Metal plate shunt resistor is double-sided cooled for automotive use
A low profile, 12W metal plate shunt resistor is designed for double-sided cooled power modules in automotive and industrial equipment applications by Rohm Semiconductor.
The company claimed that one of the resistors, the PSR350 is the industry’s thinnest, measuring 0.03inch or 0.85mm in height. The 12W rated metal plate shunt resistor is optimised for high power applications in the automotive and industrial equipment markets. Rohm will expand the PSR range to include a 0.2 mOhm (PSR100) model and a 15W type in the industry’s smallest size (PSR330).
The PSR350 uses Rohm’s vertically integrated production system together with material and process optimisation to achieve a thickness of just 0.03inch (0.85mm), about half that of conventional products in the 12W class. The same technology is used to develop the smallest size (0.25inch × 0.25inch / 6.4mm × 6.4mm) 15W rated shunt resistor in the industry (PSR330). This decreases size by about 65% compared to conventional products in the same class, helping to reduce mounting area in a wide range of high power applications. At the same time, the PSR100 will be available in a 0.2mΩ model that extends the lower limit from the existing 0.3mΩ to enable detection of even higher currents.
The new products are suitable for high current sensing in applications equipped with motors and / or li-ion batteries. Target applications in automotive designs include electronic power steering (EPS), electric compressors, main inverters, on board charger (OBC), DC/DC and battery management systems (BMS).
It can also be used in industrial equipment, for example power modules, power tools, PV inverters, server power supplies, uninterruptible power supplies and base station power supplies.
For consumer devices, it can be used in home appliances, such as air conditioners, refrigerators, vacuum cleaners and washing machines.
Shunt resistors have been used in power modules for industrial equipment for some time. Conventional metal plate shunt resistors reduce the cooling efficiency of power devices due to their relatively high profile but decreasing height has proven difficult, as it is necessary to prototype and evaluate a variety of welding materials in different configurations. Rohm manufactures and designs short run prototypes for a range of welding materials and patterns.
