Test circuit for resistive sensor array based on two-wire system isopotential method

Abstract

The invention discloses a test circuit for a resistive sensor array based on a two-wire system isopotential method, and belongs to the technical field of sensors. The test circuit aims at the M*N 2D resistive sensor array in which row and column lines are shared; and the test circuit comprises a current feedback operation amplifier, N column line driving operation amplifiers, an equal current M-to-1 multipath switch, an isopotential M-to-1 multipath switch, N column line 2-to-1 multipath switch, a test current setting resistor, a reference voltage source and two connecting wires, and the connecting wires is used for the row lines and the column lines of the resistive sensor array. The invention also discloses a test method of the test circuit and a sensing system. Compared with the prior art, the test circuit uses the two-wire system isopotential method as key technology, measuring errors caused by lead resistance of connecting cables, contact resistance of cable joints and conduction resistance of multipath switch channels can be eliminated effectively, and the measuring 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 testing 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 lead to the potential difference between the test circuit driving terminal and the resistive sensor array module driving terminal, and also cause the test circuit sampling terminal to resist. The potential difference between the sampling terminals of the sensor array module destroys the ideal isolation feedback condition of the test circuit and increases the resistance measurement error of the unit under test.

Therefore, basically the same connection cable lead resistance and different cable 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. Affects the measurement error of the unit under test, how to eliminate the influence of these factors is a problem that needs further study

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