WO2020048276A1 - Procédé de protection d'interface de charge et dispositif chargeur - Google Patents

Procédé de protection d'interface de charge et dispositif chargeur Download PDF

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Publication number
WO2020048276A1
WO2020048276A1 PCT/CN2019/099320 CN2019099320W WO2020048276A1 WO 2020048276 A1 WO2020048276 A1 WO 2020048276A1 CN 2019099320 W CN2019099320 W CN 2019099320W WO 2020048276 A1 WO2020048276 A1 WO 2020048276A1
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WIPO (PCT)
Prior art keywords
voltage
pin
charging interface
circuit
control signal
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Application number
PCT/CN2019/099320
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English (en)
Chinese (zh)
Inventor
曾海军
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中兴通讯股份有限公司
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Publication of WO2020048276A1 publication Critical patent/WO2020048276A1/fr

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Definitions

  • the present application relates to circuit protection technology, and in particular, to a protection method and a charging device for a charging interface.
  • USB Universal Serial Bus
  • TPYE C TPYE C interfaces
  • signal pins on the periphery of the charging pin (VBUS / VCHG pin). After the mobile terminal is used for a period of time, the interface will enter the dust phenomenon, or even Water ingress is likely to cause a short circuit or short circuit between VBUS / VCHG pin and the adjacent signal pin.
  • the user when it inserts the data cable, it may cause a short circuit between the VBUS / VCHG pin and the adjacent signal pin, causing some functions to fail, or even the mobile terminal being unusable, causing dissatisfaction or complaints from the mobile terminal user.
  • This situation The TPYE C interface is more obvious, because the TPYE C interface has more pins, and the distance between the pins is smaller. Compared to the conventional USB interface, the above situation is more likely to occur.
  • the embodiments of the present application provide a protection method and a charging device for a charging interface.
  • the method for protecting a charging interface includes: comparing a voltage of a first pin of the charging interface with a reference voltage, and obtaining a first control signal based on a comparison result; and controlling the first control signal based on the first control signal. Whether the second pin of the charging interface is connected to ground.
  • the charging device provided in the embodiment of the present application includes: a charging interface; a comparison circuit for comparing a voltage of a first pin of the charging interface with a reference voltage, and outputting a first control signal based on a comparison result; The first control signal controls whether the second pin of the charging interface is connected to ground.
  • FIG. 1 is a first flowchart of a method for protecting a charging interface according to an embodiment of the present application
  • FIG. 2 is a schematic diagram of a comparator provided in an embodiment of the present application.
  • FIG. 3 is an output diagram of a working principle of a comparator provided in an embodiment of the present application.
  • FIG. 4 is a connection structure diagram of a single comparator and a charging interface according to an embodiment of the present application
  • FIG. 5 is a connection structure diagram of a multi-channel comparator, a charging interface, and a transistor provided in an embodiment of the present application;
  • FIG. 6 is a schematic diagram of a voltage dividing circuit according to an embodiment of the present application.
  • FIG. 7 is a schematic diagram of an output of a voltage divider circuit as an input of a comparator according to an embodiment of the present application
  • FIG. 8 is a second flowchart of a method for protecting a charging interface according to an embodiment of the present application.
  • FIG. 9 is a schematic structural diagram of a charging device according to an embodiment of the present application.
  • the order of the pins of the USB interface is VBUS / VCHG, D- / DM, D + / DP, ID, and GND.
  • the order of the pins of the simple TPYE C interface is GND, VBUS / VCHG, CC2, NC, D + / DP, D- / DM, D + / DP, D- / DM, CC1, NC, VBUS / VCHG, GND.
  • the pins of the TPYE C interface include two rows.
  • the order of the pins on the upper row is GND, TX1 +, TX-, VBUS / VCHG, CC1, D +, D-, SBU1, VBUS / VCHG, RX2-, RX2 +, GND.
  • the order of the pins is GND, RX1 +, RX1-, VBUS / VCHG, SBU2, D-, D +, CC2, VBUS / VCHG, TX2-, TX2 +, GND.
  • the second pin refers to a VBUS / VCHG pin, and is referred to as a charging pin.
  • the first pin refers to the signal pin around the VBUS / VCHG pin.
  • the first pin can be D- / DM, D + / DP, etc.
  • the first pin can be CC2, NC, D + / DP, D- / DM, etc.
  • the first pin can be TX1 +, TX-, RX2-, RX2 +, and so on. It is worth noting that the first pin is not limited to the above example, and any pin that is prone to short circuit with the VBUS / VCHG pin can be used as the first pin.
  • the embodiments of the present application propose the following technical solutions.
  • the voltage of the first pin of the charging interface and the reference voltage are compared, and a first control signal is output based on the comparison result; based on the first control signal, the second control signal of the charging interface is controlled. Whether the pin is connected to ground.
  • the voltage of the first pin will be higher than the reference voltage, thereby triggering the first control signal to achieve the second pin and The ground is connected, and the second pin is a charging pin (VBUS / VCHG pin).
  • the solution of this embodiment adopts a pure hardware circuit to respond more quickly, thereby achieving faster protection of the charging interface, and also protecting the charging interface.
  • Related charging circuit if a short circuit occurs between the second pin and the surrounding first pin, the voltage of the first pin will be higher than the reference voltage, thereby triggering the first control signal to achieve the second pin and The ground is connected, and the second pin is a charging pin (VBUS / VCHG pin).
  • FIG. 1 is a first flowchart of a method for protecting a charging interface according to an embodiment of the present application. As shown in FIG. 1, the method for protecting a charging interface includes the following steps:
  • Step 101 Compare the voltage of the first pin of the charging interface with the reference voltage, and obtain a first control signal based on the comparison result.
  • the voltage of the first pin of the charging interface and the reference voltage may be compared by a comparison circuit (also referred to as a comparator), and the voltage of the first pin of the charging interface may also be compared by a detection circuit. With the size of the reference voltage.
  • the charging interface includes N first pins, where N is a positive integer. All N first pins of the charging interface are connected to a first input terminal of a comparison circuit, the reference voltage is connected to a second input terminal of the comparison circuit, and the N The voltage of the first pin and the reference voltage are compared respectively.
  • N 1, connect a first pin to the first input terminal of the comparison circuit, connect the reference voltage to the second input terminal of the comparison circuit, and compare the The voltage of one first pin is compared with the reference voltage.
  • the comparison circuit can be implemented by a single comparator.
  • N 4, connect 4 first pins to the first input terminal of the comparison circuit, connect the reference voltage to the second input terminal of the comparison circuit, The voltages of the four first pins are compared with the reference voltage, respectively.
  • the comparison circuit can be implemented by a 4-way comparator.
  • the output terminal of the comparison circuit if the voltage of at least one of the N first pins is higher than the reference voltage, the output terminal of the comparison circuit outputs the first voltage; if the N If the voltage of the first pin is lower than the reference voltage, the output terminal of the comparison circuit outputs a second voltage; wherein the first voltage is higher than the second voltage.
  • FIG. 2 is a schematic diagram of a comparator provided in an embodiment of the present application.
  • the comparator may be a single-channel comparator or a multi-channel comparator.
  • the high level of the comparator is defined as V +
  • the low level is defined as V-
  • the first input terminal (that is, the positive input terminal) of the comparator is defined as Vin +
  • the second input terminal (that is, the negative input terminal) is defined Is Vin-
  • the output is defined as Vout.
  • FIG. 3 is an output diagram of the working principle of the comparator provided in the embodiment of the present application, wherein the horizontal axis is the first input terminal (ie, the positive input terminal) Vin + of the comparator, and the vertical axis is the output of the comparator
  • the terminals Vout, V + and V- are the high and low levels of the comparator.
  • V- is 0 in Figure 3.
  • a non-inverting comparator is used.
  • Vin- is the reference voltage.
  • Vin + is greater than Vin-
  • the output terminal Vout becomes High.
  • FIG. 4 is a connection structure diagram of a single comparator and a charging interface according to an embodiment of the present application, where V + of the comparator is connected to VBUS, and V- is grounded; Vin- of the comparator is connected to a VBAT voltage signal or VBUS.
  • the voltage divider circuit, Vin + of the comparator is connected to a signal adjacent to VBUS / VCHG.
  • Figure 4 is signal A; the output of this comparator is used as the input signal of the control terminal (ie, the base) of the triode.
  • Step 102 Control whether the second pin of the charging interface is connected to ground based on the first control signal.
  • an output terminal of the comparison circuit is connected to a control terminal of a switching circuit, and the conducting state of the switching circuit is controlled by the first control signal; wherein, if the first control signal has a first A voltage, the switch circuit is in an on state, and the second pin of the charging interface is connected to ground; if the first control signal has a second voltage, the switch circuit is in an off state, the The second pin of the charging interface is not connected to ground; wherein the first voltage is higher than the second voltage.
  • the switching circuit is a triode or a field effect MOS transistor.
  • FIG. 5 is a connection structure diagram of a multi-channel comparator, a charging interface, and a transistor provided in an embodiment of the present application, where A is a charging interface (also called a connector), and the type of the charging interface is not limited. It is a SUB interface, it can also be a TYPE interface, or a non-standard interface. B is a comparator and C is a transistor. Figure 5 uses the TYPE interface as an example. The number of the second pins is two, which correspond to VBUS in the upper row and VBUS in the lower row, respectively. The first pins near the upper row of VBUS include signal A and signal B. The first pins near the lower row of VBUS include signal C and signal D.
  • A is a charging interface (also called a connector), and the type of the charging interface is not limited. It is a SUB interface, it can also be a TYPE interface, or a non-standard interface.
  • B is a comparator and C is a transistor.
  • Figure 5
  • the output of the comparator is low and the transistor is cut off.
  • the input of Vin + of the comparator The voltage becomes VBUS voltage, and the VBUS voltage is greater than the Vin- voltage.
  • the output of the above comparator becomes high level, so as to control the transistor to turn on and turn off the charging to protect the charging interface and the corresponding circuit on the circuit board (including IC) purpose.
  • the pins of the above row are taken as an example, the pins of the lower row are the same as those of the upper row.
  • the reference voltage is less than the voltage of the second pin.
  • the reference voltage may be a VBAT voltage or a divided voltage of a VBUS voltage.
  • FIG. 6 is a schematic diagram of a voltage dividing circuit provided in an embodiment of the present application, where the VBUS voltage is grounded through two resistors R1 and R2, Vr is output to the input terminal Vin- of the comparator (refer to Figure 7).
  • R1 and R2 are K-level. The specific value can be adjusted according to the voltage of VBUs.
  • This embodiment breaks the original conventional design scheme, and connects the signal pin adjacent to VBUS / VCHG pin at the USB connector or TPYE C connector or other connector to the voltage comparator, and at the same time, one of the VBUS / A transistor is added between VCHG pin and GND.
  • the output of the voltage comparator is used to control the on and off of this transistor, so as to quickly turn off the charging to protect the USB connector, TPYE connector or other connectors and the circuit board.
  • Related circuits finally achieve the purpose of protecting mobile terminal equipment.
  • FIG. 8 is a second flowchart of a method for protecting a charging interface according to an embodiment of the present application.
  • the method of the embodiment of the present application is applied to a charging interface (also referred to as a connector), such as a USB interface, a TPYE interface, etc.
  • the protection method of the charging interface includes the following steps:
  • Step 801 Connect the signal pin of the charging interface adjacent to the VBUS / VCHG pin.
  • Step 802 Select an appropriate voltage comparator according to the number of signal pins adjacent to VBUS / VCHG pin.
  • the voltage comparator may be a single voltage comparator or a multi-channel voltage comparator.
  • V + of the voltage comparator is connected to VBUS and V- is grounded.
  • Step 803 The pin signal received in step 801 is correspondingly connected to Vin + of a single or multiple voltage comparator.
  • Step 804 Connect the divided voltage of Vbat or VBUS to the input Vin- of the single or multiple voltage comparators.
  • Step 805 Select a suitable transistor, and connect the comparator output to the control terminal (base) of the transistor.
  • an NPN type transistor can be selected.
  • Step 806 Connect the VBUS / VCHG pin on the charging interface to the collector terminal of the triode, and the emitter of the triode is grounded.
  • Step 807 Use the base of the triode to control the collector and the emitter to be turned off or on, so as to protect the charging interface and its internal circuit.
  • the following describes the protection process of the charging interface in the embodiment of the present application with two scenarios where a short circuit occurs in the charging interface and the mobile phone battery runs out of power.
  • Scenario 1 Water inlet causes a short circuit in the charging interface. Refer to Figure 2 to Figure 5.
  • the short circuit of water inlet is that signal A and VBUS are shorted.
  • the voltage of signal A will become the voltage of VBUS (the voltage of VBUS is 5V as an example)
  • the input voltage of Vin + of the comparator is 5V
  • the input voltage of Vin- is Vbat voltage or the divided voltage of VBUS.
  • This voltage is less than the voltage of Vin +, so the Vout of the comparator will change from low level to High level, to control the base of the transistor to go high, make its collector and emitter conductive, VBUS and GND short-circuited, so that short-circuit protection is started, charging is stopped, and the purpose of protecting its charging interface and its internal circuit is achieved.
  • Scenario 2 The battery is dead (in this case, the complete dead battery is 0V). At this time, the Vin- of the comparator can only use the VBUS voltage division shown in Figure 6 and Figure 7. At this time, the charger is inserted and the Vin- The input voltage will become the divided voltage of VBUS (such as 4V), the Vout of the comparator is low, and the circuit does not work, which is equivalent to the working scenario with battery power.
  • the above scenario 1 is similar.
  • Scenario 3 The shutdown circuit of the mobile phone does not work. Only when the charger is detected, the circuit starts to work. If no short circuit occurs, the comparator Vin + is greater than Vin-, and the output of the comparator is always low. When a short circuit occurs At this time, the work flow is the same as scenario 1, which is not repeated here.
  • FIG. 9 is a schematic structural composition diagram of a charging device according to an embodiment of the present application.
  • the charging device includes a charging interface 900 and a comparison circuit 901 for comparing a voltage of a first pin 9001 of the charging interface 900. And a reference voltage that outputs a first control signal based on a comparison result; a switching circuit 902 is configured to control whether the second pin 9002 of the charging interface 900 is connected to ground based on the first control signal.
  • the charging interface 900 includes N first pins 9001, where N is a positive integer; all N first pins 9001 of the charging interface 900 are connected to the first input terminal of the comparison circuit.
  • the reference voltage is connected to a second input terminal of the comparison circuit, and the comparison circuit is configured to compare the voltages of the N first pins 9001 and the reference voltage respectively.
  • the output terminal of the comparison circuit 901 if the voltage of at least one first pin 9001 among the N first pins 9001 is higher than the reference voltage, the output terminal of the comparison circuit 901 outputs the first voltage; If the voltages of the N first pins 9001 are lower than the reference voltage, the output terminal of the comparison circuit 901 outputs a second voltage; wherein the first voltage is higher than the second voltage.
  • an output terminal of the comparison circuit 901 is connected to a control terminal of the switch circuit, and the conduction state of the switch circuit is controlled by the first control signal; wherein, if the first control signal With a first voltage, the switch circuit 902 is in a conducting state, and the second pin 9002 of the charging interface 900 is connected to ground; if the first control signal has a second voltage, the switch circuit 902 In the off state, the second pin 9002 of the charging interface 900 is not connected to the ground; wherein the first voltage is higher than the second voltage.
  • the switching circuit 902 is a transistor or a MOS transistor.
  • the reference voltage is less than the voltage of the second pin 9002.
  • the device further includes: a voltage dividing circuit 903; a voltage of the second pin 9002 is connected to an input terminal of the voltage dividing circuit 903, and an output voltage of the voltage dividing circuit 903 is used as the voltage Reference voltage.
  • the first pin 9001 is a signal pin
  • the second pin 9002 is a charging pin
  • the charging interface, the comparison circuit, the switching circuit, and the voltage dividing circuit in the charging device according to the embodiment of the present application can be understood with reference to the specific circuit structures shown in FIG. 2 to FIG. 7, and are not repeated here.
  • the functions implemented by the charging device shown in FIG. 9 can be understood with reference to the related description of the protection method of the charging interface.
  • the technical solution of the embodiment of the present application is used to prevent micro-short circuit, short circuit caused by mobile terminal dust and water, and plugging or unplugging the charging interface or other types of charging terminals by the end user to short-circuit the VBUS / VCHG pin to the adjacent signal pin.
  • the charging interface and related circuits on the circuit board are burned out, which protects the mobile terminal and improves the satisfaction of the end user.
  • the disclosed method and smart device may be implemented in other ways.
  • the device embodiments described above are only schematic.
  • the division of the unit is only a logical function division.
  • there may be another division manner such as multiple units or components may be combined, or Can be integrated into another system, or some features can be ignored or not implemented.
  • the displayed or discussed components are coupled, or directly coupled, or communicated with each other through some interfaces.
  • the indirect coupling or communication connection of the device or unit may be electrical, mechanical, or other forms. of.
  • the units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, which may be located in one place or distributed to multiple network units; Some or all of the units may be selected according to actual needs to achieve the objective of the solution of this embodiment.
  • each functional unit in each embodiment of the present application may be integrated into a second processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into a unit;
  • the above integrated unit may be implemented in the form of hardware, or in the form of hardware plus software functional units.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)
  • Protection Of Static Devices (AREA)

Abstract

La présente invention concerne un procédé de protection d'interface de charge et un dispositif chargeur, le procédé consistant : à comparer une tension d'une première broche d'une interface de charge à une tension de référence, et à obtenir un premier signal de contrôle sur la base d'un résultat de comparaison (101) ; et à contrôler, sur la base du premier signal de contrôle, si une deuxième broche de l'interface de charge est connectée à la masse ou non.
PCT/CN2019/099320 2018-09-04 2019-08-05 Procédé de protection d'interface de charge et dispositif chargeur WO2020048276A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201811028330.6 2018-09-04
CN201811028330.6A CN110875614A (zh) 2018-09-04 2018-09-04 一种充电接口的保护方法及充电装置

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CN111614138B (zh) * 2020-05-25 2022-02-25 维沃移动通信有限公司 接口保护电路和电子设备

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CN105022468B (zh) * 2014-04-21 2018-06-01 国基电子（上海）有限公司 Usb适配器及usb线
CN104505888B (zh) * 2014-12-24 2016-08-17 广东欧珀移动通信有限公司 一种移动终端及充电装置
CN104467109B (zh) * 2014-12-24 2017-02-01 广东欧珀移动通信有限公司 用于为电子设备供电的方法和电子设备
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CN105071795A (zh) * 2015-08-17 2015-11-18 广东欧珀移动通信有限公司 一种基于usb接口的复用电路
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KR20180033452A (ko) * 2016-08-19 2018-04-03 선전 로욜 테크놀로지스 컴퍼니 리미티드 전력 어댑터, 단말기 장치, 충전 시스템 및 충전 방법
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