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 0.18 mum CMOS technology and shows the good detectable resolution by 0.8 muT under magnetic fields ranging from 0 to 0.8 T and temperature variations by 250 nT ranging from -40degC to +80degC. And the very low power consumption by 360 muW at 1.8 V supply voltage is measured.