Modularized high-precision nixie tube display instrument

Abstract

The utility model relates to the technical field of display instruments, in particular to a modularized high-precision nixie tube display instrument which comprises an instrument frame, a main control board and a plurality of nixie tubes arranged on the instrument frame, and each nixie tube is provided with an independent nixie tube control circuit board. According to the utility model, the display rule can be flexibly adjusted, and the digital display device is used for high-precision display of key numerical values and parameters in places such as large factories and halls.

Description

Technical Field

[0001] This utility model relates to the field of display instrument technology, specifically to a modular high-precision digital tube display instrument. Background Technology

[0002] In large factories and control rooms, there is a critical need for accurate and clear display of key values ​​and parameters. Existing display instruments have limitations in terms of bit expansion, signal compatibility, and display accuracy. For example, some display instruments use a fixed-bit display method, making it difficult to flexibly adjust the number of bits according to actual needs, forcing the replacement of the entire display unit when the display range needs to be expanded. Simultaneously, existing instruments have significant shortcomings in signal processing, particularly in analog signal acquisition and conversion. The lack of high-precision signal conditioning circuits and AD conversion modules makes them prone to signal attenuation and interference, leading to decreased display accuracy. Furthermore, traditional display instruments typically use a centralized driving method, where digital tubes interfere with each other; a failure in one digital tube affects the overall display effect. These deficiencies make existing display instruments unable to meet the high requirements of data accuracy and display flexibility in industrial applications, especially in automated systems requiring remote monitoring and data interaction. Utility Model Content

[0003] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a modular high-precision digital tube display instrument.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a modular high-precision digital tube display instrument, comprising an instrument frame, a main control board, and multiple digital tubes arranged on the instrument frame, each of which is provided with an independent digital tube control circuit board, and all digital tube control circuit boards are connected to the main control board.

[0005] In some embodiments, the main control board includes a power module, a main control module, an AD sampling module, and a communication module. The power module converts the external input voltage into multiple stable output voltages to power each functional module. The main control module is connected to the digital tube control circuit board, the AD sampling module, and the communication module via a bus to realize data processing and control command issuance. The AD sampling module is used to collect external analog signals and convert them into digital signals for processing by the main control module. The communication module is used to interact with external devices.

[0006] In some embodiments, the power module includes a multi-stage conversion circuit for 24V to 12V, 12V to 5V, and 5V to 3.3V.

[0007] In some embodiments, the digital tube control circuit board is a digital tube driver module using the TM1637 chip.

[0008] In some embodiments, the AD sampling module includes a front-end signal conditioning circuit, an ADC chip, and a 2.5V reference voltage source; the front-end signal conditioning circuit uses an INA826AIDR precision amplifier, the ADC chip communicates with the main control module through an SPI interface, and the sampled data is output to the main control module after digital filtering.

[0009] In some embodiments, the communication module employs an RS485 half-duplex communication interface.

[0010] In some embodiments, the main control module uses an STM32F103C8T6 microcontroller.

[0011] In some embodiments, the digital tube is a large-size 7-segment digital tube.

[0012] Compared with the prior art, the advantages of this utility model are: the modular design enables flexible expansion of the number of display bits, the independent control circuit avoids the impact of single-point failure on the overall display, and the combination of high-precision signal processing ensures data accuracy. It has the advantages of modular structure for flexible expansion of the number of display bits, independent control circuit for improved reliability, and high-precision signal processing capability.

[0013] Details of one or more embodiments of this application are set forth in the following drawings and description to make other features, objects and advantages of this application more readily apparent. The embodiments of this application will provide a detailed description and understanding of the application. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 ;

[0015] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 ;

[0016] Figure 3 This is a schematic diagram of the module connection principle of this utility model;

[0017] Figure 4 This is the circuit schematic diagram of this utility model;

[0018] Figure 5 for Figure 4 The schematic diagram of the main control module circuit in the middle;

[0019] Figure 6 for Figure 4 The schematic diagram of the power module circuit in the middle;

[0020] Figure 7 for Figure 4 The schematic diagram of the digital tube control circuit in the image;

[0021] Figure 8 for Figure 4 The schematic diagram of the AD sampling module circuit in the image;

[0022] Figure 9 for Figure 4 The circuit schematic of the communication module in the diagram.

[0023] In the diagram: 1. Instrument frame; 2. Digital tube; 3. Digital tube control circuit board; 4. Digital tube control circuit board connection interface; 5. Main control board; 6. Main control board external connection interface; 7. Main control board control buttons. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] In existing technologies, large industrial environments face challenges in displaying key parameters due to difficulties in expanding the number of digits, poor signal compatibility, and insufficient accuracy. Traditional display instruments employ an integrated circuit design, with the digital tube and control circuit fixedly integrated. This necessitates redesigning the hardware to adjust the number of digits, making it inflexible for adapting to different scenarios. Excessive signal conversion steps also introduce noise interference, affecting the accuracy of the final displayed value.

[0026] To address these issues, researchers discovered that the integrated design of the digital display and control circuit in existing technologies is a key factor limiting scalability. Analysis of the signal transmission path revealed that multiple conversion stages lead to error accumulation. Based on this, a proposal was made to decouple the digital display from the drive circuit, employing an independent control unit to achieve a modular layout. Simultaneously, the interaction between the main control board and each module was optimized to reduce signal conversion levels.

[0027] Therefore, this application proposes a modular high-precision digital tube display instrument, including an instrument frame, a main control board, and multiple digital tubes arranged on the instrument frame. Each digital tube is equipped with an independent digital tube control circuit board, and all digital tube control circuit boards are connected to the main control board.

[0028] The instrument frame refers to the mechanical structure that supports the main control board and digital tube components. It can be constructed using aluminum alloy profiles and has standardized mounting slots for fixing digital tube modules of different sizes. The main control board is the core circuit unit that coordinates the operation of each module. It can be a multi-layer PCB board integrating power management, data processing, and communication interfaces, interacting with external devices via a bus protocol. The digital tube is a light-emitting device used for numerical display, specifically a common-anode seven-segment display, with its common anode terminal connected to the drive circuit via a current-limiting resistor. The digital tube control circuit board is the drive module that independently controls the display of each individual digital tube. It can be implemented using a dynamic scanning drive chip, synchronizing data refresh with the main control board via a clock signal.

[0029] Specifically, the standardized slots in the instrument frame allow for rapid addition or removal of the number of digital tubes. Each digital tube is connected to the main control board via an independent control circuit board, forming a star topology. When the main control board sends display data to each control circuit board, a time-division multiplexing mechanism is used to avoid signal conflicts. The independent control circuit board locally buffers the received data and converts it into drive current to control the illumination of each segment of the digital tube. This structure eliminates the signal attenuation problem in traditional cascaded circuits, while ensuring that the failure of a single digital tube does not affect the overall operation.

[0030] Compared to existing technologies, traditional solutions involve a fixed binding between the digital tubes and the control circuit, requiring a complete replacement for any hardware expansion. This solution, through modular design, allows for flexible configuration of the number of digital tubes based on site requirements, and the independent control circuit board reduces the complexity of signal transmission paths. The distributed architecture of the main control board and driver module reduces data processing pressure and avoids the response delays associated with centralized control.

[0031] Through the above technical solution, this application achieves flexible expansion of the display digit count, adapting to the differentiated requirements of parameter digit count in different industrial scenarios. The independent drive module reduces signal conversion steps, effectively suppresses noise interference, and improves the accuracy of displayed values. The modular structure simplifies the maintenance process; in the event of a single digital tube failure, the corresponding module can be directly replaced without stopping the entire instrument for repair.

[0032] This application further proposes a main control board comprising a power supply module, a main control module, an AD sampling module, and a communication module. The power supply module is used to convert the external input voltage into multiple stable output voltages to power each functional module. The main control module is connected to the digital tube control circuit board, the AD sampling module, and the communication module via a bus to realize data processing and control command issuance. The AD sampling module is used to acquire external analog signals and convert them into digital signals for processing by the main control module. The communication module is used to interact with external devices.

[0033] The power supply module is a circuit system that performs multi-stage conversion of the external input voltage. Specifically, it can use an LM2596S-5.0 switching regulator and an AMS1117-3.3 linear regulator to achieve multi-stage voltage conversion, and integrate overvoltage protection, overcurrent protection, and filtering circuits to ensure power supply stability. The main control module is a microcontroller that coordinates the operation of various functional modules. Specifically, it can use an STM32F103C8T6 chip to implement bus communication and control command issuance, and connect to other modules through GPIO, SPI, and UART interfaces. The AD sampling module is a circuit unit that converts analog signals to digital signals. Specifically, it can use an AD7793 chip combined with a precision amplifier to achieve high-precision signal conversion. The communication module is an interface unit that enables external data exchange. Specifically, it can use a MAX3485EESA chip to build an RS485 communication link, and integrate TVS diodes and a resettable fuse to enhance anti-interference capabilities.

[0034] Specifically, the main control board uses a power module to progressively convert the externally input 24V voltage to 12V, 5V, and 3.3V, providing a stable power supply for the digital tube driver, AD sampling, and communication modules. The main control module sends display commands to the digital tube control circuit board via a bus, simultaneously receives the digital signals converted by the AD sampling module for data processing, and exchanges data with external devices through the communication module. The AD sampling module uses a precision amplifier to condition the input ±10V differential signal, and then uses a 24-bit Σ-Δ ADC chip to complete the analog-to-digital conversion, ensuring measurement accuracy. The communication module uses an RS485 interface with the Modbus RTU protocol to achieve reliable data transmission between multiple devices.

[0035] This solution utilizes multi-stage voltage conversion and bus connectivity to enable the main control module to efficiently coordinate various functional modules. Simultaneously, the high-resolution conversion capability of the AD sampling module addresses the insufficient signal accuracy of traditional instruments. Furthermore, the anti-interference design of the communication module overcomes the vulnerability of signal transmission to interference in industrial environments.

[0036] Through the above technical solutions, this application achieves multi-voltage compatible power supply and modular control for display instruments, solving the shortcomings of existing equipment in signal conversion accuracy, anti-interference capability, and system scalability. The bus architecture of the main control module improves data processing efficiency, the high-precision conversion of the AD sampling module ensures the accuracy of measurement data, and the protective design of the communication module enhances reliability in industrial environments, thereby meeting the needs of large factories for high-precision display and stable transmission of key parameters.

[0037] This application further proposes a power module including a multi-stage conversion circuit for 24V to 12V, 12V to 5V, and 5V to 3.3V. Each stage of the conversion circuit integrates overvoltage protection, overcurrent protection, and filtering circuits. Specifically, the 24V to 12V conversion uses an LM2596S-5.0 switching regulator, the 12V to 5V conversion uses an AMS1117-3.3 linear regulator, and the 5V to 3.3V conversion uses an AMS1117-3.3 linear regulator. Each stage output is equipped with a decoupling capacitor to suppress power supply ripple and ensure output voltage stability ≤ ±0.5%.

[0038] The multi-stage conversion circuit refers to a power supply architecture that progressively reduces the input voltage in stages. Specifically, an LM2596S-5.0 switching regulator can be used to convert 24V to 12V, and an AMS1117-3.3 linear regulator can be used to convert 12V to 5V and 5V to 3.3V. Voltage division reduces heat loss in each stage. Overvoltage protection refers to a circuit-breaking protection mechanism triggered by a voltage detection circuit. Overcurrent protection refers to the abnormal load disconnection achieved through a combination of a current sampling resistor and a comparator. The filter circuit refers to a low-pass filter composed of LC components, used to eliminate high-frequency noise. Decoupling capacitors are combinations of ceramic and electrolytic capacitors connected in parallel at the power output, such as a 100nF ceramic capacitor and a 10μF electrolytic capacitor connected in parallel, used to absorb high-frequency and low-frequency ripple interference.

[0039] Specifically, the externally input 24V DC power supply is converted to 12V by an LM2596S-5.0 switching regulator, and then further converted to 5V and 3.3V in two stages by an AMS1117-3.3 linear regulator. Each conversion circuit includes an overvoltage protection module to monitor whether the output voltage exceeds a threshold, and an overcurrent protection module to monitor the load current in real time, immediately cutting off the power supply when an abnormality is detected. The filtering circuit uses a combination of inductors and capacitors to filter out high-frequency noise generated by the switching regulator, and decoupling capacitors further eliminate residual ripple. Through multi-stage conversion and multiple protection mechanisms, a stable power supply voltage is ensured for all functional modules on the main control board.

[0040] This solution reduces the stress on single-stage circuits through a multi-stage conversion architecture, and integrates overvoltage, overcurrent protection and filtering circuits, which can effectively suppress power supply noise and improve system reliability.

[0041] Through the above technical solution, this application solves the problem of decreased display accuracy caused by power fluctuations in existing display instruments. The stable multi-level power supply architecture ensures the working voltage accuracy of the AD sampling module and the digital tube drive module. At the same time, the modular power supply design facilitates maintenance and fault isolation, improving the long-term operational reliability of the instrument in industrial environments.

[0042] This application further proposes that the digital tube control circuit board is a digital tube driver module using the TM1637 chip. The TM1637 chip supports dynamic scanning drive. Its SEG1-SEG8 pins are connected to the segment selection terminals of the 8-digit common anode digital tube, and the GRID1-GRID6 pins are connected to the digit selection terminals. The main control module sends timing instructions to the TM1637 through the CLK and DIO interfaces. In the driver circuit, the segment selection signal is connected in series with a current-limiting resistor, and the digit selection signal is amplified by a transistor to control the cathode of the digital tube, ensuring that the dynamic scanning frequency is ≥50Hz to avoid visual flicker.

[0043] The TM1637 chip refers to a control chip with integrated driver circuitry. It can be implemented using an integrated circuit with dynamic scanning capabilities, reducing pin count and power consumption through time-division multiplexing. The segment selection terminal is the signal interface that controls the illumination of each segment of the digital tube. This is achieved by connecting the chip's output pin to the anode of the digital tube, selecting the segment to be illuminated. The digit selection terminal is the signal interface that controls the digit selection of the digital tube. This is achieved by connecting the chip's output pin to the cathode of the digital tube, selecting the digit to be illuminated. The current-limiting resistor is a resistor connected in series in the segment selection signal path, typically a 47kΩ resistor, used to limit current and protect the chip and the digital tube. Transistor amplification enhances the driving capability of the digit selection signal using semiconductor devices, typically an MMBT3904 transistor, providing sufficient current to control the switching of the digital tube cathode. A dynamic scanning frequency of ≥50Hz refers to the minimum switching rate of the digit selection signal, achieved by adjusting the chip's scanning cycle parameters, to eliminate perceptible flicker.

[0044] Specifically, the TM1637 chip drives multiple digital tubes in a time-division multiplexing manner using dynamic scanning. The main control module sends display data to the chip's CLK and DIO interfaces. The segment selection signal is connected to the anode of the digital tube through a current-limiting resistor, and the digit selection signal is amplified by a transistor to control the cathode's on / off state. The chip cycles through the digit selection signal at a set frequency, causing each digital tube to light up sequentially, achieving stable display by utilizing the persistence of vision in the human eye.

[0045] This solution simplifies the driving circuit by integrating the TM1637 chip, and combines dynamic scanning and transistor amplification design to reduce hardware costs while improving display refresh efficiency and effectively avoiding visual flicker.

[0046] Through the above technical solution, this application solves the problems of poor display stability and visual flicker caused by the complex design of the driving circuit in existing display instruments. By optimizing the signal driving method and scanning frequency control, a highly reliable multi-digit LED display is achieved, meeting the needs of clear and flicker-free display in industrial environments.

[0047] This application further proposes an AD sampling module including a front-end signal conditioning circuit, a 24-bit Σ-Δ ADC chip, and a 2.5V reference voltage source; the front-end signal conditioning circuit adopts an INA826AIDR precision amplifier, supports ±10V differential input, and converts external 0-20mA / 4-20mA current signals or 0-10V voltage signals into 0-3.3V voltage signals through a resistor divider network; the ADC chip communicates with the main control module through an SPI interface, and the sampled data is output to the main control module after digital filtering.

[0048] The front-end signal conditioning circuit refers to the preprocessing unit used for signal amplitude adaptation. Specifically, it can be implemented using a circuit structure including a precision operational amplifier, converting industrial signals of different ranges into voltage ranges suitable for the ADC chip by adjusting the voltage division ratio. The 24-bit Σ-Δ ADC chip is an analog-to-digital converter with high-resolution characteristics, specifically implemented using a conversion architecture based on oversampling technology, effectively suppressing high-frequency noise through integral quantization. The 2.5V reference voltage source is a circuit element providing a stable reference voltage, specifically implemented using a reference chip with a low temperature drift coefficient, establishing an accurate voltage reference for the ADC conversion process. The SPI interface is a synchronous serial communication protocol, specifically implemented using a four-wire master-slave communication method, achieving high-speed data transmission through clock signal synchronization. Digital filtering refers to the algorithmic processing of sampled data to suppress noise, specifically implemented using a moving average algorithm, eliminating random interference by superimposing data from multiple periods.

[0049] Specifically, when the analog signal output from the external sensor enters the AD sampling module, the amplitude is first adapted by the front-end signal conditioning circuit. For 0-20mA current signals, a precision resistor network converts them into voltage signals; for 0-10V voltage signals, a voltage divider circuit attenuates the signal. The conditioned signal is then input to the 24-bit ADC chip for analog-to-digital conversion. During the conversion, a reference voltage source provides a stable reference for the chip. The converted data is transmitted to the main control module via the SPI bus. During transmission, a moving average algorithm is used to smooth the data, eliminating the impact of high-frequency noise on measurement accuracy.

[0050] This solution employs a 24-bit high-precision ADC in conjunction with a precision reference source, significantly improving signal quantization accuracy. Simultaneously, the front-end conditioning circuit, through a configurable voltage divider network design, achieves compatible processing of various industrial standard signals, overcoming the shortcomings of traditional instruments that require external signal conversion modules.

[0051] Through the above technical solution, this application effectively solves the adaptation problem when multiple types of signals are accessed in industrial sites, achieving high-precision data acquisition while maintaining system integration. The combination of precision amplification circuit and high-resolution ADC significantly improves the detection capability of weak signals, while digital filtering algorithm effectively suppresses the influence of electromagnetic interference on measurement results, ensuring that the displayed data accurately reflects the actual operating parameters.

[0052] This application further proposes that the communication module adopts an RS485 half-duplex communication interface, with the core chip being MAX3485EESA; the interface circuit integrates a TVS diode and a self-resetting fuse for surge suppression and short-circuit protection; the communication signal is shaped by an RC low-pass filter network and then connected to the main control module through a UART interface, supporting the Modbus RTU protocol, with a communication rate configurable from 9600 to 115200 bps.

[0053] The RS485 half-duplex communication interface is an industry-standard interface based on differential signal transmission, which can be implemented using the MAX3485EESA chip. This chip has electromagnetic interference resistance and supports multi-point bus topology. TVS diodes are transient voltage suppression devices, specifically the SM712 model, used to absorb surge voltages in communication lines. Resettable fuses are polymer components with overcurrent protection, specifically the PTC1206 model, which automatically resumes conduction after a short-circuit fault is cleared. The RC low-pass filter network is a filter circuit composed of resistors and capacitors, specifically implemented using a 100Ω resistor and a 100pF capacitor in series, used to filter out high-frequency noise interference. The Modbus RTU protocol is a common serial communication protocol in the industrial field, specifically implemented using binary encoding format, supporting data read and write operations between master and slave devices.

[0054] Specifically, in large factory environments, the communication module establishes a connection with a host computer or other devices via an RS485 interface. When external interference signals enter the communication line, TVS diodes clamp transient overvoltages to a safe range, and a resettable fuse cuts off the circuit upon detecting overcurrent, preventing chip burnout. After the communication signal passes through an RC filter network, high-frequency noise components are attenuated, and the waveform is shaped. The main control module sends data frames conforming to the Modbus RTU protocol to the MAX3485EESA chip via a UART interface. The communication rate can be set to any value between 9600bps and 115200bps according to field requirements; for example, the rate can be reduced to improve stability during long-distance transmission.

[0055] This solution significantly improves the surge protection capability and system reliability of the communication line by employing an RS485 interface with differential transmission characteristics, combined with a multi-level protection mechanism of TVS diodes and self-resetting fuses. Simultaneously, the introduction of an RC filter network effectively suppresses high-frequency noise during signal transmission, resulting in a marked improvement in data frame integrity compared to solutions without filter circuitry.

[0056] Through the above technical solution, this application solves the problem of communication interruption caused by electromagnetic interference and line faults in industrial environments, achieving the goal of stable data transmission and display in complex electromagnetic environments. The configurable communication rate design allows the instrument to adapt to application scenarios with different transmission distances, while standardized support for the Modbus protocol enhances the compatibility of the device with various control systems.

[0057] This application further proposes that the main control module adopts an STM32F103C8T6 microcontroller, which integrates GPIO, SPI, UART, and I2C peripheral interfaces; the PA port is connected to the CLK and DIO pins of the digital tube driver module, the PB port is connected to the control pins of the AD sampling module, and the PC port is connected to the transmit and receive pins of the RS485 communication module; it has a built-in watchdog timer and low-power mode, and supports external interrupt wake-up and power-down detection.

[0058] The STM32F103C8T6 microcontroller is an embedded control chip based on the ARM Cortex-M3 core, specifically implemented in an LQFP48 package. It achieves physical layer communication with various functional modules through integrated peripheral interfaces. The GPIO interface refers to general-purpose input / output ports, specifically using pins PA0-PA15 to transmit timing signals for the digital tube driver module, used for dynamically controlling the content displayed on the digital tube. The watchdog timer is a hardware-level system monitoring unit, specifically implemented using a window watchdog module, used to automatically reset the main control module to maintain system stability in case of program abnormalities. Low-power mode refers to a working state that reduces power consumption by shutting down unnecessary peripherals, specifically implemented using a sleep mode and stop mode switching mechanism, used to reduce power consumption when there are no data updates.

[0059] Specifically, the main control module outputs the CLK clock signal and DIO data signal through the PA port of the GPIO interface to drive the digital tube control circuit board to refresh the display content; the chip select and reset signals output from the PB port control the AD sampling module to start data conversion and calibration operations; the UART transceiver pin of the PC port is connected to the RS485 communication module to realize the reception and transmission of Modbus protocol data packets. When the system is idle, the main control module automatically enters a low-power mode, which is triggered by an external interrupt signal or a power failure detection circuit to wake up and resume real-time data processing functions. The watchdog timer continuously monitors the main program's running cycle and performs a system restart operation when it detects that the timeout has not been reset.

[0060] This solution utilizes a microcontroller with multiple interface resources, enabling simultaneous operation of the digital tube module, AD sampling module, and communication module without requiring additional expansion circuitry. The built-in watchdog timer effectively resolves program crashes caused by electromagnetic interference in industrial environments, while the low-power mode significantly reduces energy consumption in standby mode.

[0061] Through the above technical solutions, this application achieves a high degree of integration and improved operational reliability of the display instrument main control system, solving the problems of insufficient interface resources, poor system stability, and excessive energy consumption in traditional solutions. Digital tube display control, analog signal acquisition, and communication functions can be completed under a single chip architecture, reducing hardware design complexity. The automatic recovery mechanism in abnormal system states reduces the need for manual maintenance, and the low power consumption extends the continuous operating time of the equipment in scenarios without external power supply.

[0062] This application further proposes that the digital tube be a large-size 7-segment digital tube.

[0063] Among them, the large-size 7-segment digital tube refers to a display device with a single segment height exceeding the conventional size. Specifically, it can be implemented using a common anode structure with a segment height of 50 mm. Its light-emitting unit is composed of high-brightness LED chips and diffused light guide materials. This size design enables the displayed characters to maintain clear legibility in long-distance viewing scenarios, meeting the special requirements for viewing distance in industrial environments.

[0064] Specifically, the large-size 7-segment LED display is connected to the main control board via an independent control circuit board, and its physical size is adapted to the modular layout of the instrument frame. In dynamic scanning drive mode, the bit selection signal is amplified by a transistor to control the cathode switching, enabling the large-size LED display to eliminate visual persistence even at low refresh rates. This design solves the signal delay problem caused by increased parasitic capacitance in large-size display units by optimizing the power output of the drive circuit, and works in conjunction with the power module of the main control board to ensure current stability after multi-stage voltage conversion.

[0065] This solution increases the physical size of the digital tube, thereby increasing the character display area by approximately 1.7 times. Simultaneously, combined with dynamic scanning drive technology, it avoids power consumption imbalances caused by the increased size while maintaining modular expandability. Furthermore, the pin spacing of the large-size digital tube is adapted to standardized connectors, simplifying the parallel installation process for multiple digital tubes.

[0066] Through the above technical solution, this application solves the problem of insufficient character recognition during long-distance observation in industrial scenarios, enabling the display instrument to provide readings without visual distortion even in large-space environments such as control rooms. The combination of large-size digital tubes and modular frames allows the display unit to flexibly increase or decrease the number of digits according to actual needs, while ensuring the integrity of the drive signal during long-distance transmission.

[0067] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, 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 this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0068] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A modular high-precision nixie display instrument, characterized in that: The meter frame, the main control panel and a plurality of digital tubes arranged on the meter frame, each of the digital tubes is provided with an independent digital tube control circuit board, and all the digital tube control circuit boards are connected with the main control panel.

2. A modular high-precision nixie display instrument according to claim 1, characterized in that: The main control panel comprises a power module, a main control module, an AD sampling module and a communication module, the power module is used for converting external input voltage into multiple stable output voltages for respectively supplying power to each functional module; the main control module is connected with the digital tube control circuit board, the AD sampling module and the communication module through a bus to realize data processing and control instruction issuing, the AD sampling module is used for collecting external analog signals and converting them into digital signals for processing by the main control module; and the communication module is used for data interaction with external equipment.

3. A modular high-precision nixie display instrument according to claim 2, characterized in that: The power module comprises multi-stage conversion circuits for converting 24V into 12V, 12V into 5V and 5V into 3.3V.

4. The modular high-precision nixie display instrument according to claim 1, characterized in that: The digital tube control circuit board is a digital tube driving module using a TM1637 chip.

5. The modular high-precision nixie display instrument according to claim 2, characterized in that: The AD sampling module comprises a front-end signal conditioning circuit, an ADC chip and a 2.5V reference voltage source; the front-end signal conditioning circuit uses an INA826AIDR precision amplifier, the ADC chip communicates with the main control module through an SPI interface, and the sampling data is output to the main control module after digital filtering.

6. A modular high-precision nixie display instrument according to claim 2, characterized in that: The communication module uses an RS485 half-duplex communication interface.

7. A modular high-precision nixie display instrument according to claim 2, characterized in that: The main control module uses an STM32F103C8T6 microcontroller.

8. The modular high-precision nixie display instrument according to claim 1, characterized in that: The digital tube is a large-size 7-segment digital tube.

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