A sensor chip includes sensor pads, and the first set of differential detection signal pads are symmetrically arranged on both sides of a ground pad and are centered at the ground pad, the second set of differential detection signal pads are arranged on both sides thereof, and a power supply pad is arranged in one end of the two ends of the sensor pads. A processing circuit chip includes sensor connection pads including power supply connection pads, a ground connection pad, and two sets of differential detection signal connection pads, and the power supply connection pads connectable to the power supply pad of the sensor chip are arranged in two ends of the sensor connection pads.