Earphone box circuit, earphone box and earphone charging system

Abstract

The embodiment of the present application provides an earphone box circuit, an earphone box and an earphone charging system, which relates to the field of earphone charging technology, and can realize the charging function of the earphone through a relatively simple voltage conversion circuit structure. The earphone box circuit is used for the earphone box of wireless earphones, and the earphone box circuit includes: an earphone box battery terminal and an earphone charging terminal; a voltage conversion circuit, and the voltage conversion circuit includes: a first transistor; a first diode, the first diode is connected in parallel to the first transistor; a second transistor; an inductor, the inductor is connected in series between the second end of the first transistor and the battery terminal of the earphone box; a first capacitor, the first capacitor is connected in series between the earphone charging terminal and the grounding point; the voltage conversion circuit is at least used to work in a battery power boost mode, in which the first transistor is cut off and the second transistor works in an alternating on and off state, forming a boost circuit with the earphone box battery terminal as the input terminal and the earphone charging terminal as the output terminal.

Description

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 17, 2021, with application number 202111090399.3 and application name “Earphone Box Circuit, Earphone Box and Earphone Charging System”, the entire contents of which are incorporated by reference in this application. Technical Field

[0002] The present application relates to the field of earphone charging technology, and in particular to an earphone box circuit, an earphone box and an earphone charging system. Background Art

[0003] Current wireless headphones generally need to be used in conjunction with a headphone box. When the wireless headphones are placed in the headphone box, the terminals on the headphones contact the terminals in the headphone box to electrically connect the headphones and the headphone box. Through the voltage conversion circuit in the headphone box, the headphone box battery can charge the headphones. However, the voltage conversion circuit structure in the current headphone box is relatively complex. Summary of the invention

[0004] An earphone box circuit, an earphone box and an earphone charging system can realize the charging function of the earphone through a relatively simple voltage conversion circuit structure.

[0005] In a first aspect, an earphone box circuit is provided, which is used for an earphone box of a wireless earphone, and the earphone box circuit includes: an earphone box battery terminal and an earphone charging terminal; a voltage conversion circuit, and the voltage conversion circuit includes: a first transistor, and a first end of the first transistor is electrically connected to the earphone charging terminal; a first diode, the first diode is connected in parallel to the first transistor, an anode of the first diode is electrically connected to the second end of the first transistor, and a cathode of the first diode is electrically connected to the first end of the first transistor; a second transistor, a first end of the second transistor is electrically connected to the second end of the first transistor, and the second end of the second transistor is grounded; an inductor, the inductor is connected in series between the second end of the first transistor and the battery terminal of the earphone box; a first capacitor, the first capacitor is connected in series between the earphone charging terminal and a grounding point; the voltage conversion circuit is at least used to work in a battery power-taking boost mode, in which the first transistor is cut off and the second transistor works in alternating on and off states, so that the first diode, the second transistor, the inductor and the capacitor constitute a boost circuit with the earphone box battery terminal as an input terminal and the earphone charging terminal as an output terminal.

[0006] In a possible implementation, the voltage conversion circuit also includes: an earphone box charging terminal, the earphone box charging terminal is electrically connected to the earphone charging terminal; a second diode, the second diode is connected in parallel to the second transistor, the anode of the second diode is electrically connected to the second end of the second transistor, and the cathode of the second diode is electrically connected to the first end of the second transistor; a second capacitor, the second capacitor is connected in series between the battery terminal of the earphone box and the grounding point; the voltage conversion circuit is also used to operate in a charging terminal power supply mode. In the charging terminal power supply mode, the first transistor operates in alternating on and off states, and the second transistor is cut off, so that the second diode, the first transistor, the inductor and the second capacitor constitute a step-down circuit with the earphone charging terminal as the input terminal and the earphone box battery terminal as the output terminal.

[0007] In a possible implementation, the voltage conversion circuit further includes: a third transistor, the earphone box charging end is electrically connected to the earphone charging end through the third transistor, wherein the first end of the third transistor is electrically connected to the earphone box charging end, and the second end of the third transistor is electrically connected to the earphone charging end.

[0008] In a possible implementation, the voltage conversion circuit is further configured to operate in a battery power supply direct-through mode. In the battery power supply direct-through mode, the first transistor is turned on and the second transistor is turned off.

[0009] In a possible implementation, the earphone box circuit also includes a control unit, which is electrically connected to the control end of the first transistor and the control end of the second transistor, and the control unit is used to: obtain the voltage of the earphone battery of the wireless earphone connected to the earphone box circuit, and obtain the voltage at the battery end of the earphone box; and control the voltage conversion circuit to operate in a battery power boost mode or a battery power pass-through mode according to the relationship between the voltage at the battery end of the earphone box and the voltage of the earphone battery of the wireless earphone.

[0010] In a possible implementation, the process of controlling the voltage conversion circuit to operate in a battery power boost mode or a battery power pass-through mode according to the relationship between the voltage at the battery terminal of the earphone box and the voltage of the earphone battery of the wireless earphone includes: if the voltage at the battery terminal of the earphone box is less than the voltage of the earphone battery of the wireless earphone, then controlling the voltage conversion circuit to operate in the battery power boost mode; if the voltage at the battery terminal of the earphone box is greater than the voltage of the earphone battery of the wireless earphone, then controlling the voltage conversion circuit to operate in the battery power pass-through mode.

[0011] In a possible implementation, the earphone box circuit also includes a control unit, which is electrically connected to the control end of the first transistor and the control end of the second transistor, and the control unit is used to: obtain the connection status of the charging end of the earphone box, obtain the voltage of the earphone battery of the wireless earphone connected to the earphone box circuit, and obtain the voltage of the battery end of the earphone box; according to the connection status of the charging end of the earphone box, the voltage of the earphone battery of the wireless earphone and the voltage of the battery end of the earphone box, control the voltage conversion circuit to operate in a battery power boost mode or a charging end power mode.

[0012] In a possible implementation, the process of controlling the voltage conversion circuit to operate in a battery power-taking boost mode or a charging end power-taking mode according to the connection state of the earphone box charging terminal, the voltage of the earphone battery of the wireless earphone, and the voltage at the battery terminal of the earphone box includes: if the earphone box charging terminal is in a non-plugged state, and the voltage at the battery terminal of the earphone box is less than the voltage of the earphone battery of the wireless earphone, then controlling the voltage conversion circuit to operate in a battery power-taking boost mode; if the earphone box charging terminal is in a plugged state, then controlling the voltage conversion circuit to operate in a charging end power-taking mode.

[0013] In a possible implementation, the control unit is also used to: if the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is greater than the voltage of the earphone battery of the wireless earphone, then control the voltage conversion circuit to operate in a battery power pass-through mode. In the battery power pass-through mode, the first transistor is turned on and the second transistor is turned off.

[0014] In a possible implementation, a wireless headset electrically connected to an earphone box includes a first earphone and a second earphone, the first earphone includes a first earphone battery, and the second earphone includes a second earphone battery; if the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is greater than the voltage of the earphone battery of the wireless headset, the process of controlling the voltage conversion circuit to operate in a battery power pass-through mode includes: if the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is greater than the maximum value of the voltage of the first earphone battery and the voltage of the second earphone battery, then controlling the voltage conversion circuit to operate in a battery power pass-through mode; if the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is less than the maximum value of the voltage of the earphone battery of the wireless headset, Voltage, then the process of controlling the voltage conversion circuit to work in the battery power boost mode includes: if the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is less than the minimum value between the voltage of the first earphone battery and the voltage of the second earphone battery, then the voltage conversion circuit is controlled to work in the battery power boost mode; the control unit is also used for: if the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is between the voltage of the first earphone battery and the voltage of the second earphone battery, then the voltage conversion circuit is controlled to work in the battery power pass-through mode until the voltage at the battery terminal of the earphone box is equal to the minimum value between the voltage of the first earphone battery and the voltage of the second earphone battery, and the voltage conversion circuit is controlled to work in the battery power boost mode.

[0015] In a possible implementation, the control unit is also used to obtain the current passing through the inductor in the battery power boost mode, and control the voltage conversion circuit to operate in the battery power boost mode based on the output voltage, wherein the output voltage is greater than the minimum value of the voltage of the first earphone battery and the voltage of the second earphone battery, and when the current passing through the inductor is less than a preset value, the output voltage is increased.

[0016] In a possible implementation, the earphone box circuit also includes a control unit, which is electrically connected to the control end of the third transistor, and the control unit is used to: obtain the connection status of the charging end of the earphone box; if the charging end of the earphone box is in a non-plugged state, control the third transistor to be cut off; if the charging end of the earphone box is in a plugged state, control the third transistor to be cut off.

[0017] In a possible implementation, the first transistor, the second transistor and the third transistor are metal-oxide semiconductor field effect transistors.

[0018] In a possible implementation, the voltage conversion circuit further includes: a third diode, the third diode is connected in parallel to the third transistor, the anode of the third diode is electrically connected to the first end of the third transistor, and the cathode of the third diode is electrically connected to the second end of the third transistor.

[0019] In a possible implementation, the charging end of the earphone box is a Type-C interface.

[0020] In a second aspect, an earphone box is provided, comprising the above-mentioned earphone box circuit.

[0021] In a third aspect, an earphone charging system is provided, comprising at least one wireless earphone and the above-mentioned earphone box.

[0022] The earphone box circuit, earphone box and earphone charging system in the embodiment of the present application, through the voltage conversion circuit composed of the first transistor, the second transistor, the first diode and the first capacitor, based on the control of the working state of the first transistor and the second transistor, can make the voltage conversion circuit form a boost circuit with the earphone box battery end as the input end and the earphone charging end as the output end, so as to realize charging the earphone from the earphone box battery by boosting, and the circuit structure is simple and the cost is low. In addition, by controlling the first transistor, the charging function in other modes can be realized when the boost circuit function is not needed, that is, the combination of other charging functions on the basis of the boost circuit function is realized through a relatively simple circuit structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the structure of an earphone charging system in an embodiment of the present application;

[0024] Figure 2 for Figure 1 The structural block diagram of the wireless headset and the headset box when connected;

[0025] Figure 3 for Figure 2 The corresponding circuit diagram;

[0026] Figure 4 for Figure 3 A schematic diagram of a state of the medium voltage conversion circuit in the battery power boost mode;

[0027] Figure 5 for Figure 3 Another state diagram of the medium voltage conversion circuit in the battery power boost mode;

[0028] Figure 6 for Figure 3 A schematic diagram of a state of the medium voltage conversion circuit in the battery power boost mode;

[0029] Figure 7 for Figure 3 Schematic diagram of another state of the medium voltage conversion circuit in the battery power boost mode. DETAILED DESCRIPTION

[0030] The terms used in the implementation section of this application are only used to explain the specific embodiments of this application and are not intended to limit this application.

[0031] like Figure 1 and Figure 2 As shown, an embodiment of the present application relates to an earphone charging system consisting of an earphone box and earphones. The earphone charging system generally includes an earphone box and two earphones. The earphones can be wireless earphones. The earphones have terminals, and the earphone box has terminals. When the earphones are placed in the earphone box, the terminals on the earphones are in contact with the terminals on the earphone box to electrically connect the earphones and the earphone box. When the earphones and the earphone box are electrically connected, the two can communicate and charge. Furthermore, when the earphones are electrically connected to the earphone box, the charging end of the earphone box is electrically connected to the earphones through the voltage conversion circuit in the earphone box circuit, and the earphone box battery is electrically connected to the earphones through the voltage conversion circuit, wherein the charging end of the earphone box is used to plug in an external power supply, the earphone box battery is used to store energy in the earphone box, the voltage conversion circuit is used to perform voltage conversion to realize the charging function, and the control unit is used to realize the control of the voltage conversion circuit. For example, when the charging end of the earphone box is not plugged in to an external power supply, for example, when the user carries the earphone box with him and needs to charge the earphones, the earphones are placed in the earphone box, and the earphone box battery can charge the earphones through the voltage conversion circuit; when the battery of the earphone box is low on power, the user can plug the charging end of the earphone box into an external power supply, and at this time, the charging end of the earphone box can charge the earphone box battery through the voltage conversion circuit; in addition, when the charging end of the earphone box is plugged in to an external power supply, the charging end of the earphone box can charge the earphones.

[0032] like Figure 3As shown, the embodiment of the present application provides an earphone box circuit 1, an earphone box 2 for wireless earphones, the earphone box circuit 1 includes: an earphone box battery terminal O1 and an earphone charging terminal O2, wherein the earphone box 2 includes the earphone box circuit 1 and an earphone box battery B1, in the earphone box 2, the earphone box battery terminal O1 is electrically connected to the positive electrode of the earphone box battery B1, and the negative electrode of the earphone box battery B1 is grounded, when the earphone 3 is placed in the earphone box 2, the earphone charging terminal O2 is electrically connected to the earphone 3; a voltage conversion circuit 4, the voltage conversion circuit 4 includes: a first transistor Q1, a first end of the first transistor Q1 is electrically connected to the earphone charging terminal O2; a first diode D1, the first diode D1 is connected in parallel to the first transistor Q1, the anode of the first diode D1 is electrically connected to the second end of the first transistor Q1, and the first diode D1 The cathode of the first transistor Q1 is electrically connected to the first end of the first transistor Q1; the second transistor Q2, the first end of the second transistor Q2 is electrically connected to the second end of the first transistor Q1, and the second end of the second transistor Q2 is grounded; the inductor L, the inductor is connected in series between the second end of the first transistor Q1 and the battery end O1 of the earphone box; the first capacitor C1, the first capacitor C1 is connected in series between the earphone charging end O2 and the grounding point; the voltage conversion circuit 4 is at least used to work in the battery power taking boost mode. In the battery power taking boost mode, the first transistor Q1 is controlled to be cut off and the second transistor Q2 is controlled to work in an alternating on and off state, so that the first diode D1, the second transistor Q2, the inductor L and the first capacitor C1 constitute a boost circuit with the earphone box battery end O1 as the input end and the earphone charging end O2 as the output end.

[0033] Specifically, during the periodic on and off process of the second transistor Q2, as shown in FIG. Figure 4 As shown in FIG. 1 , when the second transistor Q2 is turned on, the current flows as shown by the arrow, and the earphone box battery terminal O1 serves as the input terminal. The earphone box battery terminal O1 is short-circuited with the ground point after passing through the inductor L, that is, the current of the earphone box battery terminal O1 charges the inductor L, and the first diode D1 prevents the first capacitor C1 from discharging to the ground; Figure 5As shown, when the second transistor Q2 is turned off, due to the current holding characteristic of the inductor L, the current flowing through the inductor L will gradually decrease. Since the second transistor Q2 is turned off, the current at the battery terminal O1 of the earphone box no longer flows to the ground after passing through the inductor L. Therefore, the inductor L starts to charge the first capacitor C1, and the voltage across the capacitor C1 increases. Even if the voltage at the earphone charging terminal O2 is higher than the voltage at the battery terminal O1 of the earphone box, the second transistor Q2 is periodically turned on and off, so that the above two processes are repeated, that is, the voltage at the battery terminal O1 of the earphone box can be increased and then output at the earphone charging terminal O2, that is, the earphone box battery B1 can charge the earphone 3 by boosting. For the first transistor Q1, it remains in the cut-off state in the battery power taking boost mode, so as to form a boost circuit through other devices, so as to charge the earphone after boosting the lower voltage of the earphone box battery terminal O1; in other modes, for example, if the process of charging the earphone from the earphone box does not require boosting, the first transistor Q1 can be directly controlled to be turned on and the second transistor Q2 can be turned off, then the charging current can directly flow to the earphone through the first transistor Q1 and the first diode D1, so that the earphone box battery terminal O1 can charge the earphone battery with a larger current, thereby realizing the direct charging function; in addition, if the earphone charging terminal O2 is connected to an external power supply, the first transistor Q1 can be controlled to be turned on, so that the external power supply can charge the earphone box battery through the turned-on first transistor Q1.

[0034] The earphone box circuit in the embodiment of the present application is a voltage conversion circuit composed of a first transistor, a second transistor, a first diode and a first capacitor. Based on the control of the working state of the first transistor and the second transistor, the voltage conversion circuit can form a boost circuit with the battery end of the earphone box as the input end and the charging end of the earphone as the output end, so as to charge the earphone from the earphone box battery by boosting. The circuit structure is simple and the cost is low. In addition, by controlling the first transistor, the charging function in other modes can be realized when the boost circuit function is not needed, that is, the combination of other charging functions on the basis of the boost circuit function is realized through a relatively simple circuit structure.

[0035] In a possible implementation, the voltage conversion circuit 4 is also used to operate in a battery power pass-through mode. In the battery power pass-through mode, the first transistor Q1 is turned on and the second transistor Q2 is turned off. At this time, a direct current can be realized from the earphone box battery terminal O1 to the earphone charging terminal O2, and the earphone 3 can be charged in a direct manner rather than in a boosting manner. That is, the direct charging function of the earphone box battery B1 to the earphone 3 can be realized, thereby realizing the direct charging function and boost charging function of the earphone box battery B1 to the earphone 3 through a relatively simple circuit structure.

[0036] In a possible implementation, the wireless headset 3 includes an earphone battery B2. When the wireless headset 3 is placed in the earphone box 2, the positive electrode of the earphone battery B2 in the wireless headset 3 is electrically connected to the earphone charging terminal O2, so that the earphone box 2 charges the earphone battery B2. The negative electrode of the earphone battery B2 is grounded. The earphone box circuit 1 also includes a control unit 5. The control unit 5 is electrically connected to the control end of the first transistor Q1 and the control end of the second transistor Q2. The control unit 5 is used to: obtain the voltage of the earphone battery of the wireless headset 3 connected to the earphone box circuit 1, and obtain the voltage of the earphone box battery terminal O1; control the voltage conversion circuit 4 to operate in a battery power boost mode or a battery power pass-through mode according to the relationship between the voltage of the earphone box battery terminal O1 and the voltage of the earphone battery of the wireless headset 3.

[0037] In a possible implementation, the process of controlling the voltage conversion circuit 4 to operate in a battery power boost mode or a battery power pass-through mode according to the relationship between the voltage at the earphone box battery terminal O1 and the voltage of the earphone battery of the wireless earphone 3 includes: if the voltage at the earphone box battery terminal O1 is less than the voltage of the earphone battery of the wireless earphone 3, then the voltage conversion circuit 4 is controlled to operate in the battery power boost mode; if the voltage at the earphone box battery terminal O1 is greater than the voltage of the earphone battery of the wireless earphone 3, then the voltage conversion circuit 4 is controlled to operate in a battery power pass-through mode, and in the battery power pass-through mode, the first transistor Q1 is controlled to be turned on and the second transistor Q2 is controlled to be turned off. Different modes of the voltage conversion circuit 4 are realized by controlling the state of the transistor, wherein the control unit 5 can control the signal transmitted to the control end of the transistor to control the on and off state of the transistor. For example, when the control unit 5 outputs the off level to the control end of the first transistor Q1, the first transistor Q1 can be controlled to be off. When the control unit 5 outputs the on level to the control end of the first transistor Q1, the first transistor Q1 can be controlled to be on. When the control unit 5 transmits a pulse width modulation (PWM) signal to the second transistor Q2, the second transistor Q2 can be controlled to work in an alternating on and off state. The PWM signal consists of an on level and an off level, wherein the on level is used to control the on state of the second transistor Q2, and the off level is used to control the off state of the second transistor Q2. The on level and the off level are related to the type of transistor. For example, for an n-type transistor, a high level is an on level and a low level is an off level. For a p-type transistor, a high level is an off level and a low level is an on level. The control unit 5 can be, for example, a microcontroller unit (MCU) in the earphone box 2.

[0038] Specifically, for example, the maximum voltage value of the earphone box battery B1 is 4.43V, and the maximum voltage value of the earphone battery B2 is 4.43V. When the wireless earphone 3 is placed in the earphone box 2 and the earphone battery B2 needs to be charged through the earphone box battery B1, the current voltage of the earphone box battery B1 and the current voltage of the earphone battery B2 can be first obtained through the control unit 5. If it is determined that the current voltage of the earphone box battery B1 is less than the current voltage of the earphone battery B2, the voltage of the earphone box battery B1 needs to be boosted before the earphone battery B2 can be charged. Therefore, at this time, the voltage conversion circuit 4 is controlled to operate in the above-mentioned battery power taking boost mode. By controlling the on and off states of the first transistor Q1 and the second transistor Q2, the voltage conversion circuit 4 forms a boost circuit with the earphone box battery terminal O1 as the input terminal and the earphone charging terminal O2 as the output terminal, that is, the lower voltage of the earphone box battery B1 can be boosted by the voltage conversion circuit 4 to charge the earphone battery B2. If it is determined that the current voltage of the earphone box battery B1 is greater than the current voltage of the earphone battery B2, the earphone box battery B1 can directly charge the earphone battery B2. Therefore, the voltage conversion circuit 4 can be controlled to operate in the battery power pass-through mode. In this mode, the first transistor Q1 is turned on and the second transistor Q2 is turned off. The higher voltage provided by the earphone box battery B1 can directly charge the earphone battery B2, and there is no need to achieve voltage conversion through the control of the transistor, thereby saving power consumption.

[0039] In a possible implementation, the voltage conversion circuit 4 further includes: a second diode D2, the second diode D2 is connected in parallel to the second transistor Q2, the anode of the second diode D2 is electrically connected to the second end of the second transistor Q2, and the cathode of the second diode D2 is electrically connected to the first end of the second transistor Q2; an earphone box charging terminal O3, the earphone box charging terminal O3 is electrically connected to the earphone charging terminal O2, it should be noted that, Figure 3 The figure illustrates the way in which the earphone box charging terminal O3 is electrically connected to the earphone charging terminal O2 through the third transistor Q3 and the third diode D3. In other possible implementations, the earphone box charging terminal O3 can be directly electrically connected to the earphone charging terminal O2 without passing through other devices; the second capacitor C2 is connected in series between the earphone box battery terminal O1 and the grounding point; the voltage conversion circuit 4 is also used to work in the charging terminal power supply mode. In the charging terminal power supply mode, the first transistor Q1 works in alternating on and off states, and the second transistor Q2 is turned off, so that the second diode D2, the first transistor Q1, the inductor L and the second capacitor C2 constitute a step-down circuit with the earphone charging terminal O2 as the input terminal and the earphone box battery terminal O1 as the output terminal.

[0040] Specifically, during the periodic on and off process of the first transistor Q1, as shown in FIG. Figure 6As shown, when the first transistor Q1 is turned on, the current from the earphone charging terminal O2 passes through the inductor L and charges the earphone box battery B1, and the current of the inductor L rises, that is, the inductor L is charged; Figure 7 As shown, when the first transistor Q1 is turned off, since the inductor L is disconnected from the earphone charging terminal O2, the inductor L and the second diode D2 form a loop to charge the earphone box battery B1, and the current of the inductor L decreases. The first transistor Q1 alternately repeats the two states of on and off, that is, the voltage of the earphone charging terminal O2 can be stepped down and output at the earphone box battery terminal O1. Since the earphone charging terminal O2 is electrically connected to the earphone box charging terminal O3, the earphone box charging terminal O3 can be charged to the earphone box battery B1 by stepping down. In other words, through a relatively simple design, the functions of charging the earphone box battery through an external power source and charging the earphone battery through the earphone box battery can be realized. It can be seen that through the above circuit structure, the step-up change from the earphone box battery terminal O1 to the earphone charging terminal O2 can be realized to realize the step-up charging function of the earphone box battery B1 to the earphone 3; and the step-down conversion from the earphone box charging terminal O3 to the earphone box battery terminal O1 can be realized to realize the step-down charging function of the external power source to the earphone box battery B1. The boost charging function and the buck charging function reuse the inductor L to realize voltage conversion, and there is no need to provide two different voltage conversion circuits for the two functions, thereby simplifying the circuit.

[0041] In a possible implementation, the voltage conversion circuit 4 also includes a control unit 5, which is specifically used to: obtain the connection status of the earphone box charging terminal O3, obtain the voltage of the earphone battery of the wireless earphone 3 connected to the earphone box circuit 1, and obtain the voltage of the earphone box battery terminal O1; according to the connection status of the earphone box charging terminal O3, the voltage of the earphone battery of the wireless earphone 3 and the voltage of the earphone box battery terminal O1, the voltage conversion circuit 4 is controlled to operate in a battery power boost mode or a charging terminal power mode.

[0042] In a possible implementation, the process of controlling the voltage conversion circuit 4 to operate in the battery power boost mode or the charging terminal power mode according to the connection state of the earphone box charging terminal O3, the voltage of the earphone battery of the wireless earphone 3, and the voltage of the earphone box battery terminal O1 includes:

[0043] If the earphone box charging terminal O3 is in a non-plugged state, and the voltage of the earphone box battery terminal O1 is lower than the voltage of the earphone battery of the wireless earphone 3, the voltage conversion circuit 4 is controlled to work in a battery power-taking boosting mode, so that the voltage of the earphone box battery B1 is boosted and then charged to the earphone battery B2; if the earphone box charging terminal O3 is in a non-plugged state, and the voltage of the earphone box battery terminal O1 is higher than the voltage of the earphone battery of the wireless earphone 3, the voltage conversion circuit 4 is controlled to work in a battery power-taking direct-through mode. In the battery power-taking direct-through mode, the first transistor Q1 is turned on and the second transistor Q2 is turned off, so that the earphone box battery B1 directly charges the earphone battery B2; if the earphone box charging terminal O3 is in a plugged state, the voltage conversion circuit 4 is controlled to work in a charging terminal power-taking mode. In the charging terminal power-taking mode, the third transistor Q3 is controlled to be turned on, the first transistor Q1 is controlled to work in an alternating on and off state, and the second transistor Q2 is controlled to be turned off, so that the voltage conversion circuit 4 forms a step-down circuit with the earphone box charging terminal O3 as the input terminal and the earphone box battery terminal O1 as the output terminal.

[0044] Specifically, in this embodiment, the connection state of the earphone box charging terminal O3 is pre-determined. In the non-plugged state, the earphone 3 cannot be charged by the external power supply, and the earphone 3 can only be charged by the earphone box 2. Therefore, the voltage condition of the earphone box battery terminal O1 is further combined to control the voltage conversion circuit 4 to work in different battery power-taking modes. The specific process and principle of the battery power-taking boost mode and the battery power-taking direct mode are the same as those of the above embodiment, and are not repeated here. When the earphone box charging terminal O3 is in the plugged state, it means that the external power supply can be used for charging. At this time, the control voltage conversion circuit 4 works in the charging terminal power-taking mode. When the earphone box charging terminal O3 is in the plugged state, for example, the voltage value of the earphone box charging terminal O3 is 5V, and the first transistor Q1 is periodically turned on and off, that is, the voltage of the earphone box charging terminal O3 can be stepped down and output at the earphone box battery terminal O1, that is, the earphone box charging terminal O3 can charge the earphone box battery B1 by stepping down. In other words, through a relatively simple design, the functions of charging the earphone box battery through an external power supply and charging the earphone battery through the earphone box battery can be realized.

[0045] It should also be noted that, in addition to the earphone battery B2, each wireless headset 3 also includes a load switch 31 and a low dropout regulator (LDO) 32. When the earphone box charging terminal O3 is in a plugged-in state, the earphone battery B2 is electrically connected to the earphone charging terminal O2 through the low dropout regulator 32 and the load switch 31, wherein the load switch 31 is connected in series between the earphone charging terminal O2 and the low dropout regulator 32, and the low dropout linear regulator 32 is connected in series between the load switch 31 and the positive electrode of the earphone battery B2. The LDO is used to charge the earphone battery B2 based on the voltage output by the earphone box 2 at the earphone charging terminal O2, and the load switch 31 is used to protect the earphone battery B2. For example, when the earphone box charging terminal O3 is in a plugged state, the earphone battery B2 can be charged by taking power from the earphone box charging terminal O3, that is, the earphone 3 is charged through an external power source. When the earphone box charging terminal O3 is in a plugged state, the third transistor Q3 is turned on, so the earphone box charging terminal O3 can directly supply power to the earphone 3. Since the voltage 5V of the earphone box charging terminal O3 is greater than the maximum voltage 4.43V of the earphone battery B2, at this time, the earphone battery B2 is charged after the voltage is converted by the low voltage difference linear regulator 32, that is, the function of charging the earphone battery B2 through an external power source is realized. In other words, through a relatively simple design, the related functions of charging the earphone box battery through an external power source, charging the earphone battery through the earphone box battery, and charging the earphone battery through an external power source can be realized.

[0046] In a possible implementation, the wireless earphone electrically connected to the earphone box 2 includes a first earphone 301 and a second earphone 302 , the first earphone 301 includes a first earphone battery B2A, and the second earphone 302 includes a second earphone battery B2B.

[0047] The above process of controlling the voltage conversion circuit 4 to work in the battery power pass-through mode if the charging terminal O3 of the earphone box is in a non-plugged state and the voltage of the battery terminal O1 of the earphone box is greater than the voltage of the earphone battery of the wireless earphone includes: if the charging terminal O3 of the earphone box is in a non-plugged state and the voltage of the battery terminal O1 of the earphone box is greater than the maximum value of the voltage of the first earphone battery B2A and the voltage of the second earphone battery B2B, controlling the voltage conversion circuit 4 to work in the battery power pass-through mode;

[0048] The above process of controlling the voltage conversion circuit 4 to work in the battery power boosting mode if the charging terminal O3 of the earphone box is in a non-plugged state and the voltage of the battery terminal O1 of the earphone box is less than the voltage of the earphone battery of the wireless earphone includes: if the charging terminal O3 of the earphone box is in a non-plugged state and the voltage of the battery terminal O1 of the earphone box is less than the minimum value of the voltage of the first earphone battery B2A and the voltage of the second earphone battery B2B, controlling the voltage conversion circuit 4 to work in the battery power boosting mode;

[0049] The control unit 5 is also used for: if the charging terminal O3 of the earphone box is in a non-plugged state, and the voltage of the battery terminal O1 of the earphone box is between the voltage of the first earphone battery B2A and the voltage of the second earphone battery B2B, then the voltage conversion circuit 4 is controlled to operate in a battery power pass-through mode until the voltage of the battery terminal O1 of the earphone box is equal to the minimum value of the voltage of the first earphone battery B2A and the voltage of the second earphone battery B2B, and the voltage conversion circuit 4 is controlled to operate in a battery power boost mode.

[0050] In a possible implementation, the control unit 5 is further used to obtain the current passing through the inductor L in the battery power boost mode, and control the voltage conversion circuit 4 to work in the battery power boost mode based on the output voltage, and the output voltage is greater than the minimum value of the voltage of the first earphone battery B2A and the voltage of the second earphone battery B2B, and when the current passing through the inductor L is less than the preset value, the output voltage is increased. This step-by-step boost method can further improve the charging effect.

[0051] Specifically, the control unit 5 is communicatively connected to the first earphone 301 and the second earphone 302. For example, the control unit 5 can realize the communication connection through a universal asynchronous receiver / transmitter (UART) protocol, and the control unit 5 can obtain the voltage of the earphone battery through the communication connection between the first earphone 301 and the second earphone 302. The following is described through embodiments in several specific scenarios.

[0052] Assume that before charging, the control unit 5 obtains the voltage VB2A=3.4V of the first earphone battery B2A, the voltage VB2B=3.1V of the second earphone battery B2B, and the voltage VB1=4V of the earphone box battery B1 (i.e., the earphone box battery terminal O1). At this time, the earphone box charging terminal O3 is in a non-plugged state, and VB1 is greater than the maximum value of VB2A and VB2B. At this time, the voltage conversion circuit 4 is controlled to operate in the battery power pass-through mode to charge the two earphone batteries. During the charging process, VB2A and VB2B gradually increase, and VB1 gradually decreases. When VB1 decreases to equal VB2A or VB2B, the control unit 5 controls the voltage conversion circuit 4 to operate in the battery power boost mode to charge the earphone batteries until VB2A and VB2B are both charged to the maximum value of 4.43V. In this process, there are multiple specific charging methods for controlling the voltage conversion circuit 4 to work in the battery power taking and boosting mode, such as directly setting the output voltage of the voltage conversion circuit 4 to 4.43V for charging, or first setting the output voltage of the voltage conversion circuit 4 to be slightly larger than VB2A or VB2B, and then gradually increasing the output voltage of the voltage conversion circuit 4 until VB2A and VB2B are both charged to the maximum value of 4.43V. Among them, charging by continuously adjusting the voltage in a direct charging manner is more efficient.

[0053] Assume that before charging, the control unit 5 obtains the voltage VB2A=4.2V of the first earphone battery B2A, the voltage VB2B=4.1V of the second earphone battery B2B, and the voltage VB1=4V of the earphone box battery B1 (that is, the earphone box battery terminal O1). At this time, the earphone box charging terminal O3 is in a non-plugged state, and VB1 is less than the minimum value of VB2A and VB2B. At this time, the control voltage conversion circuit 4 operates in the battery power boost mode to charge the two earphone batteries until VB2A and VB2B are both charged to the maximum value of 4.43V. In this process, the voltage conversion circuit 4 is controlled to work in the battery power taking boost mode. Specifically, there can be a variety of charging methods, such as directly setting the output voltage of the voltage conversion circuit 4 to 4.43V for charging, or first setting the output voltage of the voltage conversion circuit 4 to be slightly larger than VB2B, and then gradually increasing the output voltage of the voltage conversion circuit 4 until VB2A and VB2B are both charged to the maximum value of 4.43V. For example, first set the output voltage of the voltage conversion circuit 4 to 3.5V+20mV for charging, VB2B gradually increases, and the current passing through the inductor L gradually decreases. When the current decreases to below the preset value, it is considered that the output voltage of the voltage conversion circuit 4 and the voltage difference between VB2B are small. At this time, the output voltage of the voltage conversion circuit 4 is increased. And so on. Based on the current passing through the inductor L, the output voltage of the voltage conversion circuit 4 is gradually increased until VB2A and VB2B are relatively close, and then the two earphone batteries are charged at the same time until VB2A and VB2B are both charged to the maximum value of 4.43V. It should also be noted that, if VB1 is equal to the minimum value between VB2A and VB2B, charging can also be performed in a method in which VB1 is less than the minimum value between VB2A and VB2B.

[0054] Assume that before charging, the control unit 5 obtains the voltage VB2A=4.1V of the first earphone battery B2A, the voltage VB2B=3.5V of the second earphone battery B2B, and the voltage VB1=4V of the earphone box battery B1 (that is, the earphone box battery terminal O1). At this time, the earphone box charging terminal O3 is in a non-plugged state, and VB2B<VB1<VB2A. At this time, the control voltage conversion circuit 4 operates in a battery power pass-through mode to charge the two earphone batteries until VB1=VB2B. The control voltage conversion circuit 4 operates in a battery power boost mode. In this process, the voltage conversion circuit 4 is controlled to work in the battery power boost mode. Specifically, there can be a variety of charging methods, such as directly setting the output voltage of the voltage conversion circuit 4 to 4.43V for charging, or first setting the output voltage of the voltage conversion circuit 4 to be slightly larger than VB2B, and then gradually increasing the output voltage of the voltage conversion circuit 4 until VB2A and VB2B are both charged to the maximum value of 4.43V. For example, first set the output voltage of the voltage conversion circuit 4 to VB2B+20mV for charging, VB2B gradually increases, and the current passing through the inductor L gradually decreases. When the current decreases to below the preset value, it is considered that the voltage difference between the output voltage of the voltage conversion circuit 4 and VB2B is small. At this time, increase the output voltage of the voltage conversion circuit 4, and so on. Based on the current passing through the inductor L, gradually increase the output voltage of the voltage conversion circuit 4 until VB2A and VB2B are relatively close, and then charge the two headphone batteries at the same time until VB2A and VB2B are both charged to the maximum value of 4.43V.

[0055] In a possible implementation, the voltage conversion circuit 4 further includes: a third transistor Q3, the earphone box charging terminal O3 is electrically connected to the earphone charging terminal O2 through the third transistor Q3, wherein the first end of the third transistor Q3 is electrically connected to the earphone box charging terminal O3, and the second end of the third transistor Q3 is electrically connected to the earphone charging terminal O2. The control unit 5 is electrically connected to the control end of the third transistor Q3, and the control unit 5 is also used for: if the earphone box charging terminal O3 is in a non-plugged state, controlling the third transistor Q3 to be turned off, and if the earphone box charging terminal O3 is in a plugged state, controlling the third transistor Q3 to be turned on. When the earphone box charging terminal O3 is in a non-plugged state, the third transistor Q3 is controlled to be turned off, which can improve the problem that the earphone box charging terminal O3 is charged and easily corroded. When the earphone box charging terminal O3 is in a plugged state, the third transistor Q3 is controlled to be turned on to ensure that power can be taken from the earphone box charging terminal O3 to charge the earphone box 2 or the earphone 3.

[0056] In a possible implementation, the first transistor Q1, the second transistor Q2, and the third transistor Q3 are metal-oxide-semiconductor field-effect transistors (MOSFET), wherein the first diode D1 may be a parasitic diode of the first transistor Q1, and the second diode D2 may be a parasitic diode of the second transistor Q2.

[0057] In a possible implementation, the voltage conversion circuit 4 further includes: a third diode D3, the third diode D3 is connected in parallel to the third transistor Q3, the anode of the third diode D3 is electrically connected to the first end of the third transistor Q3, and the cathode of the third diode D3 is electrically connected to the second end of the third transistor Q3. The third diode D3 may be a parasitic diode of the third transistor Q3, and the third diode D3 is used to prevent current backflow when the charging terminal O3 of the earphone box is in a plugged state.

[0058] In a possible implementation, the earphone box charging terminal O3 is a Type-C interface.

[0059] The embodiment of the present application further provides an earphone box 2, comprising the earphone box circuit 1 in the above embodiment, and the earphone box 2 further comprises an earphone box battery B1, the positive electrode of the earphone box battery B1 is electrically connected to the earphone box battery terminal O1, and the negative electrode of the earphone box battery B1 is grounded. The specific structure and principle of the earphone box 2 are the same as those in the above embodiment, and will not be repeated here.

[0060] The embodiment of the present application also provides an earphone charging system, comprising at least one wireless earphone 3 and the earphone box 2 in the above embodiment.

[0061] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0062] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An earphone box circuit, used for an earphone box of a wireless earphone, characterized in that: The earphone box circuit comprises: Headphone box battery terminal and headphone charging terminal; A voltage conversion circuit, the voltage conversion circuit comprising: A first transistor, wherein a first end of the first transistor is electrically connected to the earphone charging end; a first diode, wherein the first diode is connected in parallel to the first transistor, an anode of the first diode is electrically connected to the second end of the first transistor, and a cathode of the first diode is electrically connected to the first end of the first transistor; a second transistor, wherein a first terminal of the second transistor is electrically connected to a second terminal of the first transistor, and a second terminal of the second transistor is grounded; an inductor, the inductor being connected in series between the second end of the first transistor and a battery end of the earphone box; A first capacitor, the first capacitor is connected in series between the earphone charging terminal and a ground point; The voltage conversion circuit is at least used to work in a battery-powered boost mode. In the battery-powered boost mode, the first transistor is turned off and the second transistor works in an alternate on and off state, so that the first diode, the second transistor, the inductor and the capacitor form a boost circuit with the battery end of the earphone box as the input end and the earphone charging end as the output end; The voltage conversion circuit further includes: a third transistor, the earphone box charging end is electrically connected to the earphone charging end through the third transistor, wherein a first end of the third transistor is electrically connected to the earphone box charging end, and a second end of the third transistor is electrically connected to the earphone charging end; The earphone box circuit further includes a control unit, which is electrically connected to the control end of the third transistor and is used for: Obtaining the connection status of the charging terminal of the earphone box; If the charging terminal of the earphone box is in a non-plugged state, controlling the third transistor to be turned off; If the charging end of the earphone box is in a plugged-in state, the third transistor is controlled to be turned on.

2. The earphone box circuit according to claim 1, characterized in that: The voltage conversion circuit further includes: An earphone box charging terminal, the earphone box charging terminal being electrically connected to the earphone charging terminal; a second diode, the second diode being connected in parallel to the second transistor, an anode of the second diode being electrically connected to the second end of the second transistor, and a cathode of the second diode being electrically connected to the first end of the second transistor; A second capacitor, which is connected in series between the battery terminal of the earphone box and a ground point; The voltage conversion circuit is also used to operate in a charging terminal power supply mode. In the charging terminal power supply mode, the first transistor operates in alternating on and off states, and the second transistor is cut off, so that the second diode, the first transistor, the inductor and the second capacitor form a step-down circuit with the earphone charging terminal as the input terminal and the earphone box battery terminal as the output terminal.

3. The earphone box circuit according to claim 1 or 2, characterized in that: The voltage conversion circuit is also used to operate in a battery power supply direct mode. In the battery power supply direct mode, the first transistor is turned on and the second transistor is turned off.

4. The earphone box circuit according to claim 3, characterized in that: The control unit is electrically connected to the control end of the first transistor and the control end of the second transistor, and the control unit is used for: Acquire the voltage of the earphone battery of the wireless earphone connected to the earphone box circuit, and acquire the voltage of the battery terminal of the earphone box; The voltage conversion circuit is controlled to operate in the battery power-taking boost mode or the battery power-taking direct mode according to the voltage relationship between the battery terminal of the earphone box and the earphone battery of the wireless earphone.

5. The earphone box circuit according to claim 4, characterized in that: The process of controlling the voltage conversion circuit to operate in the battery power boost mode or the battery power pass-through mode according to the voltage relationship between the battery terminal of the earphone box and the earphone battery of the wireless earphone comprises: If the voltage at the battery end of the earphone box is lower than the voltage of the earphone battery of the wireless earphone, the voltage conversion circuit is controlled to operate in the battery power taking and voltage boosting mode; If the voltage at the battery end of the earphone box is greater than the voltage of the earphone battery of the wireless earphone, the voltage conversion circuit is controlled to operate in the battery power pass-through mode.

6. The earphone box circuit according to claim 2, characterized in that: The control unit is electrically connected to the control end of the first transistor and the control end of the second transistor, and the control unit is used for: Acquire the connection status of the charging terminal of the earphone box, acquire the voltage of the earphone battery of the wireless earphone connected to the earphone box circuit, and acquire the voltage of the battery terminal of the earphone box; According to the connection state of the charging end of the earphone box, the voltage of the earphone battery of the wireless earphone and the voltage of the battery end of the earphone box, the voltage conversion circuit is controlled to work in the battery power taking boost mode or the charging end power taking mode.

7. The earphone box circuit according to claim 6, characterized in that: The process of controlling the voltage conversion circuit to operate in the battery power taking boost mode or the charging end power taking mode according to the connection state of the charging end of the earphone box, the voltage of the earphone battery of the wireless earphone, and the voltage of the battery end of the earphone box includes: If the charging terminal of the earphone box is in a non-plugged state, and the voltage of the battery terminal of the earphone box is lower than the voltage of the earphone battery of the wireless earphone, the voltage conversion circuit is controlled to operate in the battery power taking boost mode; If the charging end of the earphone box is in a plugged-in state, the voltage conversion circuit is controlled to operate in a power-taking mode of the charging end.

8. The earphone box circuit according to claim 1, characterized in that: The control unit is also used for: If the charging end of the earphone box is in a non-plugged state and the voltage at the battery end of the earphone box is greater than the voltage of the earphone battery of the wireless earphone, the voltage conversion circuit is controlled to operate in a battery power pass-through mode. In the battery power pass-through mode, the first transistor is turned on and the second transistor is turned off.

9. The earphone box circuit according to claim 8, characterized in that: The wireless earphone electrically connected to the earphone box comprises a first earphone and a second earphone, the first earphone comprises a first earphone battery, and the second earphone comprises a second earphone battery; If the charging terminal of the earphone box is in a non-plugged state and the voltage of the battery terminal of the earphone box is greater than the voltage of the earphone battery of the wireless earphone, the process of controlling the voltage conversion circuit to operate in a battery power pass-through mode includes: If the charging terminal of the earphone box is in a non-plugged state, and the voltage of the battery terminal of the earphone box is greater than the maximum value of the voltage of the first earphone battery and the voltage of the second earphone battery, control the voltage conversion circuit to operate in the battery power pass-through mode; If the charging terminal of the earphone box is in a non-plugged state and the voltage of the battery terminal of the earphone box is lower than the voltage of the earphone battery of the wireless earphone, the process of controlling the voltage conversion circuit to operate in the battery power taking boost mode includes: If the charging terminal of the earphone box is in a non-plugged state, and the voltage of the battery terminal of the earphone box is less than the minimum value of the voltage of the first earphone battery and the voltage of the second earphone battery, control the voltage conversion circuit to operate in the battery power taking boost mode; The control unit is also used for: If the charging terminal of the earphone box is in a non-plugged state, and the voltage at the battery terminal of the earphone box is between the voltage of the first earphone battery and the voltage of the second earphone battery, the voltage conversion circuit is controlled to operate in the battery power pass-through mode until the voltage at the battery terminal of the earphone box is equal to the minimum value of the voltage of the first earphone battery and the voltage of the second earphone battery, and the voltage conversion circuit is controlled to operate in the battery power boost mode.

10. The earphone box circuit according to claim 9, characterized in that: The control unit is also used to obtain the current passing through the inductor in the battery power taking boost mode, and control the voltage conversion circuit to operate in the battery power taking boost mode based on the output voltage, the output voltage is greater than the minimum value of the voltage of the first earphone battery and the voltage of the second earphone battery, and when the current passing through the inductor is less than a preset value, the output voltage is increased.

11. The earphone box circuit according to claim 2, characterized in that: The first transistor, the second transistor and the third transistor are metal-oxide semiconductor field effect transistors.

12. The earphone box circuit according to claim 1, characterized in that: The voltage conversion circuit also includes: a third diode, the third diode is connected in parallel to the third transistor, the anode of the third diode is electrically connected to the first end of the third transistor, and the cathode of the third diode is electrically connected to the second end of the third transistor.

13. The earphone box circuit according to claim 2, characterized in that: The charging end of the earphone box is a Type-C interface.

14. An earphone box, characterized in that: The invention comprises an earphone box circuit as claimed in any one of claims 1 to 13.

15. An earphone charging system, characterized in that: The invention comprises at least one wireless earphone and the earphone box as claimed in claim 14.

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