Low Power CMOS-Based Hall Sensor with Simple Structure Using Double-Sampling Delta-Sigma ADC

Juyong Lee; Younggyun Oh; Sein Oh; Hyungil Chae

doi:10.3390/s20185285

Low Power CMOS-Based Hall Sensor with Simple Structure Using Double-Sampling Delta-Sigma ADC

Sensors (Basel). 2020 Sep 16;20(18):5285. doi: 10.3390/s20185285.

Authors

Juyong Lee¹, Younggyun Oh², Sein Oh², Hyungil Chae¹

Affiliations

¹ Department of Electrical and Electronic Engineering, Konkuk University, Seoul 05029, Korea.
² Department of Electrical and Electronic Engineering, Kookmin University, Seoul 02707, Korea.

Abstract

A CMOS (Complementary metal-oxide-semiconductor) Hall sensor with low power consumption and simple structure is introduced. The tiny magnetic signal from Hall device could be detected by a high-resolution delta-sigma ADC in presence of offset and flickering noise. Also, the offset as well as the flickering noise are effectively suppressed by the current spinning technique combined with double sampling switches of the ADC. The double sampling scheme of the ADC reduces the operating frequency and helps to reduce the power consumption. The prototype Hall sensor is fabricated in a 0.18-µm CMOS process, and the measurement shows detection range of ±150 mT and sensitivity of 110 µV/mT. The size of active area is 0.7 mm², and the total power consumption is 4.9 mW. The proposed system is advantageous not only for low power consumption, but also for small sensor size due to its simplicity.

Keywords: delta-sigma ADC; double sampling; hall sensor; horizontal hall device; magnetic sensor.

Publication types

Letter

Grants and funding

2018R1D1A1B07048794/National Research Foundation of Korea/International