ROHM has developed ultrathin metal plate shunt resistors for high power applications in vehicle-mounted and industrial equipment

     ROHM, the world's leading semiconductor manufacturer, has developed the industry's ultra-thin metal-plate shunt resistor "PSR350" with a rated power of 12W for high-power applications in vehicular and industrial equipment. In addition, ROHM plans to introduce 0.2mΩ PSR330 and PSR100, which have already reached the lowest level in the industry among 15W rated products, to further enhance the PSR lineup.

     In the power module of industrial equipment, the product of built-in shunt resistor has already appeared. In recent years, in the main drive inverters of xEV, in order to reduce the size of the shell, thin power modules equipped with heat dissipation mechanisms on both sides of the module are gradually increasing, and the demand for built-in shunt resistor is also increasing. However, the thickness of previous metal shunt resistors may affect the heat dissipation efficiency of power devices. In addition, to reduce the thickness of the shunt resistor, a variety of welding materials need to be tested and evaluated. ROHM is able to test various welding materials in small batches, taking advantage of a vertically integrated production system. Through the flexible development system actively responding to the market demand, the industry's ultra-thin power shunt resistor has been successfully developed.

     The PSR350 takes advantage of ROHM's vertically integrated production system and optimizes materials and manufacturing processes to achieve a 0.85mm ultra-thin package at 12W rated power, which is about half the height of previous products. More and more products such as vehicle main drive inverters are starting to use double-sided cooling power modules, and ROHM's new products make it possible to have built-in power device chips (IGBT or SiC MOSFET) and power shunt resistors, which will contribute to the miniaturization development of main drive inverters.

     Like the PSR350, the PSR330 is expected to achieve the industry's ultra-small 6464 size (6.4mm×6.4mm) with 15W rated power, which is about 65% smaller than previous products with the same rated power. Therefore, it is very helpful to reduce the installation area of various high-power applications. At the same time, ROHM plans to extend the lower limit of the PSR100 from 0.3mΩ to 0.2mΩ and introduce new products to support higher current detection applications.

     The PSR series is ROHM's highest range of metal plate shunt resistor, in the ever-increasing power of vehicle equipment and industrial equipment application consulting day by day. Often, there is a trade-off between the rated power of a resistor and the size of the product, and it is generally considered difficult to ensure that both values meet demand. ROHM's advantage lies in its vertically integrated production system, which can shorten the development cycle through small batch trial production. Materials and manufacturing processes have been optimized to achieve a high power rating at a small size. Not only that, but the resistance temperature coefficient of the new product is significantly lower than that of the conventional product with the same power rating, which will contribute to the miniaturization and reliability of the application product.