A Highly Sensitive CMOS Digital Hall Sensor for Low Magnetic Field Applications

作者：Xu Yue; Pan Hong Bin^*; He Shu Zhuan; Li Li

来源：Sensors (Switzerland), 2012, 12(2): 2162-2174.

DOI：10.3390/s120202162

• Hall sensor
• CMOS technology
• dynamic offset cancellation
• chopped technique

Integrated CMOS Hall sensors have been widely used to measure magnetic fields. However, they are difficult to work with in a low magnetic field environment due to their low sensitivity and large offset. This paper describes a highly sensitive digital Hall sensor fabricated in 0.18 mu m high voltage CMOS technology for low field applications. The sensor consists of a switched cross-shaped Hall plate and a novel signal conditioner. It effectively eliminates offset and low frequency 1/f noise by applying a dynamic quadrature offset cancellation technique. The measured results show the optimal Hall plate achieves a high current related sensitivity of about 310 V/AT. The whole sensor has a remarkable ability to measure a minimum +/- 2 mT magnetic field and output a digital Hall signal in a wide temperature range from -40 degrees C to 120 degrees C.

• 出版日期2012-2
• 单位南京大学