Shunt resistors developed in response to increased demand for higher rated power

Available now from Farnell element14, Rohm's PSR series of high-power shunt resistors has been developed in response to increased demand for products with higher rated power. This rise in demand has been fuelled by increasing computerisation in the automotive and industrial markets, along with the rapidly expanding current control application sector and the trend towards high current circuit designs. The PSR Series is available in the ultra-low resistance range from 0.2mO to 3mO and provides high rated power (4W, 5W), making it ideal for current detection in large-current applications. ROHM relies on special techniques to satisfy high power requirements and ensure high measurement accuracy even in the ultra-low-ohmic region (0.2mO), which requires the ability to bond copper electrodes without variations. This is achieved through ROHM's original precision welding technology to join the resistive metal to thick copper electrodes, achieving high heat capacity with exceptional thermal dissipation characteristics. This increases power-handling capability (5W class) while improving productivity. Since the temperature coefficient of resistance in metals increases as the resistance value decreases, ROHM uses a high-performance alloy material for the resistive metal, ensuring a superior temperature coefficient of resistance even at ultra-low resistances. Typical applications include Inverters, Li-ion battery maintenance and charging, DC brush motors, DC/DC conversion and AC/DC conversion.