Batch detection system for gas sensors

Abstract

The invention discloses a batch detection system for gas sensors, and relates to the technical field of sensor detection, and the batch detection system comprises a power supply module which is used for converting an external 12V power supply into a 5V power supply, and providing an adjustable voltage for a gas sensor heating module through an LDO (Low Dropout Regulator) module; the LDO module is used for converting a 5V power supply into a 3.3 V power supply and supplying power to the MCU module, the RS485 communication module and the analog switch module; the MCU module is used for controlling the analog switch module to execute gas sensor selection, collecting detection data of the gas sensor and performing data communication with an upper computer; the RS485 communication module carries out half-duplex communication with an upper computer and other cascade test boards based on an RS485 bus. The dial switch module sets an equipment address for the batch detection system of the gas sensor; the analog switch module is used for selecting a to-be-tested gas sensor according to a row-column scanning mode under the control of the MCU; and the load board is used for providing an adjustable load resistance value. The system improves the detection efficiency of the sensor.

Description

Technical Field

[0001] This invention relates to the field of sensor detection technology, and more specifically to a batch detection system for gas sensors. Background Technology

[0002] Gas monitoring has a wide range of applications in daily life and industrial production. For example, newly renovated homes often release toxic gases such as formaldehyde, which need to be detected by gas detection equipment; real-time detection of methane in kitchens can effectively identify the risk of gas leaks; and in mining environments, monitoring various toxic and harmful gases such as carbon monoxide, sulfur dioxide, nitrogen dioxide, hydrogen sulfide, ammonia, carbon dioxide, methane, and hydrogen is a crucial means of ensuring operational safety. Therefore, various gas sensors are widely used in environmental monitoring, safety protection, and smart homes.

[0003] With the increasing demand for gas monitoring, the market size of gas sensors continues to expand, and the demand for their production is also growing rapidly. In the context of mass production, how to achieve rapid, stable, and reliable testing and screening of a large number of sensors has become a crucial link in the industry chain.

[0004] Current gas sensor batch testing fixtures have several shortcomings: first, the number of sensors that can be tested at one time is limited, which is not conducive to large-scale production needs; second, the cost of the testing fixtures is relatively high and their scalability is poor; third, the testing efficiency is low, manual intervention is high, and the overall production cost is high. These problems directly affect the batch testing efficiency and quality consistency of gas sensors, hindering the industry's large-scale development. Therefore, there is an urgent need for a gas sensor testing system that can achieve multi-channel operation, low cost, high efficiency, and easy scalability to meet current and future large-scale production needs. Summary of the Invention

[0005] The purpose of this invention is to provide a batch testing system for gas sensors. Through the collaborative design of a power supply module, LDO module, MCU module, RS485 communication module, DIP switch module, analog switch module, and load board, it achieves automatic selection, data acquisition, and remote transmission of multiple gas sensors. Specifically, the MCU controls the analog switches to select the sensor under test in a row-column manner, enabling the system to acquire data from multiple sensors on a single board. The RS485 communication module, combined with the address configuration of the DIP switches, allows multiple test boards to cascade on the same bus, significantly improving the system's batch testing capability. The host computer centrally acquires data from all test boards and performs anomaly detection through a unified communication protocol, reducing manual intervention and improving testing efficiency. The power supply module and LDO module provide stable 5V and 3.3V power supplies, and the adjustable LDO provides adjustable voltage for sensor heating, enabling the system to adapt to different types of sensors. Therefore, the cooperation of these modules allows this invention to not only support multi-node, batch, and automated gas sensor testing, but also offers advantages such as simplified wiring, strong scalability, high testing efficiency, and wide adaptability.

[0006] To achieve the above objectives, this invention provides a batch testing system for gas sensors, comprising: a power supply module for converting an external 12V power supply to 5V via DC-DC conversion, and providing an adjustable voltage to the gas sensor heating module via an LDO module; an LDO module for converting the 5V power supply to 3.3V to power an MCU module, an RS485 communication module, and an analog switch module; an MCU module for controlling the analog switch module to select gas sensors, collect gas sensor detection data, and communicate with a host computer via an RS485 communication module; an RS485 communication module for half-duplex communication with the host computer and other cascaded test boards via an RS485 bus; a DIP switch module for setting device addresses for the batch testing system of gas sensors to support multiple test boards operating on the same RS485 bus; an analog switch module for selecting the gas sensor to be tested according to a row and column scanning method under the control of the MCU; and a load board for providing adjustable load resistance to meet the testing requirements of different gas sensors. The host computer collects data from multiple test boards according to the scanning sequence and displays, monitors, and judges anomalies in the collected data.

[0007] In another embodiment, the power module uses a TPS54331DDAR switching power supply chip to convert a 12V input to a 5V output with a maximum output current of 5A.

[0008] In another embodiment, the gas sensor heating power supply uses three LDOs, namely LM1085ISX-ADJ / NOPB, which can provide an adjustable output voltage of 1.25V-15V and a maximum output current of 3A.

[0009] In another embodiment, the LDO module uses three AMS1117-3.3 to convert 5V to 3.3V to power the MCU module, analog switch module and RS485 module.

[0010] In another embodiment, the MCU module uses an N32G455CCL7 microcontroller with a Cortex-M4 core, 512KB Flash, 192KB RAM, 12-bit 1Msps SARADC, and peripheral interfaces such as UART, SPI, and I2C.

[0011] In another embodiment, the RS485 communication module uses the SP3485EEN chip, operates at 3.3V, and features short-circuit protection, over-temperature protection, and low-power shutdown functions.

[0012] In another embodiment, the DIP switch module is a four-way DIP switch used to set 16 different device addresses to support cascading of 16 test boards on the same RS485 bus.

[0013] In another embodiment, the analog switch module uses a 74HC4051PW, a multi-channel analog switch chip with an operating voltage of 2V-10V, a conduction time of 51ns, and an on-resistance of approximately 120Ω.

[0014] In another embodiment, the MCU module selects multiple gas sensors to be tested by controlling the row and column scanning method of the analog switches.

[0015] In another embodiment, the host computer software is used to collect, display, and monitor the gas sensor data of 16 test boards in real time, and to issue a red alarm to indicate the location of the gas sensor when an abnormal value is detected.

[0016] The beneficial effects of this invention are as follows: The batch testing system for gas sensors in this invention includes: a power supply module, used to convert an external 12V power supply to 5V power supply via DC-DC conversion, and to provide an adjustable voltage to the gas sensor heating module through an LDO module; an LDO module, used to convert the 5V power supply to 3.3V to power the MCU module, RS485 communication module, and analog switch module; an MCU module, used to control the analog switch module to perform gas sensor selection, collect gas sensor detection data, and communicate with the host computer via the RS485 communication module; an RS485 communication module, used to perform half-duplex communication with the host computer and other cascaded test boards based on the RS485 bus; a DIP switch module, used to set the device address for the batch testing system of gas sensors to support multiple test boards working on the same RS485 bus; an analog switch module, used to select the gas sensor to be tested according to the row and column scanning method under the control of the MCU; and a load board, used to provide an adjustable load resistance value to meet the testing requirements of different gas sensors; wherein, the host computer is used to collect data from multiple test boards according to the scanning order, and to display, monitor, and judge the anomalies of the collected data. Through the collaborative design of a power supply module, LDO module, MCU module, RS485 communication module, DIP switch module, analog switch module, and load board, the system achieves automatic selection, data acquisition, and remote transmission of multiple gas sensors. Specifically, the MCU controls the analog switches to select the sensor under test in a row-column manner, enabling the system to acquire data from multiple sensors on a single board. The RS485 communication module, combined with the address configuration of the DIP switches, allows multiple test boards to cascade on the same bus, significantly improving the system's batch testing capability. The host computer centrally acquires and diagnoses anomalies from all test boards through a unified communication protocol, reducing manual intervention and improving testing efficiency. The power supply module and LDO module provide stable 5V and 3.3V power supplies, and the adjustable LDO provides adjustable voltage for sensor heating, enabling the system to adapt to different types of sensors. Therefore, the cooperation of these modules allows this invention to not only support multi-node, batch, and automated gas sensor testing, but also offers advantages such as simplified wiring, strong scalability, high testing efficiency, and wide adaptability.

[0017] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a batch detection system for a gas sensor according to an embodiment of this application; Figure 2 This is a circuit diagram of a power supply module according to an embodiment of this application; Figure 3 This is a circuit diagram of a gas sensor heating power supply according to an embodiment of this application; Figure 4 This is a circuit diagram of an LDO module according to an embodiment of this application; Figure 5 This is a circuit diagram of an MCU module according to an embodiment of this application; Figure 6 This is a circuit diagram of an RS485 communication module according to an embodiment of this application; Figure 7 This is a circuit diagram of a DIP switch module according to an embodiment of this application; Figure 8 This is a circuit diagram of an analog switch module according to an embodiment of this application; Figure 9 This is a schematic diagram of the structure of an MCU module that selects multiple gas sensors to be tested by controlling the row and column scanning method of an analog switch, according to an embodiment of this application. Detailed Implementation

[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be noted that references to "an embodiment," "embodiment," "example embodiment," etc., in this specification refer to the described embodiment including specific features, structures, or characteristics; however, not every embodiment must include these specific features, structures, or characteristics. Furthermore, such expressions do not refer to the same embodiment. Moreover, when describing specific features, structures, or characteristics in conjunction with embodiments, whether or not explicitly described, it indicates that incorporating such features, structures, or characteristics into other embodiments is within the knowledge scope of those skilled in the art.

[0020] Furthermore, certain terms are used in the specification and subsequent claims to refer to specific components or parts. Those skilled in the art will understand that manufacturers may use different names or terms to refer to the same component or part. This specification and subsequent claims do not distinguish components or parts by differences in name, but rather by differences in function. The terms "comprising" and "including" used throughout the specification and subsequent claims are open-ended and should be interpreted as "including but not limited to." Additionally, the term "connection" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connections through other systems.

[0021] Please see Figure 1 , Figure 1 This is a schematic diagram of a batch testing system for gas sensors. The system includes: a power supply module for converting an external 12V power supply to 5V via DC-DC conversion and providing adjustable voltage to the gas sensor heating module through an LDO module; an LDO module for converting the 5V power supply to 3.3V to power the MCU module, RS485 communication module, and analog switch module; an MCU module for controlling the analog switch module to select gas sensors, collect gas sensor detection data, and communicate with a host computer via the RS485 communication module; an RS485 communication module for half-duplex communication with the host computer and other cascaded test boards via an RS485 bus; a DIP switch module for setting device addresses for the batch testing system to support multiple test boards operating on the same RS485 bus; an analog switch module for selecting the gas sensor to be tested according to the row and column scanning method under the control of the MCU; and a load board for providing adjustable load resistance to meet the testing requirements of different gas sensors. The host computer collects data from multiple test boards according to the scanning sequence and displays, monitors, and judges anomalies in the collected data.

[0022] Optionally, the power module uses the TPS54331DDAR switching power supply chip to convert a 12V input to a 5V output, with a maximum output current of 5A. The circuit diagram of the power module is shown below. Figure 2 As shown.

[0023] Optional, such as Figure 3 As shown, Figure 3 This is the circuit diagram for the heating power supply of the gas sensor. The heating power supply uses three LDOs, namely LM1085ISX-ADJ / NOPB, which can provide an adjustable output voltage of 1.25V-15V and a maximum output current of 3A.

[0024] Optional, such as Figure 4 As shown, Figure 4 The circuit diagram for the LDO module is shown. The LDO module uses three AMS1117-3.3 converters to convert 5V to 3.3V to power the MCU module, analog switch module, and RS485 module.

[0025] Optional, such as Figure 5 As shown, Figure 5 The circuit diagram is for the MCU module. The MCU module uses the N32G455CCL7 microcontroller, which has a Cortex-M4 core, 512KB Flash, 192KBS RAM, 12-bit 1Msps SAR ADC, and peripheral interfaces such as UART, SPI, and I2C.

[0026] Optional, such as Figure 6 As shown, Figure 6 This is the circuit diagram of the RS485 communication module. The RS485 communication module uses the SP3485EEN chip, operates at a voltage of 3.3V, and has short-circuit protection, over-temperature protection, and low-power shutdown functions.

[0027] Optional, such as Figure 7 As shown, Figure 7 This is the circuit diagram of the DIP switch module. The DIP switch module is a four-way DIP switch used to set 16 different device addresses to support cascading of 16 test boards on the same RS485 bus.

[0028] Optional, such as Figure 8 As shown, Figure 8 The circuit diagram shows the analog switch module, which uses the 74HC4051PW, a multi-channel analog switch chip with an operating voltage of 2V-10V, a conduction time of 51ns, and an on-resistance of approximately 120Ω.

[0029] Optional, such as Figure 9 As shown, Figure 9 This diagram illustrates how the MCU module selects multiple gas sensors to be tested by controlling the row and column scanning of analog switches. For example, if the value of S1 (sensor 1) needs to be tested, a row and column scan can be performed by opening SW1 and SWC1. Since it uses RS485 communication, multiple test boards can be tested through a single bus, reducing the complexity of wiring in the field. The cascading method provides convenience for field expansion and reduction.

[0030] Optionally, the system also includes a host computer. The host computer software is used to collect, display, and monitor the gas sensor data of the 16 test boards in real time, and to issue a red alarm prompt at the corresponding gas sensor location when an abnormal value is detected.

[0031] The above-mentioned gas sensor batch testing system will be described by way of example, using the process of batch testing gas sensors. After power-on, the gas sensor testing system of the present invention first converts the external 12V power supply to 5V output via DC-DC conversion by the power module, and provides a stable 3.3V operating voltage to the MCU module, analog switch module, and RS485 communication module through AMS1117-3.3LDO. At the same time, an adjustable and stable heating voltage is provided to the heating end of the gas sensor through three adjustable LDOs (LM1085). According to the requirements of different sensors, the heating voltage is set by adjusting the resistor, thereby enabling the sensor to enter the normal working state.

[0032] After the power supply stabilizes, the MCU module begins operation. The multi-channel ADC, operational amplifier, and communication peripherals integrated within the MCU provide the hardware foundation for subsequent data acquisition. During system initialization, the MCU first reads the address information set by the DIP switch to determine the unique communication address of this test board in the RS485 bus, ensuring that communication with the host computer and other test boards will not conflict.

[0033] Subsequently, the MCU controls the selection port of the analog switch module (74HC4051) to select the gas sensor to be detected using a row and column scanning method. For example, when data from sensor S1 needs to be acquired, the MCU outputs a corresponding control signal to open SW1 and SWC1, connecting the output port of S1 to the MCU's ADC input. Because the analog switch supports high-speed switching and multiple selection, the MCU can poll all sensors sequentially in a preset order to complete multi-channel detection.

[0034] After the sensor is selected, the MCU's internal 12-bit, 1Msps high-speed SARADC samples the sensor's output voltage. The acquired analog signal is converted into a digital signal by the ADC, and then the MCU performs preliminary processing, such as filtering, averaging, or data formatting. The processed data, along with the current sensor channel number and test board address, is packaged and sent to the host computer via the RS485 communication module.

[0035] On the RS485 bus, since each test board has an independent address and uses half-duplex communication mode, the host computer can collect data from all test boards one by one by polling or broadcasting according to the address. The host computer maps the received sensor data to the actual sensor positions according to the scanning order and displays it on the interface in real time. If the host computer determines that a certain data exceeds the set normal range, it will mark the corresponding sensor position with a red alarm, so that production personnel can quickly screen out unqualified sensors.

[0036] As the MCU continuously controls the analog switches to poll different sensors, collect data, and send it, the host computer can achieve continuous, high-speed, and batch testing of multiple test boards, each with multiple sensors. Because the system uses an RS485 bus structure, the test boards can be cascaded, thus enabling flexible expansion of the number of tests, simplified wiring, and improved efficiency.

[0037] In summary, by providing stable power supply through a power module, selecting sensors through analog switches, acquiring and processing data through an MCU, uploading data via RS485, and centrally displaying and filtering data on a host computer, this invention achieves an automated, batch-processing, and highly efficient detection process for gas sensors.

[0038] The gas sensor batch testing system in the above embodiments includes: a power supply module for converting an external 12V power supply to 5V via DC-DC conversion, and providing an adjustable voltage to the gas sensor heating module through an LDO module; an LDO module for converting the 5V power supply to 3.3V to power the MCU module, RS485 communication module, and analog switch module; an MCU module for controlling the analog switch module to select gas sensors, collect gas sensor detection data, and communicate with a host computer via an RS485 communication module; an RS485 communication module for half-duplex communication with the host computer and other cascaded test boards via an RS485 bus; a DIP switch module for setting device addresses for the gas sensor batch testing system to support multiple test boards operating on the same RS485 bus; an analog switch module for selecting the gas sensor to be tested according to the row and column scanning method under the control of the MCU; and a load board for providing adjustable load resistance to meet the testing requirements of different gas sensors. The host computer collects data from multiple test boards according to the scanning sequence and displays, monitors, and judges anomalies in the collected data. Through the collaborative design of a power supply module, LDO module, MCU module, RS485 communication module, DIP switch module, analog switch module, and load board, the system achieves automatic selection, data acquisition, and remote transmission of multiple gas sensors. Specifically, the MCU controls the analog switches to select the sensor under test in a row-column manner, enabling the system to acquire data from multiple sensors on a single board. The RS485 communication module, combined with the address configuration of the DIP switches, allows multiple test boards to cascade on the same bus, significantly improving the system's batch testing capability. The host computer centrally acquires and diagnoses anomalies from all test boards through a unified communication protocol, reducing manual intervention and improving testing efficiency. The power supply module and LDO module provide stable 5V and 3.3V power supplies, and the adjustable LDO provides adjustable voltage for sensor heating, enabling the system to adapt to different types of sensors. Therefore, the cooperation of these modules allows this invention to not only support multi-node, batch, and automated gas sensor testing, but also offers advantages such as simplified wiring, strong scalability, high testing efficiency, and wide adaptability.

[0039] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0040] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A batch detection system for gas sensors, characterized in that, The system includes: The power module is used to convert an external 12V power supply to 5V power supply via DC-DC conversion, and to provide an adjustable voltage to the gas sensor heating module through the LDO module; The LDO module is used to convert the 5V power supply to 3.3V to power the MCU module, RS485 communication module and analog switch module; The MCU module is used to control the analog switch module to select the gas sensor, collect the detection data of the gas sensor, and communicate with the host computer via the RS485 communication module. The RS485 communication module is used for half-duplex communication with the host computer and other cascaded test boards based on the RS485 bus. The DIP switch module is used to set the device address for the batch testing system of gas sensors, so as to support multiple test boards to work on the same RS485 bus. The analog switch module is used to select the gas sensor to be tested according to the row and column scanning method under the control of the MCU; Load board, used to provide adjustable load resistance to meet the testing requirements of different gas sensors; The host computer is used to collect data from multiple test boards according to the scanning order, and to display, monitor and judge the collected data.

2. The batch detection system for gas sensors as described in claim 1, characterized in that, The power module uses a TPS54331DDAR switching power supply chip to convert a 12V input to a 5V output, with a maximum output current of 5A.

3. The batch detection system for gas sensors as described in claim 2, characterized in that, The gas sensor heating power supply uses three LDOs, namely LM1085ISX-ADJ / NOPB, which can provide an adjustable output voltage of 1.25V-15V and a maximum output current of 3A.

4. The batch detection system for gas sensors as described in claim 2, characterized in that, The LDO module uses three AMS1117-3.3 converters to convert 5V to 3.3V, providing power to the MCU module, analog switch module, and RS485 module.

5. The batch detection system for gas sensors as described in claim 1, characterized in that, The MCU module uses an N32G455CCL7 microcontroller, which has a Cortex-M4 core, 512KB Flash, 192KB RAM, 12-bit 1Msps SAR ADC, and peripheral interfaces such as UART, SPI, and I2C.

6. The batch detection system for gas sensors as described in claim 5, characterized in that, The RS485 communication module uses the SP3485EEN chip, operates at 3.3V, and features short-circuit protection, over-temperature protection, and low-power shutdown functions.

7. The batch detection system for gas sensors as described in claim 1, characterized in that, The DIP switch module is a four-way DIP switch used to set 16 different device addresses to support cascading of 16 test boards on the same RS485 bus.

8. The batch detection system for gas sensors as described in claim 7, characterized in that, The analog switch module uses the 74HC4051PW, a multi-channel analog switch chip with an operating voltage of 2V-10V, a conduction time of 51ns, and an on-resistance of approximately 120Ω.

9. The batch detection system for gas sensors as described in claim 7, characterized in that, The MCU module selects multiple gas sensors to be tested by controlling the row and column scanning method of the analog switch.

10. The batch detection system for gas sensors as described in claim 1, characterized in that, The host computer software is used to collect, display, and monitor the gas sensor data of 16 test boards in real time, and to issue a red alarm prompt at the corresponding gas sensor location when an abnormal value is detected.

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