CN113725963A

CN113725963A - Charging and discharging circuit and method with controllable voltage rising and falling, charging line and terminal equipment

Info

Publication number: CN113725963A
Application number: CN202110943882.5A
Authority: CN
Inventors: 陈佳; 刘小勇
Original assignee: Meizu Technology Co Ltd
Current assignee: Meizu Technology Co Ltd
Priority date: 2021-08-17
Filing date: 2021-08-17
Publication date: 2021-11-30

Abstract

The disclosure relates to a charging and discharging circuit and method with controllable voltage rising and falling of a battery, a charging line and terminal equipment. The circuit includes: the battery charging and discharging control system comprises a Boost circuit module, a Buck voltage reduction circuit module, a charge pump circuit module, an auxiliary voltage reduction circuit module, a battery charging and discharging control module and a system power supply module; the external alternating current-direct current adapter of input of Boost circuit module, Buck step down circuit module and charge pump circuit module, the controlled end of Boost circuit module is connected to battery charge-discharge control module, the controlled end of Buck step down circuit module, the controlled end of charge pump circuit module, the controlled end of two electric core batteries and supplementary step down circuit module, the output connection system power module of Buck step down circuit module and supplementary step down circuit module, the output of Boost circuit module, the output of charge pump circuit module and the input of supplementary step down circuit module connect two electric core batteries.

Description

Charging and discharging circuit and method with controllable voltage rising and falling, charging line and terminal equipment

Technical Field

The disclosure relates to the technical field of battery charging, in particular to a charging and discharging circuit with controllable voltage rising and falling, a method, a charging line and terminal equipment.

Background

The rechargeable battery is a rechargeable battery with limited charging times and can be matched with a charger for use. Through charging the battery, the battery can be reused, and the requirements of economy and environmental protection can be favorably met. The charging process of a battery is the reverse of its discharging process, specifically, the process of converting electrical energy into chemical energy stored in the battery.

In current terminal equipment, a single-cell battery is mainly used for charging. However, in the single cell battery, since the voltage is about 4.5V when the battery is fully charged, when the charging current exceeds 8A, the heat generation of the battery side circuit board is serious. For this reason, the battery connector is also required to be replaced with a battery connector having a smaller impedance and a larger current, which leads to an increase in hardware cost; meanwhile, the wiring and heat dissipation treatment in the battery end circuit board are also more difficult. In order to meet the heat dissipation requirement, the charging power of the battery end of a common single cell is about 36W, which results in low charging efficiency.

Disclosure of Invention

In order to solve the technical problem or at least partially solve the technical problem, the present disclosure provides a buck-boost controllable charging and discharging circuit, method, charging line and terminal device capable of improving charging efficiency.

The utility model provides a controllable charge-discharge circuit of step-up and step-down voltage for charge for two electric core batteries, the circuit includes: the battery charging and discharging control system comprises a Boost circuit module, a Buck voltage reduction circuit module, a charge pump circuit module, an auxiliary voltage reduction circuit module, a battery charging and discharging control module and a system power supply module;

the input end of the Boost circuit module, the input end of the Buck voltage reduction circuit module and the input end of the charge pump circuit module are respectively externally connected with an AC/DC adapter, the battery charge and discharge control module is connected with the controlled end of the Boost circuit module, the controlled end of the Buck voltage reduction circuit module, the controlled end of the charge pump circuit module, the double-cell battery and the controlled end of the auxiliary voltage reduction circuit module, the output end of the Buck voltage reduction circuit module and the output end of the auxiliary voltage reduction circuit module are respectively connected with the system power supply module, and the output end of the Boost circuit module, the output end of the charge pump circuit module and the input end of the auxiliary voltage reduction circuit module are respectively connected with the double-cell battery;

the battery charging and discharging control module is a control module for controlling the Boost circuit module, the Buck circuit module, the charge pump circuit module and the auxiliary Buck circuit module to work in corresponding charging and discharging stages;

the Boost circuit module works in a trickle charge stage, a constant voltage charge stage and a charge cut-off stage;

the charge pump circuit module works in a constant current charging stage and is a circuit module which enables the current output by the charge pump circuit module to be larger than the input current and enables the voltage output by the charge pump circuit module to be smaller than the input voltage;

the Buck voltage reduction circuit module works in a constant current charging stage, a constant voltage charging stage and a charging cut-off stage and is a circuit module for converting a charging voltage into a voltage suitable for a system power supply module;

the auxiliary voltage reduction circuit module works in a discharging stage and is a circuit module which converts the discharging voltage of the double-cell battery into the voltage suitable for the system power supply module.

In some embodiments, the charge pump circuit module includes N charge pump circuit sub-modules arranged in parallel; n is not less than 1 and is an integer;

the controlled ends of the N charge pump circuit sub-modules are respectively connected with the battery charge and discharge control module.

In some embodiments, the auxiliary voltage reduction circuit module includes a Buck voltage reduction circuit submodule or a charge pump circuit submodule.

In some embodiments, the Buck circuit module and the Buck circuit sub-module each include:

the Buck controller comprises a first transistor and a second transistor;

the battery information of the system power supply module is transmitted to a first charging voltage and current controller, a first transistor is connected with an output inductor in series, the input end of the first transistor is used as the input end of the Buck voltage reduction circuit module or the Buck voltage reduction circuit submodule, the output end of the output inductor is used as the output end of the Buck voltage reduction circuit module or the Buck voltage reduction circuit submodule, a first input capacitor is connected between the input end of the first transistor and the ground in series, a first output capacitor is connected between the output end of the output inductor and the ground in series, one end of a second transistor is connected between the first transistor and the output inductor, and the other end of the second transistor is grounded;

in the charging stage of the output inductor, the first transistor is switched on, and the second transistor is switched off;

in the discharging stage of the output inductor, the first transistor is turned off, and the second transistor is turned on.

In some embodiments, the charge pump circuit sub-module comprises: the first capacitor, the second capacitor, the third transistor, the fourth transistor, the fifth transistor and the sixth transistor;

the input end of the third transistor is connected with one end of a third capacitor and used as the input end of the charge pump circuit submodule, the other end of the third capacitor is grounded, the output end of the third transistor and the input end of a fourth transistor are both connected with the first end of the first capacitor, the other end of the first capacitor is connected with the input end of a sixth transistor and the output end of a fifth transistor, the output end of the sixth transistor is grounded, the output end of the fourth transistor and the input end of the fifth transistor are both connected with one end of a second capacitor and used as the output end of the charge pump circuit submodule, and the other end of the second capacitor is grounded;

in the stage of serially connecting the capacitors, the third transistor and the fifth transistor are turned on, and the fourth transistor and the sixth transistor are turned off;

in the capacitor parallel connection stage, the fourth transistor and the sixth transistor are turned on, and the third transistor and the fifth transistor are turned off.

In some embodiments, the charge pump circuit sub-module comprises: a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh transistor, an eighth transistor, a ninth transistor, a tenth transistor, an eleventh transistor, a twelfth transistor, and a thirteenth transistor;

one end of a fourth capacitor is connected with the input end of the seventh transistor and serves as the input end of the charge pump circuit submodule, the other end of the fourth capacitor is grounded, the output end of the seventh transistor and the input end of the eighth transistor are both connected with one end of the fifth capacitor, the other end of the fifth capacitor is connected with the input end of the ninth transistor and the input end of the tenth transistor, the output end of the ninth transistor and the output end of the thirteenth transistor are both grounded, the input end of the thirteenth transistor and the output end of the twelfth transistor are both connected with one end of a sixth capacitor, the other end of the sixth capacitor is connected with the output end of the tenth transistor, the output end of the eleventh transistor and the output end of the eighth transistor, the input end of the eleventh transistor and the input end of the twelfth transistor are both connected with one end of the seventh capacitor and serve as the output end of the charge pump submodule, and the other end of the seventh capacitor is grounded;

in the capacitor series connection stage, the seventh transistor, the tenth transistor and the twelfth transistor are turned on, and the eighth transistor, the ninth transistor, the eleventh transistor and the thirteenth transistor are turned off;

in the capacitor parallel connection stage, the eighth transistor, the ninth transistor, the eleventh transistor and the thirteenth transistor are turned on, and the seventh transistor, the tenth transistor and the twelfth transistor are turned off.

In some embodiments, the Boost voltage circuit module comprises: the Boost controller comprises a fourteenth transistor and a fifteenth transistor;

the battery information of the double-battery-cell battery is transmitted to the second charging voltage and current controller, the input inductor and the fourteenth transistor are connected in series between the alternating current-direct current adapter and the double-battery-cell battery, the second input capacitor is connected in series between the input end of the input inductor and the ground, the second output capacitor is connected in series between the output end of the fourteenth transistor and the ground, one end of the fifteenth transistor is connected between the fourteenth transistor and the input inductor, and the other end of the fifteenth transistor is grounded;

in the charging stage of the input inductor, the fourteenth transistor is turned off, and the fifteenth transistor is turned on;

in the discharging stage of the input inductor, the fourteenth transistor is turned on, and the fifteenth transistor is turned off.

The present disclosure also provides a buck-boost controllable charging and discharging method, which is performed based on any one of the charging and discharging circuits, and includes:

the battery charging and discharging control module collects the charging voltage and the charging current of the double-cell battery in real time and judges the charging and discharging stage of the double-cell battery based on the charging voltage and the charging current;

in the trickle charge stage, the battery charge-discharge control module controls the Boost circuit module to be opened so as to work;

in the constant-current charging stage, the battery charging and discharging control module controls the charge pump circuit module and the Buck voltage reduction circuit module to be opened to work, so that the current output by the charge pump circuit module is larger than the input current, and the voltage output by the charge pump circuit module is smaller than the input voltage;

in the constant-voltage charging stage and the charging stopping stage, the battery charging and discharging control module controls the charge pump circuit module to be closed, the Boost circuit module to be opened, and the Buck voltage reduction circuit module to be opened;

in the discharging stage, the battery charging and discharging control module controls the auxiliary voltage reduction circuit module to be opened so as to convert the discharging voltage of the double-cell battery into the voltage suitable for the system power supply module.

The present disclosure also provides a charging line, including any one of the above-mentioned charge-discharge circuits.

The present disclosure also provides a terminal device, which includes a dual-cell battery, where the dual-cell battery is charged by using any one of the above charging and discharging circuits, or by using any one of the above charging and discharging methods, or is charged based on any one of the above charging wires.

Compared with the prior art, the technical scheme provided by the embodiment of the disclosure has the following advantages:

the controllable charge-discharge circuit of step-up and step-down that this disclosed embodiment provided is a charge-discharge circuit of two electric core batteries, wherein, in the stage of charging, uses Buck step-down circuit module, for the power module power supply of system, in the stage of discharging, uses supplementary step-down circuit moduleThe system power supply module is powered, so that the system can be powered while the double-cell battery is prevented from discharging while charging, and the battery can be effectively protected; in the trickle charge, constant voltage charge and charge cut-off stage, because the current is small and the heat is less, the charge current can be controlled by using a Boost circuit module, so that the charging device is simpler and has higher flexibility; in the constant-current charging stage, the charge pump circuit module is used for controlling the charging current, so that the output current of the charge pump circuit module is larger than the input current, the current transmitted on a charging wire can be reduced when large-current charging is realized, and the charging wire has certain impedance and is based on a power calculation formula I²R, power corresponds to heating; when the current is reduced, the heat generation is also reduced, so that the heat generation on the charging wire can be reduced, and in the same way, the heat generation on the charging chip and the PCB can be reduced, namely, the overall heat generation of the charging circuit is reduced, and the higher charging efficiency is ensured.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present disclosure, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a charge and discharge circuit according to an embodiment of the disclosure;

fig. 2 is a schematic structural diagram of another charge and discharge circuit provided in the embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a connection relationship of a Buck voltage reduction circuit module in a charge and discharge circuit according to an embodiment of the disclosure;

fig. 4 is a schematic diagram of a state of an inductor in a Buck circuit module according to an embodiment of the disclosure at a charging stage;

fig. 5 is a schematic diagram of a state of an inductor in a Buck circuit module according to an embodiment of the disclosure at a discharging stage;

fig. 6 is a schematic structural diagram of a sub-module of a charge pump circuit provided in an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of the sub-module of the charge pump circuit shown in FIG. 6 in a capacitor series stage;

FIG. 8 is a schematic diagram of the sub-module of the charge pump circuit shown in FIG. 6 in a capacitor parallel stage;

fig. 9 is a schematic structural diagram of another charge pump circuit sub-module provided in the embodiment of the present disclosure;

FIG. 10 is a schematic diagram of the sub-module of the charge pump circuit shown in FIG. 9 in a capacitor series stage;

FIG. 11 is a schematic diagram of the sub-module of the charge pump circuit shown in FIG. 9 in a capacitor parallel stage;

fig. 12 is a schematic structural diagram of a connection relationship of a Boost circuit module in a charge and discharge circuit according to the embodiment of the present disclosure;

fig. 13 is a schematic diagram of a state of an inductor in a Boost circuit module according to the present disclosure at a charging stage;

fig. 14 is a schematic diagram of a state of an inductor in a Boost circuit module according to an embodiment of the disclosure at a discharging stage;

fig. 15 is a schematic flow chart of a charging and discharging method according to an embodiment of the disclosure.

010, a double-cell battery; 020. an AC/DC adapter; 110. a Boost circuit module, 120, a Buck voltage reduction circuit module; 130. a charge pump circuit module; 135. a charge pump circuit sub-module; 140. an auxiliary voltage reduction circuit module; 150. a battery charge and discharge control module; 160. a system power supply module; 201. a Buck controller; 202. a first input capacitance; 203. a first output capacitor; 204. an output inductor; 205. a first charging voltage current controller; 301. a Boost controller; 302. a second input capacitance; 303. a second output capacitor; 304. inputting an inductor; 305. a second charging voltage current controller; c1, a first capacitance; c2, a second capacitor; c3, a third capacitance; c4, a fourth capacitance; c5, a fifth capacitance; c6, a sixth capacitor; c7, a seventh capacitance; q1, a first transistor; q2, a second transistor; a Q3 third transistor; q4, a fourth transistor; q5, a fifth transistor; q6, a sixth transistor; q7, a seventh transistor; q8, an eighth transistor; q9, ninth transistor; q10, tenth transistor; q11, an eleventh transistor; q12, a twelfth transistor; q13, thirteenth transistor; q14, fourteenth transistor; q15, fifteenth transistor.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, aspects of the present disclosure will be further described below. It should be noted that the embodiments and features of the embodiments of the present disclosure may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced in other ways than those described herein; it is to be understood that the embodiments disclosed in the specification are only a few embodiments of the present disclosure, and not all embodiments.

The charging circuit of the battery provided by the embodiment of the disclosure is a charging circuit of a dual-battery cell, and comprises a Boost circuit module and a charge pump circuit module, wherein in the trickle charging, the constant voltage charging and the following charge cut-off stage, because the current is small and the heat is small, the control can be realized by using the Boost circuit module, the charging circuit is simpler and has higher flexibility; in the constant-current charging stage, the charge pump circuit module is used for controlling, so that the charging efficiency is higher and the heating is reduced when the large current is charged. Optionally, the charge pump circuit module may adopt an 1/2-time step-down charge pump (the input voltage of which is 2 times of the output voltage, and the input current of which is half of the output current), may also adopt an 1/3-time step-down charge pump (the input voltage of which is 3 times of the output voltage, and the input current of which is 1/3 of the output current), or may adopt other types of step-down charge pumps, which is not limited herein.

In addition, in the charging stage, the Buck voltage reduction circuit module can be used for supplying power to the system power supply module; the system can be powered while the double-battery-core battery is charged and discharged, so that the double-battery-core battery can be effectively protected. In the discharging stage, an auxiliary voltage reduction circuit module can be used, a Buck voltage reduction circuit submodule or a charge pump circuit submodule can be selected, the output voltage of the double-cell battery is reduced, the power supply module supplies power to the system, and the system is powered.

The charging circuit, the charging method, the charging line and the terminal device of the dual-cell battery provided by the embodiment of the disclosure are exemplarily described below with reference to fig. 1 to 15.

Fig. 1 shows a schematic structural diagram of a charge and discharge circuit provided in an embodiment of the present disclosure. Referring to fig. 1, the charge and discharge circuit is for charging the dual cell battery 010, and the charge and discharge circuit may include: the battery charging and discharging control system comprises a Boost circuit module 110, a Buck circuit module 120, a charge pump circuit module 130, an auxiliary Buck circuit module 140, a battery charging and discharging control module 150 and a system power supply module 160; the input end of the Boost circuit module 110, the input end of the Buck circuit module 120 and the input end of the charge pump circuit module 130 are respectively externally connected with an alternating current-direct current adapter 020, the battery charging and discharging control module 150 is connected with the controlled end of the Boost circuit module 110, the controlled end of the Buck circuit module 120, the controlled end of the charge pump circuit module 130, the dual-core battery 010 and the controlled end of the auxiliary Buck circuit module 140, the output end of the Buck circuit module 120 and the output end of the auxiliary Buck circuit module 140 are respectively connected with the system power supply module 160, and the output end of the Boost circuit module 110, the output end of the charge pump circuit module 130 and the input end of the auxiliary Buck circuit module 140 are respectively connected with the dual-core battery 010; the battery charging and discharging control module 150 is a control module for controlling the Boost circuit module 110, the Buck circuit module 120, the charge pump circuit module 130 and the auxiliary Buck circuit module 140 to work in corresponding charging and discharging stages; the Boost circuit module 110 operates in a trickle charge stage, a constant voltage charge stage, and a charge cut-off stage; the charge pump circuit module 130 operates in a constant current charging phase, and is a circuit module which makes the current output by the charge pump circuit module 130 greater than the input current and makes the voltage output by the charge pump circuit module 130 less than the input voltage; the Buck voltage reduction circuit module 120 operates in a constant current charging stage, a constant voltage charging stage, and a charging cut-off stage, and is a circuit module that converts a charging voltage into a voltage suitable for the system power supply module 160; the auxiliary voltage-reducing circuit module 140 operates in a discharging stage, and is a circuit module for converting the discharging voltage of the dual-cell battery 010 into a voltage suitable for the system power supply module 160. Hereinafter, the "dual cell battery" may also be simply referred to as a "battery".

In the disclosed embodiments, the charging phase of the battery may include a trickle charging phase, a constant current charging phase, a constant voltage charging phase, and a charge cutoff phase. Wherein, the trickle charge phase can be understood as a "pre-charge phase" which is a low current charge phase; the constant current charging stage is a stage of charging by adopting a constant current value, and in the stage, the charging voltage is gradually increased; the constant voltage charging stage is a stage of charging by adopting a constant voltage value, and in the stage, the charging current is gradually reduced; the charging cut-off phase, in which the charging current is smaller and smaller, corresponds to a state where the battery is fully charged when it is small to a certain extent, and corresponds to, for example, prompting the user to fully charge.

For example, in the charging phase, the circuit modules may cooperate as follows for the different phases.

In the trickle charge stage, when the voltage of the battery is lower than a certain voltage value of about 6V or 6V, the battery can be charged with a constant current of 0.1C at maximum.

Illustratively, the battery Charging and discharging control module 150 determines the Port type of the power adapter (i.e., the ac/dc adapter 020), which may include, for example, a Standard Downstream Port (SDP), a Dedicated Charging Port (DCP), or a Charging Downstream Port (CDP), or other ports known to those skilled in the art.

When the port type of the ac/dc adapter 020 is a standard downlink port SDP, it represents that the port is a pluggable USB interface on a computer, and the through-current of the port is 500mA and the voltage is 5V; when the port type of the ac/dc adapter 020 is the charging downstream port CDP, it is similar to a hub, and may be a hub with multiple interfaces, and its current is 1A-1.5A and its voltage is 5V. In both cases, the output voltage of the ac/dc adapter 020 is also 5V. The battery charge and discharge control module 150 controls: the Boost circuit module 110 is opened to work and carry out low-current charging; at this time, the charge pump circuit module 130 is turned off.

Wherein, when the port type of alternating current-direct current adapter 020 is special port DCP that charges, battery charge and discharge control module 150 also can not carry out the control agreement that steps up between the alternating current-direct current adapter 020, and alternating current-direct current adapter 020's output voltage is 5V also, and battery charge and discharge control module 150 can control: the Boost circuit module 110 is opened to work and carry out low-current charging; at this time, the charge pump circuit module 130 is also turned off.

In the constant current charging phase, when the charging voltage is greater than the set voltage threshold and the charging current is greater than the set current threshold (e.g., 1A or 2A), the battery charging and discharging control module 150 performs control: the charge pump circuit module 130 is turned on, and the battery charge and discharge control module 150 also performs a boost control protocol with the ac/dc adapter 020 to control the ac/dc adapter 020 to output a dynamic voltage and a dynamic current to the charge pump circuit module 130. At this time, the charge pump circuit module 130 will perform large-current charging, and hereinafter, the operation principle and the operation process of the charge pump circuit module 130 will be exemplarily described with reference to fig. 6 to 11; at this time, the Boost circuit module 110 is turned off, the Buck voltage-reducing circuit module 120 is continuously controlled to be turned on, and power is supplied to the system power supply module 160, so that power is supplied to the system in the charging process without affecting the charging process of the dual-cell battery 010.

In the constant-voltage charging stage and the charge cut-off stage, the charging current is smaller than the set current threshold, and the battery charge and discharge control module 150 controls the ac/dc adapter 020 to output a voltage value lower than the battery voltage, for example, 5V or 6V, without performing a boost control protocol with the ac/dc adapter 020. At this time, the battery charge and discharge control module 150 controls: turning on the Boost circuit module 110 and turning off the charge pump circuit module 130; the Buck voltage reduction circuit module 120 is continuously controlled to be turned on to supply power to the system power supply module 160, so that power is supplied to the system in the charging process without affecting the charging process of the dual-cell battery 010.

In the charging process, the voltage threshold and the current threshold may be set based on the charging requirement of the dual-cell battery, and are not limited herein.

In the discharging phase, the battery charging and discharging control module 150 controls: the auxiliary voltage reduction circuit module 140 is turned on to reduce the output voltage of the dual-battery cell 010 and supply power to the system power supply module 160; at this time, the Buck circuit block 120 and the charge pump circuit block 130 are turned off.

The system power supply module 160 mainly provides a relevant power supply for the system, so as to ensure that the system can work normally.

In the charging and discharging circuit of the dual-battery cell provided by the embodiment of the disclosure, in the trickle charging, constant voltage charging and the following charging cut-off stage, because the current is small and the heat is small, the charging and discharging circuit can be controlled by the Boost circuit module 110, and is simpler and higher in flexibility; in the constant current charging stage, the charge pump circuit module 130 is used for controlling, so that the charging efficiency is higher and the heating is reduced when the large current is charged. In addition, during the charging phase, the Buck voltage-reducing circuit module 120 may be used to supply power to the system power supply module 160; the system can be powered while the double-battery-core battery is charged and discharged, so that the double-battery-core battery can be effectively protected. In the discharging stage, the auxiliary voltage-dropping circuit module 140 may be used to drop the output voltage of the dual-cell battery 010, so as to supply power to the system power supply module 160, thereby supplying power to the system.

The specific composition and operation principle of each circuit module will be described below with reference to fig. 2 to 14.

In some embodiments, fig. 2 shows a schematic structural diagram of another charge and discharge circuit provided by the embodiments of the present disclosure, and on the basis of fig. 1, a charge pump circuit module is detailed. Referring to fig. 2, the charge pump circuit module 130 includes N charge pump circuit sub-modules 135 arranged in parallel; n is not less than 1 and is an integer; the controlled ends of the N charge pump circuit sub-modules 135 are respectively connected to the battery charge and discharge control module 150.

When the charging voltage is the same, the charging current is larger, the charging power is higher, but the heat generation is more; in order to minimize heat generation while ensuring a large charging power, i.e., to equalize charging power with heat generation, the applicable charging current range for the individual charge pump circuit sub-modules 135 may be 4A-6A.

In this way, by providing a plurality of charge pump circuit sub-modules 135 in parallel, the charge pump circuit module 130 that can be applied to a large charging current can be configured. In practical application, the number of the charge pump circuit sub-modules 135 connected in parallel can be selected according to the magnitude of the charging current, and the larger the charging current is, the larger the number of the charge pump circuit sub-modules 135 is, so that the power conversion efficiency of the whole charging scheme can be improved and the heat generation can be reduced.

For example, when the charging current is 8A-10A, the number of the charge pump circuit sub-modules 135 arranged in parallel in the charge pump circuit module 130 may be 2, and each charge pump circuit sub-module 135 shares the charging current of 4A-5A; when the charging current is 20A, the number of the charge pump circuit sub-modules 135 arranged in parallel in the charge pump circuit module 130 may be 4, and each charge pump circuit sub-module 135 shares the charging current of 5A.

It can be appreciated that the number of charge pump circuit sub-modules 135 in the charge pump circuit module 130 can also be 1.

In other embodiments, when the charging current is at other current values or in other current ranges, the number of the charge pump circuit sub-modules 135 in the charge pump circuit module 130 may be changed, and is not limited herein.

In some embodiments, the auxiliary Buck circuit module 140 includes a Buck circuit sub-module (not shown) or a charge pump circuit sub-module 135.

In the embodiment of the present disclosure, the auxiliary voltage-reducing circuit module 140 may use a Buck voltage-reducing circuit sub-module or a charge pump circuit sub-module to reduce voltage, so as to supply power to the system power supply module 160.

It will be appreciated that the Buck circuit sub-module may employ the same circuit configuration as the Buck circuit module 120, which is described in connection with fig. 3-5.

In some embodiments, fig. 3 is a schematic structural diagram illustrating a connection relationship of a Buck voltage reduction circuit module in a charge and discharge circuit in an embodiment of the present disclosure, which shows a specific structure of the Buck voltage reduction circuit module; in combination with the above, the Buck voltage reduction circuit submodule can also adopt the circuit structure, and the difference is only that the circuit modules connected with the input end and the output end of the Buck voltage reduction circuit submodule are different. On the basis of fig. 1, referring to fig. 3, the Buck circuit module 120 and the Buck circuit sub-module each include: the Buck controller 201, the first input capacitor 202, the first output capacitor 203, the output inductor 204 and the first charging voltage current controller 205, wherein the Buck controller 201 comprises a first transistor Q1 and a second transistor Q2; in the Buck circuit module 120, battery information of the system power supply module 160 is transmitted to the first charging voltage current controller 205, the first transistor Q1 and the output inductor 204 are connected in series between the ac/dc adapter 020 and the system power supply module 160, the first input capacitor 202 is connected in series between the input end of the first transistor Q1 and the ground, the first output capacitor 203 is connected in series between the output end of the output inductor 204 and the ground, one end of the second transistor Q2 is connected between the first transistor Q1 and the output inductor 204, and the other end is grounded; during the charging phase of the output inductor 204, the first transistor Q1 is turned on, and the second transistor Q2 is turned off; during the discharging phase of the output inductor 204, the first transistor Q1 is turned off and the second transistor Q2 is turned on.

It can be understood that, in the Buck voltage-reducing circuit sub-module, the first transistor Q1 and the output inductor 204 are connected in series between the dual-battery cell 010 and the system power supply module 160, and the connection relationship between other circuit components is the same as that described above and will not be described again.

Wherein, Buck circuit module 120 and Buck circuit submodule all can include Buck topological structure, also is called Buck step down circuit or Buck circuit, and this Buck circuit mainly includes: a Buck controller 201, a first input capacitor 202, a first output capacitor 203, and an output inductor 204; that is, the first input capacitor 202, the first output capacitor 203, the output inductor 204 and the Buck controller 201 form a Buck circuit; the first charging voltage current controller 205 is used to control the voltage and current that change in a sawtooth shape over time.

In the whole charging and discharging circuit, the Buck circuit is a main power supply conversion loop, so the magnitude of charging current, the charging efficiency and the heat productivity are all determined by circuit components in the Buck circuit.

The basic working principle of the Buck circuit comprises two stages as follows:

in the first Phase (Phase1), i.e., the charging Phase of the output inductor 204, with reference to fig. 4, the first transistor Q1 is turned on, the second transistor Q2 is turned off, and the output inductor 204 is charged. The first transistor Q1, the output inductor 204 and the system power supply module 160 form a main loop, and a main current of the circuit flows through the first transistor Q1, the output inductor 204 and the system power supply module 160.

In the second Phase (Phase2), i.e., the discharging Phase of the output inductor 204, referring to fig. 5, the first transistor Q1 is turned off, the second transistor Q2 is turned on, and the output inductor 204 is discharged. The second transistor Q2, the output inductor 204 and the system power supply module 160 form a main loop, and a main current of the circuit flows through the second transistor Q2, the output inductor 204 and the system power supply module 160.

In the Buck circuit, the first transistor Q1 and the second transistor Q2 have conduction loss and switching loss, and the output inductor 204 has coil loss and core loss, so that the efficiency of the entire Buck circuit cannot be high. At present, in a voltage reduction circuit generally using a Buck circuit, the conversion efficiency is below 91%. Energy lost by main power devices including the first transistor Q1, the second transistor Q2 and the output inductor 204 is basically converted into heat energy, so that the Buck circuit generates more heat when applied to a charging process, and the charging current of the whole Buck circuit cannot be large.

Based on this, in the charging and discharging circuit provided in the embodiment of the present disclosure, the Buck circuit may be adapted to convert the voltage at the input end thereof into the voltage suitable for the system power supply module 160, and is not directly converted into the current and voltage for charging the dual-cell battery 010, so as to be beneficial to avoiding excessive heat generation during the large-current charging process and avoiding affecting the charging efficiency.

In the above embodiments, the charge pump circuit sub-module may employ an 1/2-fold buck charge pump, which is described in connection with fig. 6-8; an 1/3-fold buck charge pump may also be used, as will be exemplified below in connection with fig. 9-11.

In some embodiments, fig. 6 illustrates a schematic structural diagram of a sub-module of a charge pump circuit provided in an embodiment of the present disclosure. On the basis of fig. 1, referring to fig. 6, the charge pump circuit sub-module 135 includes: a first capacitor C1, a second capacitor C2, a third capacitor C3, a third transistor Q3, a fourth transistor Q4, a fifth transistor Q5, and a sixth transistor Q6; in the charge pump circuit module 130, an input end of a third transistor Q3 and one end of a third capacitor C3 are connected to an ac/dc adapter 020, the other end of the third capacitor C3 is grounded, an output end of the third transistor Q3 and an input end of a fourth transistor Q4 are both connected to a first end of a first capacitor C1, the other end of a first capacitor C1 is connected to an input end of a sixth transistor Q6 and an output end of a fifth transistor Q5, an output end of the sixth transistor Q6 is grounded, an output end of the fourth transistor Q4, an input end of a fifth transistor Q5 and one end of a second capacitor C2 are both connected to the dual-core battery 010, and the other end of the second capacitor C2 is grounded; in the capacitor series connection stage, the third transistor Q3 and the fifth transistor Q5 are turned on, and the fourth transistor Q4 and the sixth transistor Q6 are turned off; in the capacitor parallel stage, the fourth transistor Q4 and the sixth transistor Q6 are turned on, and the third transistor Q3 and the fifth transistor Q5 are turned off.

It can be understood that, in the auxiliary voltage-reducing circuit module 140, the input terminal of the third transistor and one end of the third capacitor form the input terminal of the voltage-reducing charge pump, and are connected to the dual-cell battery; the output end of the fourth transistor, the input end of the fifth transistor and one end of the second capacitor form the output end of the step-down charge pump and are connected with the system power supply module; the connection relationship between other circuit components is the same as that described above, and is not described in detail.

In the embodiment of the present disclosure, since no inductor device is needed in the circuit structure of the charge pump circuit submodule 135, voltage reduction is realized only by switching between the turned-on capacitors, so that there is no energy loss caused by the inductor, and thus the conversion efficiency of the whole circuit structure is high.

The charge pump circuit submodule 135 in the disclosed embodiment adopts an 1/2-time step-down charge pump, the input voltage of which is 2 times of the output voltage, and the input current of which is half of the output current. The 1/2 time buck charge pump includes four transistors and three capacitors. The series and parallel connection of the capacitors to achieve voltage reduction is achieved by controlling the switching on and off of the transistors, as will be exemplarily described below with reference to fig. 7 and 8.

The basic operating principle of the 1/2-time step-down charge pump includes two stages, as follows:

in the first Phase (Phase1), i.e., the capacitor series connection Phase, or referred to as the capacitor charging Phase, as shown in fig. 7, only the third transistor Q3 and the fifth transistor Q5 are turned on, the first capacitor C1 and the second capacitor C2 are connected in series, both capacitors are charged, and the charging voltage is equal to half of the input voltage, i.e., VIN/2.

In the second Phase (Phase2), i.e., the capacitor parallel connection Phase, or referred to as the capacitor discharging Phase, as shown in fig. 8, only the fourth transistor Q4 and the sixth transistor Q6 are turned on, the first capacitor C1 and the second capacitor C2 are connected in parallel, both capacitors are discharged, and the output terminal voltage VOUT is equal to the discharging voltage across the second capacitor C2 and also equal to the charging voltage in the first Phase, i.e., VIN/2.

Thus, the pressure reduction is realized.

The circuit structure and the operation principle of the 1/2-time buck charge pump are exemplarily described above with reference to fig. 6-8, and the circuit structure and the operation principle of the 1/3-time buck charge pump are exemplarily described below with reference to fig. 9-11.

In some embodiments, fig. 9 illustrates a schematic structural diagram of another charge pump circuit sub-module provided in the embodiments of the present disclosure. Referring to fig. 9, the charge pump circuit sub-module 135 includes: a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, a seventh transistor Q7, an eighth transistor Q8, a ninth transistor Q9, a tenth transistor Q10, an eleventh transistor Q11, a twelfth transistor Q12, and a thirteenth transistor Q13; in the charge pump circuit module 130, one end of a fourth capacitor C4 and an input end of a seventh transistor Q7 are both connected to an ac/dc adaptor 020, the other end of the fourth capacitor C4 is grounded, an output end of the seventh transistor Q7 and an input end of an eighth transistor Q8 are both connected to one end of a fifth capacitor C5, the other end of a fifth capacitor C5 is connected to an input end of a ninth transistor Q9 and an input end of a tenth transistor Q10, an output end of a ninth transistor Q9 and an output end of a thirteenth transistor Q13 are both grounded, an input end of a thirteenth transistor Q13 and an output end of a twelfth transistor Q12 are both connected to one end of a sixth capacitor C6, the other end of the sixth capacitor C6 is connected to an output end of a tenth transistor Q10 and an output end of an eleventh transistor Q11, an output end of the eighth transistor Q8, an input end of the eleventh transistor Q11, an input end of the twelfth transistor Q12 and one end of the seventh capacitor C7 are both connected to the dual-core battery 010, the other end of the seventh capacitor C7 is grounded; in the capacitor series connection stage, the seventh transistor Q7, the tenth transistor Q10 and the twelfth transistor Q12 are turned on, and the eighth transistor Q8, the ninth transistor Q9, the eleventh transistor Q11 and the thirteenth transistor Q13 are turned off; in the capacitor parallel stage, the eighth transistor Q8, the ninth transistor Q9, the eleventh transistor Q11, and the thirteenth transistor Q13 are turned on, and the seventh transistor Q7, the tenth transistor Q10, and the twelfth transistor Q12 are turned off.

It can be understood that, in the auxiliary voltage-reducing circuit module 140, one end of the fourth capacitor and the input end of the seventh transistor form the input end of the voltage-reducing charge pump, and are connected to the two-cell battery; the output end of the eighth transistor, the input end of the eleventh transistor, the input end of the twelfth transistor and one end of the seventh capacitor form the output end of the step-down charge pump and are connected with the system power supply module; the connection relationship between other circuit components is the same as that described above, and is not described in detail.

The charge pump circuit submodule 135 in the disclosed embodiment adopts an 1/3-time step-down charge pump, the input voltage of which is 3 times of the output voltage, and the input current of which is 1/3 of the output current. The 1/3 times buck charge pump includes seven transistors and four capacitors. The series and parallel connection of the capacitors to achieve voltage reduction is achieved by controlling the on and off of the transistors, as will be exemplarily described below with reference to fig. 10 and 11.

The circuit working principle of the 1/3-time voltage reduction charge pump comprises two stages as follows:

in the first Phase (Phase1), which is the capacitor series Phase or capacitor charge Phase, as shown in fig. 10, the seventh transistor Q7, the tenth transistor Q10 and the twelfth transistor Q12 are all closed, i.e., turned on; the other transistors are off, i.e., turned off; at this time, the fifth capacitor C5, the sixth capacitor C6 and the seventh capacitor C7 are connected in series, and all the three capacitors are charged, and the charging voltage is equal to 1/3 of the input voltage, i.e., 1/3 VIN.

In the second Phase (Phase2), namely, the capacitor parallel connection Phase, or referred to as the capacitor discharging Phase, as shown in fig. 11, the eighth transistor Q8, the ninth transistor Q9, the eleventh transistor Q11 and the thirteenth transistor Q13 are all closed, i.e., turned on; the other transistors are off, i.e., turned off; at this time, the fifth capacitor C5, the sixth capacitor C6 and the seventh capacitor C7 are connected in parallel, the three capacitors are all discharged, and the output terminal voltage VOUT is equal to the discharge voltage across the seventh capacitor C7 and also equal to the charging voltage in the first stage, i.e., 1/3 VIN.

Thus, the pressure reduction is realized.

It can be understood that, because the input current of the 1/3 times of step-down charge pump is 1/3 of the output current, and the input current of the 1/2 times of step-down charge pump is 1/2 of the output current, under the condition that the output currents are the same, the input current corresponding to the 1/3 times of step-down charge pump is reduced 1/3 compared with the input current of the 1/2 times of step-down charge pump, thereby greatly reducing the current of the input end, further reducing the heat generation on the charging wire, the heat generation on the charging chip and the heat generation of the PCB, and ensuring higher charging efficiency. In addition, under the condition of the same input current, the output current of the 1/3-time voltage reduction charge pump is larger than that of the 1/2-time voltage reduction charge pump, namely, larger charging current can be realized, the charging efficiency is improved, and the charging time is shortened.

The circuit structure and the operation principle of the 1/2-time step-down charge pump are exemplified in conjunction with fig. 6-8, and the circuit structure and the operation principle of the 1/3-time step-down charge pump are exemplified in conjunction with fig. 9-11. In other embodiments, the charge pump circuit sub-module may also use other multiples of the buck charge pump, which is not limited herein.

The Boost circuit module is exemplarily explained below with reference to fig. 12 to 14.

In some embodiments, fig. 12 illustrates a connection relationship and a circuit structure of a Boost circuit module in a charge and discharge circuit according to an embodiment of the present disclosure. On the basis of fig. 1, referring to fig. 12, the Boost voltage circuit module 110 includes: the Boost controller 301, the second input capacitor 302, the second output capacitor 303, the input inductor 304 and the second charging voltage current controller 305, wherein the Boost controller 301 comprises a fourteenth transistor Q14 and a fifteenth transistor Q15; the battery information of the dual-cell battery 010 is transmitted to the second charging voltage current controller 305, the input inductor 304 and the fourteenth transistor Q14 are connected in series between the ac/dc adapter 020 and the dual-cell battery 010, the second input capacitor 302 is connected in series between the input end of the input inductor 304 and the ground, the second output capacitor 303 is connected in series between the output end of the fourteenth transistor Q14 and the ground, one end of the fifteenth transistor Q15 is connected between the fourteenth transistor Q14 and the input inductor 304, and the other end is grounded; during the charging phase of the input inductor 304, the fourteenth transistor Q14 is turned off, and the fifteenth transistor Q15 is turned on; during the discharging phase of the input inductor 304, the fourteenth transistor Q14 is turned on, and the fifteenth transistor Q15 is turned off.

In the embodiment of the present disclosure, the Boost circuit module 110 may include a Boost topology structure, also referred to as a Boost circuit or a Boost circuit, where the Boost circuit mainly includes: a Boost controller 301, a second input capacitor 302, a second output capacitor 303, and an input inductor 304; that is, the Boost controller 301, the second input capacitor 302, the second output capacitor 303 and the input inductor 304 form a Boost circuit; the second charge voltage current controller 305 is used to control the voltage and current that change in a sawtooth shape over time.

In the whole charging and discharging circuit, the Boost circuit is a main power supply conversion loop, so the magnitude of the charging current, the charging efficiency and the heat productivity are all determined by circuit components in the Boost circuit.

The basic working principle of the Boost circuit comprises two stages, as follows:

in the first Phase (Phase1), i.e., the charging Phase of the input inductor 304, with reference to fig. 13, the fourteenth transistor Q14 is turned off, the fifteenth transistor Q15 is turned on, and the input inductor 304 is charged. The fifteenth transistor Q15 and the input inductor 304 form a main loop, and the main current of the circuit will flow through the fifteenth transistor Q15 and the input inductor 304.

In the second Phase (Phase2), i.e., the discharging Phase of the input inductor 304, referring to fig. 14, the fourteenth transistor Q14 is turned on, the fifteenth transistor Q15 is turned off, and the input inductor 304 is discharged. The input inductor 304, the fourteenth transistor and the dual-cell battery 010 form a main circuit, and a main current of the circuit flows through the input inductor 304, the fourteenth transistor and the dual-cell battery 010.

Therefore, the charging current can be controlled by the Boost circuit module 110 in the trickle charging stage, the constant voltage charging stage and the subsequent charging cut-off stage, and the charging current is small, so that the heating is less, the control is simpler and the flexibility is higher.

In the above embodiments, the transistors in each circuit module or sub-module may be Metal-Oxide-Semiconductor Field-Effect transistors (MOSFETs) or other switching tubes known to those skilled in the art, or other types of switches may be used, and are not limited herein.

The controllable charge-discharge circuit of step-up and step-down of two electric core batteries that this disclosed embodiment provided can improve the unable bigger problem of single electric core charging power. Specifically, the charging of the double-cell battery is adopted, the charging voltage is double of that of the single-cell battery, and under the condition that the charging circuits are the same, larger charging power can be realized. For example, charging powers of 50W, 60W, 100W, or higher may be achieved.

Meanwhile, since the battery charging voltage is 2 times of the original single-cell battery voltage, the battery charging current is half of the single-cell battery current under the same battery end charging power. The heating of the circuit board at the end of the double-cell battery is obviously reduced compared with that of the single-cell battery, so that the heating is greatly reduced, and under the condition of unchanged output power, the requirement on the impedance of a battery connector is reduced due to the reduction of current, thereby being beneficial to reducing the cost; because the heat generation is reduced, the safety is favorably provided; meanwhile, the routing and heat dissipation treatment of the battery end circuit board PCB are relatively easy.

The embodiment of the disclosure also provides a charging and discharging method with controllable voltage rising and falling, which is executed based on any one of the charging and discharging circuits and has corresponding beneficial effects.

In some embodiments, fig. 15 shows a schematic flow chart of a charging and discharging method provided by the embodiments of the present disclosure. Referring to fig. 15, the method includes:

s410, the battery charging and discharging control module collects the charging voltage and the charging current of the double-cell battery in real time and judges the charging and discharging stage of the double-cell battery based on the charging voltage and the charging current.

And S420, in the trickle charge stage, the battery charge and discharge control module controls the Boost circuit module to be opened so as to work.

And S430, in the constant current charging stage, the battery charging and discharging control module controls the charge pump circuit module and the Buck voltage reduction circuit module to be opened to work, so that the current output by the charge pump circuit module is larger than the input current, and the voltage output by the charge pump circuit module is smaller than the input voltage.

And S440, in the constant-voltage charging stage and the charging ending stage, the battery charging and discharging control module controls the charge pump circuit module to be closed, the Boost circuit module to be opened, and the Buck voltage reduction circuit module to be opened.

S450, in the discharging stage, the battery charging and discharging control module controls the auxiliary voltage reduction circuit module to be opened so as to convert the discharging voltage of the double-cell battery into the voltage suitable for the system power supply module.

In the embodiment of the disclosure, the battery charging and discharging control module is used for controlling whether other circuit modules work or not so as to realize charging and discharging control. Specifically, the battery charge-discharge control module can judge the port type of the alternating current-direct current adapter so as to assist in determining a current threshold and a voltage threshold in subsequent steps and perform charge-discharge phase switching; the battery charging and discharging control module collects the charging voltage and the charging current of the dual-cell battery in real time and is used for judging whether the charging voltage is greater than a set voltage threshold value or not and whether the charging current is greater than a set current threshold value or not; if the current is greater than the preset value, the charge pump circuit module is controlled to be turned on, so that large-current charging can be performed, the charging efficiency is high, and the heat generation is less; the battery charging and discharging control module also carries out a boosting control protocol with the AC/DC adapter and controls the AC/DC adapter to output dynamic voltage and dynamic current to the charge pump circuit module so as to charge the dual-cell battery; in the discharging stage, the battery charging and discharging control module can control the auxiliary voltage reduction circuit module to reduce the output voltage of the double-cell battery so as to supply power to the system power supply module.

The embodiment of the disclosure also provides a charging wire, which comprises any one of the charging and discharging circuits.

For example, the charging and discharging circuit may be disposed at one end of the charging wire for connecting the dual-cell battery. So, can flow through undercurrent on most wire rods of charging wire to reduce generating heat on the wire rod, slow down the loss of wire rod.

The embodiment of the disclosure further provides a terminal device, which includes a dual-cell battery, wherein the dual-cell battery is charged by adopting any one of the above charging and discharging circuits, or by adopting any one of the above charging and discharging methods, or is charged based on any one of the above charging wires, so as to achieve corresponding beneficial effects.

The charging and discharging circuit can be arranged in the terminal equipment and is connected with the alternating current and direct current adapter through a charging wire. At this moment, the charging and discharging circuit is not arranged in the charging wire, so that the structure of the charging wire is simplified.

The terminal device may be, for example and without limitation, a mobile phone, a tablet, a mobile computer, or other rechargeable terminal devices known to those skilled in the art.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present disclosure, which enable those skilled in the art to understand or practice the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The utility model provides a controllable charge-discharge circuit of step-up and step-down for charge two electric core batteries, the circuit includes: the battery charging and discharging control system comprises a Boost circuit module, a Buck voltage reduction circuit module, a charge pump circuit module, an auxiliary voltage reduction circuit module, a battery charging and discharging control module and a system power supply module;

the input end of the Boost circuit module, the input end of the Buck voltage reduction circuit module and the input end of the charge pump circuit module are respectively externally connected with an AC/DC adapter, the battery charge and discharge control module is connected with the controlled end of the Boost circuit module, the controlled end of the Buck voltage reduction circuit module, the controlled end of the charge pump circuit module, a double-cell battery and the controlled end of the auxiliary voltage reduction circuit module, the output end of the Buck voltage reduction circuit module and the output end of the auxiliary voltage reduction circuit module are respectively connected with a system power supply module, and the output end of the Boost circuit module, the output end of the charge pump circuit module and the input end of the auxiliary voltage reduction circuit module are respectively connected with the double-cell battery;

the battery charging and discharging control module is a control module for controlling the Boost circuit module, the Buck voltage reduction circuit module, the charge pump circuit module and the auxiliary voltage reduction circuit module to work in corresponding charging and discharging stages;

the Buck voltage reduction circuit module works in a constant current charging stage, a constant voltage charging stage and a charging cut-off stage and is a circuit module for converting a charging voltage into a voltage suitable for the system power supply module;

the auxiliary voltage reduction circuit module works in a discharging stage and is a circuit module which converts the discharging voltage of the double-cell battery into a voltage suitable for the system power supply module.

2. The circuit of claim 1, wherein the charge pump circuit module comprises N charge pump circuit sub-modules arranged in parallel; n is not less than 1 and is an integer;

and the controlled ends of the N charge pump circuit sub-modules are respectively connected with the battery charge and discharge control module.

3. The circuit of claim 1, wherein the auxiliary voltage reduction circuit module comprises a Buck voltage circuit sub-module or a charge pump circuit sub-module.

4. The circuit of claim 3, wherein the Buck voltage-reduction circuit module and the Buck voltage-reduction circuit sub-module each comprise:

the Buck controller comprises a first transistor and a second transistor;

the battery information of the system power supply module is transmitted to the first charging voltage and current controller, the first transistor is connected in series with the output inductor, the input end of the first transistor is used as the input end of the Buck voltage reduction circuit module or the Buck voltage reduction circuit submodule, the output end of the output inductor is used as the output end of the Buck voltage reduction circuit module or the Buck voltage reduction circuit submodule, the first input capacitor is connected in series between the input end of the first transistor and the ground, the first output capacitor is connected in series between the output end of the output inductor and the ground, one end of the second transistor is connected between the first transistor and the output inductor, and the other end of the second transistor is grounded;

5. A circuit as claimed in claim 2 or 3, wherein the charge pump circuit sub-module comprises: the first capacitor, the second capacitor, the third transistor, the fourth transistor, the fifth transistor and the sixth transistor;

an input end of the third transistor and one end of the third capacitor are connected and used as an input end of the charge pump circuit sub-module, the other end of the third capacitor is grounded, an output end of the third transistor and an input end of the fourth transistor are both connected with a first end of the first capacitor, the other end of the first capacitor is connected with an input end of the sixth transistor and an output end of the fifth transistor, an output end of the sixth transistor is grounded, an output end of the fourth transistor and an input end of the fifth transistor are both connected with one end of the second capacitor and used as an output end of the charge pump circuit sub-module, and the other end of the second capacitor is grounded;

in a capacitor series connection stage, the third transistor and the fifth transistor are turned on, and the fourth transistor and the sixth transistor are turned off;

6. A circuit as claimed in claim 2 or 3, wherein the charge pump circuit sub-module comprises: a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh transistor, an eighth transistor, a ninth transistor, a tenth transistor, an eleventh transistor, a twelfth transistor, and a thirteenth transistor;

one end of the fourth capacitor is connected with the input end of the seventh transistor and serves as the input end of the sub-module of the charge pump circuit, the other end of the fourth capacitor is grounded, the output end of the seventh transistor and the input end of the eighth transistor are both connected with one end of the fifth capacitor, the other end of the fifth capacitor is connected with the input end of the ninth transistor and the input end of the tenth transistor, the output end of the ninth transistor and the output end of the thirteenth transistor are both grounded, the input end of the thirteenth transistor and the output end of the twelfth transistor are both connected with one end of the sixth capacitor, the other end of the sixth capacitor is connected with the output end of the tenth transistor and the output end of the eleventh transistor, and the output end of the eighth transistor, the input end of the eleventh transistor and the input end of the twelfth transistor are all connected with one end of the seventh capacitor, the other end of the seventh capacitor is grounded;

in a capacitor series connection stage, the seventh transistor, the tenth transistor and the twelfth transistor are turned on, and the eighth transistor, the ninth transistor, the eleventh transistor and the thirteenth transistor are turned off;

in the capacitor parallel connection stage, the eighth transistor, the ninth transistor, the eleventh transistor, and the thirteenth transistor are turned on, and the seventh transistor, the tenth transistor, and the twelfth transistor are turned off.

7. The circuit of claim 1, wherein the Boost circuit module comprises: the Boost controller comprises a fourteenth transistor and a fifteenth transistor;

the battery information of the double-battery-cell battery is transmitted to the second charging voltage and current controller, the input inductor and the fourteenth transistor are connected in series between the alternating current/direct current adapter and the double-battery-cell battery, the second input capacitor is connected in series between the input end of the input inductor and the ground, the second output capacitor is connected in series between the output end of the fourteenth transistor and the ground, one end of the fifteenth transistor is connected between the fourteenth transistor and the input inductor, and the other end of the fifteenth transistor is grounded;

in a charging phase of the input inductor, the fourteenth transistor is turned off, and the fifteenth transistor is turned on;

in a discharging phase of the input inductor, the fourteenth transistor is turned on, and the fifteenth transistor is turned off.

8. A buck-boost controllable charging and discharging method, performed by the charging and discharging circuit of any one of claims 1 to 7, the method comprising:

the battery charging and discharging control module collects the charging voltage and the charging current of the double-battery-core battery in real time and judges the charging and discharging stage of the double-battery-core battery based on the charging voltage and the charging current;

in the trickle charge stage, the battery charge and discharge control module controls the Boost circuit module to be opened so as to work;

in the constant-current charging stage, the battery charging and discharging control module controls the charge pump circuit module and the Buck voltage reduction circuit module to be opened so as to work, so that the current output by the charge pump circuit module is larger than the input current, and the voltage output by the charge pump circuit module is smaller than the input voltage;

in the constant-voltage charging stage and the charging stopping stage, the battery charging and discharging control module controls the charge pump circuit module to be closed, the Boost circuit module is opened, and the Buck voltage reduction circuit module is opened;

9. A charging cord, characterized in that it comprises a charging and discharging circuit according to any of claims 1 to 7.

10. Terminal equipment, characterized in that the terminal equipment comprises a dual-cell battery, and the dual-cell battery is charged by adopting the charging and discharging circuit of any one of claims 1 to 7, or by adopting the charging and discharging method of claim 8, or based on the charging wire of claim 9.