Suppression of Temperature Drift in Tunneling Magnetoresistance Current Sensors by Digital-Analog Hybrid Compensation

Tunneling magnetoresistance (TMR) current sensors have been studied extensively in recent years due to their advantages of high sensitivity and low power consumption. However, temperature drift remains a critical factor limiting their detection accuracy and stability. Here we propose a digital-analog hybrid compensation scheme for temperature drift suppression and demonstrate a high-precision TMR current sensor prototype. Experimental verification shows that after compensation, the sensor achieves a sensitivity temperature drift of 17.18 ppm/°C and a zero-point temperature drift of 9.86 ppm/°C within the temperature range of −40°C to +80°C. Simultaneously, the TMR sensor features a working bandwidth of DC-80 kHz, with a full-scale error not exceeding 0.5%FS within the measurement range of ±10 Ap, a minimum resolution of 2 mA, and a dynamic range as high as 80 dB. The proposed digital-analog hybrid compensation method provides an important guidance for the design and application of TMR sensors with suppressed temperature drift.