English
Rohm Semiconductor recently introduced its new HSDIP20 SiC power modules to improve the thermal, spatial, and power density performance of onboard chargers (OBCs) and DC-DC converters for electric vehicles.
HSDIP20 SiC power modules for automotive and industrial applications.
With performance and thermal management advances integrated into a single package, Rohm believes its new solutions could help manufacturers meet rising power output demands while reducing system size and cooling complexity.
The New High Power Density SiC Power Modules
The new HSDIP20 SiC power modules integrate either four or six SiC MOSFETs into a 38.0 mm x 31.3 mm x 3.5 mm molded package, available in two voltage classes: 750 V (BSTxxx1P4K01) and 1200 V (BSTxxx2P4K01). Options range from 25 mΩ to 90 mΩ on-resistance and target output currents of up to 90 A.
To address the mounting demands for higher OBC power output and reduced system size, Rohm incorporated an insulating substrate with high thermal conductivity, which reduces junction temperatures by approximately 38°C compared to equivalent discrete SiC MOSFET configurations at 25-W input.
By combining low on-resistance SiC MOSFETs with a high thermal conductivity package, the HSDIP20 modules achieve more than three times the power density of conventional discrete solutions and 1.5 times that of comparable DIP modules. Rohm claims that this advancement reduces the mounting area by 52% for power factor correction (PFC) circuits.
Benefits of Rohm’s new packaging technology.
The new module's structure simplifies circuit layout by integrating full-bridge and three-phase topologies directly into the package. Evaluation kits are available specifically for double-pulse testing and three-phase full-bridge applications.
The Thermal Bottleneck in OBC and DC-DC Converters
The drive toward higher output OBCs and DC-DC converters in electric vehicles has intensified the thermal management challenges that power electronics designers face. As battery voltages rise to 800 V and beyond to enable faster charging and longer range, OBC output requirements have expanded from 6.6-kW systems to designs routinely exceeding 11 kW and approaching 22 kW. This upward trajectory requires higher-power switching devices and greater thermal efficiency to prevent excessive junction temperatures that degrade reliability.
Traditional discrete-based configurations, even those utilizing SiC MOSFETs with top-side cooling, encounter severe thermal bottlenecks when scaled to meet these new performance thresholds. The cumulative thermal resistance from the device junction through the package to the heat sink introduces significant thermal impedance, which forces designers to derate power stages or adopt bulkier thermal solutions. Furthermore, uneven thermal distribution across multiple discrete components complicates thermal modeling and can create localized hotspots that accelerate device degradation.
Improved thermal dissipation suppresses heat generation in the HSDIP20 modules.
Rohm is answering the call with molded SiC modules that integrate low on-resistance devices and optimized thermal pathways. By embedding multiple power devices within a single high-conductivity insulating substrate and minimizing the thermal interface layers, modules like Rohm’s HSDIP20 reduce thermal resistance and improve uniformity of heat dissipation. This, in turn, enables higher continuous currents at lower junction temperatures.
Demands on Power Module Design
As electric vehicle platforms pursue even higher power transfer rates and more aggressive miniaturization targets, tightly controlled thermal performance at the package level will be a central design constraint. Rohm’s HSDIP20 modules innovate power semiconductor packaging to meet automotive and industrial requirements. Samples of the HSDIP20 modules are currently available, with volume quantities slated for release soon.
