NB-IoT (Narrow Band Internet of Things) data acquisition board, Internet of Things data acquisition device and data acquisition method

Abstract

The invention relates to the technical field of data acquisition devices, in particular to an NB-IoT (Narrow Band Internet of Things) data acquisition board, an Internet of Things data acquisition device and a data acquisition method.The NB-IoT data acquisition board comprises a power input control unit comprising a switching circuit, an NB-IoT communication unit, a UART (Universal Asynchronous Receiver / Transmitter) communication unit and an I2C (Inter-Integrated Circuit) communication unit, the UART communication unit provides a signal transmission and power supply channel for the far-end sensor, the I2C communication unit provides a signal transmission and power supply channel for the near-end sensor, and the power supply input control unit is connected to a power supply and supplies power to the NB-IoT communication unit and the UART communication unit. According to the invention, the sensor data is acquired in a time-sharing manner, after the NB-IoT communication unit acquires near-end sensor data through the I2C communication unit, the switching circuit is controlled to be turned on, the far-end sensor data is acquired through the UART communication unit, and after the far-end sensor data is acquired, the switching circuit is controlled to be turned off by the NB-IoT communication unit. The circuit structure is simpler, the cost is lower, more energy is saved, and the overall cost performance is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of data acquisition devices, and in particular to an NB-IoT data acquisition board, an Internet of Things data acquisition device and a data acquisition method. Background Art

[0002] With the rapid development of the Internet of Things industry, the continuous advancement of 5G low-power wide area network (LPWAN) NB-IoT technology and chip technology, many NB-IoT communication module products have been launched on the market. These communication modules are increasingly used in the field of Internet of Things data collection technology.

[0003] The existing Internet of Things data acquisition device based on NB-IoT technology is based on the microcontroller collecting sensor data, and realizes the wireless Internet access of the device by adding an NB-IoT communication module. This technical solution, firstly, does not fully utilize the hardware resources of the NB-IoT communication module, but simply uses it as a wireless transmission module. Secondly, it does not implement accurate dynamic management of energy consumption for the overall power supply system including the sensor, and there is a situation of "ineffective energy consumption", which invisibly requires a large-capacity battery for power supply. Therefore, the existing technical solution has not been able to give full play to the hardware and low power consumption advantages of the NB-IoT module in terms of technology, which will result in low cost performance of the product commercially, and will affect the popularization of NB-IoT technology in application, such as the existing technical solution of the utility model patent "Industrial and agricultural production environment data acquisition device based on NB-IoT technology" (authorization announcement number CN 211744735 U). This solution adopts the "MCU+NB-IoT communication module" technical architecture. The additional MCU data transfer link also increases the MCU cost and energy consumption. At the same time, the patent document does not show the dynamic management of energy consumption of the communication interface module and the sensor. In this way, even when the low-power main control chip and the NB-IoT communication module are in sleep state, the communication interface module and the sensor are still powered on, causing "ineffective energy consumption" in the system. Therefore, it is necessary to design a new type of Internet of Things data acquisition device to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that the hardware and low power consumption advantages of the NB-IoT module have not been fully utilized. An NB-IoT data acquisition board, an Internet of Things data acquisition device and a data acquisition method are proposed, which are optimized from two aspects of hardware architecture and energy-saving design. The circuit structure is simpler, the cost is lower, and the energy saving is higher, and the overall cost performance is greatly improved.

[0005] To achieve the above purpose, the technical solution adopted is: An NB-IoT data acquisition board comprises a power input control unit, an NB-IoT communication unit, and a UART communication unit and an I2C communication unit connected to the NB-IoT communication unit; The power input control unit is connected to the power supply to supply power to the connected NB-IoT communication unit and the UART communication unit respectively. The power input control unit includes a switch circuit, which is connected to the NB-IoT communication unit and is used to switch the power output to the UART communication unit; UART communication unit, used to provide signal transmission and power supply channels for remote sensors far away from the NB-IoT data acquisition board; An I2C communication unit is used to provide a signal transmission and power supply channel for a proximal sensor close to the NB-IoT data acquisition board, and the NB-IoT communication unit supplies power to the I2C communication unit; The NB-IoT communication unit, as the main control unit, collects the proximal sensor data through the I2C communication unit, controls the opening of the switch circuit, and collects the remote sensor data through the UART communication unit.

[0006] According to the NB-IoT data acquisition board of the present invention, further, the power input control unit also includes a connected protection circuit and a detection circuit; the protection circuit is used to implement overcurrent protection, voltage spike suppression and electromagnetic interference protection for the input power supply; the detection circuit is used to detect the power supply voltage V1 output by the protection circuit, and when the power supply voltage V1 is lower than a preset threshold, an undervoltage warning signal is output to the connected NB-IoT communication unit.

[0007] According to the NB-IoT data acquisition board of the present invention, further, the protection circuit includes a self-recovery fuse F1 connected in series at the power input end, a varistor RV1, a TVS tube D1 and a filter capacitor C1 connected in parallel in the power loop; The detection circuit is composed of a low-power voltage detection chip U1, which includes a VIN voltage input terminal and a signal output terminal. The VIN voltage input terminal is connected to the power supply voltage V1 output by the protection circuit, and the signal output terminal is connected to the NB-IoT communication unit. The switch circuit includes a load switch chip U2, which includes a VIN power input terminal, an ON / OFF control terminal and a VOUT power output terminal. The VIN power input terminal is connected to the supply voltage V1 output by the protection circuit, the ON / OFF control terminal is connected to the NB-IoT communication unit, and the VOUT power output terminal is connected to the UART communication unit.

[0008] According to the NB-IoT data acquisition board of the present invention, further, the NB-IoT communication unit includes a NB-IoT communication module and a NB-IoT power supply, a patch SIM card chip, a built-in antenna and a debugging serial port respectively connected to the NB-IoT communication module; The NB-IoT communication module is provided with an I / O input terminal, an I / O output terminal, a UART serial communication port, an I2C serial communication port and a VDD_EXT power supply output terminal, wherein the I / O input terminal is connected to the signal output terminal of the low-power voltage detection chip U1, and the I / O output terminal is connected to the ON / OFF control terminal of the load switch chip U2; The NB-IoT power supply is an LDO low-power linear regulator circuit 1, and the LDO low-power linear regulator circuit 1 is connected to the power supply voltage V1 output by the protection circuit.

[0009] According to the NB-IoT data acquisition board of the present invention, further, the UART communication unit includes an interface circuit 1 and an interface power supply 1 for providing a working voltage for the interface circuit 1, the interface circuit 1 is connected to the UART serial communication port of the NB-IoT communication module, and is used to provide a signal transmission channel for the remote sensor; the VOUT power supply output end of the load switch chip U2 is connected to the interface power supply 1, and is used to power the interface power supply 1, and the VOUT power supply output end of the load switch chip U2 is also used to power the remote sensor.

[0010] According to the NB-IoT data acquisition board of the present invention, further, the UART communication unit also includes a CN1 connection socket for connecting a remote sensor; The interface circuit 1 is a TTL to RS485 communication module U3, the TTL port of U3 is connected to the UART serial communication port, the A+ and B- ends of the RS485 port of U3 are correspondingly connected to the A+ and B- ends of the CN1 connector, and the power supply end and ground end of the CN1 connector are respectively connected to the VOUT power output end and GND of the load switch chip U2; the interface power supply 1 is an LDO low-power linear regulator circuit 2, which is used to provide a stable working voltage for the interface circuit 1, and the working voltage ensures that the levels between the interface circuit 1 and the UART serial communication port match each other.

[0011] According to the NB-IoT data acquisition board of the present invention, further, the I2C communication unit includes an interface circuit 2 and an interface power supply 2, the interface circuit 2 is connected to the I2C serial communication port of the NB-IoT communication module, and is used to provide a signal transmission channel for the proximal sensor; the interface power supply 2 is connected to the VDD_EXT power output terminal of the NB-IoT communication module, and is used to power the proximal sensor.

[0012] According to the NB-IoT data acquisition board of the present invention, further, the I2C communication unit also includes a CN2 connection socket for connecting a proximal sensor; The interface circuit 2 is composed of I2C_SDA and I2C_SCL data lines connected to the I2C serial communication port and pull-up resistors R61 and R62 respectively connected to the data lines; the other ends of the pull-up resistors R61 and R62 are both connected to the VDD_EXT power supply output terminal, and the I2C_SDA and I2C_SCL data lines are respectively connected to the SDA end and the SCL end of the CN2 connector; The interface power supply 2 is composed of a VDD_EXT power supply output terminal connected to a filter capacitor C61, an output terminal of the interface power supply 2 is connected to a power supply terminal of a CN2 connection socket, and a ground terminal of the CN2 connection socket is connected to GND.

[0013] According to the NB-IoT data acquisition board of the present invention, further, the power input control unit includes a connected protection circuit and a switch circuit, the NB-IoT power supply is composed of filter capacitors C51, C52, C53, and C54, and the power supply voltage V1 output by the protection circuit passes through the filter capacitors C51, C52, C53, and C54 and is connected to the VBAT power pin of the NB-IoT communication module; The NB-IoT communication module is internally integrated with an ADC unit for measuring the power supply voltage V1.

[0014] Furthermore, the present invention also provides an Internet of Things data acquisition device, including a shell, the shell including a base plate and a face shell connected to the base plate by snap-fitting, the top surface of the base plate is provided with an NB-IoT data acquisition board as described above; the upper surface of the face shell is provided with a cable waterproof connector, and the remote sensor cable passes through the cable waterproof connector and is electrically connected to the NB-IoT data acquisition board; the upper surface of the face shell is also provided with a sensor protective shell, and a proximal sensor electrically connected to the NB-IoT data acquisition board is provided in the sensor protective shell; a power hole is opened on the side of the face shell, and an external power cord passes through the power hole to connect to the NB-IoT data acquisition board.

[0015] Furthermore, the present invention also provides a data collection method for an Internet of Things data collection device, which is implemented based on the above-mentioned Internet of Things data collection device and comprises the following steps: Step 1: The NB-IoT communication unit is powered on or awakened from deep sleep, and the system is initialized; Step 2, the NB-IoT communication unit reads the undervoltage warning signal through the detection circuit or calculates the value of the power supply voltage V1 connected to the VBAT power pin of the NB-IoT communication module through the internal integrated ADC unit; Step 3, the NB-IoT communication unit reads the proximal sensor data through the I2C communication unit; Step 4: After the proximal sensor data is read, the NB-IoT communication unit controls the switch circuit to open; Step 5: The NB-IoT communication unit reads the remote sensor data through the UART communication unit; Step 6: After the remote sensor data is read, the NB-IoT communication unit controls the switch circuit to be closed; Step 7, the NB-IoT communication unit sends the undervoltage warning signal / the value of the power supply voltage V1, the proximal sensor data, and the distal sensor data to the IoT platform; Step 8, the NB-IoT communication unit checks whether there is a cache command issued by the IoT platform. If so, the NB-IoT communication unit parses the cache command and stores the parsed data. The cache command includes the deep sleep timer setting time of the NB-IoT communication unit. Step 9: The NB-IoT communication unit enters a timed deep sleep state and waits for the deep sleep timer to time out and wake up.

[0016] The beneficial effects achieved by adopting the above technical solution are: 1. Optimize the hardware architecture, reduce costs and save energy.

[0017] Different from the "MCU+NB-IoT communication module" architecture used in the prior art, the present invention saves the cost of the MCU part. The NB-IoT communication module is not only responsible for uploading data, but also undertakes the task of collecting sensor data. Since there is no data transfer link, the signal path is shorter. For the monitoring of the power supply voltage, the present invention adopts a low-power voltage detection chip or an internally integrated ADC unit. Compared with the external ADC power supply voltage detection circuit, the circuit structure of the present invention is simpler, the cost and energy consumption are lower, and the reliability of the entire system is also improved.

[0018] 2. Implement precise control of system energy consumption to reduce "ineffective energy consumption" during system sleep and system working hours.

[0019] The present invention optimizes the power supply design in a targeted manner according to the characteristics of different sensors and the actual energy consumption. For the I2C interface proximal sensor with short communication distance and low power consumption, the present invention selects the VDD_EXT power output of the internal output of the NB-IoT communication module as its power supply. For the RS485 interface remote sensor, due to the long communication distance and high power consumption, and the introduction of external interference signals, the circuit design adopts a power load switch chip with electrostatic discharge (ESD) protection, ultra-low static current (IQ) and shutdown current (ISD) as the power switch of the power input control unit, and dynamically controls the power supply of the UART communication unit. With the above design, when the system is in deep sleep state, the power supply of the I2C interface proximal sensor and the RS485 interface remote sensor is cut off, and the energy consumption of the entire system is reduced to a minimum. It has been measured that the sleep energy consumption of the entire system of the present invention is less than 4ua.

[0020] In terms of dynamic control of system energy consumption, the present invention adopts time-sharing collection of sensor data. After the NB-IoT communication unit is awakened, it first collects the voltage undervoltage warning signal / power supply voltage V1 value and the I2C interface proximal sensor data, and then turns on the switch circuit to collect the RS485 interface remote sensor data. After the data is read, the switch circuit is closed in time. This dynamic power control method, firstly, reduces the "invalid energy consumption" generated during the system working period, and secondly, during the reading of the I2C interface proximal sensor data, the switch circuit of the power input control unit is in the off state, which also avoids the introduction of external interference signals. At the same time, the Internet of Things platform can also adjust the time interval for collecting data by the NB-IoT data acquisition board by issuing cache commands, thereby making more reasonable use of limited battery energy.

[0021] In summary, through the above hardware optimization design and precise control of system energy consumption, the "ineffective energy consumption" during system sleep and system working hours is significantly reduced, and the external electromagnetic interference to the system is greatly reduced, thereby improving the overall electromagnetic compatibility of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings of the embodiments of the present invention, wherein the drawings are only used to illustrate some embodiments of the present invention, but not to limit all embodiments of the present invention thereto.

[0023] Figure 1 This is one of the structural block diagrams of the NB-IoT data acquisition board of an embodiment of the present invention; Figure 2 This is the second structural block diagram of the NB-IoT data acquisition board of an embodiment of the present invention; Figure 3 is a circuit diagram of a protection circuit according to an embodiment of the present invention; Figure 4 This is one of the circuit diagrams of the NB-IoT power supply according to an embodiment of the present invention; Figure 5 is a circuit diagram of a detection circuit according to an embodiment of the present invention; Figure 6 is a circuit diagram of a switch circuit according to an embodiment of the present invention; Figure 7 is a circuit diagram of a UART communication unit according to an embodiment of the present invention; Figure 8 is a circuit diagram of an I2C communication unit according to an embodiment of the present invention; Fig. 9 This is the third structural block diagram of the NB-IoT data acquisition board of an embodiment of the present invention; Fig.10 This is the second circuit diagram of the NB-IoT power supply according to an embodiment of the present invention; Fig.11 100 is a schematic diagram of the structure of the Internet of Things data acquisition device according to an embodiment of the present invention, in which 101 represents a base plate, 101 represents a surface shell, 102 represents a cable waterproof connector, 103 represents a sensor protective shell, 104 represents a proximal sensor, 105 represents a distal sensor cable, 106 represents an external power cord, and 107 represents an NB-IoT data acquisition board. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings of specific embodiments of the present invention to clearly and completely describe the exemplary scheme of the embodiment of the present invention. Unless otherwise defined, the technical terms or scientific terms used in the present invention should be the common meanings understood by people with ordinary skills in the field.

[0025] like Figure 1As shown, this embodiment discloses a NB-IoT data acquisition board, including a power input control unit 1, a NB-IoT communication unit 2, and a UART communication unit 3 and an I2C communication unit 4 connected to the NB-IoT communication unit 2. The power input control unit 1 is connected to the power supply to supply power to the connected NB-IoT communication unit 2 and the UART communication unit 3 respectively. The power input control unit 1 contains a switch circuit 13, which is connected to the NB-IoT communication unit 2. The NB-IoT communication unit 2 controls the on and off of the switch circuit 13 through high and low levels, thereby switching the power output to the UART communication unit 3. The UART communication unit 3 is used to provide a signal transmission and power supply channel for a remote sensor far away from the NB-IoT data acquisition board. The I2C communication unit 4 is used to provide a signal transmission and power supply channel for a proximal sensor close to the NB-IoT data acquisition board, and the NB-IoT communication unit 2 supplies power to the I2C communication unit 4. The NB-IoT communication unit 2, as the main control unit, collects proximal sensor data through the I2C communication unit 4, controls the opening of the switch circuit 13, and collects remote sensor data through the UART communication unit 3.

[0026] like Figure 2 As shown, the power input control unit 1 also includes a connected protection circuit 11 and a detection circuit 12. The protection circuit 11 is used to implement overcurrent protection, voltage spike suppression and electromagnetic interference protection for the input power supply. The detection circuit 12 is used to detect the power supply voltage V1 output by the protection circuit 11. When the power supply voltage V1 is lower than the preset threshold, an undervoltage warning signal is output to the connected NB-IoT communication unit 2. The power input end of the switch circuit 13 is connected to the power supply voltage V1.

[0027] like Figure 3 As shown, the protection circuit 11 includes a self-recovery fuse F1 connected in series at the power input end, and a varistor RV1, a TVS tube D1 and a filter capacitor C1 connected in parallel in the power loop.

[0028] Furthermore, the NB-IoT communication unit 2 includes a NB-IoT communication module 21 and a NB-IoT power supply 22, a patch SIM card chip, a built-in antenna and a debugging serial port for downloading debugging programs, which are respectively connected to the NB-IoT communication module 21. The NB-IoT communication module 21 is provided with an I / O input terminal, an I / O output terminal, a UART serial communication port, an I2C serial communication port and a VDD_EXT power supply output terminal. Among them, the I / O input terminal is set to an internal pull-up mode, the I / O output terminal is set to a push-pull output mode, and the VDD_EXT power supply is a 3.0V power supply output provided by the module to the outside. The NB-IoT power supply 22 is an LDO low-power linear regulator circuit 1, and the LDO low-power linear regulator circuit 1 is connected to the power supply voltage V1 output by the protection circuit 11.

[0029] Specifically, Figure 4 As shown, the LDO low-power linear regulator circuit 1 of this embodiment is composed of an LDO low-power linear regulator chip U5 and filter capacitors C51, C52, C53, and C54, and the LDO low-power linear regulator model is SSP7903. The NB-IoT power supply 22 not only ensures that the NB-IoT communication module 21 consumes microamperes of power in the deep sleep state, but also ensures that it can provide nearly 1A of current at the moment of waking up and connecting to the network.

[0030] like Figure 5 As shown, the detection circuit 12 is composed of a low-power voltage detection chip U1. Specifically, the model of the low-power voltage detection chip U1 is SSP61CN4202MR, and the preset threshold is 4.2V. It contains a VIN voltage input terminal and a signal output terminal. The VIN voltage input terminal is connected to the power supply voltage V1 output by the protection circuit 11, and the signal output terminal is connected to the I / O input terminal of the NB-IoT communication module 21; when the power supply voltage V1 is lower than the preset threshold value of 4.2V, the signal output terminal of the low-power voltage detection chip U1 outputs a low level, that is, outputs a low-level undervoltage warning signal to the I / O input terminal.

[0031] like Figure 6 As shown, the switch circuit 13 includes a load switch chip U2. Specifically, considering that the output end of the load switch chip U2 has better ESD compatibility with the external remote sensor, the load switch chip U2 adopts the power load switch chip TPS27081ADDCR with electrostatic discharge (ESD) protection and ultra-low static current (IQ) and shutdown current (ISD). The load switch chip U2 contains a VIN power input end, an ON / OFF control end and a VOUT power output end. The VIN power input end is connected to the power supply voltage V1 output by the protection circuit 11, the I / O output end of the NB-IoT communication module 21 is connected to the ON / OFF control end of the load switch chip U2, and the VOUT output end of the load switch chip U2 is connected to the UART communication unit 3, which is used to realize dynamic power supply for the UART communication unit 3 under the control of the NB-IoT communication module 21. In order to control the current surge impact on the subsequent circuits when the switch circuit is turned on, the opening slope time of the switch circuit 13 is controlled by adjusting the combination of R21, R22 and C21 in the switch circuit 13.

[0032] like Figure 7As shown, the UART communication unit 3 includes an interface circuit 131 and an interface power supply 132 for providing a working voltage for the interface circuit 131. The interface circuit 131 is connected to the UART serial communication port of the NB-IoT communication module to provide a signal transmission channel for the remote sensor. The VOUT power output terminal of the load switch chip U2 is connected to the interface power supply 1 to supply power to the interface power supply 132. The VOUT power output terminal of the load switch chip U2 is also used to supply power to the remote sensor.

[0033] The UART communication unit 3 also includes a CN1 connector for connecting a remote sensor. Specifically, the interface circuit 131 is a TTL to RS485 communication module U3. The TTL port of U3 is connected to the UART serial communication port. The A+ and B- terminals of the RS485 port of U3 are correspondingly connected to the 4 A+ terminals and 3 B- terminals of the CN1 connector. The VOUT power output terminal of the switch circuit 13 is connected to the 1 power terminal of the CN1 connector, and the 2 ground terminal of the CN1 connector is connected to GND. The interface power supply 132 is an LDO low-power linear regulator circuit 2. The interface power supply 132 is composed of an LDO low-power linear regulator U4 and filter capacitors C41 and C42. The LDO low-power linear regulator chip model is XC6206P332MR. The interface power supply 132 is used to provide a stable 3.3V operating voltage for the interface circuit 131. The operating voltage ensures that the levels between the interface circuit 131 and the UART serial communication port match each other.

[0034] like Figure 8 As shown, the I2C communication unit 4 includes an interface circuit 2 41 and an interface power supply 2 42. The interface circuit 2 41 is connected to the I2C serial communication port of the NB-IoT communication module 21 to provide a signal transmission channel for the proximal sensor; the interface power supply 2 42 is connected to the VDD_EXT power output terminal of the NB-IoT communication module 21 to power the proximal sensor.

[0035] The I2C communication unit 4 also includes a CN2 connector for connecting a proximal sensor. Specifically, the interface power supply 2 42 is composed of a VDD_EXT power supply output terminal connected to a filter capacitor C61, the VDD_EXT power supply is connected to the 3 power supply terminal of the CN2 connector via the filter capacitor C61, and the 4 ground terminal of the CN2 connector is connected to GND. The interface circuit 2 41 is composed of I2C_SDA and I2C_SCL data lines connected to the I2C serial communication port and pull-up resistors R61 and R62 respectively connected to the data lines, the other ends of the pull-up resistors R61 and R62 are both connected to the VDD_EXT power supply output terminal, and the I2C_SDA and I2C_SCL data lines are respectively connected to the 1SDA terminal and the 2SCL terminal of the CN2 connector.

[0036] like Fig. 9As shown, this embodiment also discloses another embodiment of the NB-IoT data acquisition board. When the NB-IoT data acquisition board is powered by a 3.3V-4.2V battery, the power input control unit 1 only includes a connected protection circuit 11 and a switch circuit 13, and the Figure 5 The detection circuit 12 shown. Fig.10 As shown, the NB-IoT power supply is composed of filter capacitors C51, C52, C53, and C54. The power supply voltage V1 output by the protection circuit 11 passes through the filter capacitors C51, C52, C53, and C54 and is connected to the NB-IoT communication module VBAT power supply pin. The NB-IoT communication module 21 is internally integrated with an ADC unit for measuring the power supply voltage V1. This voltage monitoring method makes it convenient for people to remotely monitor the real-time battery voltage value.

[0037] like Fig.11 As shown, this embodiment also discloses an IoT data acquisition device, including a housing, the housing including a bottom plate 100 and a face shell 101 snap-connected to the bottom plate 100, the top surface of the bottom plate 100 is provided with the NB-IoT data acquisition board 107 as described above, the upper surface of the face shell 101 is provided with a cable waterproof connector 102, and the remote sensor cable 105 passes through the cable waterproof connector 102 and is electrically connected to the NB-IoT data acquisition board 107. A sensor protection shell 103 is also provided on the upper surface of the face shell 101, and a proximal sensor 104 electrically connected to the NB-IoT data acquisition board 107 is provided in the sensor protection shell 103, and a power hole is also provided on the surface of the face shell 101, and an external power line 106 passes through the power hole to connect to the NB-IoT data acquisition board 107.

[0038] As an option, the sensor protection shell 103 includes but is not limited to a waterproof, dustproof and breathable temperature and humidity sensor protection shell and / or a light intensity sensor housing. The proximal sensor 104 includes but is not limited to an air temperature and humidity sensor and / or a light intensity sensor.

[0039] Based on the above-mentioned IoT data collection device, this embodiment further discloses a data collection method of the IoT data collection device, comprising the following steps: Step S1, the NB-IoT communication unit 2 is powered on or awakened from deep sleep, and the system is initialized. The system initialization includes initializing the port of the NB-IoT communication module 21 and reading the module deep sleep timer setting time in the module internal Flash memory.

[0040] Step S2, the NB-IoT communication unit 2 reads the undervoltage warning signal through the detection circuit 12 or calculates the value of the power supply voltage V1 connected to the VBAT power pin of the NB-IoT communication module through the internal integrated ADC unit.

[0041] Step S3, the NB-IoT communication unit 2 reads the proximal sensor data through the I2C communication unit 4. The NB-IoT communication unit 2 can read different proximal sensor data according to different I2C addresses.

[0042] Step S4: After the proximal sensor data is read, the NB-IoT communication unit 2 controls the switch circuit 13 to open.

[0043] Step S5, the NB-IoT communication unit 2 reads the remote sensor data through the UART communication unit 3. The NB-IoT communication unit 2 can read different remote sensor data according to different RS485 device addresses.

[0044] Step S6: After the remote sensor data is read, the NB-IoT communication unit 2 controls the switch circuit 13 to be closed.

[0045] Step S7, the NB-IoT communication unit 2 sends the undervoltage warning signal / the value of the supply voltage V1, the proximal sensor data and the distal sensor data to the Internet of Things platform.

[0046] Step S8, the NB-IoT communication unit 2 checks whether there is a cache command issued by the Internet of Things platform. If so, the NB-IoT communication unit 2 parses the cache command and stores the parsed data. The parsed data is stored in the internal Flash memory of the NB-IoT communication module 21. The cache command includes the deep sleep timer setting time of the NB-IoT communication unit 2.

[0047] Step S9, the NB-IoT communication unit 2 enters a timed deep sleep state, waiting for the deep sleep timer to time out and wake up.

[0048] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A NB-IoT data acquisition board, characterized in that: It includes a power input control unit, an NB-IoT communication unit, and a UART communication unit and an I2C communication unit connected to the NB-IoT communication unit; The power input control unit is connected to the power supply to supply power to the connected NB-IoT communication unit and the UART communication unit respectively. The power input control unit includes a switch circuit, which is connected to the NB-IoT communication unit and is used to switch the power output to the UART communication unit; UART communication unit, used to provide signal transmission and power supply channels for remote sensors far away from the NB-IoT data acquisition board; An I2C communication unit is used to provide a signal transmission and power supply channel for a proximal sensor close to the NB-IoT data acquisition board, and the NB-IoT communication unit supplies power to the I2C communication unit; The NB-IoT communication unit, as the main control unit, collects the proximal sensor data through the I2C communication unit, controls the opening of the switch circuit, and collects the remote sensor data through the UART communication unit.

2. The NB-IoT data acquisition board according to claim 1, characterized in that: The power input control unit also includes a connected protection circuit and a detection circuit; the protection circuit is used to implement overcurrent protection, voltage spike suppression and electromagnetic interference protection for the input power supply; the detection circuit is used to detect the power supply voltage V1 output by the protection circuit, and when the power supply voltage V1 is lower than a preset threshold, an undervoltage warning signal is output to the connected NB-IoT communication unit.

3. The NB-IoT data acquisition board according to claim 2, characterized in that: The protection circuit includes a self-recovery fuse F1 connected in series at the power input end, a varistor RV1, a TVS tube D1 and a filter capacitor C1 connected in parallel in the power loop; The detection circuit is composed of a low-power voltage detection chip U1, which includes a VIN voltage input terminal and a signal output terminal. The VIN voltage input terminal is connected to the power supply voltage V1 output by the protection circuit, and the signal output terminal is connected to the NB-IoT communication unit. The switch circuit includes a load switch chip U2, which includes a VIN power input terminal, an ON / OFF control terminal and a VOUT power output terminal. The VIN power input terminal is connected to the supply voltage V1 output by the protection circuit, the ON / OFF control terminal is connected to the NB-IoT communication unit, and the VOUT power output terminal is connected to the UART communication unit.

4. The NB-IoT data acquisition board according to claim 3, characterized in that: The NB-IoT communication unit includes a NB-IoT communication module and a NB-IoT power supply, a patch SIM card chip, a built-in antenna and a debugging serial port respectively connected to the NB-IoT communication module; The NB-IoT communication module is provided with an I / O input terminal, an I / O output terminal, a UART serial communication port, an I2C serial communication port and a VDD_EXT power supply output terminal, wherein the I / O input terminal is connected to the signal output terminal of the low-power voltage detection chip U1, and the I / O output terminal is connected to the ON / OFF control terminal of the load switch chip U2; The NB-IoT power supply is an LDO low-power linear regulator circuit 1, and the LDO low-power linear regulator circuit 1 is connected to the power supply voltage V1 output by the protection circuit.

5. The NB-IoT data acquisition board according to claim 4, characterized in that: The UART communication unit includes an interface circuit 1 and an interface power supply 1 for providing a working voltage for the interface circuit 1. The interface circuit 1 is connected to the UART serial communication port of the NB-IoT communication module and is used to provide a signal transmission channel for the remote sensor; the VOUT power output end of the load switch chip U2 is connected to the interface power supply 1 and is used to power the interface power supply 1. The VOUT power output end of the load switch chip U2 is also used to power the remote sensor.

6. The NB-IoT data acquisition board according to claim 5, characterized in that: The UART communication unit also includes a CN1 connector for connecting a remote sensor; The interface circuit 1 is a TTL to RS485 communication module U3, the TTL port of U3 is connected to the UART serial communication port, the A+ and B- ends of the RS485 port of U3 are correspondingly connected to the A+ and B- ends of the CN1 connector, and the power supply end and ground end of the CN1 connector are respectively connected to the VOUT power output end and GND of the load switch chip U2; the interface power supply 1 is an LDO low-power linear regulator circuit 2, which is used to provide a stable working voltage for the interface circuit 1, and the working voltage ensures that the levels between the interface circuit 1 and the UART serial communication port match each other.

7. The NB-IoT data acquisition board according to claim 4, characterized in that: The I2C communication unit includes an interface circuit 2 and an interface power supply 2. The interface circuit 2 is connected to the I2C serial communication port of the NB-IoT communication module to provide a signal transmission channel for the proximal sensor; the interface power supply 2 is connected to the VDD_EXT power output terminal of the NB-IoT communication module to power the proximal sensor.

8. The NB-IoT data acquisition board according to claim 7, characterized in that: The I2C communication unit also includes a CN2 connector for connecting to a proximal sensor; The interface circuit 2 is composed of I2C_SDA and I2C_SCL data lines connected to the I2C serial communication port and pull-up resistors R61 and R62 respectively connected to the data lines; the other ends of the pull-up resistors R61 and R62 are both connected to the VDD_EXT power supply output terminal, and the I2C_SDA and I2C_SCL data lines are respectively connected to the SDA end and the SCL end of the CN2 connector; The interface power supply 2 is composed of a VDD_EXT power supply output terminal connected to a filter capacitor C61, an output terminal of the interface power supply 2 is connected to a power supply terminal of a CN2 connection socket, and a ground terminal of the CN2 connection socket is connected to GND.

9. The NB-IoT data acquisition board according to claim 8, characterized in that: The power input control unit includes a connected protection circuit and a switch circuit. The NB-IoT power supply is composed of filter capacitors C51, C52, C53, and C54. The power supply voltage V1 output by the protection circuit passes through the filter capacitors C51, C52, C53, and C54 and is connected to the VBAT power pin of the NB-IoT communication module. The NB-IoT communication module is internally integrated with an ADC unit for measuring the power supply voltage V1.

10. An Internet of Things data collection device, characterized in that: The invention comprises a shell, which comprises a bottom plate and a surface shell connected with the bottom plate by snapping, and the top surface of the bottom plate is provided with the NB-IoT data acquisition board as described in any one of claims 1 to 9; the upper surface of the surface shell is provided with a cable waterproof connector, and the remote sensor cable is electrically connected to the NB-IoT data acquisition board through the cable waterproof connector; the upper surface of the surface shell is also provided with a sensor protection shell, and a proximal sensor electrically connected to the NB-IoT data acquisition board is provided in the sensor protection shell; a power hole is opened on the side of the surface shell, and an external power cord is connected to the NB-IoT data acquisition board through the power hole.

11. A data collection method for an Internet of Things data collection device, characterized in that: The method is implemented based on the Internet of Things data acquisition device according to claim 10, and comprises the following steps: Step 1: The NB-IoT communication unit is powered on or awakened from deep sleep, and the system is initialized; Step 2, the NB-IoT communication unit reads the undervoltage warning signal through the detection circuit or calculates the value of the power supply voltage V1 connected to the VBAT power pin of the NB-IoT communication module through the internal integrated ADC unit; Step 3, the NB-IoT communication unit reads the proximal sensor data through the I2C communication unit; Step 4: After the proximal sensor data is read, the NB-IoT communication unit controls the switch circuit to open; Step 5: The NB-IoT communication unit reads the remote sensor data through the UART communication unit; Step 6: After the remote sensor data is read, the NB-IoT communication unit controls the switch circuit to be closed; Step 7, the NB-IoT communication unit sends the undervoltage warning signal / the value of the power supply voltage V1, the proximal sensor data, and the distal sensor data to the IoT platform; Step 8, the NB-IoT communication unit checks whether there is a cache command issued by the IoT platform. If so, the NB-IoT communication unit parses the cache command and stores the parsed data. The cache command includes the deep sleep timer setting time of the NB-IoT communication unit. Step 9: The NB-IoT communication unit enters a timed deep sleep state and waits for the deep sleep timer to time out and wake up.

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