Miniature low-ohm shunt resistors handle 10 W

ROHM Semiconductor announced the development of the GMR320 series of shunt resistors featuring a rated power of 10W, the largest in the high-power, low-ohmic GMR lineup designed for high-power applications in the automotive, industrial equipment, and home appliance sectors.

Recent years have seen an increasing demand in the automotive and industrial fields for higher power applications that consume less power. This in turn requires shunt resistors that support high accuracy current detection to achieve energy-efficient drive in a variety of applications. ROHM’s GMR series of shunt resistors enables high accuracy driving even at high power, making them ideal for applications in the automotive, industrial, and consumer sectors.

The newly developed GMR320 series is offered in a resistance range from 5mΩ to 100mΩ and a rated power of 10W, making them ideal for vehicle ECUs and headlamps, as well as motors and power supplies for industrial equipment and home appliances. Unique materials and structure allow ROHM to reduce surface temperature rise by 23% over standard products, ensuring high durability against overcurrent loads, while superior heat dissipation makes it possible to achieve stable performance and the smallest size (7.1mm x 4.2mm) in the 10W class without a change in resistance value even at overcurrent loads.

At the same time, adopting a high-performance metal alloy as the resistive element provides a superior TCR of ±25ppm/°C or less – even in the low resistance region – enabling reliable, high accuracy current detection. The series is qualified under the AEC-Q200 automotive reliability standard for passive components, ensuring a maximum operating temperature of 170°C that provides high reliability even in-vehicle environments where temperatures can be particularly severe, such as in the engine compartment.

Thermal simulation models for shunt resistors (including the new products) will also be available on ROHM’s website from October 2021, allowing users to perform simulations before designing the actual machine (even in high-power applications where thermal design is particularly difficult), considerably reducing design manhours.