CN201210753Y - A data line for connecting a dual-mode mobile terminal to an external device - Google Patents

Abstract

This utility model discloses a data cable for connecting a dual-mode mobile terminal to external devices. One end of the data cable connects to a computer's USB interface, and the other end connects to the dual-mode mobile terminal's MINIUSB interface. A data conversion circuit is connected between the USB interface and the MINIUSB interface to convert the data received by the USB interface into UART data, send the differential signal in the UART data to the MINIUSB interface, and send one module platform identification signal in the UART data to a switching circuit. The switching circuit is used to switch different grounding resistance values of the identification terminal in the MINIUSB interface. This utility model realizes the function of time-division multiplexing communication between a computer's USB port and various communication module platforms of a dual-mode mobile phone, solving the disadvantage of requiring different data cables to be changed for communication between the computer and the various platforms of the dual-mode mobile phone. It can be applied to communication between single-mode and dual-mode mobile phones and computers, improving production efficiency and reducing costs.

Description

A data line for connecting a dual-mode mobile terminal to an external device

technical field

The utility model belongs to the technical field of data communication between different devices, and more specifically relates to a data line connecting a dual-mode mobile terminal and a computer USB port.

Background technique

In the mobile terminal industry, when performing data transmission between computers and mobile terminals, the more commonly used technical method is to communicate between the COM port of the PC, that is, the serial communication port, and the UART port of the mobile terminal, especially in the mobile terminal. In the manufacturing mode, currently the UART port of the mobile terminal is connected to the COM port of the PC for one-to-one data transmission and program download. When using the COM port of the computer, it is necessary to add a circuit to realize the RS_232C logic. Level switching between ports and TTL logic ports.

For the MINI USB interface commonly used by mobile terminals at present, when the PC and the two wireless communication module platforms of the dual-mode mobile terminal switch communication, because there are too few input and output terminals in the MINI USB interface, the ID terminal in the interface is required to identify different One type of data line corresponds to a platform of dual-mode mobile terminals. In this way, many external communication functions of mobile terminals require two types of data lines to be used instead, which reduces the efficiency of communication between devices and reduces the efficiency of computers and computers. The service life of the mobile terminal interface.

Contents of the invention

The purpose of this utility model is to solve the problem of communication between different platforms between the computer and the dual-mode mobile terminal using the MINIUSB interface, overcome the shortcomings of the need to replace the data line between the two platforms of the mobile terminal and the computer interface, and provide a data line Time-division multiplexing of communication between the dual-mode mobile terminal and the computer can be realized conveniently and quickly.

In order to achieve the above object, the utility model proposes a data line for connecting a dual-mode mobile terminal to an external device. One end of the data line is a USB interface connected to a computer, and the other end is a MINIUSB interface connected to a dual-mode mobile terminal. There is a data conversion circuit connected between the interface and the MINIUSB interface, which is used to convert the data received by the USB interface into UART data, and send the differential signal in the UART data to the MINIUSB interface, and convert a module platform identification signal in the UART data to the MINIUSB interface. It is sent to a switch circuit, and the switch circuit is used to switch the different grounding resistance values of the identification terminals in the MINIUSB interface.

Further, the switch circuit is connected between the data conversion circuit and the MINIUSB interface, the control terminal of the switch circuit is connected to a module platform identification signal sent by the data conversion circuit, and the gate terminal of the switch circuit is connected to As for the identification terminal in the MINIUSB interface, the gate terminal is connected to resistors of different values according to the level of the identification signal of the module platform. The module platform identification signal is used to distinguish the CDMA communication module platform and the GSM communication module platform of the dual-mode mobile terminal. The switch circuit is a single pole double throw analog switch.

The technical solution proposed by the utility model also includes the following technical features: the 5V DC power output from the power terminal of the USB interface of the data line is divided into two circuits, one of which is filtered and connected to the data conversion circuit for power supply, and the other Connect all the way to the power terminal of the MINIUSB. The data conversion circuit converts the 5V DC power supply to 3.3V through a step-down regulator, and connects to the UART signal output level reference voltage after passing through a filter circuit connected in parallel with capacitors. The data conversion circuit adopts an integrated chip.

Compared with the prior art, the advantages and positive effects of the utility model are: the data line automatically recognizes the two communication module platforms of the dual-mode mobile terminal through the switching of two kinds of resistance values to the ground of the ID terminal of the MINIUSB interface. One data cable can be widely used in applications such as dual-mode or single-mode mobile terminal software download and after-sales software upgrade using MINIUSB interface. The same port is time-division multiplexed between the two platforms of the dual-mode mobile terminal and the computer for data transmission and communication. Program download. At the same time, due to the use of the computer USB interface which is easy to expand, it can be expanded according to the needs to realize the purpose of simultaneous communication between the computer and multiple mobile terminals.

Description of drawings

Fig. 1 is a circuit principle block diagram of the present utility model;

Fig. 2 is the conversion circuit diagram of USB differential data to UART data in one embodiment of the utility model;

Fig. 3 is a schematic diagram of an analog switch in an embodiment of the present invention;

Fig. 4 is a connection diagram of the analog switch circuit and MINIUSB in one embodiment of the present invention.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

As shown in Figure 1, it is a schematic block diagram of the data line connecting the dual-mode mobile terminal to external devices. Its specific working principle is as follows: one end of the data line is an ordinary USB interface, which is connected to the computer USB interface to realize data communication, and the other end of the data line One end is the MINI USB interface connected to the dual-mode mobile terminal, and the data line USB interface connected to the computer receives the USB differential data output by the computer and 5V DC power supply, and the USB differential data is sent to the data conversion circuit for USB data conversion. It is UART data, the module platform identification signal in the UART data is sent to the analog switch for the switching of the analog switch, and the rest of the data signals are connected to the corresponding pins of MINI USB for communication with the dual-mode mobile terminal. The 5V DC power supply is divided into two circuits, one for powering the USB-to-UART data conversion circuit, and the other for powering the dual-mode mobile terminal connected to the MINI USB interface.

As shown in Figure 2, it is a conversion circuit diagram of USB differential data to UART data, and its specific working principle is as follows: the data conversion circuit of USB to UART uses a data conversion chip U2 to realize the conversion of USB differential data. First, the USB interface JS2 of the data line is connected to the USB interface of the computer, and the D+ and D- terminals in the USB interface receive the differential data output by the computer and the power terminal receives the 5V DC power output from the computer, and the 5V DC power passes through the capacitor C7 of different parameters The parallel circuit composed of , C8 is strictly filtered and divided into two circuits, one of which is a 5V DC power supply that provides working voltage for it through pins 8 and 20 of the data conversion chip U2. The data conversion chip U2 converts the 5V voltage to 3.3V through the internal LDO low-voltage regulator and outputs it through pin 17. At the same time, a parallel circuit composed of capacitors C5 and C6 is used to filter the 3.3V output voltage of the data conversion chip U2.

The D+ and D- terminals of the USB interface of the data line receive the USB differential data from the computer, and the differential data are respectively sent to the 15 and 16 pins of the signal conversion chip U2 through the protection resistors R15 and R16 for conversion, and the D+ signal passes through the resistors R13 is connected to the 3.3V power supply output by the data conversion chip U2, which is used for the computer to identify external devices.

The pins 27 and 28 of the data conversion chip U2 are connected across the crystal oscillator Y1, and grounded through the fine-tuning capacitors C3 and C1 respectively, which can provide an accurate working clock for the data conversion chip U2 and output the level reference voltage of the 4-pin UART of the data conversion chip U2 Connect with 3.3V voltage, so that the TTL level of UART output is 3.3V. Pin 2 of the data conversion chip U2 outputs a module platform identification signal, which is connected to the input terminal of the analog switch U1, thereby controlling the switching of the analog switch U1.

Pins 1, 2, 4, 5, 6, 9, 10, and 11 of the data conversion chip U2 are converted UART signal pins, of which pins 5, 6, 9, 10, and 11 are passed through resistors R10, R5, R8, and R14 respectively. , R9 is pulled up to 3.3V. Resistors R6 and R7 are protection resistors for UART signals. Pins 13 and 14 of the data conversion chip U2 are not used, so they are pulled up to 3.3V through resistors R11 and R12 to prevent interference with its normal work. The data conversion chip U2 inputs the differential signals D+, D- to the corresponding terminals of the MINI USB interface.

In the utility model, the simplest way of the switch circuit is to use a single-pole double-set switch, and it can also be realized by other various structural forms. As shown in Figure 3, the analog switch circuit adopts a two-way single-pole double-set switch. One switch is used to switch the grounding resistance of the ID port of the MINIUSB interface, and the other is used to invert the control signal and output it. Both the first analog switch and the second analog switch have an input terminal IN1 (pin 1) and IN2 (pin 5) for receiving control signals, and the received switch control signal comes from the output of the second pin of the signal conversion chip U2 control signal. According to the level difference of the received switch control signal, the first analog switch switches between the conduction terminal NO1 (pin 2) and NC1 (pin 9), and the common terminal COM1 is pin 10. The second analog switch switches between the conduction terminal NO2 (pin 4) and NC2 (pin 7), and the common terminal COM2 is pin 6.

As shown in Figure 4, it is the connection relationship between the analog switch circuit in the data line, the data conversion circuit and the MINI USB interface. Its specific working principle is as follows: the analog switch chip U1 is a two-way single-pole double-set analog switch, of which 3, Pin 8 is the power supply pin, which is connected to the 3.3V voltage output by the data conversion chip U2, and the capacitor C2 is the decoupling capacitor of the chip U1 to prevent power fluctuation from affecting its normal operation. The analog switch circuit connects the module platform identification signal output by the data conversion chip U2, that is, the CONTROL signal, to the input end (pin 1 of U1) of the first analog switch and the input end (pin 5 of U1) of the second analog switch, That is, use the CONTROL signal to control the first analog switch and the second analog switch to switch simultaneously. When the TTL level of the CONTROL signal is low, the common end of the first analog switch (pin 10 of U1) is connected to the strobe end 9 pin, grounded through the resistor R3, and the common end of the second analog switch (pin 6 of U1 Pin) is connected to pin 7 of the gate terminal, connected to the 3.3V power supply through resistor R1; when the TTL level of the CONTROL signal is high, the common terminal of the first analog switch is connected to pin 2 of the gate terminal, and grounded through resistor R4 , the common terminal of the second analog switch is connected to pin 4 of the gate terminal, and grounded through the resistor R2.

Pin 10 of the common end chip U1 of the first analog switch is also connected to pin 4 of the MINI USB interface JS1. Depending on the level of the identification signal of the module platform, pin 10 of the chip U1 is grounded through different resistors R3 or R4. With different resistance values, MINI USB can identify different module platforms, and the MINI USB interface JS1 is connected to the module platform inside the mobile phone to complete the data transmission function for different module platforms.

When realizing data communication between a computer and a dual-mode mobile terminal, first open the corresponding serial port of the data line on the PC, then configure the communication parameters (baud rate, check bit, etc.), and then control the analog switch by setting the high and low levels of the CONTROL signal , make the 4-pin resistance of JS1 to R3 or R4 to realize communication with communication module platform 1 or communication module platform 2, and close the serial port after the communication is completed. The dual-mode mobile terminal here may be a mobile terminal with CDMA/GSM communication modules, the communication module platform 1 is a CDMA communication module, and the communication module platform 2 is a GSM communication module.

The above embodiment is only a kind of implementation mode of the present utility model, is not the limitation and exhaustive list of the present utility model, and the various changes, remodeling, remodeling, Adding or replacing all belong to the protection scope of the present utility model.

Claims (7)

1. A kind of dual-mode mobile terminal connects the data line of external equipment, and one end of data line is the USB interface that connects computer, and the other end is the MINIUSB interface that connects dual-mode mobile terminal, it is characterized in that described USB interface and MINIUSB interface There is a data conversion circuit connected between them, which is used to convert the data received by the USB interface into UART data, and send the differential signal in the UART data to the MINIUSB interface, and send a module platform identification signal in the UART data to a switch circuit, the switch circuit is used to switch the different grounding resistance values of the identification terminals in the MINIUSB interface. 2. The data line according to claim 1, characterized in that the switch circuit is connected between the data conversion circuit and the MINIUSB interface, and the control terminal of the switch circuit is connected to a module issued by the data conversion circuit For the platform identification signal, the gate end of the switch circuit is connected to the identification terminal in the MINIUSB interface, and the gate end is connected to resistors of different values according to the level of the module platform identification signal. 3. The data line according to claim 2, characterized in that the module platform identification signal is used to distinguish the CDMA communication module platform and the GSM communication module platform of the dual-mode mobile terminal. 4. The data line according to claim 1 or 2, characterized in that said switch circuit is a single pole double throw analog switch. 5. The data line according to claim 1, characterized in that the 5V DC power output from the power terminal of the USB interface of the data line is divided into two paths, one path is filtered and connected to the data conversion circuit for power supply, The other way is connected to the power terminal of the MINIUSB. 6. The data line according to claim 1, wherein the data conversion circuit converts the 5V DC power supply to 3.3V through a step-down regulator, and is connected to the UART after passing through a filter circuit connected in parallel with capacitors Signal output level reference voltage. 7. The data line according to claim 1, characterized in that said data conversion circuit adopts an integrated chip.

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