Temperature compensation type anti-crosstalk piezoresistive sensing array acquisition circuit and control system

Abstract

The invention relates to the field of flexible microelectronic circuits, and provides a temperature compensation type anti-crosstalk piezoresistive sensor array acquisition circuit and a control system. The acquisition circuit 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; the resistive sensing unit detection circuit is used for keeping the output non-gating column line voltage at zero; the temperature compensation voltage adder is used for summing a temperature compensation voltage signal output by the piezoresistive sensing array and an output voltage signal of the resistive sensing unit detection circuit; the multipath selection circuit is respectively connected with the temperature compensation voltage adders and the voltage follower, and the multipath selection circuit is used for gating output voltage signals of the output temperature compensation voltage adders of a specific column and carrying out front and back stage isolation through the voltage follower; and the phase inverter is used for converting the output voltage signal of the voltage follower into positive voltage and outputting the positive voltage to the singlechip ADC acquisition module.

Description

Technical Field

[0001] This invention relates to the field of flexible microelectronic circuit technology, and in particular to a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit and control system. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Piezoresistive sensor arrays are widely used for pressure distribution measurement in fields such as robotic tactile sensing, wearable electronic skin, and medical health monitoring due to their advantages of simple structure, low cost, and ease of integration. However, in the process of achieving high-precision and high-reliability applications, they consistently face three major persistent technical challenges: spatially distributed temperature interference, crosstalk in scanning readout architectures, and limited scalability. Existing technical solutions often address one aspect at the expense of another, making it difficult to systematically solve these problems. First, the root cause of spatially distributed temperature interference lies in the non-uniformity of the thermal field in the application scenario. Although the temperature coefficients of the sensing units in the array are basically similar due to the consistency of the manufacturing process, the local microenvironment temperature they are in during actual operation may vary significantly. For example, different parts of the electronic skin may come into contact with objects of different temperatures; or during long-term operation, the unit located in the center of the array may be hotter than the edge units due to heat accumulation. This temperature gradient distribution at the same time but different spatial locations renders traditional global temperature compensation methods based on a single temperature sensor essentially ineffective. Global compensation cannot sense the true temperature of each region in the array, let alone provide differentiated compensation values ​​for sensing units located in different temperature ranges. The industry urgently needs a technology that can perform "regional" or "array-level" temperature sensing and compensation, implementing specific and differentiated compensation for areas affected by different temperatures, and ensuring that the compensation is within its linear range, thereby achieving consistent and accurate pressure measurement across the entire sensing surface.

[0004] Secondly, crosstalk is inherent in high-density arrays, which inevitably employ a "row-column scanning" readout architecture to reduce leads. This architecture sequentially selects each cell for measurement using a multiplexer, but unselected cells form parasitic circuit paths with shared row and column lines, causing signal shunting or coupling to the measured cell and resulting in severe measurement distortion. This crosstalk effect worsens exponentially with increasing array size, becoming a core bottleneck restricting array scaling. Existing anti-crosstalk technologies, such as equipotential shielding, are effective but require adding operational amplifiers as buffers in each row or column, leading to a linear increase in circuit complexity, power consumption, and cost with array size. Another approach, such as diode isolation, blocks crosstalk but introduces nonlinearity, increases drive voltage requirements, and severely sacrifices the flexibility and stretchability of the sensor array, contradicting the trend towards flexible electronics.

[0005] Furthermore, limited scalability is another bottleneck restricting the large-scale, high-density application of arrays. Traditional acquisition systems typically have a fixed number of channels from the initial design stage. Expanding the array size often requires adding more analog front-end chips, multiplexers, and corresponding control circuitry, leading to a sharp increase in system complexity, board area, and cost. Simultaneously, the transmission distance of analog signals is limited, and as the lead length increases, the signal becomes more susceptible to noise interference and attenuation, making it difficult to guarantee signal integrity in large-scale arrays. Most existing solutions employ centralized control, with all rows and columns ultimately converging on the same control chip, making wiring extremely complex, and the failure of any one channel can affect the entire system. The industry lacks a standardized interface and architecture that supports modular, distributed expansion to achieve a flexible, low-cost, and high-performance smooth transition from small- to medium-scale arrays. Summary of the Invention

[0006] To address the technical problems mentioned above, this invention provides a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit and control system. The acquisition circuit of this invention can deeply integrate array element-level fine temperature compensation, efficient and low-cost crosstalk suppression, and modular seamless expansion capabilities, truly unleashing the application potential of piezoresistive sensor arrays in high-precision measurement and large-scale sensing; it is suitable for high-precision, multi-channel, and scalable piezoresistive sensor array signal acquisition systems.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit.

[0008] A temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit includes: several array units, each array unit being connected to an MCU via an MCU array enable module, and the MCU being connected to a host computer; each array unit includes: The row drive circuit is connected to the drive voltage and selects a specific row; Piezoresistive sensor arrays are used for temperature compensation of the output voltage of the row drive circuit. The resistive sensing unit detection circuit is used to keep the output non-gated column line voltage zero; A temperature-compensated voltage adder is used to sum the temperature-compensated voltage signal output by the piezoresistive sensor array and the output voltage signal of the resistive sensing unit detection circuit. The multiplexing circuit is connected to the temperature-compensated voltage adder and the voltage follower respectively. The multiplexing circuit is used to select the output voltage signal of the temperature-compensated voltage adder in a specific column and isolates the output from the front and rear stages through the voltage follower. An inverter is used to convert the output voltage signal of a voltage follower into a positive voltage and output it to the microcontroller's ADC acquisition module. The microcontroller ADC acquisition module is used to control the row and column gating and data acquisition process.

[0009] Furthermore, the row driving circuit includes: a first operational amplifier, a row multiplexer, and a row selection binary encoding port. The positive input terminal of the first operational amplifier is connected to a driving voltage, and both the negative input terminal and the output terminal of the first operational amplifier are connected to the row multiplexer. The row multiplexer is configured with a row selection binary encoding port.

[0010] Furthermore, the piezoresistive sensing array includes several temperature compensation units, each of which has a voltage input terminal and a temperature compensation voltage output terminal, and is connected through a row multiplexer; when a certain row is selected, the voltage input terminals of all temperature compensation units in the same row are activated, and the temperature compensation voltage signal output by the temperature compensation voltage output terminal is transmitted to the temperature compensation voltage adder.

[0011] Furthermore, the piezoresistive sensing array includes one end of a fourth adjustable resistor connected to the output of the row drive circuit, one end of a fifth adjustable resistor, the voltage input terminal of the 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 to the other end of the second adjustable resistor and the resistive sensing unit detection circuit, respectively. The other end of the fifth adjustable resistor is connected to the other end of the third adjustable resistor and the resistive sensing unit detection circuit, respectively.

[0012] Furthermore, the Wheatstone bridge circuit uses a temperature sensor as the temperature-sensitive arm to convert the temperature signal into a differential voltage output; it uses a first adjustable resistor as the reference arm to adjust the balance of the Wheatstone bridge circuit at a reference temperature; the diagonal of the Wheatstone bridge circuit is connected to the positive and negative input terminals of the second operational amplifier, the output terminal of the second operational amplifier is connected to a temperature-compensated voltage adder, the second operational amplifier is used to amplify the differential voltage signal output by the Wheatstone bridge circuit, and the other two arms of the Wheatstone bridge circuit are composed of a second resistor and a third resistor.

[0013] Furthermore, the output voltage of the temperature compensation unit is expressed by the following formula:

[0014] in, K V is the gain of the second operational amplifier. i R represents the input voltage of the Wheatstone bridge circuit. ref R represents the resistance value of the first adjustable resistor. 207 R represents the resistance value of the second resistor. Pt100 R represents the resistance value of the temperature sensor. 208 This indicates the resistance value of the third resistor.

[0015] Furthermore, the resistive sensing unit detection circuit includes two identical amplifier circuits. Each amplifier circuit includes a third operational amplifier, a fourth resistor, and a fifth resistor. The negative input terminal of the third operational amplifier is connected to the output terminal of the piezoresistive sensing array and one end of the fourth resistor, respectively. The positive input terminal of the third operational amplifier is grounded through the fifth resistor. The output terminal of the third operational amplifier and the other end of the fourth resistor are both connected to a temperature-compensated voltage adder.

[0016] Furthermore, the row and column selection lines of each array unit are connected in parallel to the MCU's row and column gating bus and decoder through the array expansion interface.

[0017] Furthermore, the array expansion interface includes: a power supply pin, a ground pin, an ADC pin, an enable signal, a row selection binary encoding port, and a column selection binary encoding port; the row selection binary encoding port and the column selection binary encoding port are used to control the on / off state of the multiplexer; the enable port is used for the MCU to control the acquisition enable state of the array unit; the ADC pin output line is also connected in parallel to the MCU's ADC bus.

[0018] A second aspect of the present invention provides a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit control system.

[0019] A temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit control system is applied to the temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit described in the first aspect above, comprising: a temperature compensation module, an enable module, a row and column gating module, an anti-crosstalk module, a voltage follower module, a power supply module, an array expansion interface, an MCU, and a host computer. The row and column gating module is connected to the temperature compensation module, the anti-crosstalk module, and the voltage follower module, respectively. The row and column gating module is also connected to the MCU via an ADC. The MCU is connected to the array expansion interface via an enable bus. The MCU is also connected to the host computer. The MCU activates the designated base array cells through the enable bus, and then scans them row by row and column by column in a predetermined order, controlling the row and column gating module to select only one sensing cell at a time. When acquiring the electrical signal generated by the selected sensing cell, the anti-crosstalk module suppresses the piezoresistive coupling between adjacent cells, and then the temperature compensation module corrects its temperature drift. The signal is buffered and amplified by the voltage follower module and then enters the ADC for digital processing. Finally, the MCU collects and uploads the data to the host computer software to complete further data processing, analysis and visualization.

[0020] Compared with the prior art, the beneficial effects of the present invention are: This invention effectively improves the accuracy, scale, and reliability of piezoresistive sensor array applications. Firstly, by using four piezoresistive elements as a group and incorporating a Wheatstone bridge temperature compensation unit, it achieves a leap from coarse global compensation to precise element-level local compensation. This design can sense and respond in real-time to changes in the spatially distributed temperature gradient on the array surface, performing independent and differentiated compensation calibration for elements in different temperature regions. This solves the overall measurement error problem caused by thermal field inhomogeneity, minimizing the impact of temperature drift, and thus ensuring the accuracy and consistency of the entire array measurement data even in complex thermal environments.

[0021] This invention utilizes the "virtual short" characteristic of operational amplifiers to forcibly clamp the potential of the non-gated column lines to zero, cutting off the parasitic path of crosstalk current. This active suppression strategy eliminates the need for redundant voltage followers for each row and column, and avoids introducing diode components that would compromise the flexibility. While reducing cost and complexity, it achieves excellent crosstalk suppression, improves the system's signal-to-noise ratio and anti-interference capability, and especially ensures the detection accuracy of minute pressure signals.

[0022] The standardized array expansion interface architecture proposed in this invention liberates the system from rigid centralized control to a flexible, modular, distributed organization. Based on a 64-unit expansion module, a unified digital interface and enable control enable plug-and-play seamless expansion of large-scale arrays. This design simplifies system wiring, reduces the marginal cost of channel expansion, and effectively avoids the attenuation and interference problems of long-distance analog signal transmission, making it possible and easy to construct ultra-high-density arrays with thousands or even larger sensing units. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] Figure 1 This is a circuit diagram of a single array unit of a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit shown in an embodiment of the present invention. Figure 2 This is a schematic diagram of the layout structure of a piezoresistive sensing array shown in an embodiment of the present invention; Figure 3 This is a Wheatstone bridge circuit diagram inside the temperature compensation unit shown in an embodiment of the present invention; Figure 4 This is a circuit diagram of the internal circuit of a 2×2 piezoresistive sensor array shown in an embodiment of the present invention; Figure 5 This is a schematic diagram of the pin definition of the array element expansion interface shown in an embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the extended connection of an MCU controlling four 8×8 array units via a 2-4 decoder 901, as shown in an embodiment of the present invention. Figure 7 This is a framework diagram of a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit control system shown in an embodiment of the present invention; The system comprises: 1. Horizontal drive circuit; 101. First operational amplifier; 102. Horizontal multiplexer; 103. Horizontal selection binary encoding port; 104. First resistor; 2. Piezoresistive sensor array; 201. Temperature compensation unit; 202. Voltage input terminal; 203. Compensation circuit; 204. Temperature sensor; 205. First adjustable resistor; 206. Second operational amplifier; 207. Second resistor; 208. Third resistor; 209. Second adjustable resistor; 210. Third adjustable resistor; 211. Fourth adjustable resistor; 212. Fifth adjustable resistor; 3. Resistive sensing unit detection circuit. 301. Third operational amplifier; 302. Fourth resistor; 303. Fifth resistor; 4. Temperature-compensated voltage adder; 401. Fourth operational amplifier; 402. Sixth resistor; 403. Seventh resistor; 5. Column multiplexer circuit; 501. Column multiplexer; 502. Column selection binary encoding port; 6. Voltage follower; 7. Inverter; 701. Eighth resistor; 702. Ninth resistor; 703. Fifth operational amplifier; 704. Tenth resistor; 8. Microcontroller ADC acquisition module; 901. 2-to-4 decoder; 902. Array expansion interface; 10. Row and column selection bus. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0026] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0027] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0028] As described in the background section, existing piezoresistive sensor arrays suffer from three main problems in application: First, temperature drift leads to measurement errors, especially when different sensor units have the same temperature characteristics but experience different temperature variation regions, making it difficult to achieve differentiated compensation for temperature-affected areas; second, crosstalk during row and column scanning severely affects the accuracy of small signal detection; and third, existing systems have poor scalability, making it difficult to achieve flexible networking and acquisition of large-scale arrays. To address at least one of these technical problems, this invention provides a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit and method. The following describes the solution in detail through several embodiments.

[0029] The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit described in this embodiment includes several array units with the same structure. Each array unit is connected to a 2-4 decoder 901 through an array expansion interface 902. The array expansion interface 902 is connected to an MCU through a row and column strobe bus 10. The MCU is connected to a host computer.

[0030] Figure 1 This is a circuit diagram of a single array unit of a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit shown in an embodiment of the present invention; refer to Figure 1 The system includes: a row drive circuit 1, a piezoresistive sensor array 2, a resistive sensing unit detection circuit 3, a temperature-compensated voltage adder 4, a column multiplexer circuit 5, a voltage follower 6, an inverter 7, and an ADC acquisition module 8. The row drive circuit 1 is connected to the piezoresistive sensor array 2. The piezoresistive sensor array 2 is connected to the resistive sensing unit detection circuit 3. The resistive sensing unit detection circuit 3 is connected to the temperature-compensated voltage adder 4. The temperature-compensated voltage adder 4 is connected to the column multiplexer circuit 5. The column multiplexer circuit 5 is connected to the voltage follower 6. The voltage follower 6 is connected to the inverter 7. The inverter 7 is connected to the microcontroller ADC acquisition module 8. The column multiplexer circuit 5 includes a column multiplexer 501 and a column selection binary encoding port 502.

[0031] Specifically, the row driving circuit of a single array unit includes: a first operational amplifier 101 and a row multiplexer 102, which selects a specific row through the row selection binary encoding port 103; the piezoresistive sensing array 2 uses 2×2 as a basic array element, and each array element integrates a temperature compensation unit 201 in the center; the resistive sensing unit detection circuit 3 uses the virtual short characteristic of the third operational amplifier 301 to keep the voltage of the non-selected column line zero, effectively suppressing crosstalk; the temperature compensation voltage adder 4 is used to summarize the pressure signal and the temperature compensation signal; the column multiplexer circuit 5 and the voltage follower 6 work together to eliminate the influence of the internal resistance of the multiplexer on the detection result; the inverter 7 converts the signal into a positive voltage output and connects it to the port of the microcontroller ADC acquisition module 8; the microcontroller ADC acquisition module 8 controls the row and column selection and data acquisition process through the IO port.

[0032] This embodiment utilizes the "virtual short" characteristic of operational amplifiers to forcibly clamp the potential of the non-gated column lines to zero, cutting off the parasitic path of crosstalk current. This active suppression strategy eliminates the need for redundant voltage followers for each row and column, and avoids introducing diode components that would compromise the flexibility. While reducing cost and complexity, it achieves excellent crosstalk suppression, improves the system's signal-to-noise ratio and anti-interference capability, and especially ensures the detection accuracy of minute pressure signals.

[0033] Figure 2 This is a schematic diagram of the layout structure of a piezoresistive sensing array shown in an embodiment of the present invention; see reference. Figure 2 The diagram clearly illustrates the organization of a 2×2 piezoresistive sensing array, comprising several temperature compensation units 201. Each temperature compensation unit 201 has a voltage input terminal and a temperature compensation voltage output terminal, connected via a row multiplexer 102. When a row is selected, the voltage input terminals 202 of all temperature compensation units 201 in the same row are activated. The column multiplexer selects a specific temperature sensing unit, and its output temperature compensation voltage is transmitted to the temperature compensation voltage adder 4 via the compensation line 203, achieving real-time temperature compensation for the selected array element in that row.

[0034] Figure 3 This is a schematic diagram of the Wheatstone bridge circuit inside the temperature compensation unit shown in an embodiment of the present invention; see reference. Figure 3 This Wheatstone bridge circuit uses a Pt100 temperature sensor 204 as the temperature-sensitive arm, utilizing its resistance value to linearly change with temperature to convert the temperature signal into a differential voltage output. A first adjustable resistor 205 (R) is provided on the reference arm of the bridge. ref ), used to adjust the bridge balance at a reference temperature. Power supply (V i The voltage input terminal 202 provides the required operating voltage to the bridge. The diagonal of the bridge is connected to the second operational amplifier 206, which amplifies the differential voltage signal output by the bridge, thereby improving signal acquisition accuracy. Furthermore, the other two arms of the bridge consist of fixed resistors (second resistor 207 and third resistor 208), which, together with the Pt100 temperature sensor 204 and the first adjustable resistor 205, ensure that the bridge generates a differential voltage when the operating temperature deviates from the reference temperature. Temperature compensation unit output voltage:

[0035] in, K For the differential amplifier gain, V i =V drive .

[0036] This embodiment achieves a leap from coarse global compensation to precise array element-level local compensation by using a structure of four piezoresistive elements as a group and incorporating a Wheatstone bridge temperature compensation unit. This design can sense and respond in real time to changes in the spatially distributed temperature gradient on the array surface, performing independent and differentiated compensation calibration for array elements in different temperature regions. This solves the overall measurement error problem caused by thermal field inhomogeneity, minimizes the impact of temperature drift, and thus ensures the accuracy and consistency of the entire array measurement data even in complex thermal environments.

[0037] Figure 4 This is a circuit diagram of the internal circuitry of a 2×2 piezoresistive sensor array shown in an embodiment of the present invention; see reference. Figure 4 The first operational amplifier 101, the positive input terminal of the first operational amplifier 101 is connected to V drive The output terminal is connected to one end of the first resistor 104, and the other end of the first resistor 104 is connected to the negative input terminal. The output terminal of the first operational amplifier 101 is also connected to one end of the fourth adjustable resistor 211, one end of the fifth adjustable resistor 212, the voltage input terminal 202 of the Wheatstone bridge circuit, one end of the second adjustable resistor 209, and one end of the third adjustable resistor 210. The other end of the fourth adjustable resistor 211 is connected to the other end of the second adjustable resistor 209 and the negative input terminal of a third operational amplifier 301. The negative input terminal of the third operational amplifier 301 is also connected to the fourth resistor 302. The output terminal of the third operational amplifier 301 is connected to the temperature-compensated voltage adder 4. The other end of the fifth adjustable resistor 212 is connected to the other end of the third adjustable resistor 210 and the negative input terminal of another third operational amplifier 301. The negative input terminal of the other third operational amplifier 301 is connected to its output terminal and the temperature-compensated voltage adder 4 via the fourth resistor 302. The positive input terminal of the other third operational amplifier 301 is connected to the ground via the fifth resistor 303. The node between the reference arm and the adjacent fixed resistor (second resistor 207) in the Wheatstone bridge circuit is connected to the positive input terminal of the second operational amplifier 206. The node between the temperature-sensitive arm and the adjacent fixed resistor (third resistor 208) in the Wheatstone bridge circuit is connected to the negative input terminal of the second operational amplifier 206. The output terminal of the second operational amplifier 206 is connected to the temperature-compensated voltage adder 4.

[0038] In this embodiment, a 2×2 piezoresistive sensor array is used, controlled by a selector switch to acquire the voltage values ​​of its internal piezoresistive elements. Each element contains a temperature-compensated bridge circuit. When acquiring the resistance signal of a specific piezoresistive element, the selector switches for that row and column are closed. The output voltage is then conducted through the resistive sensing unit detection circuit 3 to the temperature-compensated voltage adder 4, where it is added to the output voltage of the central bridge circuit of that element. The final output is the temperature-corrected piezoresistive voltage value.

[0039] The specific calculation process includes: selecting the fifth adjustable resistor 212 (R) 21 Taking the piezoresistive unit's voltage detection as an example, the positive phase voltage of its input adder can be calculated as follows:

[0040] in, This indicates the resistance value of the fourth resistor.

[0041] Therefore, its final output voltage after temperature compensation should be:

[0042] Figure 4 The physical and electrical connection between the piezoresistive sensing array and the temperature compensation unit was further clarified, demonstrating the structural integration and functional synergy of the array elements. This not only realized the detection of pressure signals but also completed the integrated design of local temperature compensation and crosstalk suppression.

[0043] Figure 5 This is a schematic diagram of the pin definition of the array element expansion interface shown in an embodiment of the present invention; see reference. Figure 5 The interface includes a power supply pin VCC, a ground pin GND, an enable signal EN, and a row selection binary encoding port (a r b r c r ) and column selection binary encoded port (a c b c c c The row and column selection ports are used to control the on / off state of the multiplexer, while the enable port is used by the MCU to control the acquisition enable state of a specific 8×8 array unit, effectively preventing bus crosstalk between different array units. This interface design is fully functional, simple in structure, and supports modular expansion and adaptive networking of large-scale sensor arrays.

[0044] Figure 6 This is a schematic diagram illustrating the extended connection of an MCU controlling four 8×8 array units via a 2-to-4 decoder 901, as shown in an embodiment of the present invention; see reference. Figure 6The row and column selection lines of each array unit are connected in parallel to the MCU's row and column gating bus via the array expansion interface 902, and the ADC output lines are also connected in parallel to the MCU's ADC bus. The enable port of each unit is controlled by the output of the 2-to-4 decoder 901, ensuring that only one array unit is enabled at a time, at which point the row and column gating bus 10 is only valid for that unit. This configuration enables ordered scanning of array units of 8×8×4 and above, greatly simplifying the acquisition and control structure of multi-module systems.

[0045] The standardized array expansion interface architecture proposed in this embodiment liberates the system from rigid centralized control to a flexible, modular, distributed organization. Based on a 64-unit expansion module, a unified digital interface and enable control enable plug-and-play seamless expansion of large-scale arrays. This design simplifies system wiring, reduces the marginal cost of channel expansion, and effectively avoids the attenuation and interference problems of long-distance analog signal transmission, making it possible and easy to construct ultra-high-density arrays with thousands or even larger sensor units.

[0046] Figure 7 This is a framework diagram of a temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit control system according to an embodiment of the present invention; refer to Figure 7 The system includes: a temperature compensation module, an enable module, a row and column gating module, an anti-crosstalk module, a voltage follower module, a power supply module, an array expansion interface, an MCU, and a host computer. The row and column gating module is connected to the temperature compensation module, the anti-crosstalk module, and the voltage follower module, respectively. The row and column gating module is also connected to the MCU via an ADC. The MCU is connected to the array expansion interface via an enable bus. The MCU is also connected to the host computer. The power supply module is used for power supply.

[0047] In this embodiment, a microcontroller unit (MCU) coordinates the operation of various functional modules, including row and column gating control, temperature compensation, crosstalk prevention, voltage tracking, and analog-to-digital conversion, to achieve efficient data acquisition from an 8×8 basic sensor array. During operation, the MCU first initializes the system and activates the designated basic array cells via the row and column gating bus 10. Then, it scans row by row and column by column in a predetermined order, selecting only one sensor cell at a time to avoid signal interference. When acquiring the electrical signal generated by the selected sensor cell, the crosstalk prevention module suppresses piezoresistive coupling between adjacent cells, and the temperature compensation module corrects its temperature drift. Next, the signal is buffered and amplified by the voltage tracking module before entering the ADC for digital processing. Finally, the MCU collects and uploads the data to the host computer software for further data processing, analysis, and visualization. Furthermore, the system supports cascading expansion of multiple basic array cells, enabling the construction of a large-scale sensor network. It features high precision, low crosstalk, and good scalability, making it suitable for applications in various complex environments. This system design embodies a complete link architecture from physical signal acquisition to digital information output, demonstrating the technological innovation of combining integrated design with intelligent control.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit, characterized in that, include: Several array units, each array unit is connected to the MCU through the MCU expansion array enable module, and the MCU is connected to the host computer; Each array unit includes: The row drive circuit is connected to the drive voltage and selects a specific row; Piezoresistive sensor arrays are used for temperature compensation of the output voltage of the row drive circuit. The resistive sensing unit detection circuit is used to keep the output non-gated column line voltage zero; A temperature-compensated voltage adder is used to sum the temperature-compensated voltage signal output by the piezoresistive sensor array and the output voltage signal of the resistive sensing unit detection circuit. The multiplexing circuit is connected to the temperature-compensated voltage adder and the voltage follower respectively. The multiplexing circuit is used to select the output voltage signal of the temperature-compensated voltage adder in a specific column and isolates the output from the front and rear stages through the voltage follower. An inverter is used to convert the output voltage signal of a voltage follower into a positive voltage and output it to the microcontroller's ADC acquisition module. The microcontroller ADC acquisition module is used to control the row and column gating and data acquisition process.

2. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 1, characterized in that, The row driving circuit includes: a first operational amplifier, a row multiplexer, and a row selection binary encoding port. The positive input terminal of the first operational amplifier is connected to the driving voltage, and both the negative input terminal and the output terminal of the first operational amplifier are connected to the row multiplexer. The row multiplexer is equipped with a row selection binary encoding port.

3. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 1, characterized in that, The piezoresistive sensing array includes several temperature compensation units. Each temperature compensation unit has a voltage input terminal and a temperature compensation voltage output terminal, and they are connected through a row multiplexer. When a row is selected, the voltage input terminals of all temperature compensation units in the same row are activated, and the temperature compensation voltage signal output by the temperature compensation voltage output terminal is transmitted to the temperature compensation voltage adder.

4. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 3, characterized in that, The piezoresistive sensing array includes one end of a fourth adjustable resistor connected to the output of the row drive circuit, one end of a fifth adjustable resistor, the voltage input terminal of the 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 to the other end of the second adjustable resistor and the resistive sensing unit detection circuit, respectively. The other end of the fifth adjustable resistor is connected to the other end of the third adjustable resistor and the resistive sensing unit detection circuit, respectively.

5. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 4, characterized in that, The Wheatstone bridge circuit uses a temperature sensor as the temperature-sensitive arm to convert the temperature signal into a differential voltage output; it uses a first adjustable resistor as the reference arm to adjust the balance of the Wheatstone bridge circuit at a reference temperature; the diagonal of the Wheatstone bridge circuit is connected to the positive and negative input terminals of the second operational amplifier, and the output terminal of the second operational amplifier is connected to a temperature-compensated voltage adder. The second operational amplifier is used to amplify the differential voltage signal output by the Wheatstone bridge circuit, and the other two 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, characterized in that, The output voltage of the temperature compensation unit is expressed by the following formula: in, K V is the gain of the second operational amplifier. i R represents the input voltage of the Wheatstone bridge circuit. ref R represents the resistance value of the first adjustable resistor. 207 R represents the resistance value of the second resistor. Pt100 R represents the resistance value of the temperature sensor. 208 This indicates the resistance value of the third resistor.

7. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 4, characterized in that, The resistive sensing unit detection circuit includes two identical amplifier circuits. Each amplifier circuit includes a third operational amplifier, a fourth resistor, and a fifth resistor. The negative input terminal of the third operational amplifier is connected to the output terminal of the piezoresistive sensing array and one end of the fourth resistor, respectively. The positive input terminal of the third operational amplifier is grounded through the fifth resistor. The output terminal of the third operational amplifier and the other end of the fourth resistor are both connected to a temperature-compensated voltage adder.

8. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 1, characterized in that, The row and column selection lines of each array unit are connected in parallel to the MCU's row and column gating bus and decoder via the array expansion interface.

9. The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to claim 8, characterized in that, The array expansion interface includes: a power supply pin, a ground pin, an ADC pin, an enable signal, a row selection binary encoding port, and a column selection binary encoding port; the row selection binary encoding port and the column selection binary encoding port are used to control the on / off state of the multiplexer; the enable port is used by the MCU to control the acquisition enable state of the array unit; the ADC pin output line is also connected in parallel to the MCU's ADC bus.

10. A temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit control system, characterized in that, The temperature-compensated anti-crosstalk piezoresistive sensor array acquisition circuit according to any one of claims 1-9 includes: a temperature compensation module, an enable module, a row and column gating module, an anti-crosstalk module, a voltage follower module, a power supply module, an array expansion interface, an MCU, and a host computer. The row and column gating module is connected to the temperature compensation module, the anti-crosstalk module, and the voltage follower module, respectively. The row and column gating module is also connected to the MCU through an ADC. The MCU is connected to the array expansion interface through an enable bus. The MCU is also connected to the host computer. The MCU activates the designated base array cells through the enable bus, and then scans them row by row and column by column in a predetermined order, controlling the row and column gating module to select only one sensing cell at a time. When acquiring the electrical signal generated by the selected sensing cell, the anti-crosstalk module suppresses the piezoresistive coupling between adjacent cells, and then the temperature compensation module corrects its temperature drift. The signal is buffered and amplified by the voltage follower module and then enters the ADC for digital processing. Finally, the MCU collects and uploads the data to the host computer software to complete further data processing, analysis and visualization.

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