Rapid readout circuit for resistance sensor array based on two-wire system isopotential method

Abstract

The invention discloses a rapid readout circuit for a resistance sensor array based on a two-wire system isopotential method, belonging to the technical field of sensors. Aiming at an M*N two-dimensional resistance sensor array with common row lines and column lines, the rapid readout circuit comprises a column line driving operational amplifier, a column multiplexer, a reference voltage source, M equivalent current operational amplifiers, M test current sampling resistors and two connecting lines, wherein the M equivalent current operational amplifiers are in one-to-one correspondence with M row lines of the resistance sensor array, and the two connecting lines are respectively arranged corresponding to each row line and column line of the resistance sensor array. The invention further discloses a readout method of the rapid readout circuit and a sensing system. Compared with the prior art, the rapid readout circuit has the advantages that by utilizing the two-wire system isopotential method as a key technique, measuring errors caused by the lead resistance and joint contact resistance of connecting cables and the on resistance of multi-path switch channels can be effectively eliminated, and the measurement precision of the resistance sensor array can be substantially 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] Array-type 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 features 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. [0003] Resistive sensor arrays are widely used in infrared imaging simulation systems, force tactile sensing and temperature tactile sensing. Taking temperature tactile as an example, because 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 on the accuracy and resolution of temperature measu...

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

Images