Temperature measuring element network scanning surface temperature detection device and method

Abstract

This application relates to the field of information transmission technology, and in particular to a temperature detection device and method for a network scanning surface of temperature sensing elements. The device includes: a power supply, controllable acquisition points, column drive switches, and a current sampling shunt resistor. Multiple controllable acquisition points are connected via an array arrangement. Each controllable acquisition point includes a P-channel MOSFET and a temperature-sensing platinum resistance thermometer. The controlled terminals of multiple column drive switches are connected to the lower end of each column voltage divider resistor. Each column drive switch includes an N-channel MOSFET. One end of the current sampling shunt resistor is grounded, and the other end is connected to the lower collinear temperature-sensing platinum resistance thermometer. The device can significantly reduce the number of temperature sensing wires, lower the difficulty of wiring construction and material costs; it eliminates the cumbersome architecture of multiple units with multi-channel polling sampling, simplifying system assembly.

Description

Technical Field

[0001] This application relates to the field of information transmission technology, and in particular to a temperature detection device and method for a network scanning surface of a temperature sensing element. Background Technology

[0002] In the production control and environmental thermal radiation detection scenarios of chemicals, new materials, and new processing technologies, it is often necessary to deploy a large number of sampling points to complete the temperature monitoring of the entire area. At present, the traditional temperature acquisition solution commonly used in the industry is to configure multiple independent temperature acquisition units. The analog signals output by the front-end temperature sensing elements are led out through wiring, and the back-end ADC multi-channel time-division multiplexing mode is used to complete the signal sampling and conversion sequentially. When facing the large number of temperature measurement deployment points such as 16×16, this traditional architecture requires a large number of connecting leads. The complicated wiring structure not only significantly increases the difficulty of on-site wiring construction and the implementation complexity of equipment assembly, but also significantly increases the hardware investment and construction cost of the entire temperature measurement system due to increased cable consumption, increased wiring labor costs, and increased supporting wiring accessories. At the same time, dense leads are also prone to derivative problems such as line crossing interference and difficulty in troubleshooting wiring faults, making it difficult to adapt to the actual use needs of lightweight and low-cost deployment in multi-point high-density temperature detection scenarios.

[0003] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0004] The main objective of this application is to propose a temperature detection device and method for a network scanning surface of a temperature sensing element, which can significantly reduce the number of temperature sensing wires, reduce the difficulty of wiring construction and the cost of consumables; and eliminate the cumbersome architecture of multiple units with multi-channel polling sampling, thus simplifying system assembly.

[0005] To achieve the above objectives, one aspect of this application provides a temperature detection device for a network scanning surface of a temperature sensing element, comprising: Power supply; A controllable acquisition point is provided, wherein multiple controllable acquisition points are connected by an array arrangement. Each controllable acquisition point includes a P-channel field-effect transistor (FET) and a temperature-sensing platinum resistance thermometer (RTD). The source of the P-channel FET is connected to the power supply via a pull-up resistor, and the power supply is connected to the gate of the P-channel FET via the pull-up resistor. The drain of the P-channel FET is connected in series with the RTD and then connected to a parallel current sampling output circuit. The gates of all P-channel FETs in the same column are collinear and then connected to the upper end of a voltage divider resistor. A column drive switch is provided, with the controlled terminals of multiple column drive switches respectively connected to the lower terminals of the voltage divider resistors in each column. Each column drive switch includes an N-channel field-effect transistor (FET), the gate of which is connected to a column drive signal, and the source of which is grounded. The column drive signal controls the switching on and off of the N-channel FET. When the column drive switch of a corresponding column is turned on, it pulls down the voltage divider resistor, thereby connecting the controllable acquisition point of the corresponding column to the current sampling output circuit. A current sampling shunt resistor is provided, with one end of the current sampling shunt resistor grounded. All the temperature measuring platinum resistance thermometers in the same row are connected to the other end of the current sampling shunt resistor after their lower ends are collinear. The controllable acquisition points in different rows acquire the loop current according to their respective current sampling shunt resistors. The resistance value of the platinum resistance thermometer and the temperature of the measuring point are calculated by using the voltage across the current sampling shunt resistor.

[0006] In some embodiments, all controllable acquisition points in a row share the same current sampling shunt resistor; After all the controllable acquisition points in a row are turned on, the turned-on controllable acquisition points are connected in series and connected to the current sampling shunt resistor to obtain the temperature measurement sampling branch; wherein, the controllable acquisition points in different rows collect the loop current according to their respective current sampling shunt resistors; The loop current of a single temperature sampling branch is sampled by voltage division through the resistor of the current sampling shunt to obtain a sampled voltage signal.

[0007] In some embodiments, all controllable acquisition points in the same column share a set of voltage divider resistors and the column drive switch; The column drive signal is input to the gate of the N-channel field-effect transistor. The column drive signal controls the conduction of the N-channel field-effect transistor. When the N-channel field-effect transistor is turned on, the gate potential of all the P-channel field-effect transistors in the same column is pulled down by the voltage divider resistor, so that the controllable acquisition points in the same column are synchronously selected.

[0008] In some embodiments, the gate of each of the P-channel field-effect transistors is connected to an independent pull-up resistor; The other end of the pull-up resistor is connected to the power supply. When the controllable acquisition point is in the disconnected state, the pull-up resistor is used to maintain the gate high level of the P-channel field-effect transistor, so that the P-channel field-effect transistor is in the off state.

[0009] In some embodiments, it also includes a microcontroller digital control circuit board and a front-end gating acquisition circuit board; The microcontroller digital control circuit board includes multiple general-purpose input / output ports, a filtering circuit, and an analog-to-digital conversion acquisition circuit. The multiple general-purpose input / output ports output column gating control signals and row gating control signals respectively. The column gating control signals and the row gating control signals are transmitted to the front-end gating acquisition circuit board. The column gating control signal and the row gating control signal are processed by the front-end gating acquisition circuit board to perform time-division filtering and channel gating on the sampling voltage signal generated by the current sampling shunt resistor in each row, so as to obtain the current sampling gating output signal. The front-end gating acquisition circuit board transmits the current sampling gating output signal sequentially to the filtering circuit and the analog-to-digital conversion acquisition circuit for filtering and analog-to-digital conversion to obtain a digital voltage value.

[0010] In some embodiments, a column drive link is formed by the pull-up resistors, the voltage divider resistors, and the N-channel MOSFETs in the same column of the controllable acquisition points; The column-driven link further includes a first-level column selector and a second-level column selector. The first-level column selector is connected to a high-order gating code, and the output of the first-level column selector is connected to multiple groups of second-level column selectors. Each group of second-level column selectors is connected to a low-order gating code. The high-bit gating code and the low-bit gating code are cascaded and decoded by the first-level column gating device and the second-level column gating device to obtain multiple column driving signals.

[0011] In some embodiments, a row driving link is also included, wherein the temperature measuring platinum resistance, the P-channel field-effect transistor and the current sampling shunt resistor connected in series in the same row form a row sampling branch, and the row driving link is connected to the output terminal of the row sampling branch; The row drive link includes a first-level row selector and a second-level row selector. The first-level row selector is connected to a high-order gating code, and the output of the first-level row selector is connected to multiple groups of second-level row selectors. Each group of second-level row selectors is connected to a low-order gating code. The first-stage row selector and the second-stage row selector perform concatenated decoding and gating processing on the high-bit gating code and the low-bit gating code to obtain multiple row driving signals. The multiple row driving signals are used to time-division select the row sampling branch and filter the output sampling voltage signal. The second-stage row selector receives the sampled voltage signal. The first-stage row selector generates a selection command based on the row selection control signal and sends the selection command to the second-stage row selector. The second-stage row selector performs time-division initial selection on the sampled voltage signal to obtain multiple sampled output signals. After transmitting the multiple sampled output signals to the first-stage row selector, the multiple sampled output signals are summarized to obtain a current sampling selection output signal. The current sampling selection output signal is output to a filter circuit and an analog-to-digital conversion acquisition circuit for analog-to-digital conversion processing to obtain the digital voltage value.

[0012] To achieve the above objectives, another aspect of this application proposes a method for detecting the temperature of a temperature sensing element network scanning surface. This method is applied to the temperature sensing device of claim 7, and includes the following steps: The column gating control signal output by the column driving link is configured through the multi-channel general-purpose input / output port to obtain multi-channel column driving logic signals; The column drive logic signal is used to control the on / off state of the column drive switch, so that all the controllable acquisition points of the target column are connected to the sampling circuit, and a single column continuity measurement point array is obtained. The high-bit gating code and low-bit gating code output from the multi-channel general-purpose input / output port are cascaded and decoded by the first-stage row selector and the second-stage row selector to obtain the multi-channel row drive signal. The row selection control signal output by the row drive link is selected and scheduled row by row according to the row drive signal, and each row current sampling branch is selected sequentially according to the single column conduction measurement point array to obtain the sampling voltage signal. The sampled voltage signals are aggregated through the row drive link to obtain the current sampling gating output signal; The current sampling gating output signal is filtered and converted from analog to digital by the filtering circuit and the analog-to-digital conversion acquisition circuit to obtain the digital voltage value. The actual operating current of the circuit is obtained by performing Ohm's law calculation on the digital voltage value based on the nominal resistance of the shunt. The total impedance of the platinum resistance circuit is calculated by converting the voltage of the power supply and the actual operating current of the circuit to obtain the real-time resistance value of the platinum resistance to be tested. The real-time resistance value of the platinum resistance to be measured is converted by looking up a table using the correspondence between the resistance value of the platinum resistance and the temperature, so as to obtain the measured temperature of the controllable acquisition point. The row and column selection combinations of the controllable acquisition points in the array are cyclically switched and calculated separately until the temperature acquisition of all the controllable acquisition points in the array is completed, thereby obtaining the set of platinum resistance data corresponding to all the controllable acquisition points in the array and the set of temperature data of each measurement point.

[0013] In some embodiments, the process of sequentially selecting and scheduling the row selection control signal output from the row drive link through the multiplex universal input / output port, and sequentially selecting each row current sampling branch according to the single-column conduction measurement point array to obtain the sampled voltage signal, includes the following steps: The row selection control signal and the column selection control signal output by the microcontroller digital control circuit board are transmitted to the front-end selection acquisition circuit board through a ribbon cable to obtain row and column logic selection signals; The row drive link and the column drive link perform array gating control on the controllable acquisition points according to the row and column logic gating signals to obtain the sampled voltage signal.

[0014] In some embodiments, configuring the column gating control signal output by the column driving link through the multiplex general-purpose input / output port to obtain multiple column driving logic signals includes the following steps: The column selection control signal is output to the column drive link through the multi-channel general-purpose input / output port to complete the column selection configuration. The gate of the P-channel field-effect transistor that is not selected in the column is pulled up to a high level by the pull-up resistor, so that the controllable acquisition point of the corresponding column remains open. The target column circuit is activated by pulling down the column drive switch, thereby obtaining multiple column drive logic signals.

[0015] The embodiments of this application include at least the following beneficial effects: This application provides a temperature detection device and method for a network scanning surface of a temperature sensing element. This scheme uses a platinum resistance thermometer connected in series with a P-channel field-effect transistor to form controllable acquisition points, arranged in a row-column array. Measurement points in the same row share a single current sampling shunt resistor. A column drive switch, consisting of a voltage divider resistor for the gate of the P-channel field-effect transistor and an N-channel field-effect transistor, achieves synchronous selection of the entire column. Under normal conditions, the pull-up resistor pulls the gate of the P-channel field-effect transistor to a high potential, turning off the P-channel field-effect transistor and disconnecting the measurement point circuit. The voltage divider resistor is only pulled low when the column drive switch is on. Only after the corresponding column measurement point is connected to the sampling circuit can the array measurement points be controlled and selected column by column by column based on the column drive signal, avoiding the mutual interference problem caused by parallel conduction of multiple points. At the same time, all temperature measuring platinum resistances in the same row share a common current sampling shunt after their lower ends are collinear to complete the current sampling. This abandons the traditional layout of independent wiring for single-point temperature measurement and multi-channel polling sampling, which greatly reduces the number of leads extending from the array measurement points to the back end, effectively reducing the difficulty of on-site wiring construction, cable consumption and assembly costs. The platinum resistance value and measurement point temperature can be uniformly converted based on the voltage at both ends of the shunt, simplifying the back-end sampling hardware configuration. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the temperature detection device for the network scanning surface of the temperature sensing element provided in the embodiments of this application; Figure 2 yes Figure 1 A schematic diagram of controllable acquisition points in the system; Figure 3 This is a schematic diagram of the first-level column selector and the second-level column selector; Figure 4 This is a schematic diagram of the first-level row selector and the second-level row selector; Figure 5 This is a schematic diagram of the microcontroller unit's digital control circuit board; Figure 6 This is a schematic diagram of the transmission of the gating control signal. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0018] Unless otherwise defined, 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 application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0019] Before providing a detailed description of the embodiments of this application, some of the nouns and terms involved in the embodiments of this application will be explained first. The nouns and terms involved in the embodiments of this application are subject to the following interpretations.

[0020] P-channel MOSFET: PMOS, a voltage-type switching device, can be turned on when the gate voltage is lower than the source voltage; this circuit is equipped with a pull-up resistor, and normally the gate is turned off when it is high.

[0021] N-channel MOSFET: NMOS, which can conduct when the gate voltage is higher than the source voltage.

[0022] AT32F435 (ARM M4F core): ARM-M4F core industrial-grade microcontroller unit (MCU) with built-in hardware ADC and multiple GPIOs.

[0023] IRLML6402TRPBF: This is a PMOS model with an on-resistance of 65mΩ and Vgs=-4.5V.

[0024] PT100 platinum resistance thermometer: a high-precision temperature sensing element with a resistance of 100Ω at 0℃, and the resistance changes linearly with temperature.

[0025] IRLML6244TRPBF: This is an NMOS model with an on-resistance of 27mΩ and Vgs=2.5V. It acts as a column drive switch, grounding to pull down the voltage divider resistor to achieve synchronous selection of all PMOS in the same column.

[0026] MUX708 8-to-1 analog switch: TI's multi-channel analog gating chip, 8 channels per chip.

[0027] The temperature detection device, consisting of a network scanning surface of temperature sensing elements, is equipped with a power supply. Multiple controllable acquisition points, each composed of a P-channel MOSFET connected in series with a platinum resistance thermometer, are arranged in a row and column array. The source of the P-channel MOSFET is connected to the power supply via a pull-up resistor. The power supply provides a pull-up potential to the gate of the P-channel MOSFET through the pull-up resistor. The drain of the P-channel MOSFET is connected in series with the platinum resistance thermometer and then connected to the same-column current sampling output circuit. The gates of all controllable acquisition points in the same column are connected to the upper end of a voltage divider resistor. A column drive switch composed of N-channel MOSFETs is configured, and each column drive... The controlled terminals of the active switch are connected to the lower ends of the corresponding column voltage divider resistors. The gate of the N-channel MOSFET is connected to the column drive signal, and the source is grounded. After the column drive signal controls the N-channel MOSFET to turn on, it pulls down the potential of the voltage divider resistor, so that the controllable acquisition point of the corresponding column is connected to the current sampling output circuit. Each row is configured with a current sampling shunt resistor with one end grounded. The lower ends of all temperature measuring platinum resistance thermometers in the same row are collinear and connected to the other end of the current sampling shunt resistor in that row. Each row collects the loop current based on its own configured current sampling shunt resistor, and uses the voltage across the shunt to convert the resistance value of the platinum resistance thermometer to the temperature of the measuring point.

[0028] like Figure 1 and Figure 2 As shown, Figure 1 In the diagram, R11, R12, R13, R14, R15, and R16 represent pull-up resistors; R21, R22, R23, R24, R25, and R26 represent temperature-sensing platinum resistance thermometers; R31 and R32 represent current-sampling shunt resistors; R41, R42, and R43 represent voltage divider resistors; Q11, Q12, and Q13 represent column drive switches; and Vpower represents the power supply. The temperature detection device for the network scanning surface of the temperature sensing element is equipped with a power supply, an array of controllable acquisition points, column drive switches, and dedicated current sampling shunt resistors for each row. Each controllable acquisition point consists of a P-channel MOSFET connected in series with a temperature-sensing platinum resistance thermometer. The gate of each P-channel MOSFET is individually equipped with a pull-up resistor, and the other end of the pull-up resistor is connected to the power supply. The power supply provides a static pull-up potential to the gate of the P-channel MOSFET through the pull-up resistor. When the controllable acquisition point is not selected, the pull-up resistor keeps the gate of the P-channel MOSFET at a high level, causing the P-channel MOSFET to remain in the off state, blocking the corresponding temperature-sensing platinum resistance thermometer from accessing the sampling circuit, and avoiding electrical interference to the sampling line caused by unselected measurement points. The drain of the P-channel MOSFET is connected in series with the temperature-sensing platinum resistance thermometer and then connected to the current sampling output circuit of the corresponding row. Multiple controllable acquisition points are arranged in an array according to row and column rules. Controllable acquisition points in the same column constitute the same-column acquisition point, and controllable acquisition points in the same row constitute the same-row acquisition point.

[0029] The temperature detection device for the network scanning surface of the temperature sensing element is equipped with voltage divider resistors and column drive switches composed of N-channel field-effect transistors (FETs) in each column. The gates of all controllable acquisition points in the same column are connected to the upper end of the voltage divider resistor after being collinear. The lower end of the voltage divider resistor is connected to the drain of the corresponding column drive switch, i.e., the N-channel FET. The gate of the N-channel FET is connected to the column drive signal, and the source is grounded. When the column drive signal controls the N-channel FET to conduct, it will pull down the gate potential of the entire column of P-channel FETs through the voltage divider resistor. After the gate high level is pulled low, the P-channel FETs conduct, realizing the synchronous selection of all controllable acquisition points in the same column and connecting them to the current sampling output circuit. Only one voltage divider resistor and one column drive switch are required for each column to achieve unified control of the entire column of measurement points, which greatly reduces the number of column control components and simplifies the array front-end drive wiring.

[0030] The temperature detection device uses a network scanning surface with temperature sensing elements. Each row of the network is independently equipped with a current sampling shunt resistor. One end of the current sampling shunt resistor is grounded. The lower ends of the temperature-sensing platinum resistors at all controllable acquisition points in the same row are collinear and connected to the other end of the current sampling shunt resistor in that row. That is, all controllable acquisition points in a row share a single current sampling shunt resistor. When any controllable acquisition point in a row is selected and turned on, the turned-on controllable acquisition point and the current sampling shunt resistor in that row are connected in series to form a complete temperature sampling branch. Under constant power supply voltage, the resistance of the temperature-sensing platinum resistor will change with the ambient temperature, which will cause the current in the temperature sampling branch to change synchronously. When the changing current flows through the current sampling shunt resistor, it will generate a differentiated sampling voltage signal across the shunt resistor. The device collects the value of this sampling voltage signal, calculates the branch current by combining it with the known resistance of the current sampling shunt, and then calculates the real-time resistance value of the temperature-sensing platinum resistor based on the power supply voltage and the loop current. Finally, it calculates the actual temperature of the corresponding measurement point based on the temperature resistance characteristics of the platinum resistor.

[0031] The entire temperature sensing element network scanning surface temperature detection device relies on an array topology structure with unified selection on the column side and shared sampling resistors on the row side. It abandons the traditional wiring scheme of separate leads and separate configuration of sampling elements for single-point platinum resistance thermometers. A large number of temperature measurement points can be sampled in a time-division manner by simply grouping and controlling rows and columns. This greatly reduces the number of wires between the front-end acquisition array and the back-end processing circuit, reducing the cost of wiring and the probability of wiring failure. At the same time, non-selected measurement points are reliably shut off and isolated by pull-up resistors, effectively eliminating parallel leakage interference between multiple measurement points, improving the accuracy of sampling voltage signal acquisition, and ensuring the accuracy of subsequent calculation of platinum resistance value and measurement point temperature.

[0032] In some embodiments, such as Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, Figure 3The system consists of a first-level column selector and multiple sets of second-level column selectors. The first-level column selector is connected to the power supply Vpower and the high-order coded signal, with multiple outputs connecting to each set of second-level column selectors. Each set of second-level column selectors is connected to the low-order coded signal. After two stages of decoding and expansion, each set of second-level column selectors outputs eight column drive signals in parallel, corresponding to column 0-7 and N+0-N+7 drive signals, respectively. By relying on hierarchical decoding of high and low-order coded signals, a small number of control codes can be expanded into a large number of column drive signals, significantly reducing the number of pins and front-end wiring on the microcontroller's digital control circuit board. Figure 4 Multiple raw horizontal sampling voltage signals are input from the right side to each of the second-stage horizontal selectors, which receive the low-order selection code. The first-stage horizontal selector receives the high-order code and outputs a control signal to each group of second-stage horizontal selectors. The second-stage horizontal selector performs time-division initial selection on the multiple sampled voltage signals and sends them to the first-stage horizontal selector. The first-stage selector then aggregates the signals to generate a single-channel current sampling selection output signal, which is sent to the left to the filtering and analog-to-digital conversion circuit. The two-stage selection achieves time-division merging and output of multiple horizontal sampling channels, thereby reusing the back-end analog-to-digital conversion hardware resources and reducing the number of back-end sampling circuits. Figure 5 The microcontroller unit's digital control circuit board has two sets of GPIO pins: the upper set (s0-s5 pins) outputs column gating control signals, serving as the high and low bit decoding encoding for the two-stage column selector; the lower set (s0-s5 pins) outputs row gating control signals, providing decoding control encoding for the two-stage row selector. The microcontroller unit's digital control circuit board can output the entire set of row and column encoded signals using only a limited number of GPIOs, eliminating the need for independent pins for each driver, thus simplifying the main control hardware resources. The encoded signals are transmitted to the front-end gating and acquisition circuit board via ribbon cables. Figure 6 The left side of the panel contains the microcontroller unit's digital control circuit board, while the right side contains the front-end gating and acquisition circuit board. The two boards communicate via a ribbon cable. Column and row gating control signals are sent downwards from the back-end microcontroller unit's digital control circuit board to the front-end gating and acquisition circuit board via the ribbon cable. The current sampling gating output signal is transmitted back from the front-end gating and acquisition circuit board to the back-end microcontroller unit's digital control circuit board via the ribbon cable. This bidirectional transmission architecture, with control signals going down and sampling signals going up, allows for centralized deployment of gating devices in the front-end array, while the back-end handles computation and acquisition. It enables signal interaction for a large-scale temperature measurement array using a small number of ribbon cables, simplifying the overall wiring harness.

[0033] In some embodiments, the temperature sensing element network scanning surface temperature detection device is divided into two main hardware partitions: a microcontroller digital control circuit board and a front-end gating acquisition circuit board. The two circuit boards communicate with each other via ribbon cables. Figure 5 As shown, the microcontroller's digital control circuit board is equipped with two sets of GPIO ports, which generate six column strobe control signals (s0-s5) and six row strobe control signals, respectively. The column and row strobe control signals serve as strobe instructions, such as... Figure 6 As shown, the signal is transmitted downwards via a ribbon cable to the front-end selection and acquisition circuit board. The main controller can output a complete set of decoding control signals using only a few GPIO pins, abandoning the traditional one-to-one pin direct drive design and simplifying the layout of the back-end main control circuit.

[0034] The front-end gating and acquisition circuit board is equipped with a column drive link. This link consists of pull-up resistors for the controllable acquisition points in the same column, voltage divider resistors, N-channel MOSFETs acting as column drive switches, a first-stage column selector, and multiple sets of second-stage column selectors. The first-stage column selector is connected to the high-order gating code and the power supply Vpower. Its multiple outputs are connected to each set of second-stage column selectors, each receiving the low-order gating code. The two stages of gating devices work together to complete the cascaded decoding. Each set of second-stage column selectors outputs eight column drive signals in parallel, driving the corresponding column drive switches. When the switches are turned on, they pull down the voltage divider resistor potential, simultaneously activating the entire column of controllable acquisition points connected to the temperature measurement circuit. This hierarchical decoding expands the multiple drive levels, significantly reducing the number of control lines from the back-end to the front-end.

[0035] A front-end synchronously deployed horizontal drive link consists of a horizontal sampling branch formed by a series-connected temperature-sensing platinum resistance thermometer, a P-channel MOSFET, and a current sampling shunt resistor. The horizontal drive link is connected to the output of the horizontal sampling branch. The horizontal drive link includes a first-stage horizontal selector and multiple sets of second-stage horizontal selectors. The first-stage horizontal selector receives the high-order selection code, and its output is connected to multiple sets of second-stage horizontal selectors. Each set of second-stage horizontal selectors synchronously receives the low-order selection code. The first-stage and second-stage horizontal selectors work together to complete the cascaded decoding of the high and low-order codes and channel selection, ultimately generating multiple horizontal drive signals. The horizontal drive signals serve as control commands, switching each horizontal sampling branch in a time-division multiplexing manner, while simultaneously filtering and outputting the sampled voltage signals generated by the branches, achieving orderly management of the multi-channel sampling branches. All sampled voltage signals are uniformly connected to the second-stage horizontal selector, and the first-stage horizontal selector issues selection commands to the next-stage circuit based on the horizontal selection control signal. The second-stage row selector performs time-division initial selection on the sampled voltage signal according to the instruction, outputting multiple sampled output signals. These multiple sampled output signals are then transmitted to the first-stage row selector for aggregation. The first-stage row selector completes the aggregation and integration of all signals, outputting a single-channel current sampling gating output signal. The current sampling gating output signal is sequentially sent to the back-end filtering circuit and the analog-to-digital conversion acquisition circuit. First, interference noise in the signal is filtered out, and then the analog signal is converted into a digital voltage value, providing standard data for subsequent resistance and temperature calculations.

[0036] The column and row selection control signals are sent unidirectionally from the back-end microcontroller unit's digital control circuit board to the front end via a ribbon cable. The front end, relying on the column and row drive links, time-division multiplexes the array measurement points, filters and samples the voltage signals, and generates a current sampling selection output signal. The analog signal, along with the ground wire, is transmitted back to the microcontroller unit's digital control circuit board via the ribbon cable, where it is fed into the onboard filtering and analog-to-digital conversion circuit to generate a digital voltage. The microcontroller unit's digital control circuit board calculates the loop current based on the shunt's nominal resistance value, calculates the platinum resistance value based on the supply voltage, and then calculates the measurement point temperature. It cyclically switches row and column codes, sequentially traversing all controllable acquisition points to complete the full array temperature measurement.

[0037] To achieve the above objectives, another aspect of this application proposes a method for detecting the temperature of a network scanning surface of a temperature sensing element. The method employs a time-division multiplexing acquisition logic, first column gating and then row-by-row sampling. The microcontroller unit's digital control circuit board outputs control commands via multiple general-purpose input / output ports, working in conjunction with the column and row drive links within the front-end gating acquisition circuit board to complete polling and temperature measurement of the entire array of measurement points.

[0038] During temperature measurement, column gating configuration is completed using a multi-channel general-purpose input / output port, and a column gating control signal is sent to the column drive link. During the column gating configuration phase, the gates of the P-channel MOSFETs in the unselected columns are kept at a high potential via matching pull-up resistors, keeping the temperature detection device on the network scanning surface of the temperature sensing element off. The selected column is driven by the column drive logic signal to turn on the column drive switch. The column drive switch pulls down the voltage divider resistor potential, which in turn pulls down the gate voltage of the P-channel MOSFETs in the same column. The entire column of controllable acquisition points is synchronously turned on and connected to the sampling circuit, forming a single-column conducting measurement point array.

[0039] After single-column gating is completed, row gating control signals are output to the row drive links through multiple general-purpose input / output ports to perform row-by-row gating scheduling. Specifically, the output row and column gating control signals are transmitted via cabling from the back-end microcontroller digital control board to the front-end gating and acquisition board to generate row and column logic gating signals. The column and row drive links then perform gating control of the measurement points and sampling channels based on these signals. Each row current sampling shunt generates a sampling voltage signal as the branch conducts. The front-end gating and acquisition board sends the sampling voltage signal, along with a ground wire, back to the microcontroller digital control board via cabling, achieving cross-board data transmission of the sampling data.

[0040] The returned sampled voltage signal is first sent to a filter circuit to remove interference noise, and then converted into a digital voltage value by an analog-to-digital converter. Based on the nominal resistance of the current sampling shunt and Ohm's law, the actual loop current of the sampling branch is calculated from the digital voltage. Then, combined with the fixed voltage parameters of the power supply, the real-time impedance value of the temperature-sensitive platinum resistance thermometer is inferred. Finally, by referring to a pre-stored table of platinum resistance thermometer resistance-temperature correspondence, the actual temperature of the current conducting measurement point is calculated.

[0041] After a single row and column combination temperature measurement is completed, the row and column gating combinations are cyclically changed, and the entire process of column gating, row sampling, signal conversion, and temperature calculation is repeated, sequentially traversing all controllable acquisition points within the array. After all measurement points have been acquired and processed, the platinum resistance value dataset and the corresponding temperature measurement dataset for all points in the entire array are generated, completing the comprehensive testing of the temperature measurement array. The temperature detection method of the temperature sensing element network scanning surface utilizes a hierarchical gating architecture to enable multiple measurement points to share the back-end acquisition circuit, effectively ensuring the stability and data accuracy of temperature acquisition.

[0042] The following is a detailed description and explanation of the solution of the present invention, with reference to specific application examples: This example is a 32×32 PT100 temperature measurement array with a total of 1024 points. The main control adopts the AT32F435 (ARM-M4F core) microcontroller digital control circuit board. The front end is built with a front-end gating and acquisition circuit board composed of P-channel MOSFETs, N-channel MOSFETs, precision sampling resistors, and multi-channel gating chips. Row and column decoding gating control is achieved by relying on the general GPIO ports of the microcontroller digital control circuit board. Each controllable acquisition point consists of an IRLML6402TRPBF type P-channel MOSFET connected in series with a PT100 platinum resistance thermometer. The source of the P-channel MOSFET is connected to a 12V power supply voltage, and the gate is connected to 12V via a 10kΩ pull-up resistor. Normally, a high gate level turns off the P-channel MOSFET, which matches the control logic of pull-up resistor clamping off in the column gating configuration. The gates of the 32 P-channel MOSFETs in the same column are connected to the drain of the IRLML6244TRPBF type N-channel MOSFET column drive switch via a 1kΩ current-limiting resistor. The source of the N-channel MOSFET is grounded, and the gate is connected to the column drive signal. When the column drive switch is turned on and pulled down, the entire column of P-channel MOSFETs are turned on synchronously, which corresponds to the column control principle of the column drive link.

[0043] A two-stage cascaded selector is constructed using multiple MUX708 8-to-1 analog switches. Two groups of 5-bit codes are used to achieve 1024-channel decoding expansion. The microcontroller unit's digital control circuit board (DCPC) divides PB0-PB4 as row selection control pins and PB8-PB12 as column selection control pins. These two types of pins form a multi-channel general-purpose input / output port, outputting column selection control signals in a time-division multiplexing manner. These column selection control signals are sent to the front-end selection and acquisition circuit board for decoding, generating multiple column drive logic signals. During the detection method execution phase, the DCPC uses a timer to drive GPIO grouping and outputting codes. First, the column selection control signals are configured to select the target column, forming a single-column conduction measurement point array. Then, the row selection control signals are scheduled row by row to sequentially connect each row's sampling branch.

[0044] A PT100 in the same conducting branch is connected in series with a 10Ω, 0.1% precision current sampling shunt resistor. An operational amplifier is then connected to the downstream end of the current sampling shunt resistor to form an active low-pass filter circuit, constituting the sampling voltage signal conditioning link. The filtered analog sampling voltage signal is sent to the ADC analog-to-digital converter (ADC) acquisition circuit corresponding to the PA0 pin of the main control unit, where it is converted into a digital voltage value. The microcontroller's digital control circuit board, based on the nominal resistance of the sampling resistor and the 12V supply voltage, uses Ohm's law to sequentially calculate the branch loop current and the real-time resistance of the PT100, and then refers to the PT100 temperature-resistance comparison table to calculate the single-point measured temperature.

[0045] By integrating row and column gating, array controllable acquisition points, and cascaded gating modules at the front end, and adapting to time-division polling detection methods, each platinum resistance thermometer, paired with a P-channel MOSFET with its pull-up resistor, forms an independent controllable acquisition point. Unselected measurement points are reliably shut off and isolated, effectively suppressing channel crosstalk and leakage problems, and significantly improving temperature sampling accuracy. Controllable acquisition points in the same column share a voltage divider resistor and a single-channel N-channel MOSFET column drive switch, while acquisition points in the same row share a precision current sampling shunt, greatly simplifying the front-end array circuit structure and reducing the number of components and wiring complexity.

[0046] A cascaded architecture enables multi-channel gating capabilities by expanding a small number of coded signals, saving pin resources on the microcontroller's digital control circuit board. The back-end control board uses only a small number of cables to complete command issuance and sampling signal feedback, simplifying the wiring harness and simplifying assembly. Simultaneously, the horizontal selector adapts to the analog-to-digital converter circuit channels to achieve time-division multiplexing and concurrent sampling, ensuring stable temperature measurement of a large-scale 1024-point array while balancing acquisition efficiency with the advantages of equipment miniaturization and low cost.

[0047] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0048] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0049] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0050] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0051] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0052] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0053] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0054] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0055] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0056] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A temperature detection device for a network scanning surface of temperature sensing elements, characterized in that, include: Power supply; A controllable acquisition point is provided, wherein multiple controllable acquisition points are connected by an array arrangement. Each controllable acquisition point includes a P-channel field-effect transistor (FET) and a temperature-sensing platinum resistance thermometer (RTD). The source of the P-channel FET is connected to the power supply via a pull-up resistor, and the power supply is connected to the gate of the P-channel FET via the pull-up resistor. The drain of the P-channel FET is connected in series with the RTD and then connected to a parallel current sampling output circuit. The gates of all P-channel FETs in the same column are collinear and then connected to the upper end of a voltage divider resistor. A column drive switch is provided, with the controlled terminals of multiple column drive switches respectively connected to the lower terminals of the voltage divider resistors in each column. Each column drive switch includes an N-channel field-effect transistor (FET), the gate of which is connected to a column drive signal, and the source of which is grounded. The column drive signal controls the switching on and off of the N-channel FET. When the column drive switch of a corresponding column is turned on, it pulls down the voltage divider resistor, thereby connecting the controllable acquisition point of the corresponding column to the current sampling output circuit. A current sampling shunt resistor, one end of which is grounded, and all the temperature measuring platinum resistance thermometers in the same row are connected to the other end of the current sampling shunt resistor after their lower ends are collinear. The resistance value of the platinum resistance and the temperature at the measuring point are obtained by calculating the voltage across the resistor of the current sampling shunt.

2. The temperature detection device for a network scanning surface of temperature sensing elements according to claim 1, characterized in that, All controllable acquisition points in the same series share the same current sampling shunt resistor; After all the controllable acquisition points in a row are turned on, the turned-on controllable acquisition points are connected in series and connected to the current sampling shunt resistor to obtain the temperature measurement sampling branch; wherein, the controllable acquisition points in different rows collect the loop current according to their respective current sampling shunt resistors; The loop current of a single temperature sampling branch is sampled by voltage division through the resistor of the current sampling shunt to obtain a sampled voltage signal.

3. The temperature detection device for a network scanning surface of temperature sensing elements according to claim 1, characterized in that, All controllable acquisition points in the same column share a set of voltage divider resistors and the column drive switch; The column drive signal is input to the gate of the N-channel field-effect transistor. The column drive signal controls the conduction of the N-channel field-effect transistor. When the N-channel field-effect transistor is turned on, the gate potential of all the P-channel field-effect transistors in the same column is pulled down by the voltage divider resistor, so that the controllable acquisition points in the same column are synchronously selected.

4. The temperature detection device for a network scanning surface of temperature sensing elements according to claim 1, characterized in that, The gate of each of the P-channel field-effect transistors is connected to an independent pull-up resistor; The other end of the pull-up resistor is connected to the power supply. When the controllable acquisition point is in the disconnected state, the pull-up resistor is used to maintain the gate high level of the P-channel field-effect transistor, so that the P-channel field-effect transistor is in the off state.

5. The temperature detection device for a network scanning surface of a temperature sensing element according to claim 1, characterized in that, It also includes a microcontroller unit digital control circuit board and a front-end gating and acquisition circuit board; The microcontroller digital control circuit board includes multiple general-purpose input / output ports, a filtering circuit, and an analog-to-digital conversion acquisition circuit. The multiple general-purpose input / output ports output column gating control signals and row gating control signals respectively. The column gating control signals and the row gating control signals are transmitted to the front-end gating acquisition circuit board. The column gating control signal and the row gating control signal are processed by the front-end gating acquisition circuit board to perform time-division filtering and channel gating on the sampling voltage signal generated by the current sampling shunt resistor in each row, so as to obtain the current sampling gating output signal. The front-end gating acquisition circuit board transmits the current sampling gating output signal sequentially to the filtering circuit and the analog-to-digital conversion acquisition circuit for filtering and analog-to-digital conversion to obtain a digital voltage value.

6. The temperature detection device for a network scanning surface of temperature sensing elements according to claim 5, characterized in that, The column drive link is formed by the pull-up resistors, the voltage divider resistors, and the N-channel MOSFETs in the same column of the controllable acquisition points. The column-driven link further includes a first-level column selector and a second-level column selector. The first-level column selector is connected to a high-order gating code, and the output of the first-level column selector is connected to multiple groups of second-level column selectors. Each group of second-level column selectors is connected to a low-order gating code. The high-bit gating code and the low-bit gating code are cascaded and decoded by the first-level column gating device and the second-level column gating device to obtain multiple column driving signals.

7. The temperature detection device for a network scanning surface of temperature sensing elements according to claim 6, characterized in that, It also includes a row drive link, in which the temperature measuring platinum resistance, the P-channel field-effect transistor and the current sampling shunt resistor are connected in series to form a row sampling branch, and the row drive link is connected to the output of the row sampling branch; The row drive link includes a first-level row selector and a second-level row selector. The first-level row selector is connected to a high-order gating code, and the output of the first-level row selector is connected to multiple groups of second-level row selectors. Each group of second-level row selectors is connected to a low-order gating code. The first-stage row selector and the second-stage row selector perform concatenated decoding and gating processing on the high-bit gating code and the low-bit gating code to obtain multiple row driving signals. The multiple row driving signals are used to time-division select the row sampling branch and filter the output sampling voltage signal. The second-stage row selector receives the sampled voltage signal. The first-stage row selector generates a selection command based on the row selection control signal and sends the selection command to the second-stage row selector. The second-stage row selector performs time-division initial selection on the sampled voltage signal to obtain multiple sampled output signals. After transmitting the multiple sampled output signals to the first-stage row selector, the multiple sampled output signals are summarized to obtain a current sampling selection output signal. The current sampling selection output signal is output to a filter circuit and an analog-to-digital conversion acquisition circuit for analog-to-digital conversion processing to obtain the digital voltage value.

8. A method for detecting the temperature of a network scanning surface of a temperature sensing element, characterized in that, The temperature detection method for the network scanning surface of the temperature sensing element is applied to the temperature detection device for the network scanning surface of the temperature sensing element as described in claim 7, and the method includes the following steps: The column gating control signal output by the column driving link is configured through the multi-channel general-purpose input / output port to obtain multi-channel column driving logic signals; The column drive logic signal is used to control the on / off state of the column drive switch, so that all the controllable acquisition points of the target column are connected to the sampling circuit, and a single column conduction measurement point array is obtained. The high-bit gating code and low-bit gating code output from the multi-channel general-purpose input / output port are cascaded and decoded by the first-stage row selector and the second-stage row selector to obtain the multi-channel row drive signal. The row selection control signal output by the row drive link is selected and scheduled row by row according to the row drive signal, and each row current sampling branch is selected sequentially according to the single column conduction measurement point array to obtain the sampling voltage signal. The sampled voltage signals are aggregated through the row drive link to obtain the current sampling gating output signal; The current sampling gating output signal is filtered and converted from analog to digital by the filtering circuit and the analog-to-digital conversion acquisition circuit to obtain the digital voltage value. The actual operating current of the circuit is obtained by performing Ohm's law calculation on the digital voltage value based on the nominal resistance of the shunt. The total impedance of the platinum resistance circuit is calculated by converting the voltage of the power supply and the actual operating current of the circuit to obtain the real-time resistance value of the platinum resistance to be tested. The real-time resistance value of the platinum resistance to be measured is converted by looking up a table using the correspondence between the resistance value of the platinum resistance and the temperature, so as to obtain the measured temperature of the controllable acquisition point. The row and column selection combinations of the controllable acquisition points in the array are cyclically switched and calculated separately until the temperature acquisition of all the controllable acquisition points in the array is completed, thereby obtaining the set of platinum resistance data corresponding to all the controllable acquisition points in the array and the set of temperature data of each measurement point.

9. The temperature detection method for a network scanning surface of a temperature sensing element according to claim 8, characterized in that, The process of sequentially selecting and scheduling the row selection control signal output from the row drive link through the multi-channel general-purpose input / output port, and sequentially selecting each row current sampling branch according to the single-column conduction measurement point array to obtain the sampled voltage signal, includes the following steps: The row selection control signal and the column selection control signal output by the microcontroller digital control circuit board are transmitted to the front-end selection acquisition circuit board through a ribbon cable to obtain row and column logic selection signals; The row drive link and the column drive link perform array gating control on the controllable acquisition points according to the row and column logic gating signals to obtain the sampling voltage signal.

10. The temperature detection method for a network scanning surface of a temperature sensing element according to claim 8, characterized in that, The step of configuring column gating control signals output from the column driving link through the multiple general-purpose input / output ports to obtain multiple column driving logic signals includes the following steps: The column selection control signal is output to the column drive link through the multi-channel general-purpose input / output port to complete the column selection configuration. The gate of the P-channel MOSFET that is not selected in the column is pulled up to a high level by the pull-up resistor, so that the controllable acquisition point of the corresponding column remains open. The target column circuit is activated by pulling down the column drive switch, thereby obtaining multiple column drive logic signals.

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