New SiC SBDs for high voltage xEV systems

ROHM has developed surface mount SiC SBDs that improve insulation resistance by increasing the creepage distance between terminals. The initial lineup includes eight models – SCS2xxxNHR – for automotive applications such as OBCs, with plans to deploy eight models – SCS2xxxN – for industrial equipment such as FA devices and PV inverters in December 2024.

The rapidly expanding xEV market is driving the demand for power semiconductors, among them SiC SBDs, that deliver low heat generation along with high-speed switching and high-voltage capabilities in applications such as onboard chargers. Manufacturers also increasingly rely on compact SMDs compatible with automated assembly equipment to increase manufacturing efficiency. Compact SMDs tend to generally feature smaller creepage distances, a fact that makes high-voltage tracking prevention a critical design challenge.

As leading SiC supplier, the company has been working to develop high-performance SiC SBDs that provide breakdown voltages suitable for high-voltage applications with ease of mounting. Adopting an optimised package shape achieves a minimum creepage distance of 5.1mm, improving insulation performance when contrasted with standard products.

The new products utilise an original design that removes the centre pin previously located at the bottom of the package, extending the creepage distance to a minimum of 5.1mm, approx. 1.3 times greater than standard products. This minimises the possibility of tracking (creepage discharge) between terminals, eradicating the necessity for insulation treatment through resin potting when surface mounting the device on circuit boards in high-voltage applications. The devices can also be mounted on the same land pattern as standard and conventional TO-263 package products, enabling an easy replacement on existing circuit boards.

Two voltage ratings are offered, 650V and 1200V, supporting 400V systems commonly used in xEVs, and higher voltage systems are expected to gain wider adoption in the future. The automotive-grade SCS2xxxNHR are AEC-Q101 qualified, ensuring they satisfy the high reliability standards this application sector demands.

Application examples include automotive applications such as OBCs, DC-DC converters, etc; industrial equipment includes AC servo motors for industrial robots, PV inverters, power conditioners, UPS, and more