Current sense resistors come with two or three pins

Current sense resistors are growing in popularity due to their high measurement accuracy and relatively low cost compared to other technologies.

This product series complements Bourns’ other circuit conditioning components, such as power inductors and rectifier diodes.

These models come with either two or three tin-plated copper pins.

Two pins are riveted to the voltage test points of the shunt resistor in order to measure the voltage drop on the resistive element, which is proportional to the current flow through the resistor.

The optional third pin connects to the ground side of the circuit. For two-pin designs, the current used by the sensor device flows through the ground side pin and causes a voltage drop between the PCB connection and the resistor, which can result in a sensing error.

Three-pin designs reduce the sensing error by carrying the ground current on a separate path from the sensing circuit.

The CSM2F series features resistance values ranging from as low as 25 µΩ up to 200 µΩ, with permanent power ratings of up to 50 W, a continuous current of up to 1,414 amps and the ability to handle high pulse power ratings.

The metal alloy current sensing element enables thermal EMF as low as 0.25 µV/K and low TCRs of ±50 PPM/°C in the +20°C to +60°C temperature range.

The resistors are AEC-Q200 compliant. They also offer excellent long-term stability and have a maximum fastening torque of 10 Nm

Applications cover battery management systems, current sensing for hybrid and electric vehicles, current sensing in bus bars and current sensing in welding equipment, as well as power modules and frequency converters.

The resistors are available from distributor Digi-Key Electronics in the Americas, EMEA and Asia-Pacific regions.