CMOS magnetic sensor arrays using native-substrate MAGFETs for a smart rotary encoder

In CMOS-based smart sensors, it is particularly important for the sensor´s high performance to be compatible with advanced CMOS technology. The paper introduces a split-drain MAGFET with a native substrate structure that can improve the signal-to-offset deviation ratio by a factor of four compared with that of a normal MAGFET made on a p-well substrate. The native type MAGFET is incorporated into a CMOS rotary encoder based on magnetic sensor arrays, and the resulting angle detection accuracy is improved by a factor of three when compared to the conventional structure. As a result, the proposed technology is an effective way to fabricate a low-cost and high-performance sensor chip.