CN-122016102-A - Temperature compensation type crosstalk-proof piezoresistive sensing array acquisition circuit and control system

CN122016102ACN 122016102 ACN122016102 ACN 122016102ACN-122016102-A

Abstract

The invention relates to the field of flexible microelectronic circuits, and provides a temperature compensation type crosstalk-proof piezoresistive sensing array acquisition circuit and a control system. The acquisition circuit comprises a row driving circuit, a piezoresistive sensing array, a resistive sensing unit detection circuit, a temperature compensation voltage adder, a multiplexing circuit and a singlechip ADC acquisition module, wherein the row driving circuit is connected with a driving voltage and gates a specific row, the piezoresistive sensing array is used for performing temperature compensation on the output voltage of the row driving circuit, the resistive sensing unit detection circuit is used for enabling the output non-gated column line voltage to be kept at zero, the temperature compensation voltage adder is used for summing the temperature compensation voltage signal output by the piezoresistive sensing array and the output voltage signal of the resistive sensing unit detection circuit, the multiplexing circuit is respectively connected with the temperature compensation voltage adder and a voltage follower and is used for gating the output voltage signal of the output temperature compensation voltage adder of the specific column and performing front-back stage isolation through the voltage follower, and the inverter is used for converting the output voltage signal of the voltage follower into positive voltage and outputting the positive voltage signal to the singlechip ADC acquisition module.

Inventors

XU ZHENJIN
Shang Shoubo
GUO WENJIE
XU TONGMING
WEI CHENGLONG
Sheng tianyu
LI BOZHAO
LIN YONGWEN
YU ZHAOYANG
JING KUN
ZHAO ANRAN

Assignees

浪潮通用软件有限公司

Dates

Publication Date: 20260512
Application Date: 20260104

Claims (10)

1. A temperature compensation type crosstalk prevention piezoresistive sensing array acquisition circuit is characterized by comprising a plurality of array units, wherein each array unit is connected with an MCU through an MCU expansion array enabling module, the MCU is connected with an upper computer, and each array unit comprises: A row driving circuit which is connected with a driving voltage and gates a specific row; the piezoresistive sensing array is used for performing temperature compensation on the output voltage of the row driving circuit; a resistive sense cell detection circuit for maintaining the output non-gate column line voltage at zero; the temperature compensation voltage adder is used for summing the temperature compensation voltage signal output by the piezoresistive sensing array and the output voltage signal of the resistive sensing unit detection circuit; The multi-path selection circuit is respectively connected with the temperature compensation voltage adder and the voltage follower, and is used for gating the output voltage signal of the output temperature compensation voltage adder of a specific column and performing front-back stage isolation through the voltage follower; The inverter is used for converting an output voltage signal of the voltage follower into a positive voltage and outputting the positive voltage to the singlechip ADC acquisition module; And the singlechip ADC acquisition module is used for controlling row and column gating and data acquisition flow.
2. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 1, wherein the row driving circuit comprises a first operational amplifier, a row multiplexer and a row selection binary coding port, wherein a positive input end of the first operational amplifier is connected with a driving voltage, a negative input end and an output end of the first operational amplifier are both connected with the row multiplexer, and the row multiplexer is configured with the row selection binary coding port.
3. The temperature-compensated crosstalk-prevention piezoresistive sensor array collection circuit according to claim 1, wherein the piezoresistive sensor array comprises a plurality of temperature compensation units, each temperature compensation unit is provided with a voltage input end and a temperature compensation voltage output end and is connected through a row multiplexer, when a certain row is switched on, the voltage input ends of all the temperature compensation units in the same row are activated, and temperature compensation voltage signals output by the temperature compensation voltage output ends are transmitted to a temperature compensation voltage adder.
4. The temperature-compensated anti-crosstalk piezoresistive sensor array collection circuit according to claim 3, wherein the piezoresistive sensor array comprises one end of a fourth adjustable resistor, one end of a fifth adjustable resistor, a voltage input end of a wheatstone bridge circuit, one end of a second adjustable resistor and one end of a third adjustable resistor, the other end of the fourth adjustable resistor is connected with the other end of the second adjustable resistor and the resistive sensor unit detection circuit respectively, and the other end of the fifth adjustable resistor is connected with the other end of the third adjustable resistor and the resistive sensor unit detection circuit respectively.
5. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 4, wherein the wheatstone bridge circuit uses a temperature sensor as a temperature sensitive arm for converting a temperature signal into a differential voltage output, uses a first adjustable resistor as a reference arm for adjusting the balance of the wheatstone bridge circuit at a reference temperature, wherein a diagonal line of the wheatstone bridge circuit is connected with a positive input end and a negative input end of a second operational amplifier, an output end of the second operational amplifier is connected with a temperature compensation voltage adder, the second operational amplifier is used for amplifying the differential voltage signal output by the wheatstone bridge circuit, and two other arms of the wheatstone bridge circuit are composed of a second resistor and a third resistor.
6. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 4, wherein the output voltage of the temperature compensation unit is expressed by the following formula: Wherein K is the gain of the second operational amplifier, V i is the input voltage of the Wheatstone bridge circuit, R ref is the resistance of the first adjustable resistor, R 207 is the resistance of the second resistor, R Pt100 is the resistance of the temperature sensor, and R 208 is the resistance of the third resistor.
7. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 4, wherein the resistive sensor unit detection circuit comprises two amplifying circuits with the same structure, each amplifying circuit comprises a third operational amplifier, a fourth resistor and a fifth resistor, the negative input end of the third operational amplifier is respectively connected with the output end of the piezoresistive sensor array and one end of the fourth resistor, the positive input end of the third operational amplifier is grounded through the fifth resistor, and the other ends of the third operational amplifier and the fourth resistor are both connected with the temperature-compensated voltage adder.
8. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 1, wherein the row-column selection line of each array unit is respectively connected in parallel to the row-column strobe bus and the decoder of the MCU through the array expansion interface.
9. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 8, wherein the array expansion interface comprises a power supply pin, a ground pin, an ADC pin, an enable signal, a row selection binary coding port and a column selection binary coding port, wherein the row selection binary coding port and the column selection binary coding port are used for controlling on-off of a multiplexer, the enable port is used for controlling acquisition enabling states of an array unit by an MCU, and an ADC pin output line is also connected to an ADC bus of the MCU in parallel.
10. The temperature compensation type anti-crosstalk piezoresistive sensor array acquisition circuit control system is characterized by being applied to the temperature compensation type anti-crosstalk piezoresistive sensor array acquisition circuit disclosed in any one of claims 1-9, and comprises a temperature compensation module, an enabling module, a row-column gating module, an anti-crosstalk module, a voltage following module, a power supply module, an array expansion interface, an MCU and an upper computer, wherein the row-column gating module is respectively connected with the temperature compensation module, the anti-crosstalk module and the voltage following module, the row-column gating module is also connected with the MCU through an ADC, the MCU is connected with the array expansion interface through an enabling bus, and the MCU is also connected with the upper computer; The MCU activates a designated basic array unit through an enabling bus, then scans row by row and column by column according to a preset sequence, controls a row-column gating module, only gates one sensing unit each time, suppresses piezoresistive coupling between adjacent units through an anti-crosstalk module when collecting electric signals generated by the selected sensing units, corrects temperature drift of the electric signals through a temperature compensation module, and enters an ADC (analog to digital converter) for digital processing after the electric signals are buffered and amplified through a voltage following module, and finally the electric signals are collected by the MCU and uploaded to upper computer software to finish further data processing, analysis and visual display.

Description

Temperature compensation type crosstalk-proof piezoresistive sensing array acquisition circuit and control system Technical Field The invention relates to the technical field of flexible microelectronic circuits, in particular to a temperature compensation type crosstalk-proof piezoresistive sensing array acquisition circuit and a control system. Background The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art. The piezoresistive sensor array is widely applied to pressure distribution measurement in the fields of robot touch sensing, wearable electronic skin, medical health monitoring and the like due to the advantages of simple structure, low cost, easiness in integration and the like. However, three intractable technical challenges, spatial distributed temperature interference, crosstalk under a scanning readout architecture, and limited scalability, are always faced in the process of going to high-precision, high-reliability applications. The prior art solutions often do not address this, and it is difficult to systematically address this series of problems. First, the spatially distributed temperature interference problem is rooted in thermal field inhomogeneity of the application scenario. Although the sensor cells in the array have substantially similar temperature coefficients due to the consistency of the manufacturing process, there may be significant differences in the local micro-environment temperatures at which they are actually operated. For example, different parts of the electronic skin contact objects at different temperatures, or when operated for a long period of time, the cells in the center of the array are at a higher temperature than the edge cells due to heat build-up. This temperature gradient distribution at the same time and at different spatial locations renders the conventional global temperature compensation method based on a single temperature sensor essentially ineffective. The global compensation cannot sense the real temperature of each region in the array, and cannot provide differentiated compensation values for the sensing units in different temperature ranges. The industry is pressing to have a technology that enables "zoned" or "array element level" temperature sensing and compensation, implementing specific, differential compensation for areas affected by different temperatures, and ensuring that the compensation is within its linear range, thus achieving consistent and accurate pressure measurements across the sensing surface. Second, the crosstalk problem is inherent in high density arrays, which necessitates a "column and row scan" readout architecture for reducing the number of wires. The architecture sequentially gates each cell through a multiplexer to perform measurement, but the un-gated cells form parasitic circuit paths with shared row and column lines, and shunt or couple signals of the tested cells, so that the measured values are severely distorted. This crosstalk effect deteriorates exponentially with increasing array size, a core bottleneck that restricts array size expansion. Existing crosstalk prevention techniques, such as the equipotential shielding method, are effective but require the addition of operational amplifiers as buffers in each row or column, resulting in a linear increase in circuit complexity, power consumption, and cost with array size. Another approach, such as diode isolation, is to block cross-talk but introduce nonlinearity, increase drive voltage requirements, and severely sacrifice flexibility and stretchability of the sensor array, contrary to the trend of flexible electronics. Furthermore, limited scalability is a further bottleneck that limits the array to large-scale, high-density applications. The number of channels in a conventional acquisition system is typically fixed at the beginning of the design. To scale up the array, more analog front end chips, multiplexers, and corresponding control lines are often added, resulting in dramatic increases in system complexity, circuit board area, and cost. Meanwhile, the transmission distance of the analog signal is limited, and as the lead wire grows, the signal is more easily interfered by noise and attenuated, so that the signal integrity of the large-scale array is difficult to ensure. Most of the existing schemes adopt centralized control, all row lines and column lines are finally converged to the same control chip, so that wiring becomes extremely complex, and faults of any channel can affect the whole system. The industry lacks a standardized interface and architecture that can support modular, distributed expansion to achieve a flexible, low cost, and high performance smooth transition from small to ultra-large scale arrays. Disclosure of Invention In order to solve the technical problems in the background art, the invention provides a temperature compensation type crosstalk-proof