A CMOS TDC-based digital magnetic Hall sensor using the self temperature compensation

A CMOS TDC-based digital magnetic Hall sensor using the self temperature compensation schemes is proposed. The proposed sensor consists of the sensor device, its bias and signal-processing circuit which is fully compatible with a standard CMOS technology. For the high magnetic sensitivity, the MAGFET is implemented with proper geometric parameters. The TDC-based digital circuit is proposed for the low power consumption and easy design. The self temperature compensation schemes of mobility and threshold voltage temperature effects are utilized for the low temperature variation. The proposed sensor is implemented with a standard 0.18μm CMOS technology and shows the good detectable resolution by 0.8μT under magnetic fields ranging from 0 to 0.8T and temperature variations by 250nT ranging from −40°C to +80°C. And the very low power consumption by 360μW at 1.8V supply voltage is measured.