Passive NFC (Near Field Communication) module of ink screen
By using a passive NFC module design and electromagnetic induction power supply, the problems of increased cost and leakage caused by built-in batteries are solved, enabling low-cost and environmentally friendly NFC module applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- BEIJING DIGITAL CHINA CLOUD COMPUTING CO LTD
- Filing Date
- 2025-03-26
- Publication Date
- 2026-04-17
AI Technical Summary
In existing technologies, the built-in battery in NFC modules increases costs and poses risks of leakage and electrical leakage.
Design a passive NFC module that utilizes an NFC control module, a voltage monitoring module, a DC-DC conversion module, a power conversion module, and a connector to generate electrical energy through electromagnetic induction to power the module. Combined with a filtering circuit and a rectifier circuit to optimize energy conversion, it achieves the goal of not requiring local power support.
It reduces costs, avoids leakage and electrical leakage problems, improves portability and applicability, simplifies production and maintenance, and conforms to the concept of green environmental protection.
Smart Images
Figure CN224137878U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of e-ink screen technology, and in particular to a passive NFC module for e-ink screens. Background Technology
[0002] NFC (Near Field Communication) is developed based on contactless radio frequency identification (RFID) technology and combined with wireless interconnection technology. It provides a very secure and fast communication method for various electronic products that are becoming increasingly common in our daily lives. The "near field" in the Chinese name NFC refers to radio waves that are near an electromagnetic field.
[0003] Existing technologies, due to their internal circuitry, require power and typically incorporate a built-in battery. On one hand, using a battery as a component increases the cost of the device; on the other hand, incorporating a battery not only increases its weight but also poses risks such as leakage and electrical leakage. Utility Model Content
[0004] The main purpose of this invention is to propose a passive NFC module for e-ink screens, which aims to solve the problems of increased cost due to built-in batteries and potential leakage of batteries in the prior art.
[0005] To achieve the above objectives, this utility model proposes a passive NFC module for an e-ink screen, comprising an NFC control module, a voltage monitoring module, a DC-DC conversion module, a power conversion module, and a connector. The NFC control module is connected to the voltage monitoring module, the DC-DC conversion module, and the connector, respectively, and the power conversion module is connected to the voltage monitoring module and the connector, respectively.
[0006] The voltage monitoring module is used to monitor the output voltage of the power conversion module in real time and feed the monitoring results back to the NFC control module.
[0007] The DC-DC conversion module is used to convert the voltage output by the power conversion module into the operating voltage of the e-ink screen;
[0008] The power conversion module is connected to the connector and is used to convert the electrical energy generated by the NFC control module through electromagnetic induction into DC voltage, and to provide power to the NFC control module, the voltage monitoring module and the DC-DC conversion module;
[0009] The connector is used to physically connect the passive NFC module to the e-ink screen and to transmit power and signals.
[0010] In one embodiment, the passive NFC module further includes an antenna and a first filtering circuit connected in sequence. The first filtering circuit is connected to the NFC control module. The antenna is used to convert radio frequency signals into electrical energy and transmit the electrical energy to the first filtering circuit. The first filtering circuit is used to filter the signals received by the antenna.
[0011] In one embodiment, the first filter circuit includes a first capacitor and a second capacitor, which are connected in parallel, and the first capacitor and the second capacitor are respectively connected to the antenna.
[0012] In one embodiment, the passive NFC module further includes a rectifier circuit, the output of which is connected to the input of the DC-DC converter module, and the input of which is connected to the antenna.
[0013] In one embodiment, the rectifier circuit includes a rectifier bridge, a first switching transistor, a second switching transistor, and a second filter circuit. The two input terminals of the rectifier bridge are connected to the antenna, the output terminal of the rectifier bridge is connected to the drain of the first switching transistor, the source of the first switching transistor is connected to the second filter circuit, the gate of the first switching transistor is connected to the drain of the second switching transistor, the gate of the second switching transistor is connected to the NFC control module, and the output terminal of the second filter circuit is connected to the DC-DC conversion module.
[0014] In one embodiment, the DC-DC conversion module includes a step-down chip, a first inductor, a third capacitor, and a fourth capacitor. One end of the first inductor is connected to the step-down chip, and the other end of the first inductor is connected to the third capacitor and the fourth capacitor, respectively.
[0015] In one embodiment, the passive NFC module further includes a screen driving circuit, which is connected to the connector and is used to drive the e-ink screen.
[0016] In one embodiment, the screen driving circuit includes a second inductor and a third switching transistor. One end of the second inductor is connected to the DC-DC conversion module, and the other end of the second inductor is connected to the drain of the third switching transistor. The gate of the third switching transistor is connected to the connector.
[0017] In one embodiment, the first switch, the second switch, and the third switch are N-channel MOSFETs.
[0018] In one embodiment, the passive NFC module further includes an LED indicator light, which is connected to the DC-DC conversion module.
[0019] This invention achieves simultaneous image transmission between a mobile phone and an e-ink screen without the need for a local power supply by employing an NFC control module, a voltage monitoring module, a DC-DC conversion module, a power conversion module, and a connector. This eliminates the need for a built-in battery, reducing costs and preventing leakage issues. The voltage monitoring module monitors the output voltage of the power conversion module in real time and feeds the monitoring results back to the NFC control module. The DC-DC conversion module converts the voltage output by the power conversion module into the operating voltage of the e-ink screen. The power conversion module, connected to the connector, converts the electrical energy generated by the NFC control module through electromagnetic induction into DC voltage, providing power to the NFC control module, the voltage monitoring module, and the DC-DC conversion module. The connector physically connects the passive NFC module to the e-ink screen, transmitting power and signals. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0021] Figure 1 This is a schematic diagram of a passive NFC module for an e-ink display.
[0022] Figure 2 Diagram of the antenna and the first filter circuit;
[0023] Figure 3 This is a diagram of the rectifier circuit;
[0024] Figure 4 This is a circuit diagram of a DC-DC converter module;
[0025] Figure 5 This is a circuit diagram of the screen driver.
[0026] Figure 6 This is the connector circuit diagram;
[0027] Figure 7 This is the circuit diagram for the NFC control module.
[0028] Explanation of icon numbers:
[0029] 1. NFC control module; 2. Voltage monitoring module; 3. DC-DC conversion module; 4. Power conversion module; 5. Connector; 6. Antenna; 7. First filter circuit; C1, first capacitor; C2, second capacitor; 8. Rectifier circuit; 81. Rectifier bridge; Q1, first switching transistor; Q2, second switching transistor; 82. Second filter circuit; U2, step-down chip; L2, first inductor; C10, third capacitor; C11, fourth capacitor; 9. Screen driver circuit; L3, second inductor; Q3, third switching transistor; 10. LED indicator.
[0030] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0032] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.
[0033] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, if the word "and / or" appears throughout the text, it means including three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.
[0034] This invention proposes a passive NFC module for e-ink displays.
[0035] In the embodiments of this utility model, such as Figure 1 , Figure 6 , Figure 7 As shown, the passive NFC module includes an NFC control module 1, a voltage monitoring module 2, a DC-DC conversion module 3, a power conversion module 4, and a connector 5. The NFC control module 1 is connected to the voltage monitoring module 2, the DC-DC conversion module 3, and the connector 5. The power conversion module 4 is connected to the voltage monitoring module 2 and the connector 5. The voltage monitoring module 2 monitors the output voltage of the power conversion module 4 in real time and feeds back the monitoring results to the NFC control module 1. The DC-DC conversion module 3 converts the voltage output by the power conversion module 4 into the operating voltage of the e-ink screen. The power conversion module 4 is connected to the connector 5 and converts the electrical energy generated by the NFC control module 1 through electromagnetic induction into DC voltage, providing power to the NFC control module 1, the voltage monitoring module 2, and the DC-DC conversion module 3. The connector 5 physically connects the passive NFC module to the e-ink screen and transmits power and signals.
[0036] This invention achieves synchronous image transmission between a mobile phone and an e-ink screen without the need for local power support by employing an NFC control module 1, a voltage monitoring module 2, a DC-DC conversion module 3, a power conversion module 4, and a connector 5. This eliminates the need for a built-in battery, reducing costs and preventing leakage issues. The voltage monitoring module 2 monitors the output voltage of the power conversion module 4 in real time and feeds the monitoring results back to the NFC control module 1. The DC-DC conversion module 3 converts the voltage output by the power conversion module 4 into the operating voltage of the e-ink screen. The power conversion module 4 is then connected to the connector 5 to convert the electrical energy generated by the NFC control module 1 through electromagnetic induction into DC voltage, providing power to the NFC control module 1, the voltage monitoring module 2, and the DC-DC conversion module 3. The connector 5 physically connects the passive NFC module to the e-ink screen and transmits power and signals.
[0037] This passive NFC module is designed based on Near Field Communication (NFC) technology and electromagnetic induction principles. It communicates with external NFC reading / writing devices (such as mobile phones) through the NFC control module 1, and uses energy generated by electromagnetic induction to power both the module itself and the connected e-ink display. Its working principle is as follows:
[0038] The NFC control module 1 is responsible for communicating with external NFC devices (such as mobile phones). When an external NFC device approaches, the NFC control module 1 receives energy and data signals through electromagnetic induction. When an external NFC device approaches, the alternating electromagnetic field it generates induces a current in the antenna 6 of the NFC control module 1.
[0039] The induced current is converted into DC voltage by the power conversion module 4, powering the entire passive NFC module. The voltage monitoring module 2 monitors the output voltage of the power conversion module 4 in real time. The monitoring results are fed back to the NFC control module 1 to ensure the voltage remains stable within a safe range. If the voltage is abnormal (too high or too low), the NFC control module 1 can take protective measures, such as reducing power consumption or stopping data transmission. The DC-DC conversion module 3 converts the voltage output from the power conversion module 4 into the operating voltage required by the e-ink screen. Since the operating voltage of the e-ink screen may not match the voltage of the NFC module, the DC-DC conversion module 3 ensures that the e-ink screen can operate stably.
[0040] This embodiment uses a 24-pin FPC connector 5 to connect to the e-ink screen. Power and signals are transmitted through connector 5 to ensure that the e-ink screen can receive data and display normally. This embodiment features a passive design, requiring no external power supply. The passive NFC module obtains energy from external NFC devices (such as mobile phones) through electromagnetic induction, eliminating the need for additional batteries or power adapters, reducing module complexity and cost, while improving portability and applicability. The power conversion module 4 and DC-DC conversion module 3 work together to ensure that the energy generated by electromagnetic induction is used efficiently. The voltage monitoring module 2 monitors the voltage in real time to prevent voltage abnormalities from damaging the module and e-ink screen. Since no battery or external power supply is required, the e-ink screen device can be designed to be thinner and more compact. The design of connector 5 simplifies the integration of the module and the e-ink screen, reducing production and maintenance costs.
[0041] NFC technology itself is characterized by low power consumption, and combined with a passive design, it further reduces overall energy consumption. Eliminating the need for batteries also avoids the environmental impact of battery disposal, aligning with green environmental protection principles. The NFC control module 1 can quickly receive data transmitted from external devices and transmit it to the e-ink screen in real time via connector 5. The voltage monitoring module 2 ensures the system operates under a stable voltage, improving the module's reliability. NFC communication has a short range and supports encrypted transmission, effectively preventing data theft or interference.
[0042] like Figure 2 As shown, the passive NFC module further includes an antenna 6 and a first filtering circuit 7 connected in sequence. The first filtering circuit 7 is connected to the NFC control module 1. The antenna 6 is used to convert radio frequency signals into electrical energy and transmit the electrical energy to the first filtering circuit 7. The first filtering circuit 7 is used to filter the signals received by the antenna 6. The first filtering circuit 7 includes a first capacitor C1 and a second capacitor C2, which are connected in parallel. The first capacitor C1 and the second capacitor C2 are respectively connected to the antenna 6.
[0043] Antenna 6, as the core component for energy harvesting, efficiently converts radio frequency signals emitted by external NFC devices (such as mobile phones) into electrical energy. Optimizing the design of antenna 6 (such as size, shape, and materials) improves the efficiency of electromagnetic induction, ensuring stable operation of the passive NFC module at longer distances or under weaker signals, thus enhancing its energy harvesting capability and providing a more stable power supply for the module and the connected e-ink screen. The first filter circuit 7 filters the signal received by antenna 6, removing noise and interference signals. The filtered signal is cleaner, improving the data parsing accuracy of the NFC control module 1 and reducing data transmission errors. In complex electromagnetic environments (such as shopping malls and warehouses), the first filter circuit 7 effectively avoids external interference, ensuring communication reliability. Optimizing the collaborative work of antenna 6 and the first filter circuit 7 improves the sensitivity of radio frequency signal reception, enabling the passive NFC module to communicate with external devices at greater distances (e.g., approaching the theoretical maximum NFC distance of 10 cm) without communication failure due to signal attenuation. The first filter circuit 7 reduces interference from invalid signals, preventing the NFC control module 1 from consuming extra energy to process noise signals.
[0044] The combination of antenna 6 and the first filter circuit 7 ensures efficient conversion and stable transmission of radio frequency signals. Under conditions of voltage fluctuations or external interference, the first filter circuit 7 can maintain a stable output, preventing the passive NFC module from malfunctioning due to signal instability. The design of antenna 6 and the first filter circuit 7 can be integrated into existing passive NFC modules without the need for additional complex components. Due to the improved energy harvesting efficiency and signal quality, this module can be applied to more complex environments.
[0045] like Figure 3 As shown, the passive NFC module further includes a rectifier circuit 8. The output terminal of the rectifier circuit 8 is connected to the input terminal of the DC-DC conversion module 3, and the input terminal of the rectifier circuit 8 is connected to the antenna 6. The rectifier circuit 8 includes a rectifier bridge 81, a first switch Q1, a second switch Q2, and a second filter circuit 82. The two input terminals of the rectifier bridge 81 are connected to the antenna 6, the output terminal of the rectifier bridge 81 is connected to the drain of the first switch Q1, the source of the first switch Q1 is connected to the second filter circuit 82, the gate of the first switch Q1 is connected to the drain of the second switch Q2, the gate of the second switch Q2 is connected to the NFC control module 1, and the output terminal of the second filter circuit 82 is connected to the DC-DC conversion module 3.
[0046] The rectifier circuit 8 converts the alternating current (AC) received by the antenna 6 into direct current (DC), providing a stable input power supply for the subsequent DC-DC conversion module 3. Through the coordinated operation of the rectifier bridge 81 and the switching transistors, the rectifier circuit 8 can efficiently convert radio frequency signals into electrical energy, reducing energy loss. The design of the first switching transistor Q1 and the second switching transistor Q2 allows the rectifier circuit 8 to dynamically adjust its operating state according to the instructions of the NFC control module 1. When the NFC control module 1 detects that the voltage is too high or too low, it can adjust the output of the rectifier circuit 8 by controlling the on / off state of the switching transistors to ensure power supply stability.
[0047] The second filter circuit 82 further filters the rectified DC power, removing high-frequency noise and ripple. The filtered DC power is cleaner and can provide a stable input voltage for the DC-DC converter module 3, avoiding system failures caused by power fluctuations. The tight integration of the rectifier circuit 8 with the antenna 6 and the DC-DC converter module 3 simplifies the overall structure of the module. The efficient energy conversion and dynamic power management mechanism of the rectifier circuit 8 reduces energy loss during transmission and conversion. The design of the rectifier circuit 8 ensures stable power output, providing a stable DC power supply to the DC-DC converter module 3 even under conditions of large input voltage fluctuations.
[0048] like Figure 4 As shown, the DC-DC conversion module 3 includes a step-down chip U2, a first inductor L2, a third capacitor C10, and a fourth capacitor C11. One end of the first inductor L2 is connected to the step-down chip U2, and the other end of the first inductor L2 is connected to the third capacitor C10 and the fourth capacitor C11, respectively. The step-down chip U2 can convert the higher voltage output by the rectifier circuit 8 into the operating voltage required by the e-ink screen.
[0049] The first inductor L2, the third capacitor C10, and the fourth capacitor C11 effectively smooth the output voltage of the buck converter U2. The combination of the buck converter U2 and the filter network ensures stable operation of the DC-DC converter module 3 under various load conditions. Even if the input voltage or load current changes, the module can still provide a stable output voltage, improving the system's reliability and durability. The high-efficiency conversion of the buck converter U2 and the optimized design of the filter network reduce energy loss during conversion and transmission.
[0050] like Figure 5As shown, the passive NFC module also includes a screen driving circuit 9, which is connected to the connector 5. The screen driving circuit 9 is used to drive the e-ink screen. The screen driving circuit 9 includes a second inductor L3 and a third switch Q3. One end of the second inductor L3 is connected to the DC-DC conversion module 3, and the other end of the second inductor L3 is connected to the drain of the third switch Q3. The gate of the third switch Q3 is connected to the connector 5.
[0051] The screen driver circuit 9, through the coordinated operation of the second inductor L3 and the third switch Q3, efficiently converts the voltage output from the DC-DC converter module 3 into a driving signal suitable for the e-ink screen. Controlled by the third switch Q3, the screen driver circuit 9 dynamically adjusts the driving current according to the display requirements of the e-ink screen. This dynamic adjustment mechanism reduces unnecessary energy loss and extends the operating time of the passive NFC module after a single energy acquisition. The second inductor L3 acts as a filter and energy storage unit in the driver circuit, smoothing the driving signal and reducing the impact of voltage fluctuations on the e-ink screen. This design ensures that the e-ink screen does not flicker or distort during display, improving display quality. The tight integration of the screen driver circuit 9 with the DC-DC converter module 3 and connector 5 simplifies the overall structure of the module.
[0052] The screen driver circuit 9 is designed to ensure stable display of the e-ink screen under various operating conditions. Even if the input voltage or load current changes, the screen driver circuit 9 can still provide a stable drive signal, improving the reliability and durability of the system. By controlling the on / off state of the third switch Q3, the screen driver circuit 9 can support multiple display modes of the e-ink screen.
[0053] The first switch Q1, the second switch Q2, and the third switch Q3 are N-channel MOSFETs. An N-channel MOSFET is turned on when the gate voltage is higher than the source voltage and the voltage difference is greater than the threshold voltage (Vgs>Vth); and turned off when the gate voltage is lower than the threshold voltage.
[0054] The passive NFC module also includes an LED indicator 10, which is connected to the DC-DC conversion module 3. The LED indicator 10 can intuitively display the working status of the passive NFC module, such as whether an NFC signal has been successfully received or whether data transmission has been completed.
[0055] It should be noted that the NFC control module 1 described in this utility model is existing technology, and the improvement of this utility model does not lie in the technology of this module itself.
[0056] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of this utility model. For those skilled in the art, this utility model can have various modifications, combinations, and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of the claims of this utility model.
Claims
1. A passive NFC module of an ink screen, characterized in that, It includes an NFC control module, a voltage monitoring module, a DC-DC conversion module, a power conversion module, and a connector. The NFC control module is connected to the voltage monitoring module, the DC-DC conversion module, and the connector, respectively. The power conversion module is connected to the voltage monitoring module and the connector, respectively. The voltage monitoring module is used to monitor the output voltage of the power conversion module in real time and feed the monitoring results back to the NFC control module. The DC-DC conversion module is used to convert the voltage output by the power conversion module into the operating voltage of the e-ink screen; The power conversion module is connected to the connector and is used to convert the electrical energy generated by the NFC control module through electromagnetic induction into DC voltage, and to provide power to the NFC control module, the voltage monitoring module and the DC-DC conversion module; The connector is used to physically connect the passive NFC module to the e-ink screen and to transmit power and signals.
2. The passive NFC module of claim 1, wherein, The passive NFC module further includes an antenna and a first filtering circuit connected in sequence. The first filtering circuit is connected to the NFC control module. The antenna is used to convert radio frequency signals into electrical energy and transmit the electrical energy to the first filtering circuit. The first filtering circuit is used to filter the signals received by the antenna.
3. The passive NFC module of claim 2, wherein, The first filter circuit includes a first capacitor and a second capacitor, which are connected in parallel, and are respectively connected to the antenna.
4. The passive NFC module of claim 2, wherein, The passive NFC module also includes a rectifier circuit, the output of which is connected to the input of the DC-DC converter module, and the input of which is connected to the antenna.
5. The passive NFC module of claim 4, wherein, The rectifier circuit includes a rectifier bridge, a first switching transistor, a second switching transistor, and a second filter circuit. The two input terminals of the rectifier bridge are connected to the antenna, the output terminal of the rectifier bridge is connected to the drain of the first switching transistor, the source of the first switching transistor is connected to the second filter circuit, the gate of the first switching transistor is connected to the drain of the second switching transistor, the gate of the second switching transistor is connected to the NFC control module, and the output terminal of the second filter circuit is connected to the DC-DC conversion module.
6. The passive NFC module of claim 4, wherein, The DC-DC conversion module includes a step-down chip, a first inductor, a third capacitor, and a fourth capacitor. One end of the first inductor is connected to the step-down chip, and the other end of the first inductor is connected to the third capacitor and the fourth capacitor, respectively.
7. The passive NFC module of claim 5, wherein, The passive NFC module also includes a screen driving circuit, which is connected to the connector and is used to drive the e-ink screen.
8. The passive NFC module of claim 7, wherein, The screen driving circuit includes a second inductor and a third switching transistor. One end of the second inductor is connected to the DC-DC conversion module, and the other end of the second inductor is connected to the drain of the third switching transistor. The gate of the third switching transistor is connected to the connector.
9. The passive NFC module of claim 8, wherein, The first switch, the second switch, and the third switch are N-channel MOSFETs.
10. The passive NFC module as described in claim 1, characterized in that, The passive NFC module further comprises an LED indicator light connected with the DC-DC conversion module.