CN201111122Y - Connection device between double data interface subscriber identification card and non-contact front-end chip - Google Patents

Abstract

The utility model relates to a connection device between a double data interface user identification card and a non-contact front-end chip, which includes a baseband chip, a user identification card, and a non-contact front-end chip connected to each other, and is characterized in that the user identification card includes a second data interface The non-contact front-end chip includes a main control circuit, a control module and a power module; the non-contact front-end chip is connected to the second data interface of the subscriber identification card. The device is simple to implement, the range of user identification cards that can be supported is expanded, the technical cost is reduced, and it is beneficial to the overall promotion of mobile non-contact applications; at the same time, the noise tolerance of the device is significantly improved, and the communication is stable and reliable.

Description

Connection device between double data interface subscriber identification card and non-contact front-end chip

technical field

The utility model relates to a near-field communication NFC terminal connection device, in particular to a connection device between a double data interface user identification card and a non-contact front-end chip.

Background technique

In recent years, the electronic payment business has penetrated into our lives and brought us a lot of convenience, especially in fixed business locations, the electronic payment business based on integrated IC cards has formed a mature technology and a stable market. Since 2006, with the popularization of near-field communication (NFC) technology, mobile payment services based on mobile phones and mobile communication platforms have become a hot topic. The emerging market of near-field communication (NFC) has started, and various solutions emerge in an endless stream.

Shown in Fig. 1 is a kind of near-field communication NFC terminal connection device of prior art, comprises non-contact analog front-end chip, safety module, baseband chip and user identification card; Described non-contact analog front-end chip is the contactless that NXP company produces Analog front-end chip PN511; described safety module is the safety module SmartMX that NXP Company produces, and it is connected with described non-contact analog front-end chip with signal input and output interface S2C mode; Described baseband chip is connected with described non-contact analog front-end chip by line connected to the host interface; the subscriber identification card is connected to the baseband chip through the ISO7816 interface. The security chip handles data storage and security management of non-contact applications; the non-contact analog front-end chip completes the interface conversion between S2C signals and external non-contact signals, and exchanges application data and instructions with the baseband chip. The near-field communication function of this device is realized by a near-field communication module composed of a non-contact analog front-end chip and a security module, which realizes the functions of non-contact card simulation, non-contact reader and point-to-point communication, which requires independent operation of the operation of the security chip business. The emergence of this operator will break the existing mobile communication operation pattern, and has been unanimously opposed by mobile operators. Therefore, this near-field communication NFC terminal connection device cannot meet the actual business requirements.

Another existing technology is a single-wire protocol SWP connection device, which integrates a subscriber identification card and a security module, and uses the C6 interface of the subscriber identification card to connect to a non-contact analog front-end chip through a single-wire protocol.

The single-wire protocol SWP connection device effectively solves the connection problem between the subscriber identification card and the non-contact analog front-end chip, and is compatible with the existing subscriber identification card standards such as ISO7816, TS 102 221, TS102600, etc., and is supported by most manufacturers. plan. But this device has the following disadvantages:

1. Since the C6 interface of the subscriber identification card is defined as a single-wire transmission line, which is a duplex transmission mode, in order to realize data transmission, the subscriber identification card must add a relatively complicated modulation and demodulation circuit, so the hardware and software design requirements for the subscriber identification card High, the device is complicated to realize, and the cost is high;

2. The single-wire protocol SWP connection device requires the user identification card, non-contact analog chip and mobile terminal to be transformed at the same time, which has a great impact on the industrial chain and is difficult to promote and coordinate;

3. Since the C6 interface of the subscriber identification card uses load modulation for two-way communication, it means that the signal of this interface is a quasi-digital signal, and the load modulation signal sent by the subscriber identification card to the non-contact analog front-end chip will convert the single-wire protocol SWP signal The noise margin is reduced, the signal is easily interfered and affects the stability of the communication, and the hardware design (printed circuit board) is difficult for products with very high component density such as mobile terminals.

Utility model content

The purpose of this utility model is to provide a connection device between a user identification card with a double data interface and a non-contact front-end chip, which can simplify the circuit design of the user identification card, reduce manufacturing costs, and realize simple software; The contact analog chip and the mobile terminal are transformed at the same time, which is beneficial to the overall promotion of mobile non-contact applications; it can significantly improve the noise tolerance, thereby improving the stability of communication.

In order to achieve the above object, the technical solution of the present utility model is: a connection device between a dual-data interface subscriber identification card and a non-contact front-end chip, including a baseband chip, a subscriber identification card connected to the baseband chip in the form of an ISO7816 interface, and an ISO7816 interface A non-contact front-end chip connected to the baseband chip and the subscriber identification card respectively. The baseband chip and the subscriber identification card include a power interface, a reset interface, a clock interface, a ground interface and a data interface. It is characterized in that: the subscriber identification card Add a second data interface;

The non-contact front-end chip includes a main control circuit, a control module and a power module;

The main control circuit is respectively connected to the control module and the power module through a bus;

The input terminal of the control module is respectively connected with the reset interface, the clock interface and the data interface of the baseband chip through the signal line, and its output terminal is respectively connected with the reset interface, the clock interface and the second data interface of the subscriber identification card through the signal line. interface connection;

The input end of the power module is connected to the power interface of the baseband chip through a power line, and the output end is connected to the power interface of the subscriber identification card through a power line.

The above-mentioned double data interface subscriber identification card and non-contact front-end chip connection device, wherein, the data interface and the second data interface of the subscriber identification card are pure digital data interfaces for half-duplex communication.

The connection device between the above-mentioned dual data interface subscriber identification card and the non-contact front-end chip, wherein the control module includes a clock switching control circuit, a reset switching control circuit, a baseband monitoring circuit, a card simulation mode control circuit and a subscriber identification card interface circuit;

The input end of the clock switching control circuit is connected with the clock interface of the baseband chip, receives the baseband clock signal and the contactless clock signal, and its output end is connected with the clock interface of the subscriber identification card, and sends the subscriber identification card clock signal;

The input end of the reset switching control circuit is connected with the reset interface of the baseband chip, receives the baseband reset signal and the non-contact reset signal, and its output end is connected with the reset interface of the user identification card, and sends the user identification card reset signal;

The baseband monitoring circuit is respectively connected with the clock interface, the reset interface and the data interface of the baseband chip through signal lines, and can monitor the above-mentioned three signals separately or simultaneously, and generates a judgment signal of the ISO7816 interface state of the baseband chip;

The card simulation mode control circuit is respectively connected to the control interface of the clock switching control circuit and the control interface of the reset switching control circuit through signal lines to generate control signals;

The subscriber identification card interface circuit is connected to the second data interface of the subscriber identification card through a signal line to transmit data signals.

The connection device between the above-mentioned dual data interface subscriber identification card and the non-contact front-end chip, wherein the power module includes a subscriber identification card type detection circuit and a subscriber identification card power output circuit including a switch;

The input terminal of the subscriber identification card type detection circuit is connected to the power interface of the baseband chip, and its output terminal is connected to the output selection control terminal of the subscriber identification card power output circuit;

The switch of the power output circuit of the subscriber identification card is connected to the power interface of the baseband chip, and its output selection control terminal is connected to the power interface of the subscriber identification card.

Compared with the prior art, the connection device between the dual data interface user identification card and the non-contact front-end chip of the utility model has the following advantages and positive effects:

1. Since the second data interface added by the subscriber identity card is defined as half-duplex communication, the subscriber identity card does not need to add a more complicated modulation and demodulation circuit, the device is simple to implement, the software is simple to implement, and the cost is also reduced;

2. Subscriber identification cards on some markets already have additional data interfaces. Selecting such chips can only support the non-contact application connection device proposed by the present invention through software upgrades, thereby facilitating the overall promotion of mobile non-contact applications;

3. The second data interface added by the subscriber identification card is a pure digital data interface with high noise tolerance and stable and reliable communication.

Description of drawings

Fig. 1 is the block diagram of the near field communication NFC terminal connection device of prior art;

Fig. 2 is a block diagram of the dual data interface subscriber identification card and the non-contact front-end chip connection device of the present invention;

Fig. 3 is a schematic diagram of the dual data interface subscriber identification card and the non-contact front-end chip connection device of the present invention;

Detailed ways

Further illustrate a kind of preferred embodiment of the present utility model according to Fig. 2 and Fig. 3 below:

As shown in Figure 2, the connection device between the dual data interface subscriber identification card and the contactless front-end chip includes a baseband chip 1, a subscriber identification card 2 and a contactless front-end chip 3; in this embodiment, the baseband chip 1 is produced by Infineon The E-GOLD PMB7880 baseband chip, the subscriber identification card 2 is a NC128 subscriber identification card developed by Microchip, and the non-contact front-end chip 3 is a non-contact front-end chip with a dual data line protocol DWP interface developed by Shanghai Fudan Microelectronics Co., Ltd. Contact the front-end chip FM1920.

The baseband chip 1 includes a power interface 101 , a reset interface 102 , a clock interface 103 , a ground interface 105 and a data interface 107 , and these five interfaces all conform to the ISO7816 standard.

The subscriber identification card 2 includes a power interface 201, a reset interface 202, a clock interface 203, a first reserved interface 204, a ground interface 205, a data interface 207, a second reserved interface 208 and a dual data wire protocol DWP conforming to the ISO7816 standard. The second data interface 206 . (according to the TS 102 600 standard, the first reserved interface 204 and the second reserved interface 208 are defined as the VP and VM signal ends of the subscriber identity card high-speed interface USB.)

Both the data interface 207 and the second data interface 206 are pure digital data interfaces, which are defined as half-duplex communication, and have the same function indicators.

All interfaces of the subscriber identification card 2 follow the ISO/IEC 7816 and TS 102 221 standards, and do not conflict with the pin provisions of the TS 102 600 specification.

The data interface 207 of the subscriber identification card 2 is connected to the data interface 107 of the baseband chip 1 to transmit data signals.

The non-contact front-end chip 3 includes a main control circuit 31 , a control module 32 and a power module 33 .

As shown in FIG. 3 , the main control circuit 31 is respectively connected to the control module 32 and the power module 33 through a bus.

The control module includes a clock switching control circuit 321 , a reset switching control circuit 322 , a baseband monitoring circuit 323 , a card simulation mode control circuit 324 and a user identification card interface circuit 325 .

The clock switching control circuit 321 is realized by a 2-to-1 logic circuit, which is represented by a standard 2-to-1 circuit symbol in FIG. 3 . In the 2-to-1 symbol, two horizontal signals represent signals to be selected, and one vertical signal represents a selection control signal: the L interface at the input end of the clock switching control circuit 321 is connected to the clock interface 103 of the baseband chip 1 to receive the clock input from the baseband chip 1 Signal (the first road horizontal signal); the 1 interface of the clock switching control circuit 321 input terminal is connected with the clock circuit (not shown in the figure) of the non-contact front-end chip 3, and receives the non-contact front-end clock signal (the second road horizontal signal); the clock The output terminal of the switching control circuit 321 is connected with the clock interface 203 of the subscriber identification card 2, and sends to the clock signal of the subscriber identification card 2; the control interface M of the clock switching control circuit 321 is connected with the card simulation mode control circuit 324, and receives the card simulation mode control The clock control signal (vertical signal) generated by the circuit 324.

The reset switching control circuit 322 is also realized by a 2-to-1 logic circuit. The R interface of the reset switching control circuit 322 input terminal is connected with the reset interface 102 of the baseband chip 1, and receives the baseband reset signal (the first road level signal); the r interface of the reset switching control circuit 322 input terminal is connected with the reset circuit of the non-contact front-end chip 3 ( Not shown in the figure) connection, receive the non-contact front-end reset signal (the second road level signal); reset switch control circuit 322 output end is connected with the reset interface 202 of user identification card 2, send to user identification card 2 reset signal; reset switch The control interface m of the control circuit 322 is connected to the card simulation mode control circuit 324 and receives the reset control signal (vertical signal) generated by the card simulation mode control circuit 324 .

In this embodiment, the clock switching control circuit 321 and the reset switching control circuit 322 are realized by AND or NOR logic gates; the clock switching control circuit 321 and the reset switching control circuit 322 can also be realized by MOS or CMOS transmission gates.

The baseband monitoring circuit 323 is connected with the clock interface 103, the reset interface 102, and the data interface 107 of the baseband chip 1 respectively, and generates the baseband chip 1ISO7816 interface state judgment signal according to the signal state of the above-mentioned interface; the baseband monitoring circuit 323 can only monitor the baseband chip 1 clock interface 103 to judge whether the ISO7816 interface of the baseband chip 1 is in a working state or a dormant state, and can also judge the state of the baseband chip 1ISO7816 interface by monitoring the combination of the clock interface 103, reset interface 102 and data interface 107 of the baseband chip 1, and It can record the communication protocol parameters transmitted between the baseband chip 1 and the SIM card 2 during the reset response process, so as to notify the main control circuit 31 of the non-contact front-end chip 3 to communicate with the SIM card 2 with appropriate parameter types.

The subscriber identification card interface circuit 325 is connected to the second data interface 206 of the subscriber identification card 2, and transmits the input/output signal of the subscriber identification card dual data line protocol.

In the normal working mode (referring to the normal working mode in which the terminal is turned on), the card simulation mode control circuit 324 outputs a clock control signal (clock switching control signal), and controls the clock switching control circuit 321 to select the baseband clock signal output to keep the baseband chip 1 It is in a straight-through state with the subscriber identification card 2; when a non-contact application occurs, the baseband monitoring circuit 323 judges whether the baseband chip 1 communicates normally with the subscriber identification card 2, and if the baseband chip 1 is communicating, the card simulation mode control circuit 324 controls the signal to keep selecting The baseband clock signal is output to the subscriber identification card 2, otherwise the clock signal output of the non-contact front end is switched. In order to maintain normal communication between the baseband chip 1 and the SIM card 2, the baseband clock signal has a higher priority than the non-contact front-end clock signal. As long as the clock signal of the baseband chip 1 has a signal, the card emulation mode control circuit 324 preferentially selects the baseband clock signal.

In the power-down mode (the terminal is shut down but requires still supporting the working mode of contactless application), the baseband chip 1 does not work at this time, and the card simulation mode control circuit 324 will switch to the communication between the subscriber identification card 2 and the contactless front-end chip 3, and transmit Contactless front-end clock signal.

The subscriber identification card reset signal is valid during the power-on process and abnormal conditions. Since the interface of the subscriber identification card 2 is connected with the non-contact front-end chip 3, the power-on of the subscriber identification card 2 is controlled by the non-contact front-end chip 3. , so during the power-on process of the non-contact front-end chip 3, the reset signal of the subscriber identification card 2 is controlled by the non-contact front-end chip 3, and after power-on is completed, the reset signal and the clock signal can be processed in the same way. In order to keep the SIM card 2 from the non-contact application mode to the baseband communication mode, the internal state of the SIM card 2 remains unchanged. When no abnormal operation occurs, the SIM card reset signal under the non-contact application can remain inactive.

The user identification card interface circuit 325 is responsible for contactless application communication with the user identification card 2, and the workflow is briefly described as follows: After power-on, the non-contact front-end chip 3 defaults to the user identification card interface circuit 325. The user identification card double data line protocol input The /output signal is in the pull-up state, and the user identification card 2 sets the input/output signal of the dual data line protocol of the user identification card to the input state; during the power-on process, the dual data line protocol of the user identification card is not activated, and the non-contact front-end chip 3 requires the baseband The chip 1 completes the power-on process before communicating with the SIM card 2, and keeps the power supply, clock and reset signals in a straight-through state; when the non-contact front-end chip 3 detects that the SIM card 2 enters an idle state, it starts the dual data line of the SIM card once. Protocol communication, the SIM card interface circuit 325 sends an initialization command to the SIM card 2 through the SIM dual data line protocol input/output signal, and judges whether the SIM card 2 supports the SIM dual data line according to the response of the SIM card 2 If the protocol is supported, corresponding parameters are established; after the non-contact application process is completed, the SIM interface circuit 325 sends an exit command to the SIM card 2 through the SIM dual data line protocol input/output signal to exit. The establishment process of the above-mentioned dual data line protocol can also be carried out without waiting for the SIM card 2 to enter the idle state, and the main control microprocessor CPU of the SIM card 2 is required to have good multi-tasking processing capability.

The power module 33 includes a user identification card type detection circuit 331 and a user identification card power output circuit 332 with three switches. The subscriber identification card power output circuit 332 can optionally include two switches, three switches or multiple switches according to the actual situation. In this embodiment, the subscriber identification card power output circuit 332 includes three switches. The input terminal of the subscriber identification card type detection circuit 331 is connected with the power interface 101 of the baseband chip 1, and its output terminal is connected with the three-way switch output selection control terminal of the subscriber identification card power supply output circuit 332; The first switch s of the power supply output circuit 332 is connected to the power supply interface 107 of the baseband chip 1, and its output terminal is connected to the power supply interface 201 of the subscriber identification card 2. The subscriber identification card power supply output circuit 332 also includes a class B card power supply circuit and its switch b, type C card power supply circuit and its switch c, the type B card power supply circuit and the type C card power supply circuit are used to generate 3v and 1.8v voltage respectively.

According to the standard of subscriber identification card 2, subscriber identification card card type is divided into A, B, C three kinds (A class corresponds to 5V power supply, B class corresponds to 3V power supply, and C class corresponds to 1.8V power supply). The power supply switching of the two types of cards of the C type is taken as an example, and the working process of the power module is explained in detail: in the normal working mode, the power interface 101 of the baseband chip 1 outputs a power supply voltage signal, and the user identification card type detection circuit 331 directly generates three switch control signals , choose to turn on the first switch s, the detection process of the card type is directly carried out by the baseband chip 1 and the subscriber identification card 2, that is to say, the operating voltage of the subscriber identification card 2 is determined by the baseband chip 1 in the normal working mode; At the same time, the subscriber identification card type detection circuit 331 cooperates with the baseband monitoring circuit 323 to record the finally determined type of the subscriber identification card 2 for the application of the power-down mode. In the power-down mode, the baseband chip 1 is no longer working. At this time, the subscriber identification card power supply output circuit 332 is under the control of the main control circuit 31. When switch b is turned on, a 3V power supply is output, or switch c of the power supply circuit of the Class C card is selected to be turned on, and a 1.8V power supply is output. Other power supply types can be expanded with reference to the method of this embodiment.

In this embodiment, the CPU of the SIM card 2 has multi-tasking processing capability, and can simultaneously process the data of the dual data line protocol interface and the 7816 interface of the SIM card.

Described main control circuit 31 is microprocessor, and embedded microprocessor has many choices, and what select for use in the present embodiment is Turbo 8051 microprocessor core.

The baseband chip 1 , the subscriber identification card 2 and the non-contact front-end chip 3 share a common ground.

The connection device of the utility model with double data interface user identification card and non-contact front-end chip is simple to implement, the range of supported user identification cards is expanded, the technical cost is reduced, and it is beneficial to the overall promotion of mobile non-contact applications; at the same time, the noise tolerance of the device Significantly improved, the communication is stable and reliable.

Claims (4)

1. A connection device for a double data interface subscriber identification card and a non-contact front-end chip, comprising a baseband chip, a subscriber identification card connected with the baseband chip in an ISO7816 interface mode and being connected with the baseband chip and the subscriber identification card respectively by an ISO7816 interface The non-contact front-end chip, the baseband chip and the subscriber identification card include a power interface, a reset interface, a clock interface, a ground interface and a data interface, and it is characterized in that: a second data interface is added to the subscriber identification card; The non-contact front-end chip includes a main control circuit, a control module and a power module; The main control circuit is respectively connected to the control module and the power module through a bus; The input terminal of the control module is respectively connected with the reset interface, the clock interface and the data interface of the baseband chip through the signal line, and its output terminal is respectively connected with the reset interface, the clock interface and the second data interface of the subscriber identification card through the signal line. interface connection; The input end of the power module is connected to the power interface of the baseband chip through a power line, and the output end is connected to the power interface of the subscriber identification card through a power line. 2. The connecting device of double data interface subscriber identification card and non-contact front-end chip as claimed in claim 1, it is characterized in that: the data interface of described subscriber identification card and the second data interface are pure digital data interface, are semi-double communication. 3. The connecting device of double data interface subscriber identification card and non-contact front-end chip as claimed in claim 1, it is characterized in that: described control module comprises clock switching control circuit, reset switching control circuit, baseband monitoring circuit, card emulation mode Control circuit and user identification card interface circuit; The input end of the clock switching control circuit is connected with the clock interface of the baseband chip, receives the baseband clock signal and the contactless clock signal, and its output end is connected with the clock interface of the subscriber identification card, and sends the clock signal to the subscriber identification card; The input end of the reset switching control circuit is connected with the reset interface of the baseband chip, receives the baseband reset signal and the non-contact reset signal, and its output end is connected with the reset interface of the user identification card, and sends the reset signal to the user identification card; The baseband monitoring circuit is respectively connected with the clock interface, the reset interface and the data interface of the baseband chip through a signal line, and the circuit can monitor the above-mentioned three signals separately or simultaneously to generate a judgment signal of the ISO7816 interface state of the baseband chip; The card simulation mode control circuit is respectively connected to the control interface of the clock switching control circuit and the control interface of the reset switching control circuit through signal lines to generate control signals; The subscriber identification card interface circuit is connected to the second data interface of the subscriber identification card through a signal line to transmit data signals. 4. The connecting device of double data interface subscriber identification card and non-contact front-end chip as claimed in claim 1, it is characterized in that: described power supply module comprises subscriber identification card type detection circuit and the subscriber identification card power supply output circuit that contains switch; The input terminal of the subscriber identification card type detection circuit is connected to the power interface of the baseband chip, and its output terminal is connected to the output selection control terminal of the subscriber identification card power output circuit; The switch of the power output circuit of the subscriber identification card is connected to the power interface of the baseband chip, and its output selection control terminal is connected to the power interface of the subscriber identification card.

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