Gas sensor aging test device and electronic nose system

Abstract

The invention relates to the technical field of gas detection, in particular to a gas sensor aging test device and an electronic nose system.The gas sensor aging test device comprises a test cavity, a sensor module, a laminated circuit module and a main control unit; the sensor module is arranged in the test cavity, the sensor module comprises a plurality of sensors, and the plurality of sensors are arranged in an array; the main control unit is electrically connected with the laminated circuit module; the laminated circuit module is electrically connected with the sensor module; wherein the main control unit is used for controlling the laminated circuit module to provide working voltage for the plurality of sensors of the sensor module, and controlling the laminated circuit module to carry out parallel sampling on output signals of the plurality of sensors.

Description

Technical Field

[0001] This disclosure relates to the field of gas detection technology, and in particular to a gas sensor aging test device and an electronic nose system. Background Technology

[0002] With the widespread application of gas sensors in industrial safety monitoring, environmental monitoring, smart homes, and automotive electronics, the consistency and long-term stability of their performance have become key factors affecting product quality and reliability. In traditional production processes, sensor performance is typically stabilized through electrical aging and environmental aging to screen for early failures and assess their lifespan characteristics.

[0003] Currently, common gas sensor aging test methods mainly include constant environment aging, accelerated aging, multi-channel parallel testing systems, and analysis methods combined with data algorithms. Among them, constant environment aging relies on a constant temperature and humidity chamber for long-term stabilization, but it is inefficient and difficult to achieve large-scale synchronous testing; multi-channel parallel testing systems, although increasing the number of channels, are limited by bottlenecks such as gas flow uniformity, signal interference, and environmental consistency; while aging schemes based on dynamic conditions or data-driven approaches are often difficult to apply directly to large-scale production lines due to significant deviations from actual service conditions or insufficient hardware and software integration. Summary of the Invention

[0004] To address the aforementioned technical issues, this disclosure provides a gas sensor aging test apparatus and an electronic nose system.

[0005] On one hand, a gas sensor aging test device is provided, comprising: a test chamber, a sensor module, a stacked circuit module, and a main control unit; the sensor module is disposed in the test chamber, and the sensor module includes multiple sensors arranged in an array; the main control unit is electrically connected to the stacked circuit module; the stacked circuit module is electrically connected to the sensor module; wherein, the main control unit is used to control the stacked circuit module to provide operating voltage to the multiple sensors of the sensor module, and to control the stacked circuit module to perform parallel sampling of the output signals of the multiple sensors.

[0006] In one feasible embodiment, the stacked circuit module includes: an upper circuit board and a lower circuit board; the upper circuit board is a power supply heating drive layer, and is provided with a heating drive circuit; the heating drive circuit is used to provide operating voltage for multiple sensors; the lower circuit board is a signal acquisition layer, and is provided with an analog-to-digital conversion acquisition unit; the analog-to-digital conversion acquisition unit is used to receive the output signals of the multiple sensors and convert the output signals into digital signals; wherein, the upper circuit board and the lower circuit board are connected by connectors, and the upper circuit board and the lower circuit board are grounded and isolated from each other.

[0007] In one feasible embodiment, the sensor module further includes a matrix fixture; the matrix fixture has mounting positions corresponding one-to-one with the plurality of sensors, and each mounting position has a unique number.

[0008] In one feasible embodiment, it further includes: a gas control unit; the test chamber is provided with a gas inlet, a gas outlet and a flow splitting structure; the gas control unit is connected to the gas inlet, and the gas control unit is used to provide a preset gas to the test chamber; the flow splitting structure is disposed between the gas inlet and the sensor module, and is used to make the flow field with uniform flow velocity and concentration distribution when the preset gas flows through the sensor surface of the sensor module.

[0009] In one feasible embodiment, the heating drive circuit includes: multiple constant current drive sub-circuits; for providing heating current to the sensors in different groups or a single sensor; the heating drive circuit is used to receive heating control commands from the main control unit and perform soft start, overcurrent protection and overtemperature protection.

[0010] In one feasible embodiment, the analog-to-digital conversion acquisition unit includes: a plurality of analog-to-digital conversion chips; each of the analog-to-digital conversion chips is used to acquire the output signals of the sensors in different groups or the output signals of a single sensor.

[0011] In one feasible embodiment, the analog-to-digital conversion acquisition unit further includes: a synchronous sampling clock distribution circuit; the synchronous sampling clock distribution circuit is connected to a plurality of the analog-to-digital conversion chips and is used to provide a synchronous sampling clock signal to each analog-to-digital conversion chip.

[0012] In one feasible embodiment, the analog-to-digital conversion acquisition unit further includes: multiple protection circuits; each protection circuit is connected to one of the sensors; the protection circuit includes: an impedance matching resistor and a filter connected in series in the signal path, and a transient voltage suppression device connected in parallel between the output terminal of the filter and the signal ground; the impedance matching resistor is used to limit the input current and achieve impedance matching, the filter is used to filter out high-frequency noise, and the transient voltage suppression device is used to clamp abnormal overvoltage to the signal ground.

[0013] In one feasible embodiment, it further includes: a host computer; the host computer is communicatively connected to the main control unit; the host computer is used to send control commands to the main control unit and receive the output signals of the sensor module and the environmental information of the test cavity.

[0014] On the other hand, an electronic nose system is provided, including: a gas sensor aging test device, wherein the gas sensor aging test device is the gas sensor aging test device in the above embodiments.

[0015] The technical solution provided in this disclosure has the following advantages compared with the prior art: First, by integrating multiple sensors into a single module housed within the cavity and utilizing a stacked circuit module for unified power supply and sampling, a fundamental shift from traditional series aging of single or a small number of sensors to parallel aging of batches of sensors is achieved, significantly shortening the average aging test time per sensor. Furthermore, the main control unit centrally controls the application of the operating voltage and parallel signal sampling, automating and standardizing the aging test process, reducing manual operation steps and the resulting errors, and ensuring consistency between test conditions and data acquisition. Simultaneously, this gas sensor aging test device constitutes a scalable test platform, laying the hardware foundation for subsequent additions of channels, improved control accuracy, and the introduction of environmental control modules, demonstrating excellent scalability. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0017] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a gas sensor aging test device according to some embodiments; Figure 2 This is a schematic diagram of a stacked circuit module according to some embodiments; Figure 3 This is a schematic diagram of another gas sensor aging test apparatus provided according to some embodiments; Figure 4 This is a schematic diagram of the structure of an analog-to-digital conversion acquisition unit according to some embodiments; Figure 5 This is a schematic diagram of another gas sensor aging test apparatus provided according to some embodiments.

[0019] Reference numerals: 1. Test chamber; 2. Sensor module; 21. Sensor; 22. Matrix fixture; 3. Stacked circuit module; 31. Upper circuit board; 312. Heating drive circuit; 3121. Constant current drive sub-circuit; 32. Lower circuit board; 321. Analog-to-digital conversion acquisition unit; 3211. Analog-to-digital conversion chip; 3212. Synchronous sampling clock distribution circuit; 3213. Protection circuit; 4. Main control unit; 5. Gas control unit; 6. Host computer; 100. Gas sensor aging test device; 200. Electronic nose system. Detailed Implementation

[0020] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0021] Throughout this specification and claims, unless the context otherwise requires, the term "comprise" and its other forms, such as the third-person singular "comprises" and the present participle "comprising," are interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific example," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0022] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0023] In this document, the use of “configured to” implies open and inclusive language, which does not exclude devices that are configured to perform additional tasks or steps. The use of “based on” implies openness and inclusivity, because processes, steps, calculations, or other actions “based on” one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0024] "A and / or B" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone. A and B can be singular or plural.

[0025] In describing some embodiments, the term "coupled" and its derivative expressions may be used. For example, the term "coupled" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact. However, the term "coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the content of this document. In describing some embodiments, the term "connected" and its derivative expressions may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact with each other.

[0026] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0027] Existing gas sensor aging test technologies suffer from the following main shortcomings: First, low aging efficiency and limited throughput capacity, failing to match the pace of large-scale production lines; second, uneven distribution of environmental conditions (gas concentration, flow rate, temperature, and humidity) during parallel testing of multiple sensors leads to poor comparability of aging results; third, insufficient dynamic range and accuracy of measurement circuits make it difficult to cover sensor types with wide resistance variations; fourth, significant differences between accelerated aging conditions and actual operating conditions affect the practical reference value of aging data; fifth, a lack of real-time intelligent data processing and anomaly identification capabilities, relying on manual post-processing, resulting in low efficiency; sixth, high system integration and low modularity, leading to complex maintenance and poor usability; seventh, a lack of unified standards for interfaces and protocols hinders the mutual recognition of test results and system promotion; and eighth, high equipment and operating costs restrict deployment and application by small and medium-sized enterprises and R&D institutions.

[0028] Based on this, such as Figure 1 The diagram shown is a structural schematic of a gas sensor aging test apparatus according to some embodiments. The gas sensor aging test apparatus 100 includes: a test chamber 1, a sensor module 2, a stacked circuit module 3, and a main control unit 4.

[0029] Sensor module 2 is installed inside test chamber 1. Sensor module 2 includes multiple sensors 21 arranged in an array. Main control unit 4 is electrically connected to stacked circuit module 3. Stacked circuit module 3 is electrically connected to sensor module 2.

[0030] The main control unit 4 is used to control the stacked circuit module 3 to provide working voltage to the multiple sensors 21 of the sensor module 2, and to control the stacked circuit module 3 to sample the output signals of the multiple sensors 21 in parallel.

[0031] For example, multiple semiconductor gas sensors 21 to be aged are integrated into a sensor module 2, and the sensor module 2 is placed entirely in a sealed test chamber 1.

[0032] A stacked circuit module 3 is connected to the sensor module 2 via a cable, and is used to simultaneously provide the required operating voltage (including heating function) to all sensors 21. A main control unit 4 is connected to the stacked circuit module 3 via a communication and control bus.

[0033] During the aging test, the main control unit 4 sends a unified control command to the stacked circuit module 3 to maintain a stable power supply to all sensors 21. At the same time, the multi-channel acquisition circuit inside the stacked circuit module 3 is configured to simultaneously sample the electrical response signals (such as resistance or current changes) of all sensors 21 synchronously or at high speed, and upload the digitized data to the main control unit 4 for processing and recording, thereby completing the parallel aging and performance monitoring of the entire batch of sensors 21 at once.

[0034] In this way, by integrating multiple sensors 21 into a single cavity module and using the integrated stacked circuit module 3 to achieve unified power supply and signal acquisition, the device realizes the transformation from the traditional single or small number of serial aging to the parallel aging of a batch of sensors 21, which greatly reduces the testing time per unit product.

[0035] Furthermore, the main control unit 4 uniformly controls the application of the working voltage and the parallel sampling of the signal, realizing the automation and standardization of the aging test process, reducing manual operation links and the errors introduced therefrom, and ensuring the consistency of test conditions and data acquisition. At the same time, the gas sensor aging test device 100 constitutes an expandable test platform, laying the hardware foundation for subsequent addition of channels, improvement of control accuracy and introduction of environmental control and other functional modules, demonstrating good scalability.

[0036] Reference Figure 2 In one feasible embodiment, the stacked circuit module 3 includes an upper circuit board 31 and a lower circuit board 32.

[0037] The upper circuit board 31 is a power supply heating drive layer, and a heating drive circuit 312 is provided thereon; the heating drive circuit 312 is used to provide working voltage for multiple sensors 21.

[0038] The lower circuit board 32 is a signal acquisition layer, which is equipped with an analog-to-digital conversion acquisition unit 321. The analog-to-digital conversion acquisition unit 321 is used to receive the output signals of multiple sensors 21 and convert the output signals into digital signals.

[0039] The upper circuit board 31 and the lower circuit board 32 are connected by connectors, and the upper circuit board 31 and the lower circuit board 32 are grounded and isolated from each other.

[0040] The mutual isolation between the grounding of the upper circuit board 31 and the lower circuit board 32 means that the grounding terminals of the upper circuit board 31 and the lower circuit board 32 are different, so they will not affect each other.

[0041] For example, in the stacked circuit module 3 of the gas sensor aging test device 100, two independent printed circuit boards (PCBs) are vertically stacked and fixed by a set of board-to-board connectors (plugs).

[0042] The upper circuit board 31 centrally houses the DC-DC power conversion chip, high-current power traces, MOSFET switch array, and related filter inductors and capacitors, forming a complete heating drive circuit 312. Its output is directly led out through the connector pins to drive the heating wire in the sensor 21.

[0043] The lower circuit board 32 is equipped with a multi-channel operational amplifier, a voltage reference source, a multiplexer, and an analog-to-digital conversion acquisition unit 321, forming a signal conditioning and acquisition link.

[0044] Meanwhile, the upper circuit board 31 and the lower circuit board 32 each have their own independent grounding terminals. The upper circuit board 31 is the power ground, and the lower circuit board 32 is the signal ground. The two are connected at a single point through a ferrite bead or a zero-ohm resistor at the power input port, thereby achieving electrical isolation. During operation, the large current pulse of the upper circuit board 31 will not interfere with the signal acquisition of the sensor 21 by the lower circuit board 32.

[0045] In this way, common ground interference is fundamentally suppressed. By establishing physically separate power ground and signal ground with only a single point connection, the voltage fluctuations generated by the drastically changing large current in the heating circuit on the common ground line are cut off from the transmission path to the sensitive signal reference ground, thus ensuring the stability of the signal measurement reference.

[0046] Meanwhile, the power circuit and the analog-to-digital conversion acquisition unit 321 are placed on different boards, and the ground layer or air medium in between forms a natural shield, which weakens the coupling of the magnetic field and electric field generated by the switching elements and high current loop to the adjacent high impedance signal traces and reduces measurement noise.

[0047] The modular design of the functional partitions allows the power drive and signal acquisition sections to be tested, debugged, and replaced independently. At the same time, the main heat sources (power devices) are concentrated on the upper board, which facilitates centralized heat dissipation design and avoids the heat from affecting the performance of other analog components.

[0048] like Figure 3 As shown, in one feasible embodiment, the sensor module 2 further includes a matrix fixture 22; the matrix fixture 22 is provided with mounting positions corresponding one-to-one with a plurality of sensors 21, and each mounting position has a unique number.

[0049] For example, the matrix clamp 22 of the sensor module 2 has 128 regularly arranged mounting holes in 16 rows × 8 columns. Each hole is embedded with an independent spring pin connector for electrical contact and mechanical fixation with the pins of the sensor under test 21.

[0050] Next to each mounting hole, a unique row and column coordinate number is etched, for example, the first row and first column is identified as A01, the first row and second column as A02, and so on up to P08. When the operator inserts the 128 sensors 21 into the corresponding holes in sequence, each sensor 21 obtains a unique identification in physical space and electrical connection through its coordinate number.

[0051] In this way, the regular matrix arrangement greatly simplifies the layout and organization of the large number of connecting cables from each sensor 21 to the back-end circuit, improving the mechanical reliability and maintenance convenience of the device.

[0052] Meanwhile, the unique number assigned to each installation position binds the abstract sensor 21 to a specific, identifiable physical location. This enables the rapid and accurate location and identification of any sensor 21 during installation, testing, data recording, and even subsequent troubleshooting, completely avoiding management chaos and location errors caused by the large number of sensors 21. Furthermore, this matrix structure with coordinate information provides an intuitive and reliable physical basis for accurately mapping the collected electrical signal data back to each specific sensor 21.

[0053] Reference Figure 3 In one feasible embodiment, the gas sensor aging test device 100 further includes: a gas control unit 5; and the test chamber 1 is provided with a gas inlet, a gas outlet and a flow diversion structure.

[0054] The gas control unit 5 is connected to the gas inlet and is used to provide preset gas to the test chamber 1. The flow splitting structure is set between the gas inlet and the sensor module 2 to make the preset gas flow into a flow field with uniform flow rate and concentration distribution when it flows through the sensor 21 surface of the sensor module 2.

[0055] For example, the gas control unit 5 is used to output a preset gas to the gas inlet of the test chamber 1. Inside the test chamber 1, a gas equalization plate with a large number of micro-pores is connected to the inlet as a flow distribution structure. When the preset gas of preset concentration passes through this equalization plate, it will be dispersed into a large number of uniform and parallel fine micro-flows, which flow upwards parallel to the sensor modules 2 fixed in a planar array, ensuring that the sensitive surface of each sensor 21 is covered. Finally, it is discharged uniformly from the gas outlet at the top of the chamber, thereby forming a gas environment with stable flow rate and consistent concentration in the entire sensor 21 array area.

[0056] This fundamentally ensures the consistency of test conditions: the intake air is actively homogenized by the flow splitting structure (such as the flow equalizer), which effectively eliminates the local flow velocity and concentration differences caused by intake air impact, dead corners in the cavity, or different flow path lengths, so that all sensors 21 in the array are exposed to almost the same target gas atmosphere.

[0057] Meanwhile, the gas control unit 5 allows for precise setting and maintenance of specific gas types, concentrations, and total flow rates. Combined with the stable flow field brought about by the diversion structure, this ensures that the aging environment of each test and each batch of sensors 21 is strictly controllable and highly reproducible, greatly enhancing the standardization level of the testing process and the reliability of experimental data.

[0058] Furthermore, the uniform gas environment avoids systematic errors introduced by the different locations of the sensor 21, making the observed performance changes of the sensor 21 more accurately reflect its own aging characteristics, rather than interference caused by uneven test conditions, thereby improving the accuracy of aging assessment and screening.

[0059] In one feasible embodiment, the heating drive circuit 312 includes a plurality of constant current drive sub-circuits 3121 for providing heating current to different groups of sensors 21 or a single sensor 21.

[0060] The heating drive circuit 312 is used to receive heating control commands from the main control unit 4 and perform soft start, overcurrent protection and overtemperature protection.

[0061] For example, the heating drive circuit 312 consists of 16 identical constant current drive sub-circuit modules 3121. Each sub-circuit module is based on a dedicated constant current drive chip, and its output is connected to a fixed group containing 8 sensors 21 via high-current wires.

[0062] The main control unit 4 sends heating control commands containing target current values ​​to these driver chips via a serial bus. During startup, the commands issued by the main control unit 4 will cause the target current value to rise slowly from zero at a fixed slope (soft start). During operation, the current is continuously monitored, and the output is immediately shut off once the preset threshold is exceeded (overcurrent protection). At the same time, the main control unit 4 will periodically detect the local temperature of the driver chip. If the temperature is too high, it will also command the channel to stop working (overtemperature protection).

[0063] In summary, the soft-start function avoids the thermal shock to the sensitive film of sensor 21 caused by applying a step voltage, thus extending its service life; the real-time overcurrent and overtemperature protection can quickly cut off the fault path, preventing the entire group or even the entire batch of valuable sensors 21 from being damaged due to a short circuit of a single sensor 21 or an abnormal drive circuit, thus ensuring the safety of test assets.

[0064] The design of multiple independent constant current drive sub-circuits 3121 provides a hardware foundation for achieving differentiated and consistent testing, enabling the main control unit 4 to apply different heating powers (currents) to sensors 21 connected to different groups. This allows for aging different models of sensors 21 in the same batch, or applying slightly different stresses to different individuals of the same model to study their dispersion, greatly enhancing the flexibility of the testing strategy.

[0065] The heating conditions are kept stable and reliable over a long period of time: the constant current control of the closed loop of each sub-circuit can automatically compensate for the effects of line resistance, power fluctuations or changes in the resistance of the sensor 21 itself, ensuring that the heating power applied to each sensor 21 or each group of sensors 21 remains highly stable throughout the entire aging cycle of hundreds of hours. This is the key to obtaining repeatable and reliable aging data.

[0066] In one feasible embodiment, the analog-to-digital conversion acquisition unit 321 includes: a plurality of analog-to-digital conversion chips 3211.

[0067] Each analog-to-digital converter chip 3211 is used to acquire the output signals of different groups of sensors 21 or the output signals of a single sensor 21.

[0068] For example, the analog-to-digital conversion acquisition unit 321 is composed of multiple 24-bit analog-to-digital converter chips 3211 of the same model. These analog-to-digital converter chips 3211 are soldered in parallel on a signal acquisition board via pin headers, and each analog-to-digital converter chip 3211 has 8 independent differential input channels.

[0069] During system configuration, the 128 sensors 21 in test chamber 1 are divided into several logical groups using software, for example, into 16 subgroups, with 8 sensors 21 in each group. The 8 output signal lines of each subgroup's sensors 21 are respectively connected to the 8 input channels of an analog-to-digital converter chip 3211. During operation, all analog-to-digital converter chips 3211 synchronously start conversion under the coordination of the main control unit 4, independently and synchronously acquiring the analog voltage signals of the group of sensors 21 they are responsible for, and converting them into digital signals.

[0070] In this way, multiple analog-to-digital converter chips 3211 can simultaneously perform synchronous digital conversion on the signals of a large number of sensors 21, avoiding the time delay and sampling rate reduction problems caused by using a single analog-to-digital converter chip 3211 to sample in turn through a multiplexer. This is suitable for scenarios that require rapid recording of aging transient processes or real-time monitoring.

[0071] Meanwhile, crosstalk and interference between channels are effectively reduced. Each sensor group 21 has an independent analog-to-digital converter chip 3211 for signal processing, physically isolating the direct coupling of analog signal paths between different groups. This reduces crosstalk between channels caused by analog switch leakage and channel switching, ensuring the independence of data acquisition by each sensor 21. Furthermore, it enhances the system's reliability and modularity. The multi-chip distributed architecture reduces the risk of single-point failures; even if one analog-to-digital converter chip 3211 fails, it only affects the sensor group 21 it is responsible for, without paralyzing the entire system's data acquisition function. This chip-based functional division also makes the hardware design more modular, facilitating production, testing, and maintenance.

[0072] Reference Figure 4 In one feasible embodiment, the analog-to-digital conversion acquisition unit 321 further includes a synchronous sampling clock distribution circuit 3212.

[0073] The synchronous sampling clock distribution circuit 3212 is connected to multiple analog-to-digital converter chips 3211 and is used to provide a synchronous sampling clock signal to each analog-to-digital converter chip 3211.

[0074] For example, after precise delay matching and driving, the synchronous sampling clock distribution circuit 3212 generates eight clock signals that are in phase and synchronized with the input clock on its eight output pins. These eight clock signals are transmitted to the external sampling clock input terminals of the eight analog-to-digital converter chips 3211 through PCB traces of equal length, so that all the analog-to-digital converter chips 3211 start sampling and conversion operations at the same physical moment at each rising or falling edge of the clock.

[0075] This ensures data time consistency by distributing a sampling clock from the same source to all analog-to-digital converter chips 3211, eliminating random phase differences in sampling timing caused by each chip using its own internal clock or being triggered by asynchronous signals. It also effectively suppresses measurement noise and errors caused by clock asynchrony. Furthermore, it enhances robustness in interference-prone environments. Compared to the internal frequency division clocks of each chip, a unified external synchronous clock signal is more resistant to power supply noise or environmental electromagnetic interference, ensuring the stability of sampling timing in complex electrical environments and thus maintaining the reliability of the time reference for the entire data acquisition system.

[0076] Reference Figure 4 In one feasible embodiment, the analog-to-digital conversion acquisition unit 321 further includes: multiple protection circuits 3213.

[0077] Each protection circuit 3213 is connected to a corresponding sensor 21; the protection circuit 3213 includes: an impedance matching resistor and a filter connected in series in the signal path, and a transient voltage suppression device connected in parallel between the output of the filter and the signal ground.

[0078] Impedance matching resistors are used to limit input current and achieve impedance matching, filters are used to filter out high-frequency noise, and transient voltage suppression devices are used to clamp abnormal overvoltages to signal ground.

[0079] For example, the analog-to-digital conversion acquisition unit 321 provides a protection circuit 3213 for each signal input channel of the sensor 21. This protection circuit 3213 includes: a 10kΩ resistor as an impedance matching resistor; an RC low-pass filter consisting of a 1kΩ resistor and a 100pF capacitor connected in series in the signal path; and a transient voltage suppression diode, with its cathode connected to the output node of the filter and its anode grounded. In this way, the original output signal of the sensor 21 flows sequentially through the current-limiting resistor and the filter network, while abnormal high-voltage spikes are discharged to ground by the transient voltage suppression diode.

[0080] Since each sensor 21 channel has an independent protection circuit 3213, when any sensor 21 experiences an overcurrent or overvoltage fault due to an internal short circuit, electrostatic discharge, or wiring error, its corresponding impedance matching resistor will immediately limit the fault current, and the transient voltage suppression diode will quickly clamp the voltage, ensuring that the fault is strictly limited within this channel and will not spread through the shared power supply or signal line, thereby avoiding the risk of fault propagation.

[0081] Furthermore, the filter effectively removes high-frequency noise from the sensor 21 itself, the heating circuit, or the environment, providing a stable analog signal for the back-end analog-to-digital converter chip 3211. At the same time, each channel passes through the same protection circuit 3213, ensuring that the signals from all sensors 21 undergo completely consistent signal conditioning and attenuation before entering digitization, avoiding systematic measurement deviations caused by inconsistencies in the front-end circuits, and ensuring the comparability of parallel test results.

[0082] Reference Figure 5 In one feasible embodiment, it further includes: a host computer 6.

[0083] The host computer 6 is connected to the main control unit 4 for communication; the host computer 6 is used to send control commands to the main control unit 4 and receive the output signals of the sensor module 2 and the environmental information of the test chamber 1.

[0084] Through the host computer 6, the complex testing process is made more convenient and automated: users do not need to operate the underlying hardware directly. They can complete the configuration of aging strategies for multiple parameters through the graphical interface of the host computer 6, which greatly reduces the operation threshold and technical risks, and ensures that the testing process is executed automatically in strict accordance with the preset and repeatable program. In addition, the host computer 6 not only receives and visualizes the core performance data of all sensors 21 in real time, but also integrates environmental information (such as temperature and humidity) from the test chamber 1, so that the operator can monitor the status of the entire aging test on a unified platform and promptly discover the correlation between the performance changes of sensor 21 and environmental parameters.

[0085] This application also provides an electronic nose system 200, which includes a gas sensor aging test device 100.

[0086] In some embodiments, this disclosure also provides a vehicle including the electronic nose system 100 described above. The vehicle may be selected from any one of a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV).

[0087] In vehicles, the electronic nose system 200 is used for applications such as in-vehicle air quality monitoring, new energy vehicle battery safety monitoring, personalized smart cockpit experience, supplementing environmental perception in autonomous driving scenarios, and quality control in automobile manufacturing and after-sales service.

[0088] In some embodiments, this disclosure also provides an artificial intelligence device, which includes the electronic nose system 200 described above and a neural network module. The neural network module is configured to generate a gas recognition signal based on the target concentration curve output by the electronic nose system 200.

[0089] In some embodiments, the electronic nose system 200 can also be applied to the field of food safety, for example, in scenarios such as screening the quality and safety of food raw materials, monitoring pollution and quality during processing, grading and identifying the authenticity of finished products, monitoring cold chain transportation and storage environment, and rapid detection and risk warning at the consumer end.

[0090] In some embodiments, the electronic nose system 200 can also be applied to the field of industrial safety. For example, it can be applied to scenarios such as real-time monitoring of industrial waste gas, odor control in water and solid waste treatment, safety control of hazardous chemicals (such as leak emergency response, warehousing and transportation detection and odor concentration detection at the plant boundary), and circular economy and resource utilization.

[0091] In some embodiments, the electronic nose system 200 can also be applied in the field of healthcare. For example, it can be used for screening and diagnosis, infection and complication early warning, personalized medicine and health management (medication effect evaluation and sub-health status monitoring), special group care and assistive medical care, and other scenarios.

[0092] In some embodiments, the electronic nose system 200 can also be applied to the smart home field.

[0093] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A gas sensor aging test device, characterized in that, include: Test chamber, sensor module, stacked circuit module and main control unit; The sensor module is disposed within the test chamber, and the sensor module includes multiple sensors arranged in an array; the main control unit is electrically connected to the stacked circuit module; the stacked circuit module is electrically connected to the sensor module. The main control unit is used to control the stacked circuit module to provide operating voltage to the multiple sensors of the sensor module, and to control the stacked circuit module to sample the output signals of the multiple sensors in parallel.

2. The gas sensor aging test device according to claim 1, characterized in that, The stacked circuit module includes: an upper circuit board and a lower circuit board; The upper circuit board is a power supply heating drive layer, and is provided with a heating drive circuit; the heating drive circuit is used to provide operating voltage for the multiple sensors. The lower circuit board is a signal acquisition layer, and is equipped with an analog-to-digital conversion acquisition unit; the analog-to-digital conversion acquisition unit is used to receive the output signals of the plurality of sensors and convert the output signals into digital signals. The upper circuit board and the lower circuit board are connected by connectors, and the upper circuit board and the lower circuit board are grounded and isolated from each other.

3. The gas sensor aging test device according to claim 2, characterized in that, The sensor module also includes: a matrix clamp; The matrix fixture has mounting positions corresponding to each of the sensors, and each mounting position has a unique number.

4. The gas sensor aging test device according to claim 1, characterized in that, Also includes: Gas control unit; the test chamber is equipped with a gas inlet, a gas outlet, and a flow diversion structure; The gas control unit is connected to the gas inlet, and the gas control unit is used to provide a preset gas to the test chamber; The flow splitting structure is disposed between the gas inlet and the sensor module to create a flow field with uniform flow velocity and concentration distribution when the preset gas flows through the sensor surface of the sensor module.

5. The gas sensor aging test apparatus according to claim 2, characterized in that, The heating drive circuit includes: multiple constant current drive sub-circuits; used to provide heating current to different groups of the sensors or a single sensor; The heating drive circuit is used to receive heating control commands from the main control unit and perform soft start, overcurrent protection and overtemperature protection.

6. The gas sensor aging test apparatus according to claim 2, characterized in that, The analog-to-digital conversion acquisition unit includes: multiple analog-to-digital conversion chips; Each of the analog-to-digital converter chips is used to acquire the output signals of the sensors in different groups or the output signals of a single sensor.

7. The gas sensor aging test apparatus according to claim 6, characterized in that, The analog-to-digital conversion acquisition unit further includes: a synchronous sampling clock distribution circuit; The synchronous sampling clock distribution circuit is connected to multiple analog-to-digital converter chips and is used to provide a synchronous sampling clock signal to each analog-to-digital converter chip.

8. The gas sensor aging test apparatus according to claim 2, characterized in that, The analog-to-digital conversion acquisition unit also includes: multiple protection circuits; Each protection circuit is connected to one of the aforementioned sensors; The protection circuit includes: an impedance matching resistor and a filter connected in series in the signal path, and a transient voltage suppression device connected in parallel between the output terminal of the filter and the signal ground; The impedance matching resistor is used to limit the input current and achieve impedance matching, the filter is used to filter out high-frequency noise, and the transient voltage suppression device is used to clamp abnormal overvoltage to the signal ground.

9. The gas sensor aging test apparatus according to claim 1, further comprising: Host computer; The host computer is communicatively connected to the main control unit; The host computer is used to send control commands to the main control unit and receive the output signals of the sensor module and the environmental information of the test chamber.

10. An electronic nose system, characterized in that, include: The gas sensor aging test apparatus as described in any one of claims 1-9.

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