACEPACK power modules enable designers to fabricate small-sized solutions while offering high performance and reliability.

Power Modules Use T-type Inverter Scheme

The A2F12M12W2-F1 and A2U12M12W2-F2 are the latest power modules from ST’s ACEPACK power modules portfolio. According to the company, high power converters are incorporated into the power modules for high conduction and switching efficiency with consistent output-voltage quality.

While the A2F12M12W2-F1 is a four-pack converter topology, the A2U12M12W2-F2 employs a T-type 3-level inverter topology. A T-type 3-level inverter topology incorporates a full bridge 2L inverter that is connected to three anti-series semiconductor switches in an attempt to increase converter efficiency. More information can be found in the datasheets for the A2F12M12W2-F1 and the A2U12M12W2-F2.

A three phase 3L T-type topology electrical circuit. Image used courtesy of Salem and Abidol

Furthermore, the products are both high conduction and switching efficiency with consistent output-voltage quality. With a voltage rating of 1200 V and 13 mΩ on-resistance value, they boast a high current-handling capability with minimal losses.

The two power modules offer 2.5 kVRMS insulation voltage. They also have press fit pins that simplify assembly in potentially harsh-environment equipment such as electric vehicles (EVs) and power conversion for charging stations, energy storage, and solar energy.

With these new power modules, ST hopes to continue to simplify designs and improve the efficiency of high-power devices and solutions.