Fast readout circuit of resistive sensor array based on two-wire system isopotential method

Abstract

The invention discloses a fast readout circuit of a resistive sensor array based on a two-wire system isopotential method, and belongs to the technical field of sensors. For an M*N two-dimensional resistive sensor array that shares row and column lines, the fast readout circuit comprises a column line driving operational amplifier, a column multiplexer, a reference voltage source, M equivalent-current operational amplifiers and M test current sampling resistors which one-to-one correspond to M row lines of the resistive sensor array, and two connection lines respectively provided for each rowline and column line of the resistive sensor array. The invention further discloses a readout method of the above fast readout circuit and a sensing system. Compared with the prior art, in the fast readout circuit of the resistive sensor array based on the two-wire system isopotential method disclosed by the invention, the two-wire system isopotential method is adopted as a key technology, measurement errors generated by a connection cable lead resistance, a cable connector contact resistance and a multiple-switch channel on-resistance can be effectively eliminated, and the measurement accuracy 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 fast readout circuit of a resistive sensor array. 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 accur...

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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