Resistive sensor array readout circuit based on two-wire system equipotential method

Abstract

The invention discloses a resistive sensor array readout circuit based on a two-wire system equipotential method, and belongs to the technical field of sensors. The readout circuit aims at an M * N two-dimensional resistive sensor array sharing a row line and a column line. The readout circuit comprises a current feedback operational amplifier, a column line driving operational amplifier, a row multiplexer, a column multiplexer, a test current setting resistor, a reference voltage source and two connecting lines which are respectively arranged for each row line and each column line of the resistive sensor array. The invention further discloses a readout method of the readout circuit, and a sensing system. The two-wire system equipotential method is taken as a key technology, so measurementerrors caused by connecting cable lead resistance, cable joint contact resistance and multi-way switch channel conduction resistance can be effectively eliminated, and the measurement precision of the resistive sensor array is greatly improved.

Description

technical field [0001] The invention relates to the technical field of sensors, in particular to a resistive sensor array readout circuit. Background technique [0002] The array sensing device is to combine multiple sensing elements with the same performance according to the structure of a two-dimensional array. It can change or generate corresponding shapes and characteristics by detecting changes in parameters focused on the array. This feature is widely used in biosensing, temperature tactile and thermal imaging based on infrared sensors, etc. [0003] Resistive sensor arrays are widely used in infrared imaging simulation systems, force tactile sensing and temperature tactile sensing. Taking temperature touch as an example, since the temperature sensing device involves the transfer of heat and the perception of temperature, in order to obtain the thermal properties of the object, the device puts forward higher requirements for the temperature measurement accuracy and re...

AI Technical Summary

Problems solved by technology

Lead resistances with basically the same resistance and contact resistances with different resistances have a significant impact on the test accuracy of the resistive sensor array

As far as the shared row and column resistive sensor array based on the equipotential method is concerned, the lead resistance and contact resistance cause the potential difference between the drive terminal of the readout circuit and the drive terminal of the resistive sensor array module, and also cause the The potential difference between the sampling terminal of the resistive sensor array module, thus destroying the ideal isolation feedback condition of the readout circuit, and making the resistance measurement error of the unit under test larger

Therefore, basically the same lead resistance and different joint contact resistance have a significant impact on the test results of the shared row and column resistive sensor array based on the equipotential method. At the same time, the channel conduction resistance of the multi-way switch in the traditional method will affect the unit under test. How to eliminate the influence of these factors is a problem to be further studied

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