In the automotive and industrial equipment fields, current sensing circuits are essential for applications such as current feedback, overcurrent limitation, and battery level monitoring. The shunt-based current sensing circuit is the most standard circuit for current measurement and monitoring. ROHM provides solutions that leverage the resistor technology it has developed since its founding, as well as the analog and thermal design technologies it has cultivated over many years, contributing to improved system performance, higher power efficiency, and higher reliability through high-precision current sensing.

The components you select will vary depending on the power supply system and detection current value. We have a lineup of reference designs for 12V, 24V, and 48V systems, as well as current sensing values from 20 to 100A. We publish not only the schematic design guide but also thermal evaluation data for shunt resistors. Thermal issues are an important factor in shunt-based current sensing. Please use these as design references to help reduce design man-hours.

This reference design is designed for 20A, uni-direction current sensing on 12V systems.