CN216819411U

CN216819411U - Charging box and circuit thereof, and wireless earphone assembly

Info

Publication number: CN216819411U
Application number: CN202122041372.7U
Authority: CN
Inventors: 王钊
Original assignee: Zgmicro Corp
Current assignee: Zgmicro Corp
Priority date: 2021-08-27
Filing date: 2021-08-27
Publication date: 2022-06-24
Anticipated expiration: 2031-08-27

Abstract

The utility model relates to a charging box, a circuit of the charging box and a wireless earphone assembly. The circuit comprises a battery and a charging and power supplying unit, wherein the charging and power supplying unit comprises a controller, an inductor, a plurality of switching devices, a voltage input end, a battery end and a voltage output end, and one end of the battery is grounded while the other end is coupled with the battery end; the controller controls the on and off of the plurality of switching devices to enable the charging and power supplying unit to work in a first mode or a second mode, the charging voltage can be generated based on the voltage input by the voltage input end and the inductance in the first mode and is output to the battery through the battery end, and meanwhile, the voltage input by the voltage input end can be output to the wireless earphone through the voltage output end; in the second mode, the output voltage can be generated based on the battery and the inductor and is output to the wireless earphone through the voltage output end; the output voltage can provide a charging voltage for the earphone battery. The utility model has the advantages of high charging speed, small heating, no need of increasing inductance, simplified circuit structure and shortened charging time of the earphone.

Description

Charging box and circuit thereof, and wireless earphone assembly

Technical Field

The utility model relates to the technical field of earphones, in particular to a charging box and a circuit thereof, and a wireless earphone assembly.

Background

Compared with wired earphones, wireless earphones have the advantage of being convenient to carry, and are therefore increasingly popular with people. The Wireless headset may be a True Wireless Stereo (TWS) headset. In the conventional design, a charging management unit in a charging box of a wireless headset is generally a linear charging circuit, and the charging management unit has the defects of low charging speed and high heat generation. One way to improve this is to replace it with a switch-type charging circuit, but the switch-type charging circuit requires an additional inductor, which increases the cost and occupies a larger space. In addition, when the battery of the charging box is dead, the battery of the charging box needs to be charged firstly, and then the battery of the charging box needs to be charged for the wireless earphone, so that the charging time of the wireless earphone is long, and the circuit structure is complex.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to overcome the above-mentioned problems, and an object of the present invention is to provide a charging box, a circuit thereof, and a wireless earphone assembly, which have the advantages of fast charging speed, low heat generation, no need of increasing inductance, and capability of shortening the charging time of an earphone and simplifying the circuit structure when the battery of the charging box is dead or insufficient.

In order to achieve the above object, an aspect of the present invention provides a charging box circuit, which includes a charging box battery and a charging and supplying unit, where the charging and supplying unit includes a controller, an inductor, a plurality of switching devices, a voltage input terminal, a battery terminal, and at least one voltage output terminal, one terminal of the charging box battery is coupled to a first ground terminal, and the other terminal of the charging box battery is coupled to the battery terminal of the charging and supplying unit; the controller is configured to control on and off of the plurality of switching devices, so that the charging and power supplying unit operates in a first mode or a second mode, and the time-division multiplexing of the inductor is implemented, where: when the voltage input by the voltage input end is greater than or equal to a first reference voltage, the charging and power supplying unit works in the first mode, the charging and power supplying unit can generate a charging voltage based on the voltage input by the voltage input end and the inductor, and the charging voltage is output to the charging box battery through the battery end, so that the switch charging is realized, and meanwhile, the charging and power supplying unit can output the voltage input by the voltage input end to the wireless earphone through the voltage output end; when the voltage input by the voltage input end is less than a first reference voltage and the voltage of the charging box battery is greater than the effective output voltage of the charging box battery, the charging and power supplying unit works in the second mode, the charging and power supplying unit can generate output voltage based on the charging box battery and the inductor, the output voltage is output to the wireless earphone through the voltage output end, the output voltage can provide charging voltage for the wireless earphone battery, and the switch power supply is achieved.

Optionally, the first connection end of the inductor is coupled to the charging box battery, the charging box circuit further includes a third capacitor, one end of the third capacitor is coupled to the first connection end of the inductor, and the other end of the third capacitor is grounded, in the first mode, the controller is configured to control the plurality of switching devices to be turned on and off, so that the second connection end of the inductor is alternately coupled to the voltage input end and the first ground end, and when the second connection end of the inductor is coupled to the voltage input end, the second connection end of the inductor is simultaneously coupled to the at least one voltage output end; in the second mode, the controller is configured to control the plurality of switching devices to be turned on and off, such that the second connection terminal of the inductor is alternately coupled to one of the at least one voltage output terminal and the first ground terminal.

Optionally, the first connection terminal of the inductor is coupled to a first node N1, the second connection terminal of the inductor is coupled to a second node N2, the plurality of switching devices includes a third switch and a fourth switch, the third switch is coupled between the voltage input terminal and the second node N2, and the fourth switch is coupled between the second node N2 and the first ground terminal; the at least one voltage output terminal includes: a first voltage output terminal, the plurality of switching devices further comprising a first switch coupled between the first voltage output terminal and the second node N2; and/or a second voltage output terminal, the plurality of switching devices further comprising a second switch coupled between the second voltage output terminal and the second node N2.

Optionally, in the first mode, the controller is configured to control the third switch and the fourth switch to be turned on alternately, and when the third switch is turned on, at least one of the first switch and the second switch is turned on; or, in the second mode, the controller is configured to control the third switch to be continuously turned off, and to alternately perform a first sub-mode and a second sub-mode, in the first sub-mode, the controller is configured to control the fourth switch and the first switch to be alternately turned on, and in the second sub-mode, the controller is configured to control the fourth switch and the second switch to be alternately turned on.

Optionally, the charging and power supplying unit includes a first comparator, a first input terminal of the first comparator is coupled to the voltage input terminal, a second input terminal of the first comparator inputs the first reference voltage, an output terminal of the first comparator is connected to the controller, and the controller determines, according to a result output by the output terminal of the first comparator, whether the charging and power supplying unit can operate in the first mode; the charging and power supplying unit comprises a second comparator, a first input end of the second comparator is coupled with the charging box battery, a second reference voltage is input to a second input end of the second comparator, the second reference voltage is larger than or equal to the effective output voltage, an output end of the second comparator is connected with the controller, and the controller judges whether the charging and power supplying unit can work in the second mode according to results output by output ends of the first comparator and the second comparator.

Optionally, the output voltage can be representative of data information when a charging box needs to communicate with the wireless headset.

Optionally, the data information is binary data represented by 1 and 0, wherein: the output voltage comprises a high level voltage and a low level voltage, the high level voltage represents a logic 1, and the low level voltage represents a logic 0; or the output voltage represents logic 1 for a first duration, and the output voltage represents logic 0 for a second duration; or, the output voltage comprises a high-level voltage and a low-level voltage, the period of alternation of the high-level voltage and the low-level voltage is greater than the set time length and represents one of logic 1 and 0, and the period of alternation of the high-level voltage and the low-level voltage is less than the set time length and represents the other of logic 1 and 0.

Optionally, in the first mode, the controller is further configured to sample a charging current, and control on and off duty ratios of the plurality of switching devices according to the sampled charging current, so as to implement constant-current charging control on the charging box battery; in the first mode, the controller is further configured to sample a charging voltage and control on and off duty ratios of the plurality of switching devices according to the sampled charging voltage, so as to realize constant-voltage charging control of the charging box battery; in the second mode, the controller is further configured to sample an output voltage at the at least one voltage output terminal, and control the output voltage by controlling duty ratios of on and off of the plurality of switching devices according to the sampled output voltage; and/or the at least one voltage output end comprises a first voltage output end and a second voltage output end, and a first output capacitor is arranged between the first voltage output end and the ground in series; a second output capacitor is arranged between the second voltage output end and the ground in series; in the second mode, the controller controls the charging and power supplying unit to generate an output voltage based on the voltage output from the charging box battery and the inductor and alternately output through the first voltage output terminal and the second voltage output terminal.

A second aspect of the present invention provides a charging box comprising the charging box circuit of the first aspect described above.

A third aspect of the present invention provides a wireless headset assembly comprising: a wireless earphone having a voltage connection terminal and a second ground terminal and including an earphone battery; in the charging box provided by the second aspect, when charging, the first ground terminal of the charging box is coupled to the second ground terminal, and the voltage output terminal of the charging box is coupled to the voltage connection terminal, so that the voltage connection terminal can receive the output voltage output by the voltage output terminal, and the output voltage can charge the earphone battery.

In the scheme, the charging management circuit in the charging box circuit is replaced by the switch-type charging circuit from the linear charging circuit, and the switch-type charging circuit and the voltage regulating circuit are integrated into the charging and power supply unit, so that the switch-type charging management circuit and the voltage regulating circuit share the inductor, and the advantages of the switch-type charging circuit in charging the battery of the charging box can be realized, namely, the charging speed is high, the heating is small, and the inductor is not required to be additionally added, so that the space can be saved, the cost is reduced, and the miniaturization is favorably realized; further, when the battery of the charging box is not charged or the electric quantity is insufficient, the voltage input by the voltage input end can be utilized to charge the wireless earphone while the battery of the charging box is charged, the charging time of the wireless earphone is shortened, the structure of the circuit of the charging box is simplified, the area of a chip bearing the circuit of the charging box is smaller, and the miniaturization is favorably realized.

Additional features and advantages of the utility model will be set forth in the detailed description which follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a charging circuit of a wireless headset assembly;

fig. 2 is a schematic structural diagram of a charging box circuit according to an embodiment of the present disclosure;

fig. 3 is a schematic circuit structure diagram of the charging and power supplying unit in fig. 2;

fig. 4 is an exemplary waveform of the current in the inductor and the waveform of the switch control signal when the charging and power supplying unit is in the step-down charging state;

fig. 5 is an exemplary waveform of the current in the inductor and the waveform of the switch control signal when the charging and power supplying unit is in the boost power supplying state;

fig. 6 is a schematic structural diagram of a charging circuit of a wireless headset assembly according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

Fig. 1 is a schematic structural diagram of a charging circuit of a wireless headset assembly. Wherein, the wireless earphone component can comprise a charging box and a wireless earphone. As shown in fig. 1, the charging circuit consists of two parts, namely a first part located in the charging box (as shown in the left dashed box in fig. 1) and a second part located in the wireless headset (as shown in the right dashed box in fig. 1). The first partial circuit may include a charge box battery BAT2, a linear charging circuit, and a voltage boosting circuit. The second part of the circuit may comprise a headset battery BAT1 and a charge management circuit, and may further comprise a voltage regulation circuit DCDC, an application processor AP and a radio frequency circuit RF 1.

The linear charging circuit in the charging box realizes the function of charging the battery BAT2 of the charging box, the function of the booster circuit is to provide the voltage output by the battery BAT2 of the charging box to the wireless earphone after being boosted to 5V, namely, the voltage of VCHG is 5V voltage, and the charging management circuit in the wireless earphone charges the battery VBAT1 of the earphone through the 5V voltage. The voltage regulating circuit DCDC can adjust the voltage of the earphone battery BAT1 to the voltage required by the application processor AP and the radio frequency circuit RF1, and then the voltage is respectively output to the application processor AP and the radio frequency circuit RF1, and the radio frequency circuit RF1 can communicate with terminal equipment such as a mobile phone.

In the above scheme, the linear charging circuit in the charging box has the problems of low charging speed and large heat generation during charging. One way to improve this is to replace it with a switch-type charging circuit, but the switch-type charging circuit requires an additional inductor, which increases the cost and occupies a larger space. In addition, when the battery of the charging box is dead, the battery of the charging box needs to be charged firstly, and then the battery of the charging box needs to be charged for the wireless earphone, so that the charging time of the wireless earphone is long, and the circuit structure is complex.

In view of this, the embodiment of the present application provides a charging box, a circuit thereof, and a wireless headset assembly, which have the advantages of fast charging speed, low heat generation, no need of increasing an inductor, and capability of shortening a charging time of a headset and simplifying a circuit structure when a battery of the charging box is dead or insufficient in electric quantity.

Fig. 2 is a schematic structural diagram of a charging box circuit according to an embodiment of the present application. As shown in fig. 2, the charging box circuit includes a charging box battery BAT2 and a charging and power supply unit 21, and the charging and power supply unit 21 may include a voltage input terminal VIN, a battery terminal, and at least one voltage output terminal VO1 and/or VO 2. One end of the battery BAT2 is coupled to the first ground terminal, and the other end is coupled to the battery terminal of the charging and power supplying unit 21.

Compared with fig. 1, fig. 2 adopts a charging and power supplying unit 21 instead of the linear charging circuit and the boosting circuit in fig. 1. That is, the principle of the present invention is to replace the linear charging circuit in the charging box circuit with the switch-type charging circuit, and integrate the switch-type charging circuit and the voltage boost circuit (i.e., the voltage regulation circuit) into the charging and power supplying unit 21, so that the switch-type charging management circuit and the voltage regulation circuit share the inductor, which can achieve the advantages of the switch-type charging circuit in charging the battery BAT2 in the charging box, i.e., the charging speed is fast, the heat generation is small, and the inductor L1 is not required to be additionally added, thereby saving space, reducing cost, and facilitating the miniaturization.

Fig. 3 is a schematic circuit diagram of the charging and power supplying unit in fig. 2. As shown in fig. 3, the charging and power supplying unit 21 may further include a controller Ctrl, an inductor L1, and a plurality of switching devices such as S1-S4. The controller Ctrl is configured to control on and off of the plurality of switching devices, so that the charging and power supplying unit 21 operates in the first mode or the second mode, and the time-division multiplexing inductor L1 is implemented.

When the voltage input by the voltage input terminal VIN is greater than or equal to the first reference voltage, the charging and supplying unit 21 operates in the first mode, the charging and supplying unit 21 can generate a charging voltage based on the voltage input by the voltage input terminal VIN and the inductor L1, and output the charging voltage to the battery BAT2 of the charging box through the battery terminal, so as to realize switch charging, and meanwhile, the charging and supplying unit 21 can output the voltage input by the voltage input terminal VIN to the wireless headset through the voltage output terminals, such as VO1 and VO 2. Like this, when the box battery BAT2 that charges does not have electricity or the electric quantity is not enough, can utilize the voltage of voltage input VIN input to charge for wireless earphone when charging box battery BAT2, shortened wireless earphone's charge time to the structure of the box circuit that charges has been simplified, make the area of bearing the chip of the box circuit that charges less, be favorable to realizing the miniaturization.

When the voltage input by the voltage input terminal VIN is less than the first reference voltage and the voltage of the battery BAT2 of the charging box is greater than the effective output voltage, the charging and supplying unit 21 works in the second mode, and the charging and supplying unit 21 can generate an output voltage based on the battery BAT2 of the charging box and the inductor L1, and output the output voltage to the wireless headset through a voltage output terminal such as VO1 or VO 2. The output voltage can provide charging voltage for the wireless earphone battery, and the switch power supply is realized.

In addition, the output voltage can represent data information when the charging box needs to communicate with the wireless headset. The output voltage may be representative of data information so that the charging box may communicate with the wireless headset. In particular, the communication function may be performed simultaneously with the switch power supply, or separately. That is, the output voltage output by the charging box circuit through the voltage output end can be only used for supplying power to the wireless earphone, and only the switch power supply is realized; or the output voltage output by the charging box circuit through the voltage output end can be only used for representing data information to realize the communication between the charging box and the wireless earphone, and at the moment, the charging box circuit can not be used for charging the wireless earphone and only realizes the communication function; or the output voltage output by the charging box circuit through the voltage output end is used for supplying power to the wireless earphone, and meanwhile, the output voltage can also be used for representing data information, so that the communication between the charging box and the wireless earphone is realized, namely, the communication function is realized while the switch is used for supplying power.

The data information may include the power of the battery BAT2 of the charging box, the on-off state of the lid of the charging box, and other information. The data information may be binary data represented by 1 and 0, and the output voltage may include a high level voltage representing a logic 1 and a low level voltage representing a logic 0. Alternatively, the duration of the output voltage for the first time period may represent a logic 1, and the duration of the output voltage for the second time period may represent a logic 0. Alternatively, the output voltage may include a high level voltage and a low level voltage, the period of alternation of the high level voltage and the low level voltage is greater than the set time period representing one of logic 1 and 0, and the period of alternation of the high level voltage and the low level voltage is less than the set time period representing the other of logic 1 and 0.

It should be noted that, generally, the voltage that the battery BAT2 of the charging box can charge the earphone battery needs to be higher than a certain voltage threshold, for example, the discharging voltage of the lithium battery is 0-4.2V, but the voltage that can charge the earphone battery is generally more than 3V, so the voltage that can charge the earphone battery is defined as the effective output voltage of the battery BAT2 of the charging box.

As shown in fig. 3, to implement the first mode operation, the charging and supplying unit 21 may include a first comparator Com1, a first input terminal of the first comparator Com1 is coupled to the voltage input terminal VIN, a second input terminal of the first comparator Com1 inputs a first reference voltage VR1, an output terminal of the first comparator Com1 is connected to the controller Ctrl, and the controller Ctrl determines whether the charging and supplying unit 21 can operate in the first mode according to a result output by an output terminal of the first comparator Com 1. Further, in the first mode, the controller Ctrl may be further configured to sample the charging current and control on and off duty ratios of the plurality of switching devices according to the sampled charging current, so as to implement constant-current charging control on the charging box battery BAT 2. In the first mode, the controller Ctrl may be further configured to sample the charging voltage, and control the on and off duty ratios of the plurality of switching devices according to the sampled charging voltage, thereby implementing constant-voltage charging control on the battery BAT2 of the charging box. In one example, the controller Ctrl may sample the voltage across the third switch S3 and combine with the resistance of the third switch S3 to obtain the charging current. The voltage at one side of the third switch S3 is the voltage at the voltage input terminal VIN. The charging voltage is the voltage VBAT2 at the battery terminal.

In order to realize the operation in the second mode, the charging and supplying unit 21 may further include a second comparator Com2, a first input terminal of the second comparator Com2 is coupled to the battery BAT2, a second input terminal of the second comparator Com2 inputs a second reference voltage VR2, the second reference voltage VR2 is greater than or equal to the effective output voltage of the battery BAT2, an output terminal of the second comparator Com2 is connected to the controller Ctrl, and the controller Ctrl determines whether the charging and supplying unit 21 can operate in the second mode according to the output results of the first comparator Com1 and the output terminal of the second comparator Com 2. Further, in the second mode, when the power is supplied, the controller Ctrl may be further configured to sample an output voltage at least one voltage output terminal, such as VO1 and/or VO2, and control the output voltage by controlling duty ratios of on and off of the plurality of switching devices according to the sampled output voltage.

In one example, the first reference voltage may be 4.5V. When VIN is greater than or equal to 4.5V, the charging and power supplying unit 21 can charge the battery BAT2 of the charging box by using VIN as input, and can also generate bypass voltage to output to the voltage output terminals VO1 and VO2 to operate in the first mode. When VIN is less than 4.5V, if the voltage of the battery BAT2 of the charging box is greater than the effective output voltage thereof, i.e. the second reference voltage VR2 is, for example, 3.2V, the charging and power supplying unit 21 can generate the output voltage by taking VBAT2 as an input and in a boosting manner.

With continued reference to fig. 3, the first connection terminal of the inductor L1 is coupled to the charging box battery BAT2, and the charging box circuit further includes a third capacitor CB, one end of which is coupled to the first connection terminal of the inductor L1, and the other end of which is grounded. In the first mode, the controller Ctrl is configured to control the plurality of switching devices to be turned on and off, such that the second connection terminal of the inductor L1 is alternately coupled to the voltage input terminal VIN and the first ground terminal, and the second connection terminal of the inductor L1 is simultaneously coupled to the at least one voltage output terminal when the second connection terminal of the inductor L1 is coupled to the voltage input terminal VIN.

In the second mode, the controller Ctrl is configured to control the plurality of switching devices to be turned on and off, such that the second connection terminal of the inductor L1 is alternately coupled to one of the at least one voltage output terminal and the first ground terminal. In one example, the at least one voltage output terminal includes a first voltage output terminal VO1 and a second voltage output terminal VO2, and in the second mode, the controller Ctrl controls the charging and power supplying unit 21 to generate an output voltage based on the voltage output from the battery BAT2 and the inductor L1, and alternately outputs the output voltage VO2 through the first voltage output terminal VO1 and the second voltage output terminal VO 2. That is, during the first half cycle, the second connection of the inductor L1 alternates between being coupled to the first voltage output terminal VO1 and being coupled to the first ground terminal; the second connection of the inductor L1 alternates between being coupled to the second voltage output terminal VO2 and being coupled to the first ground terminal during a second half-cycle, the first half-cycle and the second half-cycle forming a complete cycle.

In fig. 3, a first connection terminal of the inductor L1 is coupled to a first node N1, a second connection terminal of the inductor L1 is coupled to a second node N2, the plurality of switching devices includes a third switch S3 and a fourth switch S4, the third switch S3 is coupled between the voltage input terminal VIN and the second node N2, and the fourth switch S4 is coupled between the second node N2 and the first ground terminal. In one example, the at least one voltage output terminal may include a first voltage output terminal VO1, a first output capacitor C1 is disposed in series between the first voltage output terminal VO1 and ground, and the plurality of switching devices further include a first switch S1 coupled between the first voltage output terminal VO1 and a second node N2. In another example, the at least one voltage output terminal may include a second voltage output terminal VO2, a second output capacitor C2 is connected in series between the second voltage output terminal VO2 and ground, and the plurality of switching devices further include a second switch S2 coupled between the second voltage output terminal VO2 and a second node N2. In yet another example, the at least one voltage output terminal may include a first voltage output terminal VO1 and a second voltage output terminal VO2, a first output capacitor C1 is disposed between the first voltage output terminal VO1 and ground in series, a second output capacitor C2 is disposed between the second voltage output terminal VO2 and ground in series, and the plurality of switching devices further include a first switch S1 coupled between the first voltage output terminal VO1 and a second node N2 and a second switch S2 coupled between the second voltage output terminal VO2 and a second node N2.

In the first mode, the controller Ctrl is configured to control the third switch S3 and the fourth switch S4 to be alternately turned on, and when the third switch S3 is turned on, at least one of the first switch S1 and the second switch S2 is turned on.

In the second mode, the controller Ctrl is configured to control the third switch S3 to be continuously turned off, and to alternate the first sub-mode and the second sub-mode. In the first sub-mode, the controller Ctrl is configured to control the fourth switch S4 to be alternately turned on with the first switch S1; in the second sub-mode, the controller Ctrl is configured to control the fourth switch S4 to be alternately turned on with the second switch S2. That is, during the first half-cycle, the fourth switch S4 is alternately turned on with the first switch S1; the fourth switch S4 is alternately turned on with the second switch S2 during the second half-cycle, the first half-cycle and the second half-cycle forming a full cycle. At this time, the charging and supplying unit 21 may generate an output voltage in a boosting manner. It is understood that the charging and power supplying unit 21 may also directly output the voltage output by the battery BAT2 of the charging box to the voltage output terminal, and at this time, the fourth switch S4 is not conductive, and the first switch S1 and the second switch S2 may be alternately conductive.

The waveforms of the current in the inductor L1 and the waveforms of the switching control signals will be described by taking the charging and power supplying unit 21 including the first voltage output terminal VO1 and the second voltage output terminal VO2 as an example. The inductor current is defined to be positive when flowing from the second node N2 to the first node N1.

As shown in fig. 3, the charging and power supplying unit 21 may include a comparator Com1, a comparator Com2, switches S1 to S4, a capacitor C1, a capacitor C2, a capacitor CB, a controller Ctrl, and an inductor L1. When VIN is smaller than the reference voltage VR1, for example, 4.5V, and the voltage of the battery BAT2 of the charging box is smaller than the reference voltage VR2, for example, 3.2V, the controller Ctrl controls the switches S1 to S4 to be in an off state, and the charging and power supply unit 21 stops working.

When VIN is greater than VR1, for example, 4.5V, indicating that VIN is powered, at this time, the controller Ctrl controls the switch S3 and the switch S4 to alternately turn on to charge the battery BAT2 in a step-down manner, and controls the switch S1 and the switch S2 to turn on during a period in which the switch S3 is turned on, so as to simultaneously supply power to the first voltage output terminal VO1 and the second voltage output terminal VO2, where the voltages of the first voltage output terminal VO1 and the second voltage output terminal VO2 are approximately equal to VIN and generally slightly lower than VIN, and the reduced voltage is a voltage drop across the switch S3, the switch S1, or the switch S2; when the switch S3 is turned off, the control switch S1 and the switch S2 are also turned off, and the capacitor C1 and the capacitor C2 supply power to the wireless headset, that is, the capacitor C1 and the capacitor C2 can perform a voltage stabilizing function.

When the charging and power supplying unit 21 charges the battery BAT2 in a voltage reduction mode, a voltage negative feedback loop is formed by taking VBAT2 as input, so that constant voltage charging can be realized; the controller Ctrl acquires the voltage at N2, and the current information can be obtained by combining the voltage at the voltage input terminal VIN and the resistance of the third switch S3, so that a current negative feedback loop is formed, and constant-current charging can be realized.

Fig. 4 shows an exemplary waveform of the current in the inductor and the waveform of the switch control signal when the charging and power supplying unit is in the step-down charging state. As shown in fig. 4, IL is the inductor current waveform, the dashed line indicates zero current, and the inductor current is positive, indicating that the inductor current flows from N2 to N1. GS3 is the control signal for switch S3, GS4 is the control signal for switch S4, GS1 is the control signal for switch S1, and GS2 is the control signal for switch S2. In the period T1, GS3 is high, and controls the switch S3 to turn on, the inductor current rises, and stores energy in the inductor L1, and at this time, the switches S1 and S2 are also controlled to turn on. In the period of T2, GS3 is low, GS4 is high, switch S4 is controlled to be on, inductor current drops, inductor L1 discharges energy, and switch S1 and switch S2 are also controlled to be off at this time.

When VIN is less than VR1, for example, 4.5V, indicating that VIN is dead, the comparator Com2 compares VBAT2 with the reference voltage VR2, for example, 3.2V, and if the output of the comparator Com2 is high, that is, the voltage of VBAT2 is greater than 3.2V, indicating that the external power supply can be supported by the battery VBAT 2. In the time period T1 and the time period T2, the controller Ctrl may control the switch S4 and the switch S1 to be alternately turned on, so as to generate an output voltage in a boost manner, and supply power to the earphone through the first voltage output terminal VO 1; during the time period T3 and the time period T4, the controller Ctrl may control the switches S4 and S2 to alternately turn on, generate an output voltage in a boost manner, and supply power to the earphone through the second voltage output VO 2.

Fig. 5 illustrates an exemplary waveform of the current in the inductor and a waveform of the switching control signal when the charging and supplying unit is in the boost supplying state. As shown in fig. 5, IL is the inductor current waveform, the dashed line indicates zero current, and the inductor current is negative, indicating that the inductor current flows from N1 to N2. GS3 is the control signal for switch S3, GS4 is the control signal for switch S4, GS1 is the control signal for switch S1, and GS2 is the control signal for switch S2. From the period T1 to the period T4, the GS3 is constantly at the low level, and the switch S3 maintains the off state. In a period of time T1, GS4 is in a high level, the switch S4 is controlled to be switched on, the inductor current is reduced, but the absolute value of the inductor current is increased, and energy is stored in the inductor L1; in a period of T2, GS1 is at a high level, and controls the switch S1 to be turned on, the inductor current rises, but the absolute value of the inductor current falls, the inductor L1 releases energy, and charges are output to the first voltage output terminal VO 1; in a period of time T3, when the switch GS4 is at a high level, the switch S4 is controlled to be turned on, the inductor current decreases, but the absolute value of the inductor current increases, and energy is stored in the inductor L1; in the period T4, GS2 is high, and controls the switch S2 to be turned on, the inductor current rises, but the absolute value of the inductor current falls, the inductor L1 releases energy, and charges are output to the second voltage output terminal VO 2.

In addition, the utility model also provides a charging box which comprises the charging box circuit.

Fig. 6 is a schematic structural diagram of a charging circuit of a wireless headset assembly according to an embodiment of the present disclosure. Wherein, wireless earphone subassembly includes at least one wireless earphone and above-mentioned box that charges. As shown in fig. 6, the wireless headset assembly may include two wireless headsets, a first wireless headset and a second wireless headset, the first wireless headset having a voltage connection VCHG1 and a second ground and including a headset battery such as a bat. The second wireless headset has a voltage connection terminal VCHG2 and a second ground terminal, and includes a headset battery BATR, and when charging, the first ground terminal of the charging box is coupled to the second ground terminal, and the voltage output terminal of the charging box is coupled to the voltage connection terminal, such as VO1 coupled to VCHG1, and VO2 coupled to VCHG2, so that the voltage connection terminal can receive an output voltage output from the voltage output terminal, wherein the output voltage can charge the headset battery.

Further, the wireless headset may further include a communication unit, and when the output voltage of the charging box through the voltage output terminal, e.g., VO1 and/or VO2, can represent the data information, the communication unit (not shown) of the wireless headset can obtain the data information according to the output voltage.

In addition, the wireless earphone can be provided with other functional units according to requirements. In fig. 6, the first wireless headset further includes a charging management unit, ChargerL, a voltage regulating unit, DCDCL, an application processor, APL, and a radio frequency unit, RFL. The second wireless headset further comprises a charge management unit, ChargerR, a voltage regulation unit, DCDCR, an application processor, APR, and a radio frequency unit, RFR.

Those of skill would further appreciate that the various illustrative components and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A charging box circuit is characterized by comprising a charging box battery and a charging and power supplying unit, wherein the charging and power supplying unit comprises a controller, an inductor, a plurality of switching devices, a voltage input end, a battery end and at least one voltage output end;

the controller is configured to control on and off of the plurality of switching devices, so that the charging and power supplying unit operates in a first mode or a second mode, and the time-division multiplexing of the inductor is implemented, where:

when the voltage input by the voltage input end is greater than or equal to a first reference voltage, the charging and power supplying unit works in the first mode, the charging and power supplying unit can generate a charging voltage based on the voltage input by the voltage input end and the inductor, and the charging voltage is output to the charging box battery through the battery end, so that the switch charging is realized, and meanwhile, the charging and power supplying unit can output the voltage input by the voltage input end to the wireless earphone through the voltage output end;

when the voltage input by the voltage input end is less than a first reference voltage and the voltage of the charging box battery is greater than the effective output voltage of the charging box battery, the charging and power supplying unit works in the second mode, the charging and power supplying unit can generate an output voltage based on the charging box battery and the inductor and output the output voltage to the wireless earphone through the voltage output end, wherein the output voltage can provide a charging voltage for the wireless earphone battery to realize switch power supply,

the first connection end of the inductor is coupled with the charging box battery, the charging box circuit further comprises a third capacitor, one end of the third capacitor is coupled with the first connection end of the inductor, the other end of the third capacitor is grounded,

in the first mode, the controller is configured to control the plurality of switching devices to be turned on and off, such that the second connection terminal of the inductor is alternately coupled to the voltage input terminal and the first ground terminal, and the second connection terminal of the inductor is simultaneously coupled to the at least one voltage output terminal when the second connection terminal of the inductor is coupled to the voltage input terminal;

in the second mode, the controller is configured to control the plurality of switching devices to be turned on and off, such that the second connection terminal of the inductor is alternately coupled to one of the at least one voltage output terminal and the first ground terminal.

2. The charging box circuit of claim 1, wherein a first connection terminal of the inductor is coupled to a first node N1, a second connection terminal of the inductor is coupled to a second node N2, the plurality of switching devices comprises a third switch and a fourth switch, the third switch is coupled between the voltage input terminal and the second node N2, and the fourth switch is coupled between the second node N2 and the first ground terminal; the at least one voltage output terminal includes:

a first voltage output terminal, the plurality of switching devices further comprising a first switch coupled between the first voltage output terminal and the second node N2; and/or the presence of a gas in the atmosphere,

a second voltage output terminal, the plurality of switching devices further including a second switch coupled between the second voltage output terminal and the second node N2.

3. The charge box circuit of claim 2, wherein:

in the first mode, the controller is configured to control the third switch and the fourth switch to be alternately turned on, and when the third switch is turned on, at least one of the first switch and the second switch is turned on; alternatively, the first and second electrodes may be,

in the second mode, the controller is configured to control the third switch to be continuously switched off and to enable a first sub-mode and a second sub-mode to be alternately carried out, and in the first sub-mode, the controller is configured to control the fourth switch and the first switch to be alternately switched on; in the second sub-mode, the controller is configured to control the fourth switch to be alternately turned on with the second switch.

4. The charge box circuit of claim 1, wherein:

the charging and power supplying unit comprises a first comparator, a first input end of the first comparator is coupled with the voltage input end, a second input end of the first comparator inputs the first reference voltage, an output end of the first comparator is connected with the controller, and the controller judges whether the charging and power supplying unit can work in the first mode according to a result output by the output end of the first comparator;

the charging and power supplying unit comprises a second comparator, a first input end of the second comparator is coupled with the charging box battery, a second reference voltage is input to a second input end of the second comparator, the second reference voltage is larger than or equal to the effective output voltage, an output end of the second comparator is connected with the controller, and the controller judges whether the charging and power supplying unit can work in the second mode according to results output by output ends of the first comparator and the second comparator.

5. The charging box circuit according to any of claims 1-4, wherein:

in the first mode, the controller is further configured to sample a charging current, and control on and off duty ratios of the plurality of switching devices according to the sampled charging current, so as to realize constant-current charging control of the charging box battery; in the first mode, the controller is further configured to sample a charging voltage and control on and off duty ratios of the plurality of switching devices according to the sampled charging voltage, so as to realize constant-voltage charging control of the charging box battery; in the second mode, the controller is further configured to sample an output voltage at the at least one voltage output terminal, and control the output voltage by controlling duty ratios of on and off of the plurality of switching devices according to the sampled output voltage; and/or the presence of a gas in the atmosphere,

the at least one voltage output end comprises a first voltage output end and a second voltage output end, and a first output capacitor is arranged between the first voltage output end and the ground in series; a second output capacitor is arranged between the second voltage output end and the ground in series; in the second mode, the controller controls the charging and power supplying unit to generate an output voltage based on the voltage output from the charging box battery and the inductance and alternately output through the first voltage output terminal and the second voltage output terminal.

6. A charging box characterized by comprising a charging box circuit according to any one of claims 1-5.

7. A wireless headset assembly, comprising:

a wireless earphone having a voltage connection terminal and a second ground terminal and including an earphone battery;

the charging box according to claim 6, wherein the first ground terminal of the charging box is coupled to the second ground terminal, and the voltage output terminal of the charging box is coupled to the voltage connection terminal, so that the voltage connection terminal can receive the output voltage outputted from the voltage output terminal, and the output voltage can charge the earphone battery.