NFC-based power supply method, power supply circuit, and passive electronic terminal having the power supply circuit

Abstract

A power supply method and power supply circuit based on NFC and a passive electronic terminal having the power supply circuit. The power supply method is used for an NFC device to supply power to a load through an antenna module, the antenna module has an NFC chip built in and has a coil, and includes: when the NFC device is close to the coil, an energy transmission channel is established, the coil generates a first energy to a first energy storage capacitor for first energy storage, and provides it to a micro control unit circuit to start it to start normal operation; when the NFC device detects an antenna feedback signal, a communication transmission channel is established, and an NFC carrier signal is transmitted to the antenna module, the coil generates a second energy to a second energy storage capacitor for second energy storage, wherein the second energy is greater than the first energy and the capacitance value of the second energy storage capacitor is greater than the capacitance value of the first energy storage capacitor, the micro control unit circuit receives the instruction and transmits it to the drive circuit, and the load is driven by the energy released by the second energy storage capacitor. The reverse power supply of the present invention has a fast response speed.

Description

Technical Field

[0001] The present invention relates to a power supply method and a power supply circuit, and particularly to a power supply method and a power supply circuit based on NFC, and a passive electronic terminal having the power supply circuit. Background Art

[0002] With the development of wireless technologies, products and applications based on NFC (Near Field Communication) technology have also developed rapidly, especially in payment and communication fields such as public transportation, access control, mobile payment, identity recognition, air parcel and luggage recognition, mail sorting, warehousing, and electronic anti-counterfeiting. However, in the field of wireless power supply and in the field of Internet of Things applications, applications that can simultaneously perform wireless near-field communication and reverse power supply (for example, using a mobile terminal such as a mobile phone as a mobile power supply to charge other devices is generally called reverse charging, and at this time, the mobile terminal such as a mobile phone can be called a "reverse power supply", while charging the mobile phone from a power source is generally called forward charging) are basically blank. The applications of the Internet of Things are becoming more and more extensive, and the convenient experience of mobile terminals is becoming more and more popular among the public. However, all the Internet of Things devices on the market currently use battery power supply or external power supply methods. Some devices that claim to be ultra-low power consumption or no power consumption still rely on external contact power supply or expensive dedicated wireless devices to wirelessly transmit weak power, and are far from the practical stage and cannot be popularized.

[0003] Currently, so-called passive electronic products on the market, such as electronic locks, have no battery inside and mainly rely on external contact-type contacts of dedicated devices for power supply and communication to work; another example is an NFC encryption card, which requires a dedicated card reader to work, and the output power is very small, only working at the microampere level. These products are mostly in the primary use stage or concept stage, and they mainly have two disadvantages. One is that the energy collected by the antenna is small and reliable and sustainable power supply cannot be truly achieved; the other is that in order to have strong load-carrying capacity, the external energy storage medium, the capacitor, is large. When detecting the two-way read-write handshake operation of NFC communication, due to the large energy absorption of the energy storage capacitor, the response of the receiving end becomes slow and the failure rate is high, affecting the user experience.

[0004] For example, in order to save power, existing NFC devices (such as mobile terminals) usually only perform timed detection. When they are close to the object being detected, they will sense whether there is an antenna feedback signal. In addition, the NFC carrier signal is generally intermittent and only turned on for a short time. Once the antenna is detected, the NFC device will fully turn on the NFC carrier signal to ensure communication. If the passive electronic device needs to absorb a lot of energy during close detection, the NFC carrier signal of the NFC device will be attenuated too much, and it will not be able to establish a two-way connection with the tag or it will be easily disconnected. The inability to connect will also cause the NFC carrier signal of the NFC device to not be fully turned on. Only when the voltage of the energy storage capacitor of the passive electronic device rises to a certain level can the NFC device detect the antenna communication, and then establish a connection with the antenna and control the circuit operation. However, this delay is relatively long, which seriously affects the user experience.

[0005] Therefore, how to provide a power supply method and a power supply circuit with fast response speed and capable of truly realizing reverse power supply to solve the problems faced by the prior art, such as the core problems of low efficiency, slow response, and mutual interference of energy storage media in various harsh environments, is indeed a topic that needs to be urgently solved in this field. Summary of the invention

[0006] In view of one or more defects of the above-mentioned prior art, an object of the present invention is to provide a power supply method and a power supply circuit based on NFC and a passive electronic terminal having the power supply circuit, which can truly realize reverse power supply with a fast response speed.

[0007] In order to achieve the above object, the present invention provides a power supply method based on NFC, which is characterized in that an NFC device is used to power a load through an antenna module, wherein the antenna module has a built-in NFC chip and a coil, and the power supply method includes:

[0008] When the NFC device is close to the coil of the antenna module, an energy transmission channel is established between the antenna module and the NFC device through the coil, and the coil generates a first energy to a first energy storage capacitor through magnetic field resonance for first energy storage, and provides the energy to a micro control unit circuit to start the micro control unit circuit to start normal operation;

[0009] When the NFC device detects an antenna feedback signal fed back by the antenna module, a communication transmission channel is established between the antenna module and the NFC device through the coil, and the NFC device transmits an NFC carrier signal to the antenna module through the communication transmission channel. The coil of the antenna module generates a second energy to a second energy storage capacitor for second energy storage by receiving the NFC carrier signal, where the second energy is greater than the first energy and the capacitance value of the second energy storage capacitor is greater than the capacitance value of the first energy storage capacitor, and the micro control unit circuit receives an instruction sent by the NFC chip and transmits it to a drive circuit, and the drive circuit receives the instruction and drives a load by the energy released by the second energy storage capacitor.

[0010] In an embodiment of the present invention, the NFC-based power supply method further includes: converting the generated first energy and second energy into regulated DC electrical energy through a rectifying circuit and transmitting it to the first energy storage capacitor and the second energy storage capacitor.

[0011] In an embodiment of the present invention, the NFC-based power supply method further includes:

[0012] During the first energy storage, the micro control unit circuit closes the switch to make the second energy storage capacitor in a charging-off state that does not absorb energy;

[0013] During the second energy storage, the micro control unit circuit opens the switch to make the second energy storage capacitor in a charging-on state that absorbs energy.

[0014] In an embodiment of the present invention, the micro control unit circuit controls the switch to open to make the second energy storage capacitor in a charging-on state that absorbs energy for second energy storage when detecting that the output voltage of the coil rises; and / or, the micro control unit circuit starts to respond to receive the instruction from the NFC chip when the second energy storage capacitor reaches a matching state sufficient to drive the load during the second energy storage.

[0015] To achieve the above object, the present invention further provides an NFC-based power supply circuit, which is characterized in that it includes:

[0016] An antenna module, which is built-in with an NFC chip and has a coil and a voltage output node;

[0017] A first energy storage module, which is connected to the coil through the voltage output node and has a first energy storage capacitor;

[0018] A second energy storage module, which is connected to the coil through the voltage output node and has a second energy storage capacitor and a switch for controlling the charging-on / off of the second energy storage capacitor, and the capacitance value of the second energy storage capacitor is greater than the capacitance value of the first energy storage capacitor;

[0019] A micro - control unit circuit is connected to the coil, the first energy storage module, and the second energy storage module through the voltage output node;

[0020] A drive circuit is connected to the micro - control unit circuit and is connected to the second energy storage capacitor through the voltage output node;

[0021] Wherein, when the NFC device approaches the coil of the antenna module, an energy transfer channel between the antenna module and the NFC device is established through the coil, and the coil generates a first energy through magnetic field resonance to the first energy storage capacitor for first - stage energy storage, and supplies it to the micro - control unit circuit to start the micro - control unit circuit to start normal operation;

[0022] When the NFC device detects an antenna feedback signal fed back by the antenna module, a communication transmission channel between the antenna module and the NFC device is established through the coil, and the NFC device transmits an NFC carrier signal to the antenna module through the communication transmission channel. The coil of the antenna module generates a second energy through receiving the NFC carrier signal to the second energy storage capacitor for second - stage energy storage, wherein the second energy is greater than the first energy, and the micro - control unit circuit receives an instruction sent by the NFC chip and transmits it to a drive circuit, and the drive circuit receives the instruction and drives a load through the energy released by the second energy storage capacitor.

[0023] In another embodiment of the present invention, the NFC - based power supply circuit further includes: a rectifier circuit, which has two input nodes and two output nodes. The two input nodes are respectively connected to both ends of the coil, one of the two output nodes is connected to the voltage output node, and the other of the two output nodes is grounded. Wherein the generated first energy and second energy are converted into regulated DC electrical energy through the rectifier circuit and transmitted to the first energy storage capacitor and the second energy storage capacitor.

[0024] In another embodiment of the present invention, the rectifier circuit is a full - bridge rectifier circuit composed of four first diodes; and / or, the positive terminal of the first energy storage capacitor is connected to the voltage output node, and the negative terminal of the first energy storage capacitor is connected to the other of the two output nodes of the rectifier circuit and is grounded simultaneously.

[0025] In another embodiment of the present invention, the switch of the second energy storage module includes a first transistor switch and a second transistor switch, and the second energy storage module further includes a second diode. Wherein,

[0026] The first transistor switch, its first end is connected to the micro - control unit circuit, its second end is connected to the first end of the second transistor switch, and its third end is grounded;

[0027] The second transistor switch has its second terminal connected to the voltage output node and its third terminal connected to the positive terminal of the second energy storage capacitor;

[0028] The negative terminal of the second energy storage capacitor is connected to the third terminal of the first transistor and is grounded simultaneously;

[0029] The positive terminal of the second diode is connected to the positive terminal of the second energy storage capacitor, and the negative terminal of the second diode is connected to the voltage output node and is connected to the micro - control unit circuit and the drive circuit;

[0030] Wherein, during the first energy storage, the micro - control unit circuit makes the second energy storage capacitor in a charging - off state of not absorbing energy by turning off the first transistor switch and the second transistor switch;

[0031] During the second energy storage, the micro - control unit circuit makes the second energy storage capacitor in a charging - on state of absorbing energy by turning on the first transistor switch and the second transistor switch.

[0032] In another embodiment of the present invention, the micro - control unit circuit controls the switch to turn on when the output voltage of the coil is detected to rise at the voltage output node, so that the second energy storage capacitor is in a charging - on state of absorbing energy for the second energy storage; and / or, the micro - control unit circuit starts to respond to receive the instruction from the NFC chip when the second energy storage capacitor reaches a matching state sufficient to drive the load during the second energy storage.

[0033] To achieve the above - mentioned purpose, the present invention further provides a passive electronic terminal, which is characterized in that it has the power supply circuit as described above.

[0034] By dividing the energy storage medium (such as a capacitor) in the circuit into a primary power supply system (i.e., the first energy storage capacitor is used for the first energy storage and power supply) and a secondary power supply system (i.e., the second energy storage capacitor is used for the second energy storage and power supply), the present invention can directly absorb the reverse energy of NFC devices (such as mobile terminals, mobile phones), upgrade the Internet of Things products from a battery - equipped design to a battery - free practical level, lay a technical foundation for the wide application of passive Internet of Things products, and achieve rapid civilian popularity.

[0035] The advantages of the present invention are as follows: no external power supply, zero power consumption, fast reverse - power - supply response, high output power, simple circuit, low cost, solving the application blank of NFC wireless power supply in meeting multi - task processing of communication, power supply and encryption in Internet of Things products, truly having the value of mass commercial use in multiple fields, and reducing the future dependence of traditional electronic products on disposable batteries and the pollution brought by batteries to the environment. Description of the Drawings

[0036] To make the above and other objects, features, and advantages of the present invention more apparent and understandable, the description of the accompanying drawings is as follows:

[0037] Figure 1 It is a schematic diagram of a preferred NFC-based power supply method of the present invention;

[0038] Figure 2 It is a schematic structural diagram of a preferred NFC-based power supply circuit of the present invention. Detailed implementation manners

[0039] To make the description of the present invention more detailed and complete, reference may be made to the accompanying drawings and the following various embodiments. The same numbers in the drawings represent the same or similar components. On the other hand, well-known components and steps are not described in the embodiments to avoid unnecessary limitations to the present invention. In addition, for the purpose of simplifying the drawings, some well-known conventional structures and elements will be shown in a simple schematic manner in the drawings.

[0040] As Figure 1 shown, the present invention provides an NFC-based power supply method, which can be used for an NFC device to supply power to a load through an antenna module. The antenna module is built with an NFC chip and has a coil. Wherein, the power supply method includes:

[0041] Step 12, when the NFC device approaches the coil of the antenna module, an energy transmission channel between the antenna module and the NFC device is established through the coil, and the coil generates a first energy through magnetic field resonance to a first energy storage capacitor for first energy storage, and provides it to a micro-control unit circuit to start the micro-control unit circuit to start normal operation;

[0042] Step 14, when the NFC device detects an antenna feedback signal fed back by the antenna module, a communication transmission channel between the antenna module and the NFC device is established through the coil, and the NFC device transmits an NFC carrier signal to the antenna module through the communication transmission channel. The coil of the antenna module generates a second energy to a second energy storage capacitor for second energy storage through receiving the NFC carrier signal. The second energy is greater than the first energy and the capacitance value of the second energy storage capacitor is greater than that of the first energy storage capacitor, and the micro-control unit circuit receives the instruction sent by the NFC chip and transmits it to a driving circuit. The driving circuit receives the instruction and drives a load through the energy released by the second energy storage capacitor.

[0043] Preferably, in the present invention, the NFC-based power supply method may further include: converting the generated first energy and second energy into regulated DC electrical energy through a rectifying circuit and transmitting it to the first energy storage capacitor and the second energy storage capacitor.

[0044] Moreover, the NFC-based power supply method may further include: during the first energy storage, the microcontroller unit circuit makes the second energy storage capacitor in a charging-off state where it does not absorb energy by turning off the switch; during the second energy storage, the microcontroller unit circuit makes the second energy storage capacitor in a charging-on state where it absorbs energy by turning on the switch.

[0045] In the present invention, for example, when the microcontroller unit circuit detects that the output voltage of the coil increases, it controls the switch to turn on to make the second energy storage capacitor in a charging-on state where it absorbs energy for the second energy storage. For example, when the second energy storage capacitor reaches a matching state sufficient to drive the load during the second energy storage, the microcontroller unit circuit starts to respond to receive instructions from the NFC chip.

[0046] Correspondingly, as Figure 2 shown, the present invention further provides an NFC-based power supply circuit, which includes an antenna module 21, a first energy storage module 22, a second energy storage module 23, a microcontroller unit circuit (i.e., MCU circuit) 24, and a drive circuit 25. More preferably, the power supply circuit may further include a rectifier circuit 26.

[0047] The antenna module 21 is built-in with an NFC chip and has a coil L1 and a voltage output node VCC.

[0048] The rectifier circuit 26 is, for example, a full-bridge rectifier circuit composed of four first diodes D1, which has two input nodes (such as node 1 and node 3) and two output nodes (such as node 2 and node 4). Among them, the two input nodes, such as node 1 and node 3, are respectively connected to both ends of the coil L1, one of the two output nodes (such as node 2) is connected to the voltage output node VCC, and the other of the two output nodes (such as node 4) is grounded.

[0049] The first energy storage module 22 is connected to the coil L1 through the voltage output node VCC and has a first energy storage capacitor C1. For example, the positive terminal of the first energy storage capacitor C1 can be connected to the voltage output node VCC, and the negative terminal of the first energy storage capacitor C1 can be connected to the other of the two output nodes of the rectifier circuit 26 (such as node 4) and grounded at the same time.

[0050] The second energy storage module 23 is connected to the coil L1 through the voltage output node VCC and has a second energy storage capacitor C2 and a switch for controlling the charging on / off of the second energy storage capacitor C2, and the capacitance value of the second energy storage capacitor C2 is greater than that of the first energy storage capacitor C1. Preferably, the switch may include, for example, a first transistor switch Q1 and a second transistor switch Q2, and the second energy storage module 23 further includes a second diode D2. Among them, the first end of the first transistor switch Q1 is connected to the micro-control unit circuit 24, the second end of the first transistor switch Q1 is connected to the first end of the second transistor switch Q2, and the third end of the first transistor switch Q1 is grounded. The second end of the second transistor switch Q2 is connected to the voltage output node VCC, and the third end of the second transistor switch Q2 is connected to the positive end of the second energy storage capacitor C2. The negative end of the second energy storage capacitor C2 is connected to the third end of the first transistor Q1 and is grounded simultaneously. The positive end of the second diode D2 is connected to the positive end of the second energy storage capacitor C2, and the negative end of the second diode D2 is connected to the voltage output node VCC and is connected to the micro-control unit circuit 24 and the drive circuit 25. Preferably, a first resistor R1 is further connected between the first end of the first transistor switch Q1 and the micro-control unit circuit 24; a second resistor R2 is further connected between the first end and the third end of the first transistor switch Q1 and is grounded simultaneously; a third resistor R3 is further connected between the second end of the first transistor switch Q1 and the first end of the second transistor switch Q2.

[0051] The micro-control unit circuit 24 is connected to the coil L1, the first energy storage module 22, and the second energy storage module 23 through the voltage output node VCC.

[0052] The drive circuit is connected to the micro-control unit circuit 24 and is connected to the second energy storage capacitor C2 through the voltage output node VCC.

[0053] Among them, when an NFC device (not shown in the figure) approaches the coil L1 of the antenna module 21, an energy transmission channel can be established between the antenna module 21 and the NFC device through the coil L1, and the coil L1 can generate a first energy to the first energy storage capacitor through magnetic field resonance for first energy storage, and can provide energy to the micro-control unit circuit 24 to start the micro-control unit circuit 24 to start normal operation.

[0054] When the NFC device detects an antenna feedback signal fed back by the antenna module 21, a communication transmission channel can be established between the antenna module 21 and the NFC device through the coil L1, and the NFC device can transmit an NFC carrier signal to the antenna module 21 through this communication transmission channel. The coil L1 of the antenna module 21 can generate a second energy to the second energy storage capacitor C2 to perform second energy storage by receiving the NFC carrier signal, wherein the second energy is greater than the first energy. Moreover, the micro-control unit circuit 24 can receive an instruction sent by the NFC chip of the antenna module 21 and transmit it to a driving circuit 25, and the driving circuit 25 can receive the instruction and drive a load by the energy released by the second energy storage capacitor C2.

[0055] In the present invention, preferably, the first energy and the second energy generated by the coil L1 can be converted into regulated DC electrical energy through the rectification circuit 26 and transmitted to the first energy storage capacitor C1 and the second energy storage capacitor C2. Moreover, when performing the first energy storage, the micro-control unit circuit 24 can make the second energy storage capacitor C2 in a charging-off state that does not absorb energy by turning off the first transistor switch Q1 and the second transistor switch Q2. When performing the second energy storage, the micro-control unit circuit 24 can make the second energy storage capacitor C2 in a charging-on state that absorbs energy by turning on the first transistor switch Q1 and the second transistor switch Q2.

[0056] More preferably, the micro-control unit circuit 24 controls the switches (such as Q1 and Q2) to turn on when the output voltage of the coil L1 is detected to increase at the voltage output node VCC, so that the second energy storage capacitor C2 is in a charging-on state that absorbs energy to perform the second energy storage. Moreover, the micro-control unit circuit 24 starts to respond to receive an instruction from the NFC chip when the second energy storage capacitor C2 reaches a matching state sufficient to drive the load during the second energy storage.

[0057] In the present invention, a passive electronic terminal is further provided, which can have the power supply circuit as described above.

[0058] More specifically, in combination with the power supply circuit as shown in Figure 2 The power supply method of the present invention may include the following steps:

[0059] (1) When an NFC device (such as a mobile terminal, a mobile phone with NFC function) approaches the coil L1 of the antenna module 21, on the premise that the magnetic fields on both sides are induced, an energy transmission channel can be established between the antenna module 21 and the NFC device, and the first energy (smaller energy) generated by magnetic field resonance can be provided to the first energy storage capacitor C1 with a smaller capacitance value through the coil L1 for rapid charging (i.e., performing the first energy storage).

[0060] (2) At this time, the voltage of the voltage output node VCC in the second energy storage module 23 is relatively low, and the first energy can be provided to start the MCU circuit 24, enabling it to start normal operation to control the switches Q1 and Q2 in the second energy storage module 23 not to turn on. At this time, the second energy storage capacitor C2 in the second energy storage module 23 does not absorb energy.

[0061] (3) When the NFC device detects the antenna feedback signal of the antenna module 21 (such as detecting a tag), a communication transmission channel can be established between the antenna module 21 and the NFC device, and two-way communication can start. At this time, the NFC carrier signal of the NFC device can be fully turned on, and energy is transmitted through this energy transmission channel. The coil L1 of the antenna module 21 receives the NFC carrier signal and generates a second energy. At this time, the voltage of the voltage output node VCC increases. When the MCU circuit 24 detects the increase in voltage, it starts to control the switches Q1 and Q2 in the second energy storage module 23 to turn on.

[0062] (4) After the switches Q1 and Q2 in the second energy storage module 23 are turned on, the generated second energy can start to quickly charge the second energy storage capacitor C2 with a relatively large capacitance value (i.e., perform second energy storage), and after effective time and power matching, it reaches a matching state sufficient to drive the load to work.

[0063] (5) At this time, the MCU circuit 24 starts to respond to and receive instructions from the internal communication interface of the built-in NFC chip, and conveys the instructions to the drive circuit 25.

[0064] (6) When the drive circuit 25 receives the instructions from the MCU circuit 24, at the same time, the large energy supplied by releasing the electric energy stored in the second energy storage capacitor C2 through the second diode D2 can be used to drive the load to work.

[0065] In the present invention, by dividing the energy storage medium in the circuit (such as a capacitor) into a primary power supply system (i.e., performing primary energy storage and power supply through the first energy storage capacitor) and a secondary power supply system (i.e., performing secondary energy storage and power supply through the second energy storage capacitor), it can directly absorb the reverse energy of the NFC device (such as a mobile terminal, a mobile phone), improve the Internet of Things product from a battery-powered design to a battery-free practical level, lay a technical foundation for the wide application of passive Internet of Things products, and achieve rapid civilian popularity.

[0066] Moreover, by adopting a time-division multiplexing working mechanism, when the NFC device (such as a mobile terminal) detects the antenna, it initially absorbs only a small amount of energy to quickly establish a connection with the antenna. After detecting the antenna, the NFC carrier signal of the NFC device is fully turned on, and at this time, the control circuit absorbs a large amount of energy through the second energy storage capacitor to supply the control circuit and the driving circuit, thereby accelerating the response speed of the antenna, enhancing the user experience, and achieving the effect of popularization and practical use.

[0067] The advantages of the present invention are as follows: no external power supply, zero power consumption, fast reverse power supply response, high output power, simple circuit, low cost, solving the application blank of NFC wireless power supply in meeting multi-task processing of communication, power supply and encryption in Internet of Things products, truly having the value of mass commercial use in multiple fields, and reducing the future dependence of traditional electronic products on disposable batteries and the pollution brought by batteries to the environment.

[0068] Although the present invention has been disclosed above in the form of embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the appended claims.

Claims

1. A power supply method based on NFC, characterized in that, it is used for an NFC device to supply power to a load through an antenna module, wherein the antenna module is built-in with an NFC chip and has a coil and a voltage output node, and the power supply method includes: When the NFC device approaches the coil of the antenna module, an energy transmission channel is established between the antenna module and the NFC device through the coil, and the coil generates a first energy through magnetic field resonance to a first energy storage capacitor for first energy storage, and supplies it to a micro-control unit circuit to start the normal operation of the micro-control unit circuit; When the NFC device detects an antenna feedback signal fed back by the antenna module, a communication transmission channel is established between the antenna module and the NFC device through the coil, and the NFC device transmits an NFC carrier signal to the antenna module through the communication transmission channel. The coil of the antenna module generates a second energy through receiving the NFC carrier signal to a second energy storage capacitor of a second energy storage module for second energy storage, wherein the second energy is greater than the first energy and the capacitance value of the second energy storage capacitor is greater than the capacitance value of the first energy storage capacitor, and the micro-control unit circuit receives the instruction sent by the NFC chip and transmits it to a drive circuit, and the drive circuit receives the instruction and drives a load through the energy released by the second energy storage capacitor; Wherein, the switch for controlling the charging on / off of the second energy storage capacitor includes a first transistor switch and a second transistor switch, and the second energy storage module further includes a second diode, wherein, The first transistor switch, its first end is connected to the micro-control unit circuit, its second end is connected to the first end of the second transistor switch, and its third end is grounded; The second transistor switch, its second end is connected to the voltage output node, and its third end is connected to the positive end of the second energy storage capacitor; The negative end of the second energy storage capacitor is connected to the third end of the first transistor and grounded at the same time; The positive end of the second diode is connected to the positive end of the second energy storage capacitor, and the negative end of the second diode is connected to the voltage output node and connected to the micro-control unit circuit and the drive circuit; Wherein, during the first energy storage, the micro-control unit circuit makes the second energy storage capacitor in a charging off state that does not absorb energy by turning off the first transistor switch and the second transistor switch; During the second energy storage, the micro-control unit circuit makes the second energy storage capacitor in a charging on state that absorbs energy by turning on the first transistor switch and the second transistor switch.

2. The NFC-based power supply method according to claim 1, characterized in that, further includes: Converting the generated first energy and second energy into regulated DC electrical energy through a rectifier circuit and transmitting it to the first energy storage capacitor and the second energy storage capacitor.

3. The NFC-based power supply method according to claim 2, characterized in that, The micro-control unit circuit controls the switch to turn on when detecting that the output voltage of the coil rises, so that the second energy storage capacitor is in a charging on state that absorbs energy to perform second energy storage; and / or, The microcontroller unit circuit starts to respond to and receive the instruction from the NFC chip when the second energy storage capacitor is charged for the second time to a matching state sufficient to drive the load.

4. An NFC-based power supply circuit characterized in that it includes: An antenna module, which is built-in with an NFC chip and has a coil and a voltage output node; A first energy storage module, which is connected to the coil through the voltage output node and has a first energy storage capacitor; A second energy storage module, which is connected to the coil through the voltage output node and has a second energy storage capacitor and a switch for controlling the charging on / off of the second energy storage capacitor, and the capacitance value of the second energy storage capacitor is greater than that of the first energy storage capacitor; A microcontroller unit circuit, which is connected to the coil, the first energy storage module, and the second energy storage module through the voltage output node; A drive circuit, which is connected to the microcontroller unit circuit and is connected to the second energy storage capacitor through the voltage output node; wherein, when the NFC device approaches the coil of the antenna module, an energy transfer channel is established between the antenna module and the NFC device through the coil, and the coil generates a first energy through magnetic field resonance to the first energy storage capacitor for the first energy storage and provides it to the microcontroller unit circuit to start the normal operation of the microcontroller unit circuit; When the NFC device detects an antenna feedback signal fed back by the antenna module, a communication transmission channel is established between the antenna module and the NFC device through the coil, and the NFC device transmits an NFC carrier signal to the antenna module through the communication transmission channel. The coil of the antenna module generates a second energy through receiving the NFC carrier signal to the second energy storage capacitor for the second energy storage, wherein the second energy is greater than the first energy, and the microcontroller unit circuit receives the instruction sent by the NFC chip and transmits it to a drive circuit, and the drive circuit receives the instruction and drives a load through the energy released by the second energy storage capacitor; wherein, the switch of the second energy storage module includes a first transistor switch and a second transistor switch, and the second energy storage module further includes a second diode, wherein the first transistor switch, its first end is connected to the microcontroller unit circuit, its second end is connected to the first end of the second transistor switch, and its third end is grounded; the second transistor switch, its second end is connected to the voltage output node, and its third end is connected to the positive end of the second energy storage capacitor; the negative end of the second energy storage capacitor is connected to the third end of the first transistor and is grounded at the same time; the positive end of the second diode is connected to the positive end of the second energy storage capacitor, and the negative end of the second diode is connected to the voltage output node and is connected to the microcontroller unit circuit and the drive circuit; wherein, during the first energy storage, the microcontroller unit circuit makes the second energy storage capacitor in a charging-off state of not absorbing energy by turning off the first transistor switch and the second transistor switch; during the second energy storage, the microcontroller unit circuit makes the second energy storage capacitor in a charging-on state of absorbing energy by turning on the first transistor switch and the second transistor switch.

5. The NFC-based power supply circuit according to claim 4, characterized in that, it further comprises: a rectifier circuit having two input nodes and two output nodes, the two input nodes being respectively connected to two ends of the coil, one of the two output nodes being connected to the voltage output node, and the other of the two output nodes being grounded, wherein the generated first energy and second energy are converted into regulated DC electrical energy by the rectifier circuit and transmitted to the first energy storage capacitor and the second energy storage capacitor.

6. The NFC-based power supply circuit according to claim 5, characterized in that, the rectifier circuit is a full-bridge rectifier circuit composed of four first diodes; and / or, the positive terminal of the first energy storage capacitor is connected to the voltage output node, and the negative terminal of the first energy storage capacitor is connected to the other of the two output nodes of the rectifier circuit and is grounded at the same time.

7. The NFC-based power supply circuit according to claim 6, characterized in that, when the micro-control unit circuit detects an increase in the output voltage of the coil at the voltage output node, it controls the switch to turn on so that the second energy storage capacitor is in a charging-on state of absorbing energy for second energy storage; and / or, when the second energy storage capacitor reaches a matching state sufficient to drive the load during second energy storage, the micro-control unit circuit starts to respond to receive the instruction from the NFC chip.

8. A passive electronic terminal, characterized in that, it has the power supply circuit according to any one of claims 4 to 7.

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