WO2010048873A1

WO2010048873A1 - Method and device for identifying type of charger

Info

Publication number: WO2010048873A1
Application number: PCT/CN2009/074627
Authority: WO
Inventors: 侯靖波
Original assignee: 华为终端有限公司
Priority date: 2008-10-28
Filing date: 2009-10-27
Publication date: 2010-05-06
Also published as: CN101398459B; CN101398459A

Abstract

A method for identifying the type of a charger and a device thereof are disclosed. In the method, a divider resistance is connected in series between the output terminal of power supply of an electrical equipment and a second pin of a universal serial bus Mini USB-A type interface. The method for identifying the type of the charger includes: the second pin and a third pin of the Mini USB-A type interface are set in a high-impedance state when detecting that the charger is accessed; a measuring point is set between the Mini USB-B type interface of the charger and the divider resistance, and the voltage at the measuring point is measured; the type of the charger is identified according to the measured voltage result.

Description

Instruction manual

Title of Invention: Method and device for identifying charger type

[1] This application claims priority to Chinese Patent Application No. 200810172556.3, entitled "Method and Apparatus for Identifying Charger Types", filed on October 28, 2008, the entire contents of which are incorporated by reference. In this application.

[2] Technical field

[3] The present invention relates to the field of terminal technologies, and in particular, to a method and apparatus for identifying a type of a charger.

[4] Background of the invention

[5] USB (Universal Serial Bus) is an interface technology used in the computer field. It has been widely used in various electronic products such as mobile phones, portable players, and computer peripherals. Since the USB standard can provide 5V, many battery-powered devices can be charged by USB. Most of the charging interfaces are in the form of Mini_USB. Mini_USB is a miniaturized universal serial bus interface that includes both Type A and Type B. The interface on the device is Mini_U SB-A type, which can be connected to the standard USB interface on the computer through a data cable with Mini_USB-B type interface; it can also be connected to a dedicated charger with Mini_USB-B type interface.

[6] Currently, dedicated chargers are divided into standard chargers and non-standard chargers. Standard charger has a large flow capacity

The typical value is 650mA; the non-standard charger has a relatively weak current supply capacity, typically 300mA. When a computer cable is used to connect to a computer, the computer can also be understood as a charger with a maximum supply capacity of 500 mA.

[7] Since the supply capacity of the above three chargers is different, in order to ensure the safety of charging, the charging equipment needs to limit the charging current to the minimum value of the three chargers, for example, below 300 mA. With this method, although the charging safety is guaranteed, when the user uses the standard charger for charging, the charging current is limited, which causes the charging time to become longer and the user feels poor. And the probability that users use standard chargers is the biggest, which is also a resource waste for standard chargers.

[8] If the electrical equipment is limited according to the current supply capacity of the standard charger, for example, limited to 650 mA, it will be marked on the electrical equipment to remind the user not to use other types of charging other than the standard charger. Device. This method poses a greater risk that, if the user mishandles it, it may cause damage to non-standard chargers or even computers.

In summary, in the prior art, there is no method for fully utilizing the power supply capability of various types of chargers while ensuring the safety of charging.

Summary of the invention

In view of this, the embodiments of the present invention provide a method and device for identifying a type of a charger, so that the charging current can be set according to the type of the charger, ensuring the safety of the charging, and fully utilizing the power supply capability of the various chargers. The technical solutions are as follows:

An embodiment of the present invention provides a method for identifying a type of a charger, and a series voltage dividing resistor is connected between a power output end of the power device and a second pin of the Mini Universal USB bus type Mini_USB-A type interface;

The method for identifying a charger type includes:

When the charger is detected, the second pin and the third pin of the Mini_USB-A type interface are set to a high impedance state;

Setting a measurement point between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor, and measuring the voltage of the measuring point;

The type of the connected charger is identified based on the voltage measurement.

An embodiment of the present invention further provides an apparatus for identifying a type of a charger, including:

a resistance state setting unit, configured to set a second bow pin and a third pin of the small universal serial bus Mini_USB-A type interface of the power device to a high impedance state when the charger is detected;

a voltage measuring unit, configured to measure a voltage of the measuring point after the resistance state setting unit completes the resistance state setting; wherein, between the power output end of the power device and the second pin of the Mini_USB-A type interface There is a voltage dividing resistor connected in series, and the measuring point is located between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor.

An identifying unit, configured to identify the type of the connected charger according to the measurement result of the voltage measuring unit

The above technical solution realizes the identification of the type of the connected charger without any modification and limitation of various types of chargers, so that the charging device can set different charging currents according to the type of the connected charger. Compared with the prior art, the application of the above technical solution can ensure the safety of charging , give full play to the supply capacity of various types of chargers, and enhance user experience.

[22] BRIEF DESCRIPTION OF THE DRAWINGS

[23] FIG. 1 is a schematic structural diagram of hardware of a powered device end for implementing an embodiment of the method of the present invention;

2 is a schematic diagram of hardware connection of a computer data cable access port in an embodiment of the present invention;

FIG. 3 is a schematic diagram of hardware connection of a non-standard charger access port according to an embodiment of the present invention; FIG.

FIG. 4 is a schematic diagram of hardware connection of a standard charger access port according to an embodiment of the present invention; FIG.

Figure 5 is a flow chart showing a specific embodiment of the method of the present invention;

6 is a schematic structural diagram of a device for identifying a charger type according to an embodiment of the present invention;

FIG. 7 is a schematic structural diagram of an identification unit according to an embodiment of the present invention; FIG.

[30] FIG. 8 is a schematic structural diagram of a power-consuming device according to an embodiment of the present invention;

FIG. 9 is a schematic structural diagram of the identification unit of FIG. 8 according to an embodiment of the present invention.

[32] Mode for carrying out the invention

[33] The three types of chargers mentioned in the background have Mini_USB-B type interfaces, but each charger has a specific pin (pin) structure inside its interface:

[34] The standard charger shorts Pin2 and Pin3 inside the Mini_USB-B type interface;

[35] The non-standard charger does not short-circuit Pin2 and Pin3 inside the Mini_USB-B type interface;

[36] When using a data cable with a Mini_USB-B type connector to connect to a computer, the computer acts as a charger, and a pull-down resistor is connected in series on Pin2 inside the computer.

[37] The embodiment of the present invention utilizes the inherent characteristics of the three types of chargers to implement the identification of the three types of chargers. First, the method for identifying the type of the charger in the embodiment of the present invention is described:

[38] a series divider resistor is connected between the power output of the powered device and the second pin of the Mini Universal USB Bus Mini_USB-A type interface;

[39] The method for identifying a charger type includes:

[40] When the charger is detected, set the second and third pins of the Mini_USB-A type interface to high impedance;

[41] setting a measurement point between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor, and measuring the voltage of the measuring point;

[42] Identify the type of charger connected based on the voltage measurement. [43] Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[44] The hardware structure diagram of the power device end in the embodiment of the present invention is shown in FIG. 1 , the Mini_US B interface type of the power device end is A type, and the power output end may be a VRIO (Voltage Reglator Input/Output, Input and output voltage regulator), set its output voltage to 11. Between the VRIO and the PinJ2 of the MiniJJSB-A type interface, a resistor R1 and a diode D1 are connected in series. Since there is a pull-down resistor (set to R2) in series on the internal Pin2 of the computer, R1 is used to connect with the computer, and the voltage is connected in series with R2, so that the Mini_USB-B type interface and the sub-located charger are connected. A low level state is present at the measurement point between the voltage resistors R1. Since the resistance of the pull-down resistor R2 is generally a few K, the resistance of R1 can be selected from 100 Κ to 150 Κ. The diode D1 acts as a limiting reflow device and is mainly used to limit the current flow to the power output.

[45] It should be noted that the purpose of setting the above measurement points is to obtain the high/low state of the Mini_USB-B type interface Pin2 of the connected charger, and the buck parameter of the diode does not affect the measurement result. Therefore, in FIG. 1, the test point can also be set at the cathode end of D1; and, in particular, other types of limiting reflow devices other than diodes can also be selected, which do not affect the implementation of the embodiment of the present invention. .

[46] When it is detected that there is a charger connected to the outside, the powered device first sets Pin2 and Pi n3 of the Mini_USB-A type interface to a high impedance state. Therefore, for different types of charger access, the measurement points in Figure 1 will have different states:

[47] 1. As shown in Figure 2, when the computer data cable is connected, the Mini_USB-B connector Pin2 will be short-circuited with the D- pin of the standard USB interface on the computer. There is a pull-down resistor R2, so the resistor R2 in series with Rl, D1 will cause the measurement point to assume a low state.

[48] 2. As shown in Figure 3, when the non-standard charger is connected, since the non-standard charger has no short-circuit between Pin2 and Pin3, and there is no pull-down resistor, the measurement point will be in a high state.

[49] 3. As shown in Figure 4, when the standard charger is connected, since the standard charger internally shorts Pin2 and Pin3, but there is no pull-down resistor, the measurement point will be in a high state.

[50] According to the above three cases, the embodiment of the present invention provides a method for identifying a type of a charger. The flowchart of the method is shown in FIG. 5, and specifically includes:

[51] S501, when it is detected that there is external charger access, set Pin2 and Pin3 of the Mini_USB-A interface to High resistance state.

[52] Pinl in the USB standard can provide 5V voltage, so it can be judged whether there is an external charger by detecting whether there is a supply voltage on the Pinl of the Mini_USB-A type interface.

[53] S502, when it is measured that Pin2 of the Mini_USB-B type interface of the connected charger is low level, it is judged that the connected charger is a computer; if the measurement result is high level, it proceeds to S503.

[54] Here you can use the GPIO (General Purpose Input/Output) or ADC (Analog to Digital Converter) in the powered device to measure the voltage at the measuring point. The high and low states of the point level are measured, and the actual voltage value at the point can be measured by using the ADC, and then it is judged whether it is low level according to the actual voltage value.

[55] If the detection result is low, it can be judged that the type of charger connected is a computer, and the charging current of the consumer can be set according to the power supply capability of the computer, for example, 500 mA.

[56] S503, the data transmitting end sends the test signal; if the data receiving end receives the test signal, it determines that the connected charger is a standard charger, otherwise it determines that the connected charger is a non-standard charger.

[57] According to the USB standard, Pin2 and Pin3 of the Mini_USB interface are used for data transmission/reception. Therefore, the above data transmitting end may be Pin2 or Pin3 of the Mini_USB-A type interface, and the corresponding data receiving end is the Mini_USB-A type interface Pin3 or Pin2.

[58] The powered device configures Pin2 and Pin3 to send a specific test data from the data transmitting end, and then the data receiving end reads the data in the receiving register and compares it with the sent test data. If the two are the same, then It indicates that Pin2 and Pin3 of the Mini_USB-B interface are shorted together, so that it can be judged that the standard charger is connected. This can limit the charging current to the rated current of the standard charger, for example, 6 50mA; The data is different from the data sent, indicating that the Pin2 and Pin3 of the Mini_USB-B interface are not shorted together, so that it can be judged that the non-standard charger is connected, and the charging current can be limited to the rated current of the non-standard charger. , for example 300mA.

[59] If the powered device can provide the data transmission/reception interface as a GPIO function, the identification of the above standard charger and non-standard charger can also be implemented in another way: Mini_USB- The Pin2 and Pin3 interfaces of the Type A interface are configured as GPIO functions and one of the pins is set low. Then measure the voltage of the other pin. If the measurement result is also low, it means that the two pins are shorted together externally, so that it can be judged that the standard charger is connected, otherwise it is non-standard. Charger.

[60] It is easily conceivable by those skilled in the art that for the identification of a standard charger and a non-standard charger, the key is to determine whether Pin2 and Pin3 of the Mini_USB-B type interface of the connected charger are short-circuited, as described above. The two specific implementations are not intended to limit the scope of the present invention.

[61] The above technical solutions, for the general use of the Mini_USB interface charging equipment on the market, without any modification and limitation of various types of chargers, proposed a low cost and high reliability combined with software and hardware. The detection scheme realizes different types of charger identification, and sets different charging currents according to the type of the charger, thereby fully utilizing the power supply capability of various chargers and improving the user experience while ensuring the safety of charging.

[62] It will be understood by those skilled in the art that all or part of the steps of implementing the foregoing method embodiments may be performed by hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Corresponding to the above method embodiment, the embodiment of the present invention further provides an apparatus for identifying a type of a charger, as shown in FIG. 6, including:

[64] The resistance state setting unit 610 is configured to set the second bow pin and the third pin of the small universal serial bus Mini_USB-A type interface of the power device to be high when the charger access port is detected Resistance state

[65] The voltage measuring unit 620 is configured to measure a voltage at a preset measurement point after the resistance state setting unit completes the resistance state setting; wherein, at the power output end of the power device and the Mini_USB-A type Between the second pins of the interface, a voltage dividing resistor is connected in series, and the measuring point is located between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor;

[66] Preferably, between the power output of the powered device and the second pin of the Mini_USB-A type interface, a limiting reflow device is further connected in series for limiting current flow to the power output.

[67] The identification unit 630 is configured to identify the type of the connected charger according to the measurement result of the voltage measuring unit 620.

[68] As shown in FIG. 7, the identification unit 630 includes:

[69] a first identification subunit 631, if the measurement result of the voltage measurement unit 620 is a low level, identifying that the connected charger is a computer; [70] The second identification subunit 632 determines whether the second pin and the third pin of the Mini_USB-B type interface of the connected charger are short if the measurement result 620 of the voltage measuring unit is a high level. If yes, identify the connected charger as a standard charger; if not, identify the connected charger as a non-standard charger.

[71] As shown in FIG. 8, an embodiment of the present invention further provides an electrical device, including:

[72] The resistance state setting unit 810 is configured to set the second bow pin and the third pin of the small universal serial bus Mini_USB-A type interface of the power device to be high when the charger access port is detected Resistance state

[73] The voltage measuring unit 820 is configured to measure a voltage at a preset measurement point after the resistance state setting unit completes the resistance state setting; wherein, the power output end of the power device and the Mini_USB-A type Between the second pins of the interface, a voltage dividing resistor is connected in series, and the measuring point is located between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor;

[74] Preferably, between the power output of the powered device and the second pin of the Mini_USB-A type interface, a limiting reflow device is further connected in series for limiting current flow to the power output.

[75] The identifying unit 830 is configured to identify the type of the connected charger according to the measurement result of the voltage measuring unit 820.

[76] The charging current setting unit 840 is configured to determine, according to the identification unit 830, the type of the connected charger, set the charging current of the powered device, that is, set different charging currents according to the type of the charger. That is, if it is determined by the identification unit that the type of the connected charger is a computer, the charging current of the powered device can be set according to the current supply capability of the computer, for example, 500 mA; if the identification unit can determine that the non-standard charger is accessed This pin can limit the charging current to the rated current of the non-standard charger, for example 300mA.

[77] As shown in FIG. 9, the identification unit 830 includes:

[78] a first identifying subunit 831, if the measurement result of the voltage measuring unit 820 is a low level, identifying that the connected charger is a computer;

[79] The second identification subunit 832 determines whether the second pin and the third pin of the Mini_USB-B type interface of the connected charger are short if the measurement result 820 of the voltage measuring unit is a high level. If yes, identify the connected charger as a standard charger; if not, identify the connected charger as a non-standard charger. [80] For the above embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method embodiment. The embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, ie may be located in one Places, or they can be distributed to multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the embodiment. Those of ordinary skill in the art can understand and implement without any creative effort.

The above description is only the specific embodiment of the present invention, and it should be noted that those skilled in the art can make some improvements and refinements without departing from the principles of the present invention. And retouching should also be regarded as the scope of protection of the present invention.

Claims

Claim

A method for identifying a type of a charger, characterized in that a voltage dividing resistor is connected in series between a power output end of the electric device and a second pin of the mini universal USB bus Mini_USB-A type interface;

The method for identifying a charger type includes:

The method according to claim 1, wherein the power output terminal of the powered device is: an input/output voltage regulator VRIO of the powered device.

The method for identifying a type of a charger according to claim 1, wherein a limit return is further connected in series between a power output of the powered device and a second pin of the Mini-USB-A type interface of the small universal serial bus The device, the limiting reflux device, is configured to limit current flow to the power output.

A method of identifying a type of charger according to claim 3, wherein said restricting reflow device is a diode.

The method for identifying a type of a charger according to claim 1, wherein when the charger is detected, the second pin and the third pin of the Mini_USB-A type interface are set to high impedance. State, the specific implementation is:

When it is detected that there is a supply voltage 第一 on the first pin of the Mini_USB-A type interface, the second bow I and the third pin of the Mini_USB-A type interface are set to a high impedance state.

The method for identifying a type of a charger according to claim 1, wherein the measuring the voltage of the measuring point is specifically implemented as:

The voltage at the measurement point is measured using a general-purpose input/output interface GPIO. A method of identifying a type of charger according to claim 1, wherein said The voltage at the measurement point is measured using an analog to digital converter ADC.

The method for identifying a type of a charger according to any one of claims 1 to 7, wherein the identifying the type of the connected charger according to the voltage measurement result comprises: if the voltage measurement result is a low level, Identifying the connected charger as a computer; if the voltage measurement result is high, it is determined whether the second pin and the third pin of the Mini_USB-B type interface of the connected charger are short-circuited; if yes, The identified charger is identified as a standard charger; if not, the connected charger is identified as a non-standard charger.

The method for identifying a type of a charger according to claim 8, wherein the determining whether the second pin and the third pin of the Mini_USB-B type interface of the connected charger are shorted are specifically implemented as follows:

The test signal is sent by the data transmitting end; if the data receiving end receives the test signal, the second pin of the Mini_USB-B type interface of the charger connected to the battery is short-circuited with the third pin;

The data transmitting end is a second bow I pin or a third pin of the Mini_USB-A type interface, and the data receiving end corresponding thereto is a third pin or a second pin of the Mini_USB-A type interface.

Configure both the data transmitter and the data receiver as the general-purpose input/output interface GPIO function, and set one of the ports to low level; measure the voltage of the other port, if the measurement result is low, the access is The second pin of the Mini_USB-B type connector of the charger is short-circuited with the third pin; if the measurement result is high level, the second bow I and the third of the Mini_USB-B type interface of the connected charger are connected. The pin is not shorted;

The data transmitting end is a second bow pin or a third pin of the Mini_USB-A type interface, and the data receiving end corresponding thereto is a third pin or a second pin of the Mini_USB-A type interface. [Claim 11] The method for identifying a charger type according to claim 1, wherein the method further comprises:

According to the type of charger that is connected, the charging current of the powered device is set.

[Claim 12] A device for identifying a type of charger, comprising:

a resistance state setting unit, configured to set a second bow I and a third pin of the small universal serial bus Mini_USB-A type interface of the power device to a high impedance state when the charger is detected;

a voltage measuring unit, configured to measure a voltage at the measuring point after the resistance state setting unit completes the resistance state setting; wherein, the second pin of the power supply output end of the power device and the Min i_USB-A type interface Between the series, there is a voltage dividing resistor, the measuring point is located between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor; the identifying unit is configured to identify according to the measurement result of the voltage measuring unit The type of charger connected.

[Claim 13] The device for identifying a charger type according to claim 11, wherein the power supply output end of the electric device and the second pin of the Mini_USB-A type interface are further limited in series A reflow device is configured to limit current flow to the power output.

[Claim 14] The device for identifying a charger type according to claim 11, wherein the identification unit comprises:

a first identifying subunit, if the measurement result of the voltage measuring unit is a low level, identifying that the connected charger is a computer;

a second identification subunit, if the measurement result of the voltage measurement unit is a high level, whether the second pin and the third pin of the Mini_USB-B type interface of the charger connected to the charger are short-circuited; , the identified charger is a standard charger; if not, it identifies that the connected charger is a non-standard charger.

[Claim 15] A powered device, comprising:

a resistance state setting unit, configured to set a second bow pin and a third pin of the small universal serial bus Mini_USB-A type interface of the power device to a high impedance state when detecting that the charger is connected; a voltage measuring unit, configured to measure a voltage at the measuring point after the resistance state setting unit completes the resistance state setting; wherein, the second pin of the power supply output end of the power device and the Min i_USB-A type interface Between the series, there is a voltage dividing resistor, the measuring point is located between the Mini_USB-B type interface of the connected charger and the voltage dividing resistor; the identifying unit is configured to identify according to the measurement result of the voltage measuring unit The type of charger connected;

And a charging current setting unit, configured to determine, according to the identifying unit, the type of the connected charger, and set a charging current of the powered device.

[Claim 16] The electric device according to claim 15, wherein the limiting current reflow device is further connected in series between the power output end of the electric device and the second pin of the Mini_USB-A type interface. Used to limit current flow to the power output.

[Claim 17] The electric device according to claim 15, wherein the identification unit comprises: