Rohm introduces SiC modules for xEV onboard chargers

ROHM Semiconductor announced the development of new 4-in-1 and 6-in-1 SiC molded modules in the HSDIP20 package optimized for PFC and LLC converters in onboard chargers (OBC) for xEVs (electric vehicles). The lineup includes six models rated at 750V (BSTxxx1P4K01) and seven products rated at 1200V (BSTxxx2P4K01). All basic circuits required for power conversion in various high-power applications are integrated into a compact module package, reducing the design workload for manufacturers and enabling the miniaturization of power conversion circuits in OBCs and other applications.

In recent years, the rapid electrification of cars has driven efforts to achieve a decarbonized society. Electric vehicles are seeing higher battery voltages to extend the cruising range and improve charging speed, creating a demand for higher output from OBCs and DC-DC converters. At the same time, there is an increasing need in the market for greater miniaturization and lighter weight for these applications, requiring technological breakthroughs to improve power density – a key factor – while enhancing heat dissipation characteristics that could otherwise hinder progress. ROHM’s HSDIP20 package addresses these technical challenges that were previously difficult to overcome with discrete configurations, contributing to both higher output and the downsizing of electric powertrains.

The HSDIP20 features an insulating substrate with excellent heat dissipation properties that suppresses the chip temperature rise even during high-power operation. When comparing a typical OBC PFC circuit utilizing six discrete SiC MOSFETs with top-side heat dissipation to ROHM’s 6-in-1 module under the same conditions, the HSDIP20 package was verified to be approximately. 38°C cooler (at 25W operation). This high heat dissipation performance supports high currents even in a compact package, achieving industry-leading power density more than 3 times higher than top-side cooled discretes and over 1.4 times that of similar DIP-type modules. As a result, in the PFC circuit mentioned above, the HSDIP20 can reduce the mounting area by approximately. 52% compared to top-side cooled discrete configurations, greatly contributing to the miniaturization of power conversion circuits in applications such as OBCs.

Going forward, ROHM will continue to advance the development of SiC modules that balance miniaturization with high efficiency while also focusing on the development of automotive SiC IPMs that provide higher reliability in a smaller form factor.

Power conversion circuits like PFC and LLC converters are commonly used in the primary side circuits of industrial equipment, allowing the HSDIP20 to also contribute to the miniaturization of applications in both the industrial and consumer electronics fields.