WO2020253520A1

WO2020253520A1 - Device to be charged and charging method

Info

Publication number: WO2020253520A1
Application number: PCT/CN2020/093984
Authority: WO
Inventors: 刘绍斌; 李家达; 史岩松
Original assignee: Oppo广东移动通信有限公司
Priority date: 2019-06-18
Filing date: 2020-06-02
Publication date: 2020-12-24
Also published as: CN110277814A; CN110277814B

Abstract

Disclosed are a device to be charged and a charging method. Said device comprises: a battery unit, a charging interface, a switch unit, a drive circuit and a control unit. A first end of the switch unit is connected to the battery unit, and a second end thereof is connected to the charging interface; the drive circuit is connected to a third end of the switch unit; and the control unit is connected to the charging interface and is used for detecting, by means of the charging interface, whether there is a power supply providing apparatus that is connected to said device, providing a first drive signal to the drive circuit by means of a first pin when it is detected that there is no power supply providing apparatus that is connected to said device, collecting a voltage of the second end of the switch unit, and determining that electromigration occurs in the switch unit when the voltage of the second end is not zero, wherein the output level of the first drive signal is the same as the output level of a first drive signal provided for the drive circuit by means of the first pin during charging of said device.

Description

Equipment to be charged and charging method

Technical field

The present disclosure relates to the field of charging technology, and in particular to a device to be charged and a charging method.

Background technique

Devices to be charged (such as smart phones, mobile terminals, or smart devices) are becoming more and more popular among consumers, but the devices to be charged consume a lot of power and need to be charged frequently, and the use of low-power ordinary charging solutions to charge the charging devices is usually It takes several hours. In order to cope with this challenge, the industry has proposed a fast charging solution for charging the device to be charged by increasing the charging power of the device to be charged.

In order to increase the charging power of the device to be charged to achieve the purpose of fast charging, one solution is to use a large current to charge the device to be charged. The greater the charging current, the faster the charging speed of the device to be charged. In a fast charging scheme that uses high current for charging, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor, hereinafter referred to as MOS transistor) is usually set to be electrically connected to the battery in the device to be charged, such as Control modules such as MCU (Microcontroller Unit) control the drive circuit electrically connected to the MOS tube to realize the turn-on and turn-off of the MOS tube, so as to realize the turn-on and exit of the fast charging.

For this connection method, since the battery is always charged, that is, the battery voltage is not 0, electromigration may occur between the first pole and the third pole of the MOS tube connected to the battery, resulting in the third pole of the MOS tube The impedance between the first pole and the first pole is reduced, the leakage of the first pole and the voltage of the third pole for driving the MOS tube to turn on are reduced, which causes the conduction impedance between the second pole and the first pole to be too large when it is turned on. , The lower the voltage between the third pole and the first pole, the greater the conduction resistance when the MOS tube is turned on. If the on-resistance is too high during fast charging, it will cause serious heating of the device to be charged and the problem of exiting fast charging. With the use of dual-cell batteries, the voltage of mobile phone batteries is getting higher and higher, and MOS tube electromigration will become more serious.

The above-mentioned information disclosed in the background section is only used to enhance the understanding of the background of the present disclosure, so it may include information that does not constitute the prior art known to those of ordinary skill in the art.

Summary of the invention

In view of this, the present disclosure provides a device to be charged and a charging method.

Other characteristics and advantages of the present disclosure will become apparent through the following detailed description, or partly learned through the practice of the present disclosure.

According to one aspect of the present disclosure, there is provided a device to be charged, including: a charging interface; a battery unit; and a switch unit, including a first end, a second end, and a third end, the first end is connected to the battery unit, The second end is connected to the charging interface; a driving circuit is connected to the third end of the switch unit and is used to drive the on and off of the switch unit; and the control unit is connected to the charging interface, It is used to detect whether there is a power supply device connected to the device to be charged through the charging interface; when it is detected that no power supply device is connected to the device to be charged, provide the drive circuit through the first pin First drive signal, and collect the voltage of the second terminal of the switch unit; and when the voltage of the second terminal is not zero, determine that the switch unit has electromigration; wherein, the output of the first drive signal The level is the same as the output level of the first driving signal provided to the driving circuit through the first pin when the device to be charged is charging.

According to an embodiment of the present disclosure, the control unit includes: a first control unit and a second control unit; wherein the first control unit is connected to the charging interface for detecting whether there is a power source through the charging interface The providing device is connected to the device to be charged; and when it is detected that the power supply device is not connected to the device to be charged, sending a signal collection instruction to the second control unit; the second control unit is connected to the The first control unit and the first drive circuit are connected, and are used to provide the first drive signal to the drive circuit through the first pin when the signal collection instruction is received, and collect all the signals. The voltage of the second terminal of the switch unit; and when the voltage of the second terminal is not zero, it is determined that the switch unit has electromigration.

According to an embodiment of the present disclosure, the switch unit includes: a first MOS transistor and a second MOS transistor, wherein the first pole of the first MOS transistor is connected to the battery unit through the first end, and the The first electrode of the second MOS transistor is connected to the charging interface through the second end, the second electrode of the first MOS transistor is connected to the second electrode of the second MOS transistor, and the first MOS transistor The third pole of the tube is connected to the third pole of the second MOS tube; the second control unit is used to determine when the voltage of the second terminal is not zero, the first pole of the first MOS tube is connected to the Electromigration occurred between the third poles.

According to an embodiment of the present disclosure, the second control unit is further configured to perform a charging process on the device to be charged after it is determined that electromigration has occurred between the first pole and the third pole of the first MOS tube Determining whether the sum of the first impedance between the second pole and the first pole of the first MOS tube and the second impedance between the second pole and the first pole of the second MOS tube is less than a predetermined value When it is determined that the sum of the first impedance and the second impedance is less than the impedance threshold, the voltage of the third electrode of the first MOS transistor is reduced.

According to an embodiment of the present disclosure, the control unit includes: a first control unit and a second control unit; wherein the first control unit is connected to the charging interface for detecting whether there is a power source through the charging interface The providing device is connected to the device to be charged; and when it is detected that the power supply device is not connected to the device to be charged, sending a signal collection instruction to the second control unit; the second control unit is connected to the The first control unit and the drive circuit are connected, and are used to provide the first drive signal to the drive circuit through the first pin when the signal acquisition instruction is received; the first control unit It is also used to collect the voltage at the second end of the switch unit after the second control unit provides the first drive signal to the drive circuit through the first pin; and when the voltage at the second end When it is not zero, it is determined that the switch unit has electromigration.

According to an embodiment of the present disclosure, the switch unit includes: a first MOS transistor and a second MOS transistor, wherein the first pole of the first MOS transistor is connected to the battery unit through the first end, and the The first electrode of the second MOS transistor is connected to the charging interface through the second end, the second electrode of the first MOS transistor is connected to the second electrode of the second MOS transistor, and the first MOS transistor The third pole of the tube is connected to the third pole of the second MOS tube; the first control unit is used to determine when the voltage of the second terminal is not zero, the first pole of the first MOS tube is connected to the Electromigration occurred between the third poles.

According to an embodiment of the present disclosure, the first control unit is further configured to perform a charging process on the device to be charged after it is determined that electromigration has occurred between the first pole and the third pole of the first MOS tube , Sending a voltage adjustment instruction to the second control unit to instruct the second control unit to determine whether to reduce the voltage of the third pole of the first MOS transistor.

According to an embodiment of the present disclosure, the second control unit is further configured to determine the first impedance and the impedance between the second pole and the first pole of the first MOS tube when the voltage adjustment instruction is received. Whether the sum of the second impedance between the second pole and the first pole of the second MOS transistor is less than a preset impedance threshold; and when it is determined that the sum of the first impedance and the second impedance is less than the impedance At the threshold value, the voltage of the third pole of the first MOS tube is reduced.

According to an embodiment of the present disclosure, the second control unit is further configured to reduce the duty cycle of the second driving signal provided to the driving circuit through the second pin, so as to reduce the first MOS transistor. Three-pole voltage; wherein the second drive signal is used to provide a drive voltage for the drive circuit.

According to an embodiment of the present disclosure, the second control unit is further configured to provide the first driving signal whose output signal is a square wave to the driving circuit to reduce the voltage of the third electrode of the first MOS transistor .

According to an embodiment of the present disclosure, the second control unit is further configured to collect the voltage of the first pole of the second MOS tube and the voltage of the first MOS tube during the charging process of the device to be charged. The voltage and charging current of the first pole, and the first impedance and the charging current are determined according to the voltage of the first pole of the second MOS tube, the voltage of the first pole of the first MOS tube, and the charging current. The sum of the second impedance.

According to an embodiment of the present disclosure, the second control unit is further configured to receive the output voltage and output current fed back by the power supply device during the charging process of the device to be charged, and collect the voltage of the battery unit, And determining the sum of the first impedance and the second impedance according to the output current, the output current, and the voltage of the battery cell.

According to an embodiment of the present disclosure, the second control unit is further configured to provide the driving circuit with the driving circuit through the first pin after the voltage of the first pole of the second MOS tube is collected. The first drive signal is used to control the drive circuit to reset.

According to another aspect of the present disclosure, there is provided a charging method applied to a device to be charged, the method comprising: detecting whether a power supply device is connected to the device to be charged; when it is detected that the power supply device is not connected to the device to be charged; When the device to be charged is connected, the first drive signal is provided to the drive circuit through the first pin, and the voltage at the second end of the switch unit is collected; and when the voltage at the second end is not zero, it is determined that the switch unit is The electromigration; wherein, the second end of the switch unit is connected to the charging interface of the device to be charged; the output level of the first drive signal and the device to be charged pass the first The output levels of the first driving signals provided by the pins to the driving circuit are the same.

According to an embodiment of the present disclosure, the switch unit includes: a first MOS tube and a second MOS tube, wherein the first pole of the first MOS tube passes through the first terminal and the battery unit of the device to be charged Connected, the first pole of the second MOS transistor is connected to the charging interface through the second end, and the second pole of the first MOS transistor is connected to the second pole of the second MOS transistor, so The third pole of the first MOS transistor is connected to the third pole of the second MOS transistor; determining that the switch unit has electromigration includes: determining the first pole of the first MOS transistor and the third pole Electromigration occurred between.

According to an embodiment of the present disclosure, the method further includes: when it is determined that electromigration has occurred between the first pole and the third pole of the first MOS transistor, determining that during the charging process of the device to be charged Whether the sum of the first impedance between the second pole and the first pole of the first MOS tube and the second impedance between the second pole and the first pole of the second MOS tube is less than a preset impedance Threshold; and when it is determined that the sum of the first impedance and the second impedance is less than the impedance threshold, reducing the voltage of the third electrode of the first MOS tube.

According to an embodiment of the present disclosure, reducing the voltage of the third electrode of the first MOS transistor includes: reducing the duty cycle of the second driving signal provided to the driving circuit through the second pin; wherein, The second driving signal is used to provide a driving voltage for the driving circuit.

According to an embodiment of the present disclosure, reducing the voltage of the third electrode of the first MOS transistor includes: providing the first driving signal whose output signal is a square wave to the driving circuit.

According to an embodiment of the present disclosure, the first impedance between the second pole and the first pole of the first MOS tube and the second impedance between the second pole and the first pole of the second MOS tube are determined Whether the sum is less than a preset impedance threshold includes: during the charging process of the device to be charged, separately collecting the voltage of the first electrode of the second MOS tube and the voltage of the first electrode of the first MOS tube And a charging current; determining the sum of the first impedance and the second impedance according to the voltage of the first pole of the second MOS tube, the voltage of the first pole of the first MOS tube, and the charging current; and It is determined whether the sum of the first impedance and the second impedance is less than the impedance threshold.

According to an embodiment of the present disclosure, the first impedance between the second pole and the first pole of the first MOS tube and the second impedance between the second pole and the first pole of the second MOS tube are determined Whether the sum is less than a preset impedance threshold includes: during the charging process of the device to be charged, receiving the output voltage and output current fed back by the power supply device, and collecting the voltage of the battery unit; according to the output current , The output current and the voltage of the battery cell, determine the sum of the first impedance and the second impedance; and determine whether the sum of the first impedance and the second impedance is less than the impedance threshold.

According to an embodiment of the present disclosure, the method further includes: after collecting the first electrode voltage of the second MOS transistor, providing the first driving signal to the driving circuit through the first pin, To control the drive circuit to reset.

According to the device to be charged in the embodiment of the present disclosure, when the device to be charged is not connected to the power supply device, the voltage of the second end of the switch unit (the end connected to the charging interface of the device to be charged) can be collected and collected by the control unit. Judgment to determine whether electromigration has occurred in the switch unit. Therefore, the problem of increased impedance of the fast charging path caused by the electromigration of the switch unit, reduction of the fast charging current and even withdrawal of the fast charging can be avoided.

It should be understood that the above general description and the following detailed description are only exemplary and cannot limit the present disclosure.

Description of the drawings

By describing its exemplary embodiments in detail with reference to the accompanying drawings, the above and other objectives, features, and advantages of the present disclosure will become more apparent.

Fig. 1 is a block diagram showing a device to be charged according to an exemplary embodiment.

Fig. 2 is a circuit diagram showing a switch unit 13 and a driving circuit 14 according to an exemplary embodiment.

Fig. 3 is a schematic diagram showing the relationship between the impedance between the drain and the source of the MOS transistor and the voltage between the gate and the source according to an example.

Fig. 4 is a schematic diagram showing collecting the voltage VBAT0 and the voltage VBUS according to an exemplary embodiment.

Fig. 5 is a flowchart showing a charging method according to an exemplary embodiment.

Fig. 6 is a flow chart showing another charging method according to an exemplary embodiment.

Fig. 7 is a flowchart showing still another charging method according to an exemplary embodiment.

Fig. 8 is a flowchart showing yet another charging method according to an exemplary embodiment.

Fig. 9 is a flowchart showing yet another charging method according to an exemplary embodiment.

Detailed ways

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms, and should not be construed as being limited to the examples set forth herein; on the contrary, the provision of these embodiments makes the present disclosure more comprehensive and complete, and fully conveys the concept of the example embodiments To those skilled in the art. The drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures denote the same or similar parts, and thus their repeated description will be omitted.

Furthermore, the described features, structures or characteristics can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to give a sufficient understanding of the embodiments of the present disclosure. However, those skilled in the art will realize that the technical solutions of the present disclosure can be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. can be used. In other cases, well-known structures, methods, devices, implementations, or operations are not shown or described in detail to avoid overwhelming attention and obscure all aspects of the present disclosure.

In the present disclosure, unless expressly stipulated and defined otherwise, the terms "connected", "connected", and other terms should be understood in a broad sense. For example, they may be electrically connected or communicate with each other; they may be directly connected or intervening. The medium is indirectly connected. For those of ordinary skill in the art, the specific meaning of the above-mentioned terms in the present disclosure can be understood according to specific circumstances.

In addition, in the description of the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined. "And/or" describes the association relationship of the associated objects, indicating that there can be three relationships, such as A and/or B, which can indicate the existence of A alone, B alone, and both A and B. The symbol "/" generally indicates that the associated objects are in an "or" relationship. The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of these features.

Before introducing the embodiments of the present disclosure, the "normal charging mode" and the "fast charging mode" in the charging system will be described first. The normal charging mode means that the adapter outputs a relatively small current value (usually less than 2.5A) or uses a relatively small power (usually less than 15W) to charge the battery in the charging device. It usually takes several hours to fully charge a larger capacity battery (such as a 3000 mAh battery) in the normal charging mode. Fast charging mode means that the adapter can output a relatively large current (usually greater than 2.5A, such as 4.5A, 5A or even higher) or relatively large power (usually greater than or equal to 15W) to treat the battery in the charging device Recharge. Compared with the normal charging mode, the charging speed of the adapter in the fast charging mode is faster, and the charging time required to fully charge the battery of the same capacity can be significantly shortened.

During the charging process, power supply devices (such as power adapters, power banks, etc.) are generally connected to the device to be charged through cables, and the power provided by the power supply device is transmitted to the device to be charged through the cable. Charging with charging equipment.

The device 10 to be charged as shown in FIG. 1 may be, for example, a terminal or a communication terminal. The terminal or communication terminal includes but is not limited to being set to be connected via a wired line, such as via a public switched telephone network (PSTN), Digital subscriber line (DSL), digital cable, direct cable connection, and/or another data connection/network and/or via, for example, cellular network, wireless local area network (WLAN), such as handheld Digital video broadcasting (digital video broadcasting handheld, DVB-H) network digital TV network, satellite network, amplitude modulation-frequency modulation (AM-FM) broadcast transmitter, and/or the wireless interface of another communication terminal A device for receiving/sending communication signals. A communication terminal set to communicate through a wireless interface may be referred to as a "wireless communication terminal", a "wireless terminal" and/or a "mobile terminal". Examples of mobile terminals include, but are not limited to, satellite or cellular phones; personal communication system (PCS) terminals that can combine cellular radio phones with data processing, fax, and data communication capabilities; can include radio phones, pagers, and the Internet/ Personal digital assistant (PDA) with intranet access, web browser, memo pad, calendar, and/or global positioning system (GPS) receiver; and conventional laptop and/or palmtop Receiver or other electronic device including a radio telephone transceiver. In addition, the terminal can also include, but is not limited to, electronic book readers, smart wearable devices, mobile power sources (such as power banks, travel chargers), electronic cigarettes, wireless mice, wireless keyboards, wireless headphones, Bluetooth speakers, etc. Rechargeable electronic equipment.

1, the device to be charged 10 includes: a charging interface 11, a battery unit 12, a switch unit 13, a driving circuit 14 and a control unit 15.

The device 10 to be charged is connected to the power supply device 20 through the charging interface 11 to charge the battery unit 12. The charging interface 11 may be, for example, a USB 2.0 interface, a Micro USB interface, or a USB TYPE-C interface. In some embodiments, the charging interface 11 may also be a lightning interface, or any other type of parallel port or serial port that can be used for charging.

The battery cell 12 may be a lithium battery containing a single lithium battery cell, or a lithium battery containing multiple lithium battery cells, or the battery cell 12 may also contain multiple battery cells, each of which contains one or more Lithium battery cells.

For a device to be charged that contains a single battery cell, when a larger charging current is used to charge the single battery cell, the heating phenomenon of the device to be charged is more serious. In order to ensure the charging speed of the device to be charged, and to alleviate the heating phenomenon of the device to be charged during the charging process, the battery structure can be modified to use multiple battery cells connected in series and directly charge the multiple battery cells. The voltage output by the adapter is directly applied to the two ends of the battery unit containing multiple cells. Compared with the single-cell solution (that is, the capacity of the single-cell before the improvement is the same as the total capacity of the multiple-cell series after the improvement), if the same charging speed is to be achieved, the charging current required by the multiple-cell is about It is 1/N of the charging current required by a single cell (N is the number of cells connected in series). In other words, under the premise of ensuring the same charging speed, series connection of multiple cells can greatly reduce the size of the charging current , Thereby further reducing the heat generated by the device to be charged during the charging process.

The switch unit 13 includes a first terminal p1, a second terminal p2, and a third terminal p3. The first terminal p1 is connected to the battery unit 12, the second terminal p2 is connected to the charging interface 11, and the third terminal p3 is connected to the driving circuit 14.

The driving circuit 14 is used to drive the switch unit 13 to turn on and off, thereby controlling the on and off of the fast charging.

The control unit 15 is connected to the charging interface 11 for detecting whether there is a power supply device 20 connected to the device to be charged 10 through the charging interface 11; and when it is detected that no power supply device 20 is connected to the device 10 to be charged, the first guide The pin (Pin1 in Figure 2) provides the first drive signal to the drive circuit 14, and collects the voltage at the second end of the switch unit 13; and when the voltage at the second end is not zero, it is determined that the switch unit 13 is electrically powered. migrate. The output level of the first driving signal is the same as the output level of the first driving signal provided to the driving circuit through the first pin when the device to be charged 10 is charging.

The following takes the circuit diagram of the switch unit 13 and the drive circuit 14 shown in FIG. 2 as an example to further explain how the control unit 15 determines whether the MOS tube in the switch unit 13 has undergone electromigration, and how to recover after the electromigration occurs. MOS tube for electromigration.

Referring to FIG. 2, the switch unit 13 includes, for example, a first MOS transistor V1 and a second MOS transistor V2. The first electrode (such as the source electrodes S_0 to S_2) of the first MOS transistor V1 passes through the first terminal p1 and the battery unit 12 Connected, the first electrode of the second MOS transistor V2 (such as the source S_0~S_2) is connected to the charging interface 11 through the aforementioned second terminal p2, and the second electrode (such as the drain D) of the first MOS transistor V1 is connected to the second The second electrode (such as the drain D) of the MOS transistor V2 is connected, and the third electrode (such as the gate G) of the first MOS transistor V1 is connected with the third electrode (such as the gate G) of the second MOS transistor V2. That is, the first MOS tube V1 and the second MOS tube are connected in reverse series.

It should be noted that the first MOS transistor V1 and the second MOS transistor V2 in FIG. 2 are all NMOS transistors as examples, and NMOS transistors are also used as examples in the following description and principle explanation. However, those skilled in the art can understand how to apply the method provided by the embodiments of the present disclosure when both the first MOS transistor V1 and the second MOS transistor V2 are replaced with PMOS transistors based on the same inventive concept.

1 and 2 jointly, during the fast charging process of the device 10 to be charged (such as connecting a fast charging adapter, the fast charging adapter can output a relatively large current (usually greater than 2.5A, such as 4.5A, 5A or even higher) Or output relatively large power (usually greater than or equal to 15W)), the control unit 15 provides the first driving signal Fast_switch to the driving circuit 14 through the pin Pin1, and the first driving signal Fast_switch is set to a low level. The MOS transistor V5 in the driving circuit 14 is turned off due to the first driving signal Fast_switch being set to a low level, and the voltage VBUS output by the power supply device 20 is loaded between the diode D1 and the diode D2 through the diode D1. The second driving signal CLK_OUT provided by the control unit 15 to the driving circuit 14 through the pin Pin2 is a square wave signal, which is also loaded between the diode D1 and the diode D2. In order to reduce the consumption of capacitor C2 and the power consumption of the overall charging circuit, the resistance value of resistor R3 is usually relatively large (for example, above 100K ohms), and the current flowing through resistors R1, R2, and R3 is very small. The voltage drop caused by the resistance is also very small. Therefore, the level between the diode D1 and the diode D2 is [(VBUS-Vd)+Vclk], where Vd represents the voltage drop on the diode D1 or D2, and Vclk represents the voltage of the square wave signal CLK_OUT. After the diode D2 is rectified, the level between the diode D2 and the resistor R2 becomes [(VBUS-2Vd)+Vclk], and after the resistor R2, the gate voltage of the first MOS transistor V1 and the second MOS transistor V2 Is (Vclk-2Vd), and the voltage between the gate and source of the first MOS tube V1 is [(VBUS-VBAT0)+(Vclk-2Vd)], so as to realize the first MOS tube V1 and the second MOS tube V2 is turned on.

At present, in the related art, during fast charging, the charging current I is larger. It can be seen from P=I2R that the larger the current I, the larger the power P and the more serious the heat. In order to prevent the abnormalities of some local components on the fast charging path from causing serious heating or even burning, and to ensure the safety of the equipment to be charged, the path impedance control is designed, and the corresponding impedance can be adjusted according to the size of the fast charging path impedance R Current value. The device to be charged sends the voltage at both ends of the battery or the voltage detected on the charging path of the battery (assuming V1) in real time to the power supply through the data lines (D+ and D-) on the cable connecting the power supply device and the device to be charged Provide device. The power supply device compares V1 with its own output voltage (assumed to be V0), and divides it by the current I output by the adapter to obtain the path impedance R, R=(V0-V1)/I. The specific control method of path impedance is shown in Table 1.

Table 1

阻抗impedance	R≤R1R≤R1	R1＜R≤R2R1＜R≤R2	R2＜R≤R3R2＜R≤R3	R＞R3R＞R3
快充电流Fast charge flow	I1I1	I2I2	I3I3	退出快充Quit fast charge

Among them, when the path impedance R is less than the resistor R1 shown in Figure 2, the current I1 is used for fast charging; when the path impedance R increases to greater than the resistor R1 and less than or equal to the resistor R2, the charging current of the path decreases to I2 for fast charging. Charging (I2 is less than I1); when the path impedance R continues to increase to greater than the resistance R2 and less than or equal to the resistance R2, the charging current of the path decreases to I3 for fast charging (I3 is less than I2); when the path resistance R continues to increase to When it is greater than the resistance R3, the fast charging is exited and ordinary charging is performed.

1 and FIG. 2 jointly, for the circuit shown in FIG. 2, since there is always electricity in the battery cell 12, the first terminal p1 is connected to the battery cell 12 through the source and gate of the first MOS transistor V1 Electromigration may occur between the first MOS transistor V1, the impedance between the gate and the source of the first MOS transistor V1 will decrease, the source will leak and cause the gate voltage for driving the first MOS transistor V1 to turn on to drop, thereby causing the When a MOS transistor V1 is turned on, the impedance between the drain and the source increases. If the impedance between the drain and the source is too large, as described above, it will cause serious heat generation and withdrawal from fast charging.

As shown in Figure 3, under different VGS (voltage between gate and source), the relationship between ID (drain current) and VDS (voltage between drain and source) is: RDS=VDS /ID. It can be seen from Figure 3 that the lower the VGS, the larger the impedance RDS when the MOS tube is turned on. In particular, if VGS is too low, when the MOS tube is turned on, the on-resistance RDS is too large, which causes the impedance of the entire fast charging path to be too large, reducing the fast charging current or exiting the fast charging.

In order to solve the above problems, the embodiments of the present disclosure provide a device to be charged. When the device to be charged is not connected to a power supply device, when electromigration occurs between the source and the gate of the first MOS transistor V1, the first Based on the principle that the impedance between the gate and the source of the MOS transistor V1 will become smaller, it is detected whether the first MOS transistor V1 has electromigration. And during the subsequent fast charging, the voltage of the first MOS transistor V1 that has undergone electromigration is adjusted to restore the electromigration state.

In the following, in conjunction with FIG. 1 and FIG. 2, it is further described how the device to be charged according to the embodiment of the present disclosure performs the electromigration detection of the MOS tube and how to recover the MOS tube that has undergone electromigration.

In some embodiments, the control unit 15 may further include: a first control unit 151 and a second control unit 152.

1, the first control unit 151 may be, for example, an Application Processor (AP) in the device to be processed 10, connected to the charging interface 11, and used to detect whether there is a power supply device 20 and the device to be charged through the charging interface. 10Connect. For example, the first control unit 151 may communicate with the power supply device 20 to detect whether the power supply device 20 is connected to the device 10 to be charged.

The first control unit 151 may communicate with the power supply device 20 through the charging interface 11, for example, without setting an additional communication interface or other wireless communication module. If the charging interface 11 is a USB interface, the first control unit 151 and the power supply device 20 can communicate based on a data line (such as a D+ and/or D- line) in the USB interface. For another example, the charging interface 11 is a USB interface (such as a USB TYPE-C interface) supporting a power transmission (PD) communication protocol, and the first control unit 151 and the power supply device 20 may communicate based on the PD communication protocol. In addition, the first control unit 151 may also be communicatively connected with the power supply device 20 through other communication methods than the charging interface 11. For example, the first control unit 151 may communicate with the power supply device 20 in a wireless manner, such as near field communication.

For example, the first control unit 151 may start to detect whether the power supply device 20 is connected to the device to be charged 10 after the device to be charged 10 is turned on and the second control unit 152 is reset; and/or the first control unit 151 may also be After the power supply device 20 is unplugged, it waits for a predetermined time (for example, 2S), and starts to detect whether the power supply device 20 is connected to the device 10 to be charged.

When the first control unit 151 detects that no power supply device 20 is connected to the device 10 to be charged, it can send a signal collection instruction to the second control unit 152.

The second control unit 152 may be, for example, a control module provided for controlling fast charging, such as an MCU.

The second control unit 152 is connected to the first control unit 151 and the driving circuit 14 respectively, and is configured to receive a signal collection instruction sent by the first control unit 151. When the signal collection instruction is received, the first driving signal (such as the driving signal Fast_switch) is provided to the driving circuit 14 through the first pin (Pin1 in FIG. 2), and the voltage of the second terminal p2 of the switch unit 13 is collected. It is determined whether the voltage of the second terminal p2 of the switch unit 13 is zero, and when it is not zero, it is determined that the switch unit 13 has electromigration. Taking the MOS transistor included in the switch unit 13 as an example, it is determined that the MOS transistor in the switch unit 13 has electromigration.

The output level of the first driving signal is the same as the output level of the first driving signal Fast_switch provided to the driving circuit 14 through the first pin Pin1 during the fast charging of the device 10 to be charged, that is, the output is low.

According to another embodiment of the present disclosure, after the second control unit 152 provides the first drive signal Fast_switch to the drive circuit 14 through the first pin Pin1, the first control unit 151 may also collect the first drive signal of the switch unit 13 The voltage of the two terminals is used to determine whether the switch unit 13 has electromigration. Since the first control unit 151 can be the application processor of the device 10 to be charged, the first control unit 151 collects the voltage of the second terminal of the switch unit 13, which is more accurate and has stronger processing capabilities, while avoiding The situation that the collected information is lost when the second control unit 152 is reset occurs. In addition, when the first control unit 151 determines that the switch unit 13 has electromigration, the first control unit 151 is also used to send a voltage adjustment instruction to the second control unit 152 when the device 10 to be charged is subsequently fast-charged, to indicate The second control unit 152 restores the switch unit 13 in which electromigration has occurred through voltage adjustment.

In some embodiments, referring to FIGS. 1 and 2 jointly, when the second control unit 152 receives the above-mentioned signal collection instruction, it provides the first driving signal Fast_switch to the driving circuit 14 through the pin Pin1, and the first driving signal Fast_switch is set to a low level, the MOS transistor V5 is turned off, and the gates of the first MOS transistor V1 and the second MOS transistor V2 are grounded through a resistor R3. If the impedance between the gate and the source of the first MOS transistor V1 becomes smaller, the voltage VG on the gate is the divided voltage between RGS (the impedance between the gate and the source) and R3. The voltage VG on the gate of the first MOS tube exceeds the cut-off voltage Vth of the second MOS tube V2, and the second MOS tube V2 is turned on, so the source voltage VBUS of the second MOS tube (connected to the power supply device 20) Not 0. Therefore, it can be determined whether electromigration has occurred in the first MOS transistor V1 by detecting the voltage VBUS of the source of the second MOS transistor. If the first MOS tube V1 does not undergo electromigration, the collected source voltage VBUS of the second MOS tube is not zero; otherwise, the collected source voltage VBUS of the second MOS tube is zero. That is, the voltage of the second terminal of the switch unit 13 collected by the first control unit 151 or the second control unit 152 is the voltage of the source of the second MOS transistor V2.

It should be noted that, in order to accurately collect the VBUS voltage, after the first driving signal is set to a low level, it can be delayed for a certain time (such as 1s) before collecting the VBUS. And after the VBUS voltage is collected, the first driving signal Fast_switch needs to be reset to a high level.

When the second control unit 152 determines that the switch unit 13 has undergone electromigration, or when the second control unit 152 receives the above-mentioned voltage adjustment instruction sent by the first control unit 151, during the fast charging process of the device 10 to be charged, Determine whether the total impedance of the switch unit 13 is less than a preset impedance threshold; and when the total impedance of the switch unit 13 is less than the impedance threshold, adjust the voltage of the switch unit 13 to restore the switch unit 13 that has undergone electromigration.

If it is detected that a certain degree of electromigration problem has occurred (that is, the voltage of VBUS reaches a certain degree), when the device to be charged 10 enters fast charging, the MOS tube can be heated to change the electromigration problem. But when the first MOS tube V1 only undergoes slight electromigration, the path impedance is relatively small during the subsequent fast charging process. It can be seen from P=I2R that the heat generation at this time is relatively small, and the temperature of the MOS tube is relatively low. The electromigration state of the MOS tube cannot be restored at this temperature. In order to improve the electromigration problem, the problem of the MOS tube needs to be improved.

Therefore, the device to be charged in the embodiment of the present disclosure further provides a method of how to determine that the first MOS transistor has only a slight electromigration, and how to restore the first MOS transistor in a state of slight electromigration.

1 and FIG. 2 jointly, when the second control unit 152 determines that electromigration has occurred between the source and the gate of the first MOS transistor V1 in the switch unit 13, the drain and the gate of the first MOS transistor V1 can pass through The sum of the first impedance between the sources and the second impedance between the drain and the source of the second MOS transistor V2 determines the degree of electromigration of the first MOS transistor V1. Compare the sum of the first impedance between the drain and source of the first MOS transistor V1 and the second impedance between the drain and source of the second MOS transistor V2 with a preset impedance threshold, if less than This impedance threshold determines that only slight electromigration has occurred in the first MOS transistor V1, and it is improved by the following method. In practical applications, the impedance threshold can be set according to actual requirements, and the present disclosure is not limited to this.

In some embodiments, the second control unit 152 can use the ADC (Analog-to-Digital Converter) of the second control unit 152 to collect VBAT0 and VBUS, that is, collecting the source voltage of the first MOS tube and the source voltage of the second MOS tube. The acquisition principle is shown in Figure 4(a) and (b) respectively. The waiting voltages VBAT0 and VBUS can be collected through pin Vbat_ADC and pin Vbus_ADC, respectively. Among them, the resistors R5, R6, R7, and R8 and the capacitors C7 and C8 are equivalent resistors and capacitors in the second control unit 152, respectively. After the second control unit 152 collects the voltages VBAT0 and VBUS, according to the formula R=(VBUS-VBAT0)/I, the impedance between the drain and the source of the first MOS transistor V1 and the second MOS transistor V2 can be obtained. The sum of impedance R between the drain and source. Where I is the charging current collected by the second control unit 152.

In some embodiments, the second control unit 152 may also receive the output voltage VBUS and the output current I fed back by the power supply device 20 during the fast charging process of the device 10 to be charged, and according to the output voltage VBUS and the output current I And the collected voltage VBAT0 through the above formula R=(VBUS-VBAT0)/I to calculate the impedance between the drain and source of the first MOS transistor V1 and the impedance between the drain and source of the second MOS transistor V2 The sum of impedance R. The collection of voltage VBAT0 can refer to Figure 4(a).

The second control unit 152 may communicate with the power supply device 20 through the charging interface 11, for example, without setting an additional communication interface or other wireless communication module. If the charging interface 11 is a USB interface, the second control unit 152 and the power supply device 20 can communicate based on the data lines (such as D+ and/or D- lines) in the USB interface. For another example, the charging interface 11 is a USB interface (such as a USB TYPE-C interface) supporting a power transmission (PD) communication protocol, and the second control unit 152 and the power supply device 20 may communicate based on the PD communication protocol. In addition, the second control unit 152 may also be communicatively connected to the power supply device 20 through other communication methods than the charging interface 11. For example, the second control unit 152 may communicate with the power supply device 20 in a wireless manner, such as near field communication.

In order to restore the first MOS transistor V1 that has undergone electromigration, the embodiment of the present disclosure chooses to increase its impedance when the charging current is large. Usually, the fast charging current is large when the power of the device to be charged is low, so you can choose Adjust the gate voltage of the first MOS tube when the device to be charged is quickly charged with low power.

In some embodiments, the second control unit 152 reduces the duty cycle of the second driving signal CLK_OUT of the driving driving circuit 14 when the device 10 to be charged is fast charging, and the voltage increased by the charging and discharging of the capacitor C1 is controlled by the circuit. On the principle of consumption (such as the resistance R3 being grounded, etc.), the gate voltages of the first MOS transistor V1 and the second MOS transistor V2 will decrease and cannot reach [(VBUS-2Vd)+Vclk]. It should be noted that the second driving signal CLK_OUT should be output at a faster frequency, so that the ripple will be relatively small, and the gate voltages of the first MOS transistor V1 and the second MOS transistor V2 are relatively stable.

In some embodiments, the second control unit 152 may also provide the first driving signal Fast_switch whose output signal is a square wave to the driving circuit 14 when the device 10 to be charged is fast charging, so as to reduce the gate voltage of the first MOS transistor. . The first driving signal Fast_switch signal outputs a square wave signal. When the MOS transistor V5 is turned on, it consumes the voltage generated by the charging and discharging of the capacitor C1, and reduces the gate voltage of the first MOS transistor V1 and the second MOS transistor V2.

In addition, the first MOS tube V1 and the second MOS tube V2 can also be heated to a certain temperature, so as to restore the first MOS tube that has undergone electromigration.

In addition, during charging, while adjusting the gate voltages of the first MOS transistor V1 and the second MOS transistor V2 by the above method, the first control unit 151 of the device to be charged 10 can be operated at a high speed, so that The device 10 generates a large amount of heat, thereby recovering the first MOS tube that has undergone electromigration.

According to the device to be charged in the embodiments of the present disclosure, when the device to be charged is not connected to the power supply device, the first control unit or the second control unit can collect and judge the source voltage of the second MOS transistor to determine the first Whether electromigration has occurred in a MOS tube. Furthermore, by judging the sum of the impedance of the drain and source of the first MOS transistor and the sum of the impedance of the drain and source of the second MOS transistor, it is determined whether the first MOS transistor has only slight electromigration, If only slight electromigration has occurred, the first MOS transistor that has undergone slight electromigration can be restored by adjusting the gate voltage of the first MOS transistor. This effectively avoids the problems of increased impedance of the fast charging path, reduced fast charging current, and even withdrawal of fast charging caused by the electromigration of the MOS tube.

It should be noted that the block diagram shown in the above drawings is a functional entity, and does not necessarily correspond to a physically or logically independent entity. These functional entities may be implemented in the form of software, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and/or processor devices and/or microcontroller devices.

The following are the embodiments of the disclosed method, which can be applied to the above-mentioned embodiments of the disclosed device. For details not disclosed in the method embodiments of the present disclosure, please refer to the device embodiments of the present disclosure.

Referring to FIG. 5, the charging method 70 may be applied to the device to be charged 10 shown in FIGS. 1 and 2 described above. Referring to FIG. 1, FIG. 2 and FIG. 6, the charging method 70 includes:

In step S702, it is detected whether there is a power supply device 20 connected to the device 10 to be charged.

In step S704, when it is detected that no power supply device 20 is connected to the device to be charged 10, the first driving signal Fast_switch is provided to the driving circuit 14 through the first pin Pin1, and the voltage of the second terminal p2 of the switch unit 13 is collected ; And when the voltage of the second terminal p2 is not zero, it is determined that the switch unit 13 has electromigration.

The output level of the first driving signal Fast_switch is the same as the output level of the first driving signal Fast_switch provided to the driving circuit 14 through the first pin Pin1 when the device to be charged 10 is charging.

According to the charging method of the embodiment of the present disclosure, when the device to be charged is not connected to the power supply device, the voltage of the second end of the switch unit (the end connected to the charging interface of the device to be charged) can be collected and judged. Determine whether electromigration has occurred in the switch unit. Therefore, the problem of increased impedance of the fast charging path caused by the electromigration of the switch unit, reduction of the fast charging current and even withdrawal of the fast charging can be avoided.

Referring to FIG. 6, the charging method 30 may be applied to the device to be charged 10 shown in FIGS. 1 and 2 described above. Referring to FIG. 1, FIG. 2 and FIG. 6, the charging method 30 includes:

In step S302, the first control unit 151 detects through the charging interface 11 whether there is a power supply device 20 connected to the device 10 to be charged.

In step S304, when it is detected that no power supply device 20 is connected to the device to be charged 10, the first control unit 151 sends a signal collection instruction to the second control unit 152.

In step S306, when the signal collection instruction is received, the second control unit 152 provides the first drive signal Fast_switch to the drive circuit 14 through the first pin Pin1, and collects the voltage of the second terminal of the switch unit 13; and When the voltage at the terminal is not zero, it is determined that the switch unit 13 has electromigration.

Wherein, the output level of the first drive signal Fast_switch is the same as the output level of the first drive signal Fast_switch provided to the drive circuit 14 through the first pin Pin1 when the device to be charged 10 is charging (that is, set to a low level) .

In some embodiments, determining that electromigration has occurred in the switch unit 13 includes: determining that electromigration has occurred between the first pole and the third pole of the first MOS transistor V1.

In some embodiments, the charging method 40 further includes: after collecting the first pole voltage of the second MOS transistor V2, controlling the driving circuit 14 to reset by the first driving signal Fast_switch, that is, setting the first driving signal Fast_switch to a high level .

Fig. 7 is a flowchart showing another charging method according to an exemplary embodiment. Similarly, the charging method 40 shown in FIG. 7 can be applied to the device to be charged 10 shown in FIGS. 1 and 2 described above.

The difference from the charging method 30 shown in FIG. 6 is that the method 40 shown in FIG. 7 further includes:

In step S402, when it is determined that electromigration has occurred between the first pole and the third pole of the first MOS transistor V1, during the charging process of the device to be charged 10, it is determined that the second pole and the third pole of the first MOS transistor V1 are being charged. Whether the sum of the first impedance between one pole and the second impedance between the second pole and the first pole of the second MOS transistor V2 is less than a preset impedance threshold.

In some embodiments, it is determined whether the sum of the first impedance between the second pole and the first pole of the first MOS transistor V1 and the second impedance between the second pole and the first pole of the second MOS transistor V2 is less than A preset impedance threshold includes: during the fast charging process of the device to be charged 10, the voltage of the first pole of the second MOS tube V2, the voltage of the first pole of the first MOS tube V1, and the charging current are respectively collected; The voltage of the first pole of the second MOS transistor V2, the voltage of the first pole of the first MOS transistor V1, and the charging current determine the sum of the first impedance and the second impedance; and determine whether the sum of the first impedance and the second impedance is less than Impedance threshold.

In some embodiments, it is determined whether the sum of the first impedance between the second pole and the first pole of the first MOS transistor V1 and the second impedance between the second pole and the first pole of the second MOS transistor V2 is less than A preset impedance threshold includes: receiving the output voltage and output current fed back by the power supply device 20 during the fast charging process of the device 10 to be charged, and collecting the voltage of the battery cell; according to the output current, output current and the voltage of the battery cell, Determine the sum of the first impedance and the second impedance; and determine whether the sum of the first impedance and the second impedance is less than the impedance threshold.

In step S404, when it is determined that the sum of the first impedance and the second impedance is less than the impedance threshold, the voltage of the third electrode of the first MOS transistor is reduced.

In some embodiments, reducing the voltage of the third pole of the first MOS transistor includes: reducing the duty cycle of the second driving signal CLK_OUT provided to the driving driving circuit 14 through the second pin Pin2; wherein, the second driving signal CLK_OUT is used to provide driving voltage for the driving circuit 14.

In some embodiments, reducing the voltage of the third pole of the first MOS transistor by the second control unit 152 includes: providing the driving circuit 14 with the first driving signal Fast_switch whose output signal is a square wave.

According to the charging method of the embodiment of the present disclosure, when the device to be charged is not connected to the power supply device, the control unit can collect and judge the source voltage of the second MOS transistor to determine whether the first MOS transistor has electromigration. . Furthermore, by judging the sum of the impedance of the drain and source of the first MOS transistor and the sum of the impedance of the drain and source of the second MOS transistor, it is determined whether the first MOS transistor has only slight electromigration, If only slight electromigration has occurred, the first MOS transistor that has undergone slight electromigration can be restored by adjusting the gate voltage of the first MOS transistor. This effectively avoids the problems of increased impedance of the fast charging path, reduced fast charging current, and even withdrawal of fast charging caused by the electromigration of the MOS tube.

Fig. 8 is a flowchart showing yet another charging method according to an exemplary embodiment. Similarly, the charging method 50 shown in FIG. 8 can be applied to the device to be charged 10 shown in FIGS. 1 and 2 described above.

Referring to FIG. 8, the charging method 50 includes:

In step S502, the first control unit 151 detects through the charging interface 11 whether there is a power supply device 20 connected to the device 10 to be charged.

In step S504, when it is detected that no power supply device 20 is connected to the device to be charged 10, the first control unit 151 sends a signal collection instruction to the second control unit 152.

In step S506, when the signal collection instruction is received, the second control unit 152 provides the first driving signal Fast_switch to the driving circuit 14 through the first pin Pin1.

In step S508, after the second control unit 152 provides the first drive signal Fast_switch to the drive circuit 14, the first control unit 151 collects the voltage of the second terminal p2 of the switch unit 13; and when the voltage of the second terminal p2 is not At zero time, it is determined that the switch unit 13 has electromigration.

In some embodiments, the method 50 further includes: after the first control unit 151 collects the first pole voltage of the second MOS transistor V2, the second control unit 152 controls the drive circuit 14 to reset through the first drive signal Fast_switch, that is, the first A driving signal Fast_switch is set to a high level.

Fig. 9 is a flowchart showing yet another charging method according to an exemplary embodiment. Similarly, the charging method 60 shown in FIG. 9 can be applied to the device to be charged 10 shown in FIGS. 1 and 2 described above.

The difference from the charging method 50 shown in FIG. 8 is that the method 60 shown in FIG. 9 further includes:

In step S602, when it is determined that electromigration has occurred between the first pole and the third pole of the first MOS transistor V1, during the fast charging process of the device 10 to be charged, the first control unit 151 sends the second control unit 152 A voltage adjustment command is sent to instruct the second control unit 152 to determine whether to reduce the voltage of the third pole of the first MOS transistor V1.

In step S604, when the voltage adjustment instruction is received, the second control unit 152 determines the first impedance between the second pole and the first pole of the first MOS transistor V1 and the second pole and the second pole of the second MOS transistor V2. Whether the sum of the second impedance between one pole is less than a preset impedance threshold.

In some embodiments, the second control unit 152 determines the first impedance between the second pole and the first pole of the first MOS transistor V1 and the second impedance between the second pole and the first pole of the second MOS transistor V2. Whether the sum of impedance is less than a preset impedance threshold includes: during the fast charging process of the device 10 to be charged, the second control unit 152 collects the voltage of the first electrode of the second MOS transistor V2 and the voltage of the first electrode of the first MOS transistor V1 respectively. The voltage and charging current of one pole; the second control unit 152 determines the first impedance and the second impedance according to the voltage of the first pole of the second MOS tube V2, the voltage of the first pole of the first MOS tube V1, and the charging current. And; and determine whether the sum of the first impedance and the second impedance is less than the impedance threshold.

In some embodiments, the second control unit 152 determines the first impedance between the second pole and the first pole of the first MOS transistor V1 and the second impedance between the second pole and the first pole of the second MOS transistor V2. Whether the sum of impedance is less than a preset impedance threshold includes: during the fast charging process of the device 10 to be charged, the second control unit 152 receives the output voltage and output current fed back by the power supply device 20, and collects the voltage of the battery unit; The current, the output current, and the voltage of the battery cell determine the sum of the first impedance and the second impedance; and determine whether the sum of the first impedance and the second impedance is less than the impedance threshold.

In step S606, when it is determined that the sum of the first impedance and the second impedance is less than the impedance threshold, the second control unit 152 lowers the voltage of the third electrode of the first MOS transistor.

In some embodiments, reducing the voltage of the third pole of the first MOS transistor by the second control unit 152 includes: reducing the duty cycle of the second driving signal CLK_OUT provided to the driving circuit 14 through the second pin Pin2; wherein , The second driving signal CLK_OUT is used to provide a driving voltage for the driving circuit 14.

According to the charging method of the embodiment of the present disclosure, when the device to be charged is not connected to the power supply device, the second control unit collects and judges the source voltage of the second MOS transistor to determine whether the first MOS transistor has occurred. Electromigration. Furthermore, by judging the sum of the impedance of the drain and source of the first MOS transistor and the sum of the impedance of the drain and source of the second MOS transistor, it is determined whether the first MOS transistor has only slight electromigration, If only slight electromigration has occurred, the first MOS transistor that has undergone slight electromigration can be restored by adjusting the gate voltage of the first MOS transistor. This effectively avoids the problems of increased impedance of the fast charging path, reduced fast charging current, and even withdrawal of fast charging caused by the electromigration of the MOS tube.

In addition, it should be noted that the above-mentioned drawings are only schematic illustrations of the processing included in the method according to the exemplary embodiment of the present disclosure, and are not intended for limitation. It is easy to understand that the processing shown in the above drawings does not indicate or limit the time sequence of these processings. In addition, it is easy to understand that these processes can be executed synchronously or asynchronously in multiple modules, for example.

The exemplary embodiments of the present disclosure are specifically shown and described above. It should be understood that the present disclosure is not limited to the detailed structure, arrangement or implementation method described herein; on the contrary, the present disclosure intends to cover various modifications and equivalent arrangements included in the spirit and scope of the appended claims.

Claims

A device to be charged is characterized in that it comprises:

Charging interface;

Battery unit

The switch unit includes a first terminal, a second terminal, and a third terminal, the first terminal is connected to the battery unit, and the second terminal is connected to the charging interface;

A driving circuit, connected to the third end of the switch unit, for driving the switch unit to turn on and off; and

The control unit is connected to the charging interface and is used to detect whether there is a power supply device connected to the device to be charged through the charging interface; when it is detected that no power supply device is connected to the device to be charged, pass The first pin provides a first drive signal to the drive circuit and collects the voltage of the second terminal of the switch unit; and when the voltage of the second terminal is not zero, it is determined that the switch unit has electromigration;

Wherein, the output level of the first driving signal is the same as the output level of the first driving signal provided to the driving circuit through the first pin when the device to be charged is charging.
The device to be charged according to claim 1, wherein the control unit comprises: a first control unit and a second control unit;

Wherein, the first control unit is connected to the charging interface, and is used to detect whether there is a power supply device connected to the device to be charged through the charging interface; and when it is detected that there is no power supply device and the waiting device When the charging device is connected, send a signal collection instruction to the second control unit;

The second control unit is respectively connected to the first control unit and the first drive circuit, and is configured to provide the drive circuit with the drive circuit through the first pin when the signal acquisition instruction is received. The first driving signal is collected, and the voltage of the second terminal of the switch unit is collected; and when the voltage of the second terminal is not zero, it is determined that the switch unit has electromigration.
The device to be charged according to claim 2, wherein the switch unit comprises: a first MOS tube and a second MOS tube, wherein the first pole of the first MOS tube passes through the first terminal and the The battery cell is connected, the first pole of the second MOS tube is connected to the charging interface through the second terminal, and the second pole of the first MOS tube is connected to the second pole of the second MOS tube. Connected, the third pole of the first MOS tube is connected to the third pole of the second MOS tube; the second control unit is used to determine the first terminal when the voltage at the second terminal is not zero Electromigration occurs between the first pole and the third pole of the MOS tube.
The device to be charged according to claim 3, wherein the second control unit is further configured to: after electromigration has occurred between the first pole and the third pole of the first MOS tube, During the charging process of the device to be charged, the first impedance between the second pole and the first pole of the first MOS tube and the second impedance between the second pole and the first pole of the second MOS tube are determined. Whether the sum of impedances is less than a preset impedance threshold; and when it is determined that the sum of the first impedance and the second impedance is less than the impedance threshold, reducing the voltage of the third electrode of the first MOS transistor.
The device to be charged according to claim 1, wherein the control unit comprises: a first control unit and a second control unit;

Wherein, the first control unit is connected to the charging interface, and is used to detect whether there is a power supply device connected to the device to be charged through the charging interface; and when it is detected that there is no power supply device and the waiting device When the charging device is connected, send a signal collection instruction to the second control unit;

The second control unit is respectively connected to the first control unit and the drive circuit, and is configured to provide the first control unit to the drive circuit through the first pin when the signal acquisition instruction is received. Drive signal

The first control unit is further configured to collect the voltage of the second terminal of the switch unit after the second control unit provides the first drive signal to the drive circuit through the first pin; and When the voltage of the second terminal is not zero, it is determined that the switch unit has electromigration.
The device to be charged according to claim 5, wherein the switch unit comprises: a first MOS tube and a second MOS tube, wherein the first pole of the first MOS tube passes through the first terminal and the The battery cell is connected, the first pole of the second MOS tube is connected to the charging interface through the second terminal, and the second pole of the first MOS tube is connected to the second pole of the second MOS tube. Connected, the third pole of the first MOS tube is connected to the third pole of the second MOS tube; the first control unit is used to determine the first terminal when the voltage at the second terminal is not zero Electromigration occurs between the first pole and the third pole of the MOS tube.
The device to be charged according to claim 6, wherein the first control unit is further configured to: after electromigration has occurred between the first pole and the third pole of the first MOS transistor, During the charging process of the device to be charged, a voltage adjustment instruction is sent to the second control unit to instruct the second control unit to determine whether to reduce the voltage of the third pole of the first MOS transistor.
The device to be charged according to claim 7, wherein the second control unit is further configured to determine the difference between the second pole and the first pole of the first MOS tube when the voltage adjustment instruction is received. Whether the sum of the first impedance between the first impedance and the second impedance between the second pole and the first pole of the second MOS transistor is less than a preset impedance threshold; and when determining the first impedance and the second impedance When the sum of impedances is less than the impedance threshold, the voltage of the third electrode of the first MOS transistor is reduced.
The device to be charged according to claim 4 or 8, wherein the second control unit is further configured to reduce the duty cycle of the second driving signal provided to the driving circuit through the second pin to Lowering the voltage of the third pole of the first MOS tube; wherein, the second driving signal is used to provide a driving voltage for the driving circuit.
The device to be charged according to claim 4 or 8, wherein the second control unit is further configured to provide the first drive signal whose output signal is a square wave to the drive circuit to reduce the first drive signal. The voltage of the third pole of a MOS tube.
The device to be charged according to claim 4 or 8, wherein the second control unit is further configured to collect the first pole of the second MOS tube during the charging process of the device to be charged. The voltage, the voltage and the charging current of the first pole of the first MOS tube, and the voltage of the first pole of the second MOS tube, the voltage of the first pole of the first MOS tube, and the charging current , Determine the sum of the first impedance and the second impedance.
The device to be charged according to claim 4 or 8, wherein the second control unit is further configured to receive the output voltage and output current fed back by the power supply device during the charging process of the device to be charged , Collect the voltage of the battery cell, and determine the sum of the first impedance and the second impedance according to the output current, the output current, and the voltage of the battery cell.
The device to be charged according to any one of claims 2-12, wherein the second control unit is further configured to pass the voltage of the first pole of the second MOS tube after the The first pin provides the first drive signal to the drive circuit to control the drive circuit to reset.
A charging method applied to a device to be charged, characterized in that the method includes:

Detecting whether a power supply device is connected to the device to be charged; and

When it is detected that the power supply device is not connected to the device to be charged, the first driving signal is provided to the driving circuit through the first pin, and the voltage of the second terminal of the switch unit is collected; and when the voltage of the second terminal is When it is not zero, it is determined that the switch unit has electromigration;

Wherein, the second end of the switch unit is connected to the charging interface of the device to be charged;

The output level of the first driving signal is the same as the output level of the first driving signal provided to the driving circuit through the first pin when the device to be charged is charging.
The method according to claim 14, wherein the switch unit comprises: a first MOS tube and a second MOS tube, wherein the first pole of the first MOS tube passes through the first end and the standby The battery unit of the charging device is connected, the first pole of the second MOS tube is connected to the charging interface through the second end, and the second pole of the first MOS tube is connected to the second pole of the second MOS tube. Two-pole connection, the third electrode of the first MOS transistor is connected to the third electrode of the second MOS transistor; determining that the switch unit has electromigration includes: determining that the first electrode of the first MOS transistor is connected to the Electromigration occurred between the third poles.
The method according to claim 15, characterized in that it further comprises:

When it is determined that electromigration has occurred between the first pole and the third pole of the first MOS tube, the second pole and the first pole of the first MOS tube are determined during the charging process of the device to be charged. Whether the sum of the first impedance between and the second impedance between the second pole and the first pole of the second MOS tube is less than a preset impedance threshold; and

When it is determined that the sum of the first impedance and the second impedance is less than the impedance threshold, the voltage of the third electrode of the first MOS transistor is reduced.
The method according to claim 16, wherein reducing the voltage of the third electrode of the first MOS tube comprises: reducing the duty cycle of the second driving signal provided to the driving circuit through the second pin ; Wherein, the second drive signal is used to provide a drive voltage for the drive circuit.
The method according to claim 16, wherein reducing the voltage of the third electrode of the first MOS transistor comprises: providing the first driving signal whose output signal is a square wave to the driving circuit.
The method of claim 16, wherein the first impedance between the second pole and the first pole of the first MOS tube and the difference between the second pole and the first pole of the second MOS tube are determined. Whether the sum of the second impedance is less than a preset impedance threshold includes:

During the charging process of the device to be charged, collecting the voltage of the first pole of the second MOS tube, the voltage of the first pole of the first MOS tube, and the charging current respectively;

Determining the sum of the first impedance and the second impedance according to the voltage of the first electrode of the second MOS tube, the voltage of the first electrode of the first MOS tube, and the charging current; and

It is determined whether the sum of the first impedance and the second impedance is less than the impedance threshold.
The method of claim 16, wherein the first impedance between the second pole and the first pole of the first MOS tube and the difference between the second pole and the first pole of the second MOS tube are determined. Whether the sum of the second impedance is less than a preset impedance threshold includes:

During the charging process of the device to be charged, receiving the output voltage and output current fed back by the power supply device, and collecting the voltage of the battery unit;

Determining the sum of the first impedance and the second impedance according to the output current, the output current, and the voltage of the battery cell; and

It is determined whether the sum of the first impedance and the second impedance is less than the impedance threshold.
The method according to any one of claims 15-20, further comprising: after collecting the first pole voltage of the second MOS transistor, providing the driving circuit through the first pin The first drive signal is used to control the drive circuit to reset.