A smart card

Abstract

This invention relates to a smart card, comprising: a battery, a controller, a charging module, a communication module, and a wired interface module connected to both the charging module and the communication module. The wired interface module is connected to an external charging and communication device via a signal line and is used to receive management signals from the external charging and communication device. These management signals include DC charging signals and / or high-frequency AC communication signals. The charging module, when a DC charging signal is present in the management signal, separates the DC charging signal from the management signal and processes it to charge the battery. The communication module, when a high-frequency AC communication signal is present in the management signal, separates the high-frequency AC communication signal from the management signal, processes it to obtain a digital communication signal, and sends the digital communication signal to the controller. By implementing this invention, charging and communication of the contact-type composite card can be performed simultaneously, improving operator efficiency.

Description

Technical Field

[0001] This invention relates to the field of composite card charging and communication technology, and in particular to a smart card. Background Technology

[0002] Composite access cards are currently widely used in parking lots, highway toll stations, and commercial access control systems. Composite cards have the advantages of being small, thin, and portable. At the same time, composite access cards are usually active cards with built-in batteries, and their usage is high, requiring low design costs.

[0003] Currently, toll stations issue a large number of cards daily. Wireless charging is inefficient and takes a long time, and it cannot charge a large number of cards at the same time. Designing a wireless charging method would interfere with the contactless communication of existing dual-interface cards, resulting in a low card issuance success rate. In addition, conventional contact charging cannot be carried out simultaneously with communication. It is necessary to switch the charging and communication circuit states to achieve this, which results in high cost and low efficiency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a smart card that addresses at least one deficiency of the related technologies mentioned in the background: conventional contact-type composite access cards cannot charge and communicate simultaneously.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to provide a smart card, including a battery, a controller, a charging module, a communication module, and a wired interface module respectively connected to the charging module and the communication module;

[0006] The wired interface module is connected to an external charging communication device via a signal line and is used to receive management signals from the external charging communication device. The management signals include DC charging signals and / or high-frequency AC communication signals.

[0007] The charging module is used to separate the DC charging signal from the management signal when the management signal contains a DC charging signal, and to charge the battery by processing the DC charging signal.

[0008] The communication module is used to separate the high-frequency AC communication signal from the management signal when the management signal contains a high-frequency AC communication signal, and to obtain a digital communication signal by processing the high-frequency AC communication signal, and to send the digital communication signal to the controller.

[0009] Preferably, in the smart card of the present invention, the charging module includes a low-pass filter and a charging management unit, wherein,

[0010] The low-pass filter is used to filter out the high-frequency AC communication signal from the management signal and output the DC charging signal;

[0011] The charging management unit is connected to the low-pass filter and is used to process the DC charging signal and charge the battery.

[0012] Preferably, in the smart card of the present invention, the low-pass filter includes a first inductor and a first capacitor;

[0013] The first inductor and the first capacitor are connected in parallel.

[0014] Preferably, in the smart card of the present invention, the charging module further includes:

[0015] A battery protection unit is used to protect the battery.

[0016] Preferably, in the smart card of the present invention, a voltage regulator unit is used to regulate the output voltage of the battery in order to provide an operating voltage for the controller.

[0017] Preferably, in the smart card of the present invention, the communication module includes a DC isolator, a coupling unit, and a channel unit;

[0018] The DC isolator is used to filter out the DC charging signal from the management signal and output the high-frequency AC communication signal.

[0019] The coupling unit is used to couple the high-frequency AC communication signal by electromagnetic induction to obtain a two-end high-frequency differential signal.

[0020] The channel unit is used to convert the dual-end high-frequency differential signal into a digital communication signal.

[0021] Preferably, in the smart card of the present invention, the coupling unit includes: a second inductor, a third inductor, a fourth inductor, and a fifth inductor, wherein the second inductor and the third inductor are connected in series to form a first single-ended winding coil, the fourth inductor and the fifth inductor are connected in series to form a second single-ended winding coil, and the first single-ended winding coil and the second single-ended winding coil are placed side by side.

[0022] Preferably, in the smart card of the present invention, the second inductor and the fourth inductor are placed close to each other side by side;

[0023] The third inductor and the fifth inductor are placed close to each other and side by side.

[0024] Preferably, in the smart card of the present invention, the communication module includes a dual-end matching unit;

[0025] The dual-ended matching unit includes a second capacitor;

[0026] The second capacitor and the second single-ended winding coil form a parallel resonant circuit to match the port impedance.

[0027] Preferably, in the smart card of the present invention, the channel unit includes a dual-interface channel chip that supports both contactless and contact interfaces.

[0028] By implementing this invention, the following beneficial effects are achieved:

[0029] This invention discloses a smart card that, by incorporating a charging module, a wired interface module, and a communication module, enables the input of management signals from the wired interface module. When a DC charging signal is present in the management signal, the charging module is activated to charge the smart card's battery. When a high-frequency AC communication signal is present in the management signal, the communication module is activated to process the high-frequency AC communication signal and obtain a communication signal. This communication signal is then input into a controller to complete communication. By implementing this invention, the smart card battery is rechargeable. In the current environment of rapidly increasing gantry antennas, the card can be reused, saving customers procurement costs. Furthermore, the design allows for simultaneous contact charging and communication, improving operator efficiency. Attached Figure Description

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0031] Figure 1 This is a block diagram of the smart card of the present invention;

[0032] Figure 2 This is a schematic diagram of the dual-contact design of the present invention;

[0033] Figure 3 This is a schematic diagram of the three-touch electrode design of the present invention;

[0034] Figure 4 This is a block diagram of the internal charging and communication interface logic unit of the smart card of the present invention;

[0035] Figure 5 This is a schematic diagram of the low-pass filter design of the present invention;

[0036] Figure 6 This is a logic diagram of the charging management unit of the present invention;

[0037] Figure 7 This is a schematic diagram of the coupling unit and the double-ended matching unit design of the present invention. Detailed Implementation

[0038] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0039] It should be noted that the flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0040] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0041] In this embodiment, as Figure 1 As shown, the present invention provides a smart card, including a battery, a controller, a charging module M1, a communication module M3, and a wired interface module M2 connected to the charging module M1 and the communication module M3 respectively.

[0042] The wired interface module M2 is connected to an external charging communication device via a signal line and is used to receive management signals from the external charging communication device. The management signals include DC charging signals and / or high-frequency AC communication signals.

[0043] The charging module M1 is used to separate the DC charging signal from the management signal when the DC charging signal is present in the management signal, and to charge the battery by processing the DC charging signal.

[0044] The communication module M3 is used to separate the high-frequency AC communication signal from the management signal when there is a high-frequency AC communication signal in the management signal, and to obtain the digital communication signal by processing the high-frequency AC communication signal, and then send the digital communication signal to the controller.

[0045] Specifically:

[0046] The wired interface module M2 of the smart card can be charged and communicated via direct contact. The charging and communication contacts are designed with either two contacts or a symmetrical three-contact configuration. For example... Figure 2 As shown, a dual-contact design is adopted, such as Figure 3 As shown, a three-contact design is adopted. Contact A is positioned in the center of the short side, and the distance between contact B and contact A is d = 1.252 * N (mm) (where N = 1, 2, 3...n). The contact positions can be adjusted according to actual conditions.

[0047] Charging status: Option 1, contact A is defined as positive power, and contact B is defined as ground. Option 2, contact A is defined as ground, and contact B is defined as positive power.

[0048] Communication status: Option 1, contact A is defined as signal input, and contact B is defined as signal ground. Option 2, contact A is defined as signal ground, and contact B is defined as signal input.

[0049] Scheme 1 and Scheme 2 differ only in the definition of contact function and structural design; the specific hardware and software design and implementation are identical, and the positive power input and signal input must be from the same contact. The following is a detailed design description for Scheme 1, a typical application.

[0050] Combination such as Figure 4 As shown, a positive voltage is input through contact A to enable the power management chip, and the battery charging current and charging cut-off voltage are adjusted by the adjustable resistor of the power management chip. At the same time, a positive voltage is input through contact A to enable the dual-channel communication chip, at which point both the DC charging line and the high-frequency signal communication line are turned on.

[0051] The charging device inputs a DC charging signal superimposed with a high-frequency AC communication signal AD through contact A. The superimposed signal AD is filtered by a low-frequency filter F1 to remove the high-frequency AC communication signal, and outputs a DC charging signal D1. The DC power supply D1 is input to the charging management unit B1. If the charging logic determines that the charging conditions are met, it outputs a charging voltage D2. D2 is input to the battery protection unit P1 to start providing battery charging current.

[0052] In this embodiment, the charging module M1 includes a low-pass filter F1 and a charging management unit B1, wherein,

[0053] The low-pass filter F1 is used to filter out high-frequency AC communication signals from the management signal and output a DC charging signal.

[0054] The charging management unit B1 is connected to the low-pass filter F1 and is used to process the DC charging signal and charge the battery.

[0055] Furthermore, such as Figure 5 As shown, the low-pass filter includes a first inductor L1 and a first capacitor C1;

[0056] The first inductor L1 and the first capacitor C1 are connected in parallel.

[0057] The low-pass filter F1 is connected in parallel with the first inductor L1 and the first capacitor C1. The wire-wound inductor L1 suppresses high-frequency AC signals and allows DC signals to pass through. C1 blocks DC signals and allows high-frequency AC signals to pass to ground, thereby achieving the purpose of suppressing high-frequency AC signals and outputting DC signals.

[0058] Charging management unit B1 is used to set the maximum charging current, charging cut-off current, input overvoltage protection, charging status indication, etc. It enters the charging state by judging the states of input voltage D1 and battery voltage D2. The judgment logic is as follows: Figure 6 As shown.

[0059] The charging management unit B1 determines the input voltage D1 to enable charging detection. When the input voltage D1 is less than the overvoltage protection threshold, it returns to continue enabling charging detection. When the input voltage D1 is greater than or equal to the overvoltage protection threshold, it determines whether the battery voltage D2 is normal. When the battery voltage D2 is abnormal, it returns to the input voltage D1 threshold detection. When the battery voltage D2 is normal, charging begins.

[0060] During charging, the system enters different charging states based on the battery voltage D2 and provides charging status indications. These charging states include: trickle charging, constant current charging, and constant voltage charging.

[0061] Among them, such as Figure 6 As shown, when the battery voltage D2 is less than 2.8V, it enters trickle charging state to charge until the battery voltage D2 is greater than 2.8V, then enters the next state.

[0062] When the battery voltage D2 is determined to be greater than 2.8V and less than 4.1V, it enters constant current charging state to charge until the battery voltage D2 is greater than 4.1V, then enters the next state.

[0063] When the battery voltage D2 is determined to be greater than 4.1V, it enters constant voltage charging state to charge until the charging current reaches the cutoff current, at which point charging stops.

[0064] Furthermore, in this embodiment, the charging module M1 further includes:

[0065] Battery protection unit P1 is used to protect the battery. Battery protection unit P1 includes an overcharge and over-discharge voltage protection chip and a rechargeable battery.

[0066] In addition, this embodiment also includes:

[0067] The voltage regulator unit P2 is used to regulate the output voltage of the battery in order to provide the operating voltage for the controller.

[0068] In addition, in this embodiment, the communication module M3 includes a DC isolator F2, a coupling unit T1, and a channel unit T2;

[0069] DC isolator F2 is used to filter out the DC charging signal from the management signal and output a high-frequency AC communication signal A1; and the amplitude of the high-frequency AC communication signal is not significantly attenuated. DC isolator F2 replaces the DC blocking capacitor, which is low in cost, small in size, and high in efficiency.

[0070] The coupling unit T1 is used to couple high-frequency AC communication signals through electromagnetic induction to obtain a two-end high-frequency differential signal.

[0071] Channel unit T2 is used to convert dual-end high-frequency differential signals into digital communication signals.

[0072] Furthermore, the coupling unit T1 is a wire-wound inductor array design, which is small in size and low in cost, such as... Figure 7 As shown, the coupling unit T1 includes: a second inductor L2, a third inductor L3, a fourth inductor L4, and a fifth inductor L5. The second inductor L2 and the third inductor L3 are connected in series to form a first single-ended winding coil G1, and the fourth inductor L4 and the fifth inductor L5 are connected in series to form a second single-ended winding coil G2. The first single-ended winding coil G1 and the second single-ended winding coil G2 are placed side by side.

[0073] The high-frequency AC communication signal A1 output by the DC isolator F2 is input into the first single-ended winding coil G1 to form an electromagnetic field. Through the principle of electromagnetic induction, the signal is induced to the second single-ended winding coil G2 to form signal coupling. The coupled signal outputs differential signals AP and AN.

[0074] The purpose of connecting wire-wound inductors in series is to increase the mutual inductance of the parallel coils by increasing the winding length, thereby coupling to a stronger signal. Multiple inductors can also be connected in series to further enhance the mutual inductance, but due to the size of the card itself, only two wire-wound inductors are listed here.

[0075] Furthermore, the second inductor L2 and the fourth inductor L4 are placed close to each other side by side;

[0076] The third inductor L3 and the fifth inductor L5 are placed close to each other side by side.

[0077] Furthermore, the communication module M3 includes a two-end matching unit B2;

[0078] The dual-ended matching unit B2 includes a second capacitor C2;

[0079] like Figure 7 As shown, the second capacitor C2 and the second single-ended winding coil G2 form a parallel resonant circuit to match the port impedance, realize the transmission of maximum signal energy, and output differential signals AP1 and AN1 to the channel unit T2.

[0080] Furthermore, channel unit T2 includes a dual-interface channel chip supporting both contactless and contact interfaces to achieve interface conversion. Contact interface communication types include IIC, SPI, and UART. Signal S is a TTL-level digital signal after interface conversion, enabling communication with the main controller M.

[0081] The voltage regulator unit P2 is a power supply regulator chip that provides a stable operating voltage to the channel unit T2 and the main controller M for normal operation.

[0082] When channel unit T2 receives a differential signal, it triggers an output interrupt signal. The interrupt signal wakes up the MCU and configures channel unit T2 to channel mode through the interface, starting a large amount of data transmission. When the data transmission is detected to be complete, the MCU sets channel unit T2 to low-power mode and the MCU enters sleep mode.

[0083] By implementing this invention, the following beneficial effects are achieved:

[0084] This invention discloses a smart card that, by incorporating a charging module, a wired interface module, and a communication module, enables the input of management signals from the wired interface module. When a DC charging signal is present in the management signal, the charging module is activated to charge the smart card's battery. When a high-frequency AC communication signal is present in the management signal, the communication module is activated to process the high-frequency AC communication signal and obtain a communication signal. This communication signal is then input into a controller to complete communication. By implementing this invention, the smart card battery is rechargeable. In the current environment of rapidly increasing gantry antennas, the card can be reused, saving customers procurement costs. Furthermore, the design allows for simultaneous contact charging and communication, improving operator efficiency.

[0085] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A smart card, comprising a battery and a controller, characterized in that, include: A charging module, a communication module, and a wired interface module connected to the charging module and the communication module respectively; The wired interface module is connected to an external charging communication device via a signal line and is used to receive management signals from the external charging communication device. The management signals include DC charging signals and / or high-frequency AC communication signals. The positive power contact and the signal input contact of the wired interface module are the same contact. The charging module is used to separate the DC charging signal from the management signal when the management signal contains a DC charging signal, and to charge the battery by processing the DC charging signal. The communication module is used to separate the high-frequency AC communication signal from the management signal when the management signal contains a high-frequency AC communication signal, and to obtain a digital communication signal by processing the high-frequency AC communication signal, and to send the digital communication signal to the controller. The charging module includes a low-pass filter and a charging management unit, wherein, The low-pass filter is used to filter out the high-frequency AC communication signal from the management signal and output the DC charging signal; The charging management unit is connected to the low-pass filter and is used to process the DC charging signal and charge the battery. The communication module includes a DC isolator, a coupling unit, and a channel unit; The DC isolator is used to filter out the DC charging signal from the management signal and output the high-frequency AC communication signal. The coupling unit is used to couple the high-frequency AC communication signal by electromagnetic induction to obtain a two-end high-frequency differential signal. The channel unit is used to convert the dual-end high-frequency differential signal into a digital communication signal.

2. The smart card according to claim 1, characterized in that, The low-pass filter includes a first inductor and a first capacitor; The first inductor and the first capacitor are connected in parallel.

3. The smart card according to claim 1, characterized in that, The charging module also includes: A battery protection unit is used to protect the battery.

4. The smart card according to claim 1, characterized in that, Also includes: A voltage regulator unit is used to regulate the output voltage of the battery in order to provide operating voltage for the controller.

5. The smart card according to claim 1, characterized in that, The coupling unit includes a second inductor, a third inductor, a fourth inductor, and a fifth inductor, wherein the second inductor and the third inductor are connected in series to form a first single-ended winding coil, the fourth inductor and the fifth inductor are connected in series to form a second single-ended winding coil, and the first single-ended winding coil and the second single-ended winding coil are placed side by side.

6. The smart card according to claim 5, characterized in that, The second inductor and the fourth inductor are placed close to each other and side by side; The third inductor is placed close to and side by side with the fifth inductor.

7. The smart card according to claim 5, characterized in that, The communication module includes a dual-end matching unit; The dual-ended matching unit includes a second capacitor; The second capacitor and the second single-ended winding coil form a parallel resonant circuit to match the port impedance.

8. The smart card according to claim 1, characterized in that, The channel unit includes a dual-interface channel chip that supports both contactless and contact interfaces.

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