Passive electronic tag and detection device

Abstract

The utility model discloses a passive electronic tag and a detection device. The passive electronic tag comprises an antenna unit, an energy collection circuit unit, a radio frequency tag unit and a sensing unit, a radio frequency interface of the radio frequency tag unit is connected with the antenna unit, and a power output end of the radio frequency tag unit is connected with a power input end of the energy collection circuit unit. The power supply output end of the energy collection circuit unit is connected with the power supply end of the sensing unit and the power supply input end of the radio frequency tag unit, so that self-power supply is realized, the structure is simple, the cost is low, the load driving capacity is improved, and the detection sensitivity is improved.

Description

Technical Field

[0001] This utility model relates to the field of electronic tag technology, and in particular to a passive electronic tag and detection device. Background Technology

[0002] Currently, most solutions using Radio Frequency Identification (RFID) tags to monitor sensor parameters such as temperature, humidity, and air pressure employ active power methods. Static and dynamic power consumption ranges from a few milliwatts to tens of milliwatts, thus requiring external power. Power supply options include power supplies, batteries, and solar energy. However, due to wiring, battery requirements, or limitations related to ambient light, these solutions cannot achieve low cost, maintenance-free operation, adaptability, or suitability for dark environments. Utility Model Content

[0003] This invention provides a passive electronic tag and detection device that uses electromagnetic field energy in space to achieve self-powering. It has a simple structure, low cost, improved driving load capacity, and enhanced detection sensitivity.

[0004] In a first aspect, this utility model embodiment provides a passive electronic tag, including: an antenna unit, an energy harvesting circuit unit, an RFID tag unit, and a sensing unit;

[0005] The radio frequency interface of the RFID tag unit is connected to the antenna unit, the power output terminal of the RFID tag unit is connected to the power input terminal of the energy harvesting circuit unit, and the power output terminal of the energy harvesting circuit unit is connected to the power terminal of the sensing unit and the power input terminal of the RFID tag unit respectively.

[0006] Optionally, the passive electronic tag further includes a current limiting unit, which is disposed between the power input terminal of the RFID tag unit and the power output terminal of the energy harvesting circuit unit.

[0007] Optionally, the power input terminal and the power output terminal of the RFID tag unit are configured to the same power port. The passive electronic tag also includes an anti-backflow unit, which is provided between the power output terminal of the energy harvesting circuit unit and the power port.

[0008] Optionally, both the RFID tag unit and the sensing unit include a communication unit, and the RFID tag unit and the sensing unit form a master-slave communication connection through the communication unit.

[0009] Optionally, the communication unit includes at least one of an integrated circuit bus interface and a serial peripheral interface.

[0010] Optionally, the power output terminal of the energy harvesting circuit unit is also connected to the communication unit.

[0011] Optionally, the sensing unit includes at least one of a pressure sensing unit, a temperature and humidity sensing unit, a gas sensing unit, and an acceleration sensing unit.

[0012] Optionally, the energy harvesting circuit unit includes a first voltage conversion subunit, a second voltage conversion subunit, and an energy storage subunit, wherein the energy storage subunit is connected to the first voltage conversion subunit and the second voltage conversion subunit, respectively.

[0013] Secondly, embodiments of the present invention provide a detection device, including the passive electronic tag described in any embodiment of the present invention.

[0014] The technical solution provided by this utility model embodiment collects radio frequency energy through an RFID tag unit. The energy harvesting circuit unit then converts the collected RFID energy into a suitable operating voltage through storage and transformation processes, thereby driving the RFID tag unit and / or sensing unit. It can utilize electromagnetic field energy in space for self-powering, resulting in a simple structure and low cost. Simultaneously, it improves the driving load capacity and allows the RFID tag unit to operate in active mode, thereby enhancing detection sensitivity. Attached Figure Description

[0015] Figure 1 This invention provides a schematic diagram of the structure of a passive electronic tag according to an embodiment of the present invention;

[0016] Figure 2 This invention provides a schematic diagram of the structure of yet another passive electronic tag.

[0017] Figure 3 A schematic diagram of the structure of an energy harvesting circuit unit provided for the implementation of this utility model. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0019] With the widespread application of RFID tags in various environments, the limited application scenarios of passive tags hinder their further development. To overcome this obstacle, detection devices with sensors utilize external power supplies or self-contained batteries. However, implementing power-by-wire methods involves complex wiring, high costs, and certain electrical safety hazards. Meanwhile, self-contained batteries involve battery maintenance, leading to poor device reliability.

[0020] In some applications, RFID tags have their own power output function. However, these tags have low power consumption, usually less than 10uW. The power supply pins of RFID tags will not supply more than 2V@50Ua. Low-power sensors, on the other hand, typically have a peak power consumption close to 1mW. If the sensor is powered directly, the tag cannot support the sensor's power consumption to achieve sensing and detection.

[0021] In view of this, Figure 1 A schematic diagram of the structure of a passive electronic tag is provided for an embodiment of this utility model. See [link / reference]. Figure 1 It includes: antenna unit 110, energy harvesting circuit unit 120, radio frequency tag unit 130 and sensing unit 140;

[0022] The radio frequency interface of the RFID tag unit 130 is connected to the antenna unit 110. The power output terminal Vout2 of the RFID tag unit 130 is connected to the power input terminal Vin1 of the energy harvesting circuit unit 120. The power output terminal Vout1 of the energy harvesting circuit unit 120 is connected to the power supply terminal SUPPLY of the sensing unit 140 and the power input terminal Vin2 of the RFID tag unit 130, respectively.

[0023] Specifically, antenna unit 110 can convert radio frequency signals into a signal format suitable for recognition by RFID tag unit 130, and can also convert the signals of RFID tag unit 130 into radio frequency signals for transmission. RFID tag unit 130 receives and radiates electromagnetic wave signals through antenna unit 110 to achieve wireless reading and writing of information stored within the tag. For passive RFID tag unit 130, which lacks internal energy storage, it needs to obtain energy from the electromagnetic environment through antenna unit 110 to start the circuit. When antenna unit 110 receives electromagnetic wave signals, it converts the electromagnetic wave signals into alternating current through induction coil and resonant circuit to power the circuitry within RFID tag unit 130, achieving self-powering. For example, RFID tag unit 130 can use an RFID tag chip.

[0024] The energy from the RFID tag unit 130 can also be input to the energy harvesting circuit unit 120. The energy harvesting circuit unit 120 converts the RFID energy collected by the RFID tag unit 130 into a suitable operating voltage, such as a 1.2V-3.3V operating voltage range, through processes such as storage and voltage transformation, thereby driving the sensing unit 140. In some embodiments, the maximum driveable load output by the energy harvesting circuit unit 120 reaches 80mA@3.3V, which can improve the driving capability of the RFID tag chip by more than 1000 times the upper limit of load power consumption compared to 100uA@2V. Therefore, various low-power sensing units 140 can be integrated into the passive electronic tag, such as pressure sensing unit 140, temperature and humidity sensing unit 140, gas sensing unit 140, and acceleration sensing unit 140. The selection of sensors is no longer limited by power consumption and can support the operation of most general-purpose sensors. After the energy harvesting circuit unit 120 completes the charging process, the pins of the energy harvesting circuit unit 120 output a configurable voltage to power the radio frequency tag unit 130, thereby increasing the sensitivity of the radio frequency tag unit 130 in active mode by at least 15dB.

[0025] The technical solution provided by this utility model embodiment collects radio frequency energy through the RFID tag unit 130, and uses the energy harvesting circuit unit 120 to convert the radio frequency energy collected by the RFID tag unit 130 into a suitable operating voltage through processes such as storage and transformation, thereby driving the RFID tag unit 130 and / or the sensing unit 140. It can use the electromagnetic field energy in space to achieve self-powering, with a simple structure and low cost. At the same time, it improves the driving load capacity and can also enable the RFID tag unit 130 to operate in active mode, thereby improving the detection sensitivity.

[0026] See also Figure 1 Optionally, the passive electronic tag also includes a current limiting unit 150. The current limiting unit 150 is installed between the power input terminal Vin2 of the RFID tag unit 130 and the power output terminal Vout1 of the energy harvesting circuit unit 120. By setting the current limiting unit 150, excessive current entering the RFID tag unit 130 from the energy harvesting circuit unit 120 is prevented, thus protecting the RFID tag unit 130 from damage.

[0027] Figure 2 A schematic diagram of another passive electronic tag is provided for embodiments of this utility model. See [link to schematic diagram]. Figure 2 The power input terminal Vin2 and the power output terminal Vout2 of the RFID tag unit 130 are configured to the same power port VDD. The passive electronic tag also includes an anti-backflow unit 210. The anti-backflow unit 210 is provided between the power output terminal Vout1 of the energy harvesting circuit unit 120 and the power port VDD.

[0028] Specifically, the power port VDD of the RFID tag unit 130 can be directly connected to the power output terminal Vout1 of the energy harvesting circuit unit 120. Power is supplied to the internal logic circuits, digital circuits, or analog circuits of the chip through the power distribution network within the RFID tag unit 130, enabling the RFID tag unit 130 to operate in active mode. The energy harvested by the RFID tag unit 130 through the antenna unit 110 can be input to the power input terminal Vin1 of the energy harvesting circuit unit 120 through the power port VDD. Power output is achieved through the circuit design and internal power management logic within the RFID tag unit 130. At this time, the current limiting unit 150 between the power port VDD of the RFID tag unit 130 and the power output terminal Vout1 of the energy harvesting circuit unit 120 simultaneously limits the current supplied to both the power port VDD and the power input terminal Vin1 of the energy harvesting circuit unit 120. The power output terminal Vout1 of the energy harvesting circuit unit 120 is equipped with an anti-backflow unit 210 to prevent current from flowing back to the power output terminal Vout1 of the energy harvesting circuit unit 120 when the power port VDD of the RFID tag unit 130 is outputting power, thereby protecting the circuit and equipment from damage. For example, the anti-backflow unit 210 can employ a switching circuit to implement the anti-backflow function, such as a unidirectional diode and a MOSFET switch.

[0029] Optionally, both the RFID tag unit 130 and the sensing unit 140 include a communication unit 220, and the RFID tag unit 130 and the sensing unit 140 form a master-slave communication connection through the communication unit 220.

[0030] Specifically, the communication unit 220 of the RFID tag unit 130 and the sensing unit 140 has a universal digital communication interface, such as an Inter-Integrated Circuit (IIC) interface and a Serial Peripheral Interface (SPI) interface, providing a more convenient way for data interaction and saving external active logic chips, such as MCUs and FPGAs. Using the communication unit 220, the RFID tag unit 130 and the sensing unit 140 can form a master-slave communication connection. That is, interactive commands can be sent from the RFID tag unit 130 to the sensing unit 140 to realize control functions. This allows for convenient and efficient interface with various universal digital interfaces of the sensing unit 140. For example, in the above embodiment, the sensing unit 140 can be a BME280 sensor.

[0031] In application, external devices can directly operate the RFID tag unit 130 using its communication unit 220. Functionally, this is equivalent to a traditional passive electronic tag, enabling tag inventory and reading / writing to the tag memory. External devices can also obtain information from the RFID tag unit 130 via customized commands, and can access the sensing unit 140 through the communication unit 220 to read sensor measurements, facilitating the expansion of monitoring various physical quantities. For example, pressure, temperature, humidity, gas monitoring, and acceleration can be monitored. Communication with the sensing unit 140 allows the measured values ​​from the sensing unit 140 to be written to the external device's EEPROM or digital baseband internal register, which can then be read by a host computer. In other words, after receiving customized commands from an external device, the RFID tag unit 130 can access the sensing unit 140 through the communication unit 220, and the sensing unit 140 can transmit measured values ​​back through the communication unit 220. For example, the power supply for the communication unit 220 can also be obtained through the energy harvesting circuit unit 120, further reducing the complexity of the circuit.

[0032] Optional, Figure 3 A schematic diagram of an energy harvesting circuit unit provided for the implementation of this utility model is shown below. Figure 3 The energy harvesting circuit unit 120 includes a first voltage conversion subunit 121, a second voltage conversion subunit 122, and an energy storage subunit 123. The energy storage subunit 123 is connected to the first voltage conversion subunit 121 and the second voltage conversion subunit 122, respectively.

[0033] Specifically, the energy input from the RFID tag unit 130 is fed to the power input terminal Vin1 of the energy harvesting circuit unit 120. After being transformed by the first voltage conversion subunit 121, the energy is stored in the energy storage subunit 123. When there is a driving demand, the output voltage is adjusted by the second voltage conversion subunit 122 to adapt to the load requirements. The energy storage subunit 123 can be in the form of a rechargeable battery or an energy storage capacitor. The first voltage conversion subunit 121 can include one of a Boost, Charge, Pump, and Buck circuit, and the second voltage conversion subunit 122 can include one of an LDO and a Buck circuit. The transformation process of the first voltage conversion subunit 121 and the second voltage conversion subunit 122 is not limited to various combinations of rectification, boost, buck, voltage limiting, and voltage multiplication. For example, the energy harvesting circuit unit 120 can use energy harvesting chips such as AEM30940 or BQ25570.

[0034] This utility model embodiment also provides a detection device, which is set in the environment to be detected, and a data reading device. The data reading device establishes a communication connection with the passive electronic tag provided in any embodiment of this utility model. The data reading device can receive communication signals sent by the passive electronic tag, and can also send control commands to the passive electronic tag to realize functional control of the passive electronic tag. Since it includes the passive electronic tag provided in any embodiment of this utility model, it has the same beneficial effects, and will not be described again here.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A passive electronic tag, characterized in that, include: Antenna unit, energy harvesting circuit unit, RFID tag unit, and sensing unit; The radio frequency interface of the RFID tag unit is connected to the antenna unit, the power output terminal of the RFID tag unit is connected to the power input terminal of the energy harvesting circuit unit, and the power output terminal of the energy harvesting circuit unit is connected to the power terminal of the sensing unit and the power input terminal of the RFID tag unit respectively.

2. The passive electronic tag according to claim 1, characterized in that, It also includes a current limiting unit, which is provided between the power input terminal of the RFID tag unit and the power output terminal of the energy harvesting circuit unit.

3. The passive electronic tag according to claim 2, characterized in that, The power input terminal and the power output terminal of the RFID tag unit are configured to the same power port. The passive electronic tag also includes an anti-backflow unit, which is provided between the power output terminal of the energy harvesting circuit unit and the power port.

4. The passive electronic tag according to claim 1, characterized in that, Both the RFID tag unit and the sensing unit include a communication unit, and the RFID tag unit and the sensing unit form a master-slave communication connection through the communication unit.

5. The passive electronic tag according to claim 4, characterized in that, The communication unit includes at least one of an integrated circuit bus interface and a serial peripheral interface.

6. The passive electronic tag according to claim 5, characterized in that, The power output terminal of the energy harvesting circuit unit is also connected to the communication unit.

7. The passive electronic tag according to any one of claims 1-6, characterized in that, The sensing unit includes at least one of a pressure sensing unit, a temperature and humidity sensing unit, a gas sensing unit, and an acceleration sensing unit.

8. The passive electronic tag according to any one of claims 1-6, characterized in that, The energy harvesting circuit unit includes a first voltage conversion subunit, a second voltage conversion subunit, and an energy storage subunit, wherein the energy storage subunit is connected to the first voltage conversion subunit and the second voltage conversion subunit, respectively.

9. A detection device, characterized in that, Including the passive electronic tag as described in any one of claims 1-8.

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