MEMS sensor detection device and MEMS sensor system

A MEMS sensor detection device, characterized by comprising:

• a readout circuit used for analog signal processing of the output signal of the MEMS sensor to generate detection voltage;
• a cancellation voltage generation circuit used for generating a gravity cancellation voltage according to the detection voltage, wherein the gravity cancellation voltage and the gravity acceleration are in a positive proportional relationship;
• a selection circuit used for selecting the detection voltage output in a feedback phase and selecting the gravity cancellation voltage output in a gravity cancellation phase, wherein in one detection period, the feedback phase is located after the gravity cancellation phase;
• and
• a feedback circuit used for generating a feedback voltage according to the output voltage of the selection circuit, wherein the feedback voltage is in a positive proportional relationship with the output voltage of the selection circuit;
• the cancellation voltage generation circuit comprises:
• a first low-pass filter used for low-pass filtering processing of the detection voltage to generate the gravity cancellation voltage;
• a second low-pass filter used for low-pass filtering processing of the detection voltage to generate a filtered voltage;
• a pulse generator used for generating a positive pulse when the filtered voltage exceeds a preset positive voltage and generating a negative pulse when the filtered voltage exceeds a preset negative voltage;
• a counter used for counting pulses generated by the pulse generator within a preset time interval, adding 1 when the positive pulse is received, and subtracting 1 when the negative pulse is received;
• a register used for storing the counting value of the counter;
• a first digital-to-analog converter used for digital-to-analog conversion processing of the count value stored in the register so as to generate the gravity cancellation voltage.