TCR track circuit signal acquisition module

Abstract

The utility model relates to a TCR track circuit signal acquisition module, which comprises a power supply unit, an MCU unit, a PHY unit, a base plate unit and a PORT unit, the PORT unit comprises a DB9-M connector, the output end of the DB9-M connector is connected with an input isolation and impedance conversion circuit, the isolation and impedance conversion circuit is connected with an emitter follower circuit, and the emitter follower circuit is connected with a power supply unit. The emitter follower circuit is connected with an isolation amplifier, the output end of the isolation amplifier is connected with an AD module, and the AD module communicates with the MCU unit through an SPI serial port; a communication module is arranged between the MCU unit and the bottom plate unit, and the communication module comprises a CAN bus module and a 485 bus module; the base plate unit is connected with the power unit. According to the utility model, the isolation and impedance conversion circuit is arranged to filter high-frequency common-mode interference, the emitter follower circuit is arranged to enhance signal driving capability, reduce load effect and reduce signal attenuation, the isolation amplifier realizes electrical isolation of input and output ends, and the AD module is combined to realize signal acquisition.

Description

Technical Field

[0001] This utility model relates to the field of TCR track circuit signal acquisition and processing technology, specifically to a TCR track circuit signal acquisition module. Background Technology

[0002] The TCR (Track Circuit Reader) unit is an expansion board in the hardware platform system, primarily used to acquire TCR track circuit signals, forward them to the CPU board for analysis, and combine this with frequency information transmitted by the ATP (Automatic Train Protection) system to make judgments and issue warnings. The TCR unit includes a PORT unit, an MCU, and a baseboard unit. The PORT unit includes a DB9-M connector. The MCU acquires TCR track circuit signals through the DB9-M connector and then forwards them to the CPU board through the baseboard unit.

[0003] Due to environmental factors and electromagnetic interference, the original TCR track circuit signal is subject to noise and interference. This affects the amplitude, carrier frequency, low frequency, and spectral characteristics of the signal.

[0004] Therefore, there is an urgent need for a TCR signal acquisition module with better acquisition capabilities to improve the signal quality of the TCR track circuit and reduce noise and interference. Summary of the Invention

[0005] To address the problem of poor anti-interference and noise suppression performance of existing TCR units, this invention proposes a TCR track circuit signal acquisition module. It incorporates isolation and impedance transformation circuits to filter out high-frequency common-mode interference, an emitter follower circuit to enhance signal driving capability, reduce load effects, minimize signal attenuation, and an isolation amplifier to achieve electrical isolation between input and output terminals. This module, combined with an AD module, enables signal acquisition.

[0006] To achieve the above objectives, this utility model proposes a TCR track circuit signal acquisition module, including a power supply unit, an MCU unit, a PHY unit, and a baseboard unit, as well as a PORT unit. The PORT unit includes a DB9-M connector, the output of which is connected to an input isolation and impedance transformation circuit. The isolation and impedance transformation circuit is connected to an emitter follower circuit, which is connected to an isolation amplifier. The output of the isolation amplifier is connected to an AD module, and the AD module and the MCU unit communicate via an SPI serial port.

[0007] A communication module is provided between the MCU unit and the baseboard unit. The communication module includes a CAN bus module and a 485 bus module.

[0008] The base unit is connected to the power supply unit, which supplies power to the MCU unit, PORT unit, and PHY unit. The power supply unit includes a protection circuit, a MOS switching circuit, a DC12-3.3V conversion circuit, and a DC12-5V conversion circuit.

[0009] One side of the protection circuit is connected to the DC12V output of the base unit, and the other side is connected to the MOS switching circuit and then to the DC12-5V conversion circuit. The other side of the protection circuit is also connected to the DC12-3.3V conversion circuit.

[0010] Furthermore, the isolation and impedance transformation circuit includes a grounding resistor and a capacitor. The resistor is connected to the DB9-M connector, and one side is grounded, while the other side is connected to the capacitor. The capacitor is connected to the emitter follower circuit.

[0011] The isolation amplifier includes an AMC1350-Q1 chip.

[0012] Furthermore, the AD module includes an ADS131M02 chip.

[0013] The grounding resistance parameter is 500K to ensure that the input impedance meets the requirements, achieving strong driving capability in conjunction with the emitter follower, ensuring no signal distortion after isolation. The AMC1350-Q1 is an isolated precision amplifier with highly resistant electromagnetic interference (EMI) protection in both its output and input circuitry. The AMC1350-Q1's high-impedance input is optimized for connection to high-impedance resistive voltage dividers or other voltage signal sources with high output resistance. It features excellent accuracy and low temperature drift, supporting precise AC and DC voltage detection, with a nonlinearity of ±0.02% (maximum) to meet the requirements for raw waveform sampling and data acquisition accuracy.

[0014] The ADS131M02 chip features a 2-channel synchronous sampling differential input, a 24-bit Δ-Σ analog-to-digital converter, a programmable data rate up to 64kSPS, and an integrated low-drift internal voltage reference. It meets the requirements for raw waveform sampling and data acquisition accuracy.

[0015] Furthermore, the MCU unit is provided with peripheral circuitry, which includes a clock circuit, a decoupling circuit, a reset circuit, a current and voltage monitoring circuit, a slot position detection circuit, and an information storage circuit.

[0016] The pins of the MCU unit are also connected to the MII interface, RS485 interface and CAN interface. The MCU unit is connected to the PHY unit through the MII interface, the MCU unit is connected to the 485 bus module through the RS485 interface, and the MCU unit is connected to the CAN bus module through the CAN interface.

[0017] The output of the MCU unit is connected to the gate (G) of the MOS transistor in the MOS switching circuit;

[0018] The slot position detection circuit includes four GPIO pin output lines of the MCU unit, which are connected to the base plate unit.

[0019] The information storage circuit includes a memory, which communicates with the MCU unit via an I2C interface.

[0020] Furthermore, the protection circuit includes a resettable fuse and an LC filter circuit. The DC12V output of the base unit is connected to the resettable fuse and the LC filter circuit. The LC filter circuit is connected to the MOS switching circuit and the DC12-3.3V conversion circuit, respectively.

[0021] The DC12-3.3V conversion circuit includes the SY8120I chip;

[0022] The DC12-5V conversion circuit includes the IB1205XT-1WR3 isolated power supply chip.

[0023] After the DC12V output of the base unit is connected in series with a 0.5A self-resetting fuse and an LC filter circuit, it is connected to the current and voltage monitoring circuit. The voltage detection uses TI's INA138, which is a high-side single-machine current shunt monitor with a wide input range of 2.7-36V. It converts the differential input voltage into current output. At the same time, in order to reduce the impact of the downstream load on the monitoring circuit, the acquired signal is passed through a first stage emitter and then connected to the ADC pin of the MCU unit.

[0024] Furthermore, the PHY unit includes a DP83848I chip. The function of the PHY unit is to provide a 100Mbps network bus for the board, enabling communication between the board and other units in the system.

[0025] The beneficial effects of this utility model through the above technical solution are as follows:

[0026] This invention achieves precise acquisition of TCR track circuit signals. By setting up isolation and impedance transformation circuits, using grounding resistors to match the external impedance of the input, and combining capacitors to form a filter network, high-frequency common-mode interference can be effectively filtered out, improving signal purity. The introduction of the emitter follower circuit significantly enhances the signal driving capability, reduces the impact of load effects on the signal, and reduces signal attenuation during transmission, ensuring that the isolated signal can be transmitted without distortion, providing a stable and reliable input source for subsequent signal processing. An isolation amplifier is used to achieve reliable electrical isolation between the input and output terminals, ensuring the accuracy of original waveform sampling and data acquisition. An AD module is set up to meet the requirements of high-precision original waveform sampling and data acquisition. Combined with an MCU unit, it provides the hardware foundation for signal processing and transmission.

[0027] This invention relates to two utility models. The MCU unit integrates a CAN bus module and a 485 bus module between the MCU unit and the baseboard unit, supporting diverse communication protocols. This facilitates data interaction and system integration with external devices, improving module compatibility and scalability. Furthermore, the MCU unit, in conjunction with the PHY unit, provides the board with a 100Mbps network bus, enabling communication between the board and other units in the system. Attached Figure Description

[0028] Figure 1 This is one of the circuit schematic diagrams of a TCR track circuit signal acquisition module according to this utility model;

[0029] Figure 2 This is the second circuit schematic diagram of a TCR track circuit signal acquisition module according to this utility model.

[0030] Reference numerals: 1 for MCU unit, 2 for PORT unit, 3 for PHY unit, 4 for power supply unit, 5 for baseboard unit, 6 for DB9-M connector, 7 for emitter follower circuit, 8 for isolation amplifier, 10 for AD module, 11 for CAN bus module, 12 for 485 bus module, 13 for MOS switch circuit, 14 for DC12-3.3V conversion circuit, 15 for DC12-5V conversion circuit, 16 for slot position detection circuit. Detailed Implementation

[0031] Example 1

[0032] like Figures 1-2 As shown, a TCR track circuit signal acquisition module includes a power supply unit 4, an MCU unit 1, a PHY unit 3, and a baseboard unit 5, and also includes a PORT unit 2. The PORT unit 2 includes a DB9-M connector 6. The output terminal of the DB9-M connector 6 is connected to an input isolation and impedance transformation circuit. The isolation and impedance transformation circuit is connected to an emitter follower circuit 7. The emitter follower circuit 7 is connected to an isolation amplifier 8. The output terminal of the isolation amplifier 8 is connected to an AD module 10. The AD module and the MCU unit 1 communicate via an SPI serial port.

[0033] A communication module is provided between the MCU unit 1 and the base plate unit 5. The communication module includes a CAN bus module 11 and a 485 bus module 12.

[0034] The base plate unit 5 is connected to the power supply unit 4, which supplies power to the MCU unit 1, PORT unit 2, and PHY unit 3. The power supply unit 4 includes a protection circuit, a MOS switching circuit 13, a DC12-3.3V conversion circuit 14, and a DC12-5V conversion circuit 15.

[0035] One side of the protection circuit is connected to the DC12V output of the base unit 5, and the other side is connected to the MOS switch circuit 13 and then to the DC12-5V conversion circuit 15. The other side of the protection circuit is also connected to the DC12-3.3V conversion circuit 14.

[0036] The isolation and impedance transformation circuit includes a grounding resistor and a capacitor. The resistor is connected to DB9-M connector 6 and grounded on one side, and the capacitor is connected to the other side. The capacitor is connected to emitter follower circuit 7.

[0037] The isolation amplifier 8 includes an AMC1350-Q1 chip.

[0038] The grounding resistor has a 500K impedance, and MCU unit 1 uses an STM32F765 chip. The baseboard unit uses a Tyco 6469025.

[0039] The AD module 10 includes an ADS131M02 chip.

[0040] The MCU unit 1 is provided with peripheral circuits, which include a clock circuit, a decoupling circuit, a reset circuit, a current and voltage monitoring circuit, a slot position detection circuit 16, and an information storage circuit.

[0041] The pins of MCU unit 1 are also connected to MII interface, RS485 interface and CAN interface. MCU unit 1 is connected to PHY unit 3 through MII interface, MCU unit 1 is connected to 485 bus module 12 through RS485 interface, and MCU unit 1 is connected to CAN bus module 11 through CAN interface.

[0042] The output terminal of MCU unit 1 is connected to the gate (G) of the MOS transistor in MOS switching circuit 13;

[0043] The slot position detection circuit 16 includes four GPIO pin output lines of the MCU unit 1, which are connected to the base plate unit 5.

[0044] The information storage circuit includes a memory, which communicates with the MCU unit 1 via an I2C interface.

[0045] The protection circuit includes a resettable fuse and an LC filter circuit. The 5DC12V output of the base unit is connected to the resettable fuse and the LC filter circuit. The LC filter circuit is connected to the MOS switch circuit 13 and the DC12-3.3V conversion circuit 14, respectively.

[0046] The DC12-3.3V conversion circuit 14 includes the SY8120I chip;

[0047] The DC12-5V conversion circuit 15 includes the IB1205XT-1WR3 isolated power supply chip.

[0048] The PHY unit 3 includes a DP83848I chip.

[0049] During operation, the signal from the TCR track circuit is first received through the DB9-M connector 6 in PORT unit 2. The output of DB9-M connector 6 is connected to the input isolation and impedance transformation circuit, which consists of a grounding resistor (500K impedance) and a capacitor. The grounding resistor ensures that the input impedance meets the requirements, and the capacitor and resistor work together to filter out high-frequency common-mode interference, thus initially purifying the signal. The signal processed by the isolation and impedance transformation circuit enters the emitter follower circuit 7. The emitter follower circuit 7 enhances the signal's driving capability, reduces the load effect, and minimizes signal attenuation during subsequent transmission, ensuring that the signal is not distorted. The signal output from the emitter follower circuit 7 is connected to the isolation amplifier 8, and the analog signal output from the isolation amplifier 8 is connected to the AD module 10, which uses the ADS131M02 chip. The AD module 10 transmits the converted digital signal to the MCU unit 1 via SPI serial communication, which uses the STM32F765 chip. The MCU unit 1 further processes and analyzes the acquired data.

[0050] MCU unit 1 is equipped with various peripheral circuits, such as a clock circuit to provide a stable clock signal for the MCU, a decoupling circuit to ensure power supply stability, a reset circuit to reset the MCU when needed, a current and voltage monitoring circuit to monitor the current and voltage in the circuit, a slot position detection circuit 16 connected to the base unit 5 through four GPIO pin output lines to detect the slot position, and an information storage circuit that communicates with MCU unit 1 through an I2C interface to store relevant information.

[0051] MCU unit 1 is connected to PHY unit 3 via MII interface with pin connection. PHY unit uses DP83848I chip, which can realize communication with external network. It is connected to 485 bus module 12 via RS485 interface and CAN bus module 11 via CAN interface to communicate with baseboard unit 5 to realize data transmission and exchange.

[0052] The DC12V output of the base unit 5 is connected to the protection circuit of the power supply unit 4. The protection circuit consists of a self-resetting fuse and an LC filter circuit. The self-resetting fuse can automatically recover when the circuit experiences abnormal conditions such as overcurrent. The LC filter circuit further filters out interference signals in the power supply to ensure the stability of the power supply.

[0053] The DC12V power output from the protection circuit is connected in two ways: one to the DC12-3.3V conversion circuit 14 (using the SY8120I chip), which converts the voltage to 3.3V to power modules such as MCU unit 1 that require 3.3V power; the other is connected to the MOS switching circuit 13 and then to the DC12-5V conversion circuit 15 (using the IB1205XT-1WR3 isolated power chip), which converts the voltage to 5V to power modules such as PORT unit 2 and PHY unit 3 that require 5V power.

[0054] The output terminal of MCU unit 1 is connected to the gate of MOS transistor in MOS switching circuit 13, which can control the MOS switching circuit and thus control the power supply on and off.

[0055] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the patent claims of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. A TCR track circuit signal acquisition module, comprising a power supply unit (4), an MCU unit (1), a PHY unit (3) and a backplane unit (5), characterized in that, Also include PORT unit (2), the PORT unit (2) includes DB9-M connector (6), the DB9-M connector (6) output end is connected with input isolation, impedance conversion circuit, the isolation, impedance conversion circuit is connected with the shot randomizer circuit (7), the shot randomizer circuit (7) is connected with the isolated amplifier (8), the output end of the isolated amplifier (8) is connected AD module (10), the AD module and the MCU unit (1) are communicated through SPI serial interface; The communication module is arranged between the MCU unit (1) and the bottom plate unit (5), and the communication module comprises a CAN bus module (11) and a 485 bus module (12); The bottom plate unit (5) is connected with a power supply unit (4), the power supply unit (4) supplies power for the MCU unit (1), the PORT unit (2) and the PHY unit (3), and the power supply unit (4) comprises a protection circuit, a MOS switch circuit (13), a DC12-3.3V conversion circuit (14) and a DC12-5V conversion circuit (15); One side of the protection circuit is connected with the DC12V output of the bottom plate unit (5), the other side of the protection circuit is connected with the MOS switch circuit (13) and then connected with the DC12-5V conversion circuit (15), and the other side of the protection circuit is also connected with the DC12-3.3V conversion circuit (14).

2. The TCR track circuit signal acquisition module according to claim 1, characterized in that, The isolation, impedance conversion circuit comprises a grounding resistor and a capacitor, one side of the resistor is connected with the DB9-M connector (6) and grounded, and the other side of the resistor is connected with the capacitor, and the capacitor is connected with the shot randomizer circuit (7); The isolated amplifier (8) comprises an AMC1350-Q1 chip.

3. The TCR track circuit signal acquisition module according to claim 1, characterized in that, The AD module (10) comprises an ADS131M02 chip.

4. The TCR track circuit signal acquisition module according to claim 1, characterized in that, The MCU unit (1) is provided with a peripheral circuit, and the peripheral circuit comprises a clock circuit, a decoupling circuit, a reset circuit, a current voltage monitoring circuit, a plug slot position detection circuit (16) and an information storage circuit; The pin of the MCU unit (1) is also connected with an MII interface, an RS485 interface and a CAN interface, the MCU unit (1) is connected with the PHY unit (3) through the MII interface, the MCU unit (1) is connected with the 485 bus module (12) through the RS485 interface, and the MCU unit (1) is connected with the CAN bus module (11) through the CAN interface; The output end of the MCU unit (1) is connected with the MOS tube G pole of the MOS switch circuit (13); The plug slot position detection circuit (16) comprises four GPIO pin output lines of the MCU unit (1), and the four GPIO pin output lines of the MCU unit (1) are connected with the bottom plate unit (5); The information storage circuit comprises a memory, and the memory communicates with the MCU unit (1) through an I2C interface.

5. The TCR track circuit signal acquisition module according to claim 1, characterized in that, The protection circuit comprises a self-restoration fuse and an LC filter circuit, the DC12V output of the bottom plate unit (5) is connected with the self-restoration fuse and the LC filter circuit, and the LC filter circuit is connected with the MOS switch circuit (13) and the DC12-3.3V conversion circuit (14) respectively; The DC12-3.3V conversion circuit (14) comprises a SY8120I chip; The protection circuit comprises a self-restoration fuse and an LC filter circuit, the DC12V output of the bottom plate unit (5) is connected with the self-restoration fuse and the LC filter circuit, and the LC filter circuit is connected with the MOS switch circuit (13) and the DC12-3.3V conversion circuit (14) respectively; The DC 12-5V conversion circuit (15) comprises an IB1205XT-1WR3 isolation power supply chip.

6. The TCR track circuit signal acquisition module according to claim 1, characterized in that, The PHY unit (3) comprises a DP83848I chip.

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