2-in-1 SiC moulded module achieves high design flexibility and power density

ROHM has developed the 'DOT-247', a 2-in-1 SiC moulded module (SCZ40xxDTx, SCZ40xxKTx), ideal for industrial applications such as PV inverters, UPS systems, and semiconductor relays. The module retains the versatility of the widely adopted 'TO-247' package while achieving high design flexibility and power density.

The DOT-247 features a combined structure consisting of two TO-247 packages. This design allows the use of large chips, which were structurally difficult to accommodate in the TO-247 package, and accomplishes low on-resistance through a unique internal structure. Furthermore, through an optimised package structure, thermal resistance has been reduced by approximately 15% and inductance by approximately 50% compared to the TO-247. This allows a power density 2.3 times higher than the TO-247 in a half-bridge configuration – achieving the same power conversion circuit in approximately half the volume.

The new products featuring the DOT-247 package are obtainable in two topologies: half-bridge and common-source. Currently, two-level inverters are the mainstream in PV inverters, but there is growing demand for multi-level circuits such as three-level NPC, three-level T-NPC, and five-level ANPC to satisfy the need for higher voltages. In the switching sections of these circuits, topologies such as half-bridge and common source are mixed, making custom products required in many cases when using conventional SiC modules.

To address this challenge, the company has developed each of these two topologies – the smallest building blocks of multi-level circuits – into a 2-in-1 module. This allows for flexibility to support various configurations, such as NPC circuits and DC-DC converters, while significantly reducing the number of components and mounting area, and achieving circuit miniaturisation compared to discrete components.

Evaluation boards will also be made available progressively to enable evaluation during application design.

Application examples include PV inverters, semiconductor relays, UPS, ePTO, and boost converters for FCVs, AI servers (eFuse), and EV charging stations.