Product Family

CUR 423x

TMR-Based Closed-Loop Sensor for High-Current Coreless Applications

 

The CUR 423x is a single-axis contactless magnetic-field sensor for galvanically isolated DC and AC current measurements. The Tunnel Magneto Resistance (TMR) sensing technology enables current measurements with high sensitivity and high accuracy in high-power applications. The galvanically isolated power and sensing circuits are of particular benefit in high-voltage battery monitoring systems of hybrid and electric vehicles (xEV). A very good signal-to-noise ratio and a total error below 1% (full scale) over temperature allow precise current measurements in applications with a signal bandwidth of up to 5 kHz.


All the necessary components for a closed-loop circuit, such as compensation coil, RSHUNT, and TMR sensor bridge, are integrated into a small 1 mm thin industry standard TSSOP16 SMD package. By avoiding the need for a large magnetic-field concentrator core, space and costs can be saved. Digital offset and gain temperature compensation, low-pass filter, and clamping can easily be programmed by using TDK-Micronas’ programming toolchain.


Two variants are available that offer magnetic flux density ranges of either +-7 mT or +-40 mT. A programmable fine adjustment of the field ranges allows an adaptation to different application current ranges.

Current sensing modules equipped with the CUR 423x can be programmed via the output pin during the manufacturing process. Customer-selectable output interfaces, like SENT acc. to SAEJ2716 Rev.4, SPI or full ratiometric analog, allow a flexible adaptation to application requirements.

The CUR 423x is developed according to ISO26262 ASIL-B ready. The device is qualified according to AEC-Q100-Rev-H and is designed for automotive applications with temperatures ranging from –40 °C to +170 °C (TJ).

Block diagram of the CUR 423x

https://www.micronas.com/sites/default/files/svg/CUR423y_block_diagram.svgBlock diagram of the CUR 423x