CN110676898B - Equipment to be charged - Google Patents

Abstract

The application discloses wait to charge equipment includes: a charging interface; a battery unit; a switching unit comprising: the first end is connected with the battery unit, and the second end is connected with the charging interface; when the switch unit is conducted, the battery unit is charged in a first charging mode by the voltage and the current input through the charging interface; stopping charging the battery unit in the first charging mode when the switch unit is turned off; the driving circuit is connected with the third end of the switch unit and used for driving the switch unit to be turned on or turned off; the control unit is connected with the driving circuit and used for providing a first driving signal for the driving circuit through a first pin of the driving circuit and controlling the driving circuit to drive the switching unit to be turned on and turned off; and is used for detecting the input voltage of the charging interface in the second charging mode through the first pin; the charging power in the first charging mode is larger than the charging power in the second charging mode.

Description

Device to be charged

technical field

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

Background technique

Devices to be charged (such as smartphones, mobile terminals or smart devices) are increasingly favored by consumers, but the devices to be charged consume a lot of power and need to be recharged frequently. It takes several hours. In order to cope with this challenge, the industry has proposed a fast charging solution to charge the device to be charged by increasing the charging power of the device to be charged.

However, in the current fast charging scheme, there is still a phenomenon of poor charging reliability, and the phenomenon of failure to charge may occur probabilistically.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known in the art to a person of ordinary skill in the art.

Contents of the invention

The disclosure provides a device to be charged, which can improve the reliability during charging.

Other features and advantages of the present disclosure will become apparent from the following detailed description, or in part, be learned by practice of the present disclosure.

According to an aspect of the present disclosure, there is provided a device to be charged, including: a charging interface; a battery unit; 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; when the switch unit is turned on, the voltage and current input through the charging interface charge the battery unit in the first charging mode; when the switch When the unit is turned off, stop charging the battery unit in the first charging mode; a drive circuit, connected to the third end of the switch unit, is used to drive the switch unit to be turned on or off; and control A unit connected to the drive circuit, configured to provide a first drive signal to the drive circuit through the first pin of the drive circuit, and control the drive circuit to drive the switch unit to be turned on and off; and used for The input voltage of the charging interface in the second charging mode is detected through the first pin; wherein, the charging power in the first charging mode is greater than the charging power in the second charging mode.

According to an embodiment of the present disclosure, the driving circuit further includes: a driving MOS transistor and a first diode; wherein, the first electrode of the driving MOS transistor is connected to the charging interface, and the control electrode passes through the first The pin is connected to the control unit, and the second pole is connected to the positive pole of the first diode; the negative pole of the first diode is grounded; The control electrode of the MOS transistor provides the first drive signal to control the drive circuit to drive the switch unit to be turned on and off.

According to an embodiment of the present disclosure, the driving circuit includes: an input circuit for the input voltage; wherein, one end of the input circuit is connected to the charging interface, and the other end is connected to the control electrode of the driving MOS transistor, and connected to the control unit through the first pin; the input voltage is provided to the battery unit through the control electrode of the drive MOS tube, so as to charge the battery unit in the second charging mode ; The control unit is used to collect the output signal of the input circuit to detect the input voltage in the second charging mode.

According to an embodiment of the present disclosure, the input circuit includes: a first resistor and a second diode; wherein, one end of the first resistor is connected to the charging interface, and the other end is connected to the second diode the anode of the second diode is connected to the control electrode of the driving MOS transistor, and is connected to the control unit through the first pin.

According to an embodiment of the present disclosure, the control unit is further configured to provide a second driving signal to the driving circuit through a third pin of the driving circuit, so as to control the driving circuit to pass the input voltage through the The input circuit is provided to the control electrode of the driving MOS transistor.

According to an embodiment of the present disclosure, the driving circuit includes: an input circuit of a clock driving signal; wherein, one end of the input circuit is connected to the control unit through the second pin of the driving circuit, and receives the control The clock driving signal provided by the unit, the other end of the input circuit is connected to the third end of the switching unit, so as to provide the voltage of the clock driving signal to the third end of the switching unit.

According to an embodiment of the present disclosure, the input circuit includes: a third diode and a fourth diode; wherein, the anode of the third diode is connected to the control unit through the second pin , the cathode is connected to the anode of the fourth diode; the cathode of the fourth diode is connected to the third end of the switch unit.

According to an embodiment of the present disclosure, the control unit includes: a single-chip microcomputer.

According to an embodiment of the present disclosure, it further includes: a detection circuit connected to the control unit; wherein, the single-chip microcomputer includes a plurality of current detection pins, temperature detection pins and impedance detection pins to control the detection circuit Carry out corresponding current, temperature and impedance detection.

According to an embodiment of the present disclosure, the control unit is further configured to control charging the battery unit with a first current value within a first time range after controlling the drive circuit to drive the switch unit to be turned on. Charging the battery unit with a second current value within the second time range thereafter, judging whether the current of the battery unit detected by the detection circuit is greater than the first current threshold, when the current of the battery unit is greater than the When the first current threshold is reached, continue to charge the battery unit with the first current value; wherein the first current value is greater than the second current value.

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, the The first pole of the second MOS transistor is connected to the charging interface through the second terminal, the second pole of the first MOS transistor is connected to the second pole of the second MOS transistor, and the first MOS transistor The control pole of the tube is connected to the control pole of the second MOS tube; the control unit is also used to control the detection circuit to detect the on-resistance of the first MOS tube and/or the second MOS tube, when When the on-resistance of the first MOS transistor and/or the second MOS transistor is greater than an impedance threshold, the driving circuit is controlled to drive the switching unit to turn off, so as to stop charging the battery unit.

According to the device to be charged provided by the embodiments of the present disclosure, the control of the fast charging mode is combined with the control of the normal charging mode. When the control unit 15 inputs the high-level first driving signal Fast_switch, it can turn on the fast charging mode; when inputting the low-level first driving signal Fast_switch, it can turn off the fast charging mode; and when collecting and detecting the input voltage, on the one hand The input voltage provided by the charging interface 11 is provided to the driving MOS transistor V5 to realize normal mode charging; on the other hand, the collected signal is reversely input to the control unit 15 to realize the detection of the input voltage provided by the charging interface 11. This design improves the reliability of the charging circuit. When fast charging is not possible, ordinary charging can also be performed through this path, thereby avoiding the phenomenon of not being able to charge.

It is to be understood that both the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present disclosure.

Description of drawings

The above and other objects, features and advantages of the present disclosure will become more apparent by describing in detail example embodiments thereof with reference to the accompanying drawings.

Fig. 1 is a block diagram of a device to be charged according to an exemplary implementation.

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

Fig. 3 is a schematic circuit diagram of a control unit according to an exemplary embodiment.

Fig. 4 is a block diagram of another device to be charged according to an exemplary embodiment.

Fig. 5 is a schematic diagram illustrating a temperature detection circuit according to an exemplary embodiment.

Detailed ways

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of example embodiments to those skilled in the art. The drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus repeated descriptions thereof will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided in order to give a thorough understanding of embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of the specific details being omitted, or other methods, components, devices, steps, etc. may be adopted. In other instances, well-known structures, methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the present disclosure.

In this disclosure, unless otherwise specified and limited, the terms "connected", "connected", and other terms should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integrated It can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediary, or an internal connection between two components or an interaction relationship between two components . Those of ordinary skill in the art can understand the specific meanings of the above terms in the present disclosure according to specific situations.

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 associated objects, indicating that there may be three types of relationships, such as A and/or B, which may indicate that A exists alone, B exists alone, and A and B exist simultaneously. The symbol "/" generally indicates that the contextual objects are an "or" relationship. The terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "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 device to be charged. It usually takes several hours to fully charge a large-capacity battery (such as a battery with a capacity of 3000 mAh) under normal charging mode. The 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 use a relatively large power (usually greater than or equal to 15W) to charge the battery in the charging device. Charge. 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 with the same capacity can be significantly shortened.

During the charging process, the power supply device (such as a power adapter, power bank, etc.) is generally connected to the device to be charged through a cable, and the power provided by the power supply device is transmitted to the device to be charged through the cable. Charging device charging.

In order to increase the charging power of the device to be charged so as to achieve the purpose of fast charging, one solution is to use a large current to charge the device to be charged. The larger the charging current, the faster the charging speed of the device to be charged. In the fast charging scheme, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor, Metal Oxide Semiconductor Field Effect Transistor, hereinafter referred to as a MOS tube) is usually set to be electrically connected to the battery in the device to be charged, through a device such as an MCU (Microcontroller Unit, micro Control unit) and other control modules to control the driving circuit electrically connected to the MOS tube to realize the conduction and shutdown of the MOS tube, thereby realizing the opening and exiting of the fast charging.

Fig. 1 is a block diagram of a device to be charged according to an exemplary implementation.

The device 10 to be charged as shown in FIG. 1 may be, for example, a terminal or a communication terminal, which includes but is not limited to being connected via a wired line, such as via a public switched telephone network (PSTN), digital digital subscriber line (DSL), digital cable, direct cable connection, and/or another data connection/network and/or via, for example, a cellular network, wireless local area network (wireless local area network, WLAN), such as a handheld digital Digital TV network of video broadcasting (digital videobroadcasting handheld, DVB-H) network, satellite network, amplitude modulation-frequency modulation (amplitude modulation-frequency modulation, AM-FM) broadcast transmitter, and/or wireless interface reception/transmission of another communication terminal A device for communicating signals. Communication terminals arranged to communicate over a wireless interface may be referred to as "wireless communication terminals", "wireless terminals" and/or "mobile terminals". Examples of mobile terminals include, but are not limited to, satellite or cellular telephones; personal communication system (PCS) terminals that may combine cellular radiotelephones with data processing, facsimile, and data communication capabilities; may include radiotelephones, pagers, Internet/ Personal Digital Assistant (PDA) with intranet access, Web browser, organizer, calendar, and/or global positioning system (GPS) receiver; and conventional laptop and/or palmtop Receiver or other electronic device including a radiotelephone transceiver. In addition, the terminal may also include, but is not limited to, devices with charging functions such as e-book readers, smart wearable devices, mobile power sources (such as charging treasures, travel chargers), electronic cigarettes, wireless mice, wireless keyboards, wireless earphones, and Bluetooth speakers. Rechargeable electronic devices.

Referring to FIG. 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 .

Wherein, 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 can 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 can also be a lightning interface, or any other type of parallel port or serial port that can be used for charging.

The battery unit 12 can be a lithium battery comprising a single lithium battery cell, or a lithium battery comprising a plurality of lithium battery cells, or the battery unit 12 can also comprise a plurality of battery cells, each battery unit comprising one or more Lithium battery cells.

For a device to be charged that contains a single battery cell, when a large charging current is used to charge a single cell, the heating phenomenon of the device to be charged is relatively serious. In order to ensure the charging speed of the equipment to be charged and alleviate the heat generation of the equipment 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, that is Directly load the voltage output by the adapter to both ends of the battery unit containing multiple cells. Compared with the single cell solution (that is, the capacity of the single cell before improvement is considered to be the same as the total capacity of multiple cells connected in series after improvement), if the same charging speed is to be achieved, the charging current required by multiple cells 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, on the premise of ensuring the same charging speed, connecting multiple cells in series can greatly reduce 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 .

When the switch unit 13 is turned on, the voltage and current input through the charging interface 11 will charge the battery unit 12 in the first charging mode; when the switch unit 13 is turned off, the battery unit 12 will be charged in the first charging mode. , that is, to exit the first charging mode. The first charging mode is, for example, the aforementioned fast charging mode.

The drive circuit 14 is used to drive the switch unit 13 to be turned on and off, so as to control the start and exit of the fast charging mode.

The control unit 15 is connected with the driving circuit 14, and is used to provide the first driving signal to the driving circuit 14 through the first pin of the driving circuit 14 (such as the pin Pin_1 in FIG. 2 ), and control the driving circuit 14 to drive the conduction of the switch unit 13. On and off; at the same time, it is also used to detect the input voltage of the charging interface 11 in the second charging mode through the first pin.

The second charging mode is, for example, the aforementioned normal charging mode, and the charging power in the first charging mode is greater than that in the second charging mode.

Taking the circuit diagram of the switch unit 13 and the drive circuit 14 shown in FIG. 2 as an example, further explain how the control unit 15 controls the opening and closing of the first charging mode through the first pin, and how to pass the first charging mode in the second charging mode. One pin detects the magnitude of the collected input voltage of the charging interface 11 .

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

Referring to FIG. 2, the switching unit 13 includes, for example, a first MOS transistor V1 and a second MOS transistor V2, wherein the first pole (such as the drain D) of the first MOS transistor V1 is connected to the battery unit 12 through the above-mentioned first terminal p1, The first electrode of the second MOS transistor V2 (such as the drain D) is connected to the charging interface 11 through the above-mentioned second terminal p2, and the second electrode of the first MOS transistor V1 (such as the source electrodes S_0~S_2) is connected to the second MOS transistor V1. The second electrode (such as source electrodes S_0 - S_2 ) of V2 is connected, and the control electrode (such as gate G) of the first MOS transistor V1 is connected to the control electrode (such as gate G) of the second MOS transistor V2 . That is, the first MOS transistor V1 and the second MOS transistor V2 are reversely connected in series.

Referring to FIG. 1 and FIG. 2 together, 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 a 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 Pin_1, and the first driving signal Fast_switch is set to a high level. At this time, the voltage of the control electrode (such as the gate G) of the driving MOS transistor V5 in the driving circuit 14 is high, and the driving MOS transistor V5 is turned on. 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 clock driving signal CLK_OUT provided by the control unit 15 to the driving circuit 14 through the pin Pin_2 is a square wave signal, which is also loaded between the diodes D1 and D2 . In order to reduce the consumption of capacitor C5 and reduce 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 and R3 is very small. The resulting pressure drop is also very small. Therefore, the superimposed voltage of the voltage VBUS and the voltage Vclk of the clock driving signal CLK_OUT can drive the first MOS transistor V1 and the second MOS transistor V2 to be turned on, that is, to drive the switch unit 13 to be turned on.

And when the first drive signal Fast_switch input by the control unit 15 through the first pin Pin_1 is set to low level, the gate voltage of the driving MOS transistor V5 is low, the driving MOS transistor V5 is turned off, and then the first MOS transistor V1 is driven. The second MOS transistor V2 is cut off, that is, the driving switch unit 13 is turned off, and the fast charging of the battery unit 12 is stopped.

In addition, as shown in Figure 2, the driving circuit 14 also includes an input circuit for the input voltage provided by the charging interface 11 composed of a resistor R6 and a diode D6, one end of the input circuit is connected to the charging interface 11, and the other end is connected to the driving MOS transistor V5 connected to the control electrode, and connected to the control unit 15 through the first pin Pin_1, the input voltage provided by the charging interface 11 is provided to the battery unit 12, so as to achieve the second charging mode (such as the above-mentioned normal charging mode). The battery unit 12 is charged. Moreover, in the second charging mode, the control unit 15 is also used to collect the output signal of the input circuit to detect the magnitude of the input voltage provided by the charging interface 11 in the second charging mode. The diode D6 can form a loop with the input voltage VBUS provided by the charging interface 11 when the first driving signal Fast_switch is at a low level to discharge the overcharging current, thereby improving the charging stability. At the same time, this circuit is also conducive to heat dissipation, which can improve the problem of high-temperature and low-temperature storage work.

According to the device to be charged provided by the embodiments of the present disclosure, the control of the fast charging mode is combined with the control of the normal charging mode. When the control unit 15 inputs the high-level first driving signal Fast_switch, it can turn on the fast charging mode; when inputting the low-level first driving signal Fast_switch, it can turn off the fast charging mode; and when collecting and detecting the input voltage, on the one hand The input voltage provided by the charging interface 11 is provided to the driving MOS transistor V5 to realize normal mode charging; on the other hand, the collected signal is reversely input to the control unit 15 to realize the detection of the input voltage provided by the charging interface 11. This design improves the reliability of the charging circuit. When fast charging is not possible, ordinary charging can also be performed through this path, thereby avoiding the phenomenon of not being able to charge.

It should be clearly understood that this disclosure describes how to make and use specific examples, but that the principles of the disclosure are not limited to any details of these examples. Rather, these principles can be applied to many other implementations based on the teachings of the present disclosure.

In some embodiments, the second pole of the driving MOS transistor V5 (the source as shown in FIG. 2 ) can also be grounded through the diode D5. The anode of the diode D5 is connected to the second pole of the driving MOS transistor, and the cathode is grounded. This connection method can form a loop, prevent the voltage from being poured back into the chip, and cause damage to the chip, and further improve the reliability of charging. In addition, the setting of the diode D5 can also simultaneously improve the problem of high temperature and low temperature storage work.

In some embodiments, as shown in FIG. 2 , the control unit 15 can also be used to provide the second driving signal VOOC_MOS_G through the third pin Pin_3 of the driving circuit 14 to control the driving circuit 14 to provide the input voltage VBUS provided by the charging interface 11 Provided to the control electrode of the driving MOS transistor V5. The setting of this control bit can stably detect the voltage of the control electrode of the drive MOS tube, ensure stable charging, solve the problem of not being able to charge, and also improve the problem of intermittent charging.

In some embodiments, the resistor R2 connected between the control electrodes of the first MOS transistor V1 and the second MOS transistor V2 and the ground can also adjust the magnification through the design of its resistance value, and adjust the driving MOS transistor V5 to control pole current, thereby regulating the output voltage provided to the battery cell 12.

In some embodiments, as shown in FIG. 2 , the driving circuit 15 further includes: an input circuit for the clock driving signal CLK_OUT composed of capacitors C2 , C3 , C4 and diodes D2 , D3 , D4 . One end of the input circuit is connected to the control unit 15 through the second pin Pin_2 of the drive circuit 14, and receives the clock drive signal CLK_OUT provided by the control unit 15; the other end is connected to the third end p3 of the switch unit 13 to transmit the clock drive signal The voltage of CLK_OUT is provided to the third terminal p3 of the switch unit 13 , that is, to the gate electrodes of the first MOS transistor V1 and the second MOS transistor V2 . Among them, the diodes D3 and D4 ensure the unidirectional conduction of the circuit, and prevent the current from being poured into the control unit 15 due to the inconsistency of the start-up sequence of the device to be charged, causing damage to the control unit 15 . At the same time, the high-level voltage drop of the clock driving signal CLK_OUT can be reduced to improve charging reliability. In addition, the diode also has temperature characteristics, which can compensate for some high and low temperature changes and improve the problem of high temperature and low temperature storage work.

Fig. 3 is a schematic circuit diagram of a control unit according to an exemplary embodiment.

Referring to FIG. 3 , the control unit 15 further includes a microcontroller U1. The single-chip microcomputer has more input/output (I/O) interfaces, and can provide more control bits, thereby providing more control functions for other modules in the charging device. In addition, the signal acquisition of the single-chip microcomputer is also more convenient and the processing speed is faster.

Fig. 4 is a block diagram of another device to be charged according to an exemplary embodiment.

Different from the device to be charged 10 shown in FIG. 1 , the device to be charged 30 further includes: a detection circuit 16 . The detection circuit 16 is connected to the control unit 15 . Referring to Figure 3 and Figure 4 together, the single chip microcomputer U1 also includes multiple current detection pins (such as pin P_2 providing VBAT_ADC signal, pin P_3 providing VBUS_ADC control signal and pin P_4 providing Vfb signal), temperature detection pin (such as pin P_5 providing TEM3_ACD signal) and impedance detection pin (such as pin P_6 providing TEM2_ACD signal). The control unit 15 can control the detection circuit 16 to perform corresponding current detection, temperature detection and impedance detection through these pins. For example, the VBAT_ADC signal can be used to control the detection of the battery current, and the VBUS_ADC can be used to control the detection of the input current provided by the charging interface 11 . In addition, a thermistor can also be used for temperature detection, making the detection rate faster. Fig. 5 is a schematic diagram illustrating a temperature detection circuit according to an exemplary embodiment. As shown in FIG. 5 , the temperature detection circuit may include a thermistor Rt for temperature detection.

In some embodiments, the control unit 15 is also used to control the charging of the battery unit 12 with the first current value within the first time range after the control drive circuit 14 drives the switch unit 13 to conduct (that is, when the fast charging starts). , charge the battery unit with the second current value within the second time range thereafter, and judge whether the current of the battery unit 12 detected by the detection circuit 16 is greater than the first current threshold, thereby judging whether the device 10 to be charged can perform fast charging Or it is judged whether there is a problem of intermittent charging in the device 10 to be charged. When the current of the battery unit 12 is greater than the first current threshold, the battery unit 12 continues to be charged at the first current value. Wherein, the first current value is greater than the second current value. It should be noted that the settings of the above parameters can be set according to actual requirements in the application, and the present disclosure is not limited thereto.

In addition, because the first MOS transistor V1 and the second MOS transistor V2 in the switch unit 13 have gate-source leakage and low gate voltage, the conduction of the first MOS transistor V1 and the second MOS transistor V2 is not complete. , the problem of large on-resistance. In some embodiments, the control unit 15 can also be used to control the detection circuit 16 to detect the on-resistance of the first MOS transistor V1 and/or the second MOS transistor V2. When the on-resistance of the first MOS transistor V1 and/or the second MOS transistor V2 is greater than the impedance threshold, the control drive circuit 14 drives the switch unit 13 to turn off, so as to stop charging the battery unit 12 . In order to solve the above-mentioned problem that the on-resistance becomes larger, the impedance threshold can be set to a higher value, so that the battery unit 12 can also be charged in this case. Due to the large on-resistance, continuous charging will heat up the first MOS transistor V1 and/or the second MOS transistor, thereby improving the electromigration problem of the first MOS transistor V1 and/or the second MOS transistor.

Exemplary embodiments of the present disclosure have been specifically shown and described above. It should be understood that the disclosure is not limited to the detailed structures, arrangements or methods of implementation described herein; on the contrary, the disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims (10)

1. A device to be charged, comprising: charging interface; battery unit; A switch unit, including: 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; when the switch unit is turned on, Charging the battery unit in a first charging mode through the voltage and current input through the charging interface; when the switch unit is turned off, stopping charging the battery unit in the first charging mode; a driving circuit, connected to the third end of the switch unit, for driving the switch unit to be turned on or off; and a control unit connected to the drive circuit, configured to provide a first drive signal to the drive circuit through the first pin of the drive circuit, and control the drive circuit to drive the switch unit to be turned on and off; and for detecting the input voltage of the charging interface in the second charging mode through the first pin; Wherein, the charging power in the first charging mode is greater than the charging power in the second charging mode; The driving circuit further includes: a driving MOS transistor and a first diode; wherein, the first pole of the driving MOS transistor is connected to the charging interface, and the control pole is connected to the control unit through the first pin , the second pole is connected to the positive pole of the first diode; the negative pole of the first diode is grounded; the control unit provides the control pole of the drive MOS tube with the The first driving signal controls the driving circuit to drive the switch unit to be turned on and off. 2. The device to be charged according to claim 1, wherein the driving circuit comprises: an input circuit for the input voltage; wherein, one end of the input circuit is connected to the charging interface, and the other end is connected to the charging interface. The control electrode of the driving MOS transistor is connected, and is connected to the control unit through the first pin; the input voltage is provided to the battery unit through the controlling electrode of the driving MOS transistor, so that in the second Charging the battery unit in the charging mode; the control unit is used to collect the output signal of the input circuit to detect the input voltage in the second charging mode. 3. The device to be charged according to claim 2, wherein the input circuit comprises: a first resistor and a second diode; wherein, one end of the first resistor is connected to the charging interface, and the other is One end is connected to the anode of the second diode; the cathode of the second diode is connected to the control electrode of the driving MOS transistor, and is connected to the control unit through the first pin. 4. The device to be charged according to claim 2 or 3, wherein the control unit is further configured to provide a second drive signal to the drive circuit through a third pin of the drive circuit to control the The driving circuit provides the input voltage to the control electrode of the driving MOS transistor through the input circuit. 5. The device to be charged according to claim 1, wherein the drive circuit comprises: an input circuit of a clock drive signal; wherein, one end of the input circuit is connected to the second pin of the drive circuit with the The control unit is connected to receive the clock drive signal provided by the control unit, and the other end of the input circuit is connected to the third end of the switch unit to provide the voltage of the clock drive signal to the switch unit. third end. 6. The device to be charged according to claim 5, wherein the input circuit comprises: a third diode and a fourth diode; wherein, the anode of the third diode passes through the first diode The second pin is connected to the control unit, and the cathode is connected to the anode of the fourth diode; the cathode of the fourth diode is connected to the third terminal of the switch unit. 7. The device to be charged according to claim 1, wherein the control unit comprises: a single chip microcomputer. 8. The device to be charged according to claim 7, further comprising: a detection circuit connected to the control unit; wherein the single-chip microcomputer includes a plurality of current detection pins, temperature detection pins and impedance detection pins pins to control the detection circuit to perform corresponding current, temperature and impedance detection. 9. The device to be charged according to claim 8, characterized in that, the control unit is further configured to, after controlling the drive circuit to drive the switch unit to be turned on, to control the charging with the first current within the first time range value to charge the battery unit, charge the battery unit with the second current value within the second time range thereafter, and judge whether the current of the battery unit detected by the detection circuit is greater than the first current threshold, when When the current of the battery unit is greater than the first current threshold, continue to charge the battery unit with the first current value; wherein the first current value is greater than the second current value. 10. The device to be charged according to claim 8, wherein the switch unit comprises: a first MOS transistor and a second MOS transistor; wherein the first pole of the first MOS transistor passes through the first terminal Connected to the battery unit, the first pole of the second MOS tube is connected to the charging interface through the second end, the second pole of the first MOS tube is connected to the first pole of the second MOS tube Diode connection, the control pole of the first MOS transistor is connected to the control pole of the second MOS transistor; the control unit is also used to control the detection circuit to detect the first MOS transistor and/or the second MOS transistor The on-resistance of the two MOS transistors, when the on-resistance of the first MOS transistor and/or the second MOS transistor is greater than the impedance threshold, the driving circuit is controlled to drive the switching unit to turn off, so as to stop the The battery unit is charged.

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