An asic interface for capacitive angular displacement sensor

Abstract

The invention relates to an ASIC interface applied to a capacitive grating angular displacement sensor. The ASIC interface comprises a direct current capacitance compensation array, a C-V converter, aresonator, a quantizer, a capacitance feedback array under the control of a digital signal, and a digital demodulation filtering module; the direct current capacitance compensation array is used forcounteracting a direct current amount C0 in a capacitor; the C-V converter is used for converting a detection capacitance signal into a proportionable voltage signal via C-V conversion; the resonatoris used for performing band-pass sigma-delta modulation on a voltage signal output by the C-V converter; the quantizer is used for converting a signal output by the resonator into a bit stream signal;the capacitance feedback array under the control of the digital signal is used for adjusting the dynamic range of the input signal of the C-V converter according to the bit stream signal output by the quantizer; and the digital demodulation filtering circuit is used for performing digital demodulation on the bit stream signal output by the quantizer to output the digital quantity of the measurement signal of the sensor.

Description

technical field [0001] The invention relates to an ASIC (Application Specific Integrated Circuit) interface for a capacitive angular displacement sensor, and relates to the technical field of sensing. Background technique [0002] Capacitive angular displacement sensors are widely used. With the rapid development of technologies such as autonomous navigation micro-terminals, small unmanned boats, various drones, and robots in recent years, the annual demand for ultra-small angle sensors in these applications is in the millions Above all, ordinary angle sensors are difficult to meet the urgent needs of these applications in terms of size, cost and power consumption. Therefore, the miniature low-cost high-precision capacitive angle sensor has great market development prospects, mainly including: 1) for unmanned Angle measurement of machine, small robot, and high-precision stable platform, which significantly reduces volume, power consumption, and cost, and can replace various ...

AI Technical Summary

Problems solved by technology

[0007] But in practice because C 0 During the C-V conversion, a large part of the voltage of the power supply is applied to the C which is meaningless to improve the measurement accuracy. 0 In general, high power supply voltage is required to achieve high capacitance resolution. The size of a general micro-capacitive sensor is about 15mm, and the detection capacitance is on the order of 0.5pf. It is difficult for general separation devices to achieve small volume and low Realize high-precision measurement under the condition of low power consumption; in addition, the current measurement methods all adopt the working mode of DC ADC sampling, which is very sensitive to the noise of low-frequency sensors, and it is difficult to achieve high-precision measurement

Images