Suitable for current detection in high-power applications in the automotive, industrial and large-scale consumer electronics sectors, ROHM has announced the development and mass production of high-power low-ohmic shunt resistors of the GMR100 series. The new shunt resistors are characterised by a high rated power of 3W and a resistance range from 5-220mΩ. Their resistance tolerance is specified with F (±1%). The temperature coefficient of resistance (TCR) is ±20ppm/°C.
The GMR100 series measures 6.4x3.2x0.4mm and the operating temperature range is between -55 and 170°C.
The increasing number of small motors and ECUs in response to the continued electronification and motorisation of automotive systems produces a greater demand for compact shunt resistors that support high-power applications. In response to this development, 2016 saw ROHM commence mass production of the PSR series, which has since become widely accepted within the industry.
To meet the demands for a wider resistance range, ROHM is now offering its GMR series with resistances from 5-220mΩ and as such much higher resistances than the PSR series.
The use of special materials and structures has allowed ROHM to successfully reduce surface temperature rise by 45% compared with conventional products. As a result, the shunts achieve stable resistance not only during normal operation but at overcurrent loads as well. In addition, the use of a high-performance alloy as the resistive metal results in excellent temperature coefficient of resistance (TCR) even in the low resistance region, which in turn ensures greater accuracy and reliability.
A special structure supports a lower profile form factor of 0.4mm, making the new GMR100 series 47% thinner than existing solutions. This provides greater scope in applications with strict temperature requirements, such as automotive systems and industrial equipment, helping to reduce design load and contribute to further end-product miniaturisation.
Application examples and availability
The GMR100 series presents a suitable solution for applications in the automotive sector such as ECUs, EPS systems, and inverters, in industrial equipment, for example in UPS, general-purpose inverters and consumer goods, such as inverters for refrigerators, air conditioning units and washing machines.