A Monolithic CMOS Magnetic Hall Sensor with High Sensitivity and Linearity Characteristics

Abstract

This paper presents a fully integrated linear Hall sensor by means of 0.8 μm high voltage complementary metal-oxide semiconductor (CMOS) technology. This monolithic Hall sensor chip features a highly sensitive horizontal switched Hall plate and an efficient signal conditioner using dynamic offset cancellation technique. An improved cross-like Hall plate achieves high magnetic sensitivity and low offset. A new spinning current modulator stabilizes the quiescent output voltage and improves the reliability of the signal conditioner. The tested results show that at the 5 V supply voltage, the maximum Hall output voltage of the monolithic Hall sensor microsystem, is up to ±2.1 V and the linearity of Hall output voltage is higher than 99% in the magnetic flux density range from ±5 mT to ±175 mT. The output equivalent residual offset is 0.48 mT and the static power consumption is 20 mW.

A Redundancy Mechanism Design for Hall-Based Electronic Current Transformers

“…Generally, sensing materials of the commercial Hall sensors are mainly InSb, InAS, GaAs, Ge, and Si, and InSb, and GaAs demonstrates the best performance. Also, regarding the Si-based Hall sensor, the integrated circuit with built-in compensation circuits can reduce output noise and strengthen sensitivity [21]. Hence, Si becomes a widely used material for Hall sensors.…”

Hall Effect Modeling in FEM Simulators and Comparison to Experimental Results in Silicon and Printed Sensors

“…Current literature suggests that using contacts that cover the entirety of the sensors' edges are better for eliminating offset issues [39]. This might occur because the contact "averages" the voltage perceived at the edges of the sensor as opposed to multiple-point contacts from alligator clips.…”

“…Contemporary literature on Hall effect devices seems to favor cross-shaped sensors [7], [39]. However, with more complex sensors and devices being researched and fabricated each day, simulations, such as the ones developed in this thesis, can be powerful tools for IC designers since it allows tuning of material properties and geometry for the theoretical device under investigation.…”

“…A possible solution is presented in [3], which claims that temperature drift can be fixed by the means of a temperature compensation circuit that heats up the hall device by [39]. The low-frequency content from the adder contains the Hall signal, which is then passed through a filter to eliminate high-frequency noise.…”

“…This step finishes the Hall device on the silicon wafer. However, metal contacts are required across the edges of the sensor to reduce offset [39] in the case of the cross-shaped structures and to facilitate sensor operation and measurements.…”