Wireless earphones and circuits thereof, charging case and circuits thereof, charging system and method

Abstract

The present invention relates to a wireless headset and its circuit, a charging compartment and its circuit, a charging system, and a charging method. The wireless headset circuit includes a feedback unit, a first battery connected in series between a first ground terminal and a first voltage terminal, and a voltage-dividing resistor. The first voltage terminal and the first ground terminal can be disconnectably connected to the charging compartment circuit. The feedback unit is used to feedback the first voltage value of the first battery or the function value with the first voltage value of the first battery as a variable to the charging compartment circuit, so that the charging compartment circuit can provide a charging voltage based on the sum of the first voltage value and the voltage drop of the set voltage-dividing resistor during charging. The present invention can improve charging efficiency, reduce energy loss, and simplify the wireless headset circuit, which is conducive to reducing the size and cost of wireless headsets using the circuit.

Description

Technical Field

[0001] The present invention relates to the field of earphone technology, and in particular to a wireless earphone and its circuit, a charging compartment and its circuit, a charging system and method. Background Art

[0002] Compared to wired headphones, wireless headphones are more portable and therefore increasingly popular. However, existing true wireless stereo (TWS) headphones suffer from low charging efficiency and high energy loss during charging. Furthermore, the complex circuit design within wireless headphones results in a larger size and higher cost. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above-mentioned technical problems and provide a wireless headset and its circuit, a charging case and its circuit, a charging system and method, which can improve charging efficiency, reduce energy loss, and simplify the circuit structure in the wireless headset, which is conducive to reducing the size of the wireless headset and reducing costs.

[0004] In order to achieve the above-mentioned objectives, on the one hand, the present invention provides a wireless headset circuit, including a feedback unit, a first battery and a voltage divider resistor connected in series between a first ground terminal and a first voltage terminal, the first voltage terminal and the first ground terminal can be disconnected from the charging compartment circuit, and the feedback unit is used to feedback the first voltage value of the first battery or the function value with the first voltage value of the first battery as a variable to the charging compartment circuit, so that the charging compartment circuit can provide a charging voltage according to the sum of the first voltage value and the voltage drop of the set voltage divider resistor during charging.

[0005] Optionally, the feedback unit includes an analog-to-digital converter connected to the first battery, and the analog-to-digital converter is used to output the first voltage value of the first battery, wherein: the analog-to-digital converter is connected to the charging compartment circuit during charging, so as to feed back the first voltage value to the charging compartment circuit; or, the feedback unit also includes a first wireless communication unit connected to the analog-to-digital converter, and the first wireless communication unit can communicate with a second wireless communication unit of the charging compartment circuit to feed back the first voltage value to the charging compartment circuit.

[0006] Optionally, the feedback unit includes a setting unit, an adder and an analog-to-digital converter connected to the first battery, the analog-to-digital converter is used to output the first voltage value of the first battery, the setting unit is used to set the second voltage value, the second voltage value represents the voltage drop of the charging current on the voltage divider resistor, and the adder is used to calculate the sum of the first voltage value and the second voltage value, wherein: the adder is connected to the charging compartment circuit during charging to feed back the sum of the first voltage value and the second voltage value to the charging compartment circuit; or, the feedback unit also includes a first wireless communication unit connected to the adder, and the first wireless communication unit can communicate with the second wireless communication unit of the charging compartment circuit to feed back the voltage value calculated by the adder to the charging compartment circuit.

[0007] A second aspect of the present invention provides a wireless headset, comprising the wireless headset circuit described in the first aspect.

[0008] The third aspect of the present invention provides a charging compartment circuit, comprising a voltage regulating unit, a second battery, and a charging management unit connected to the second battery for charging management of the second battery. The output end and the second ground end of the voltage regulating unit can be disconnectably connected to the wireless headset circuit, and the voltage regulating unit can adjust the first voltage input by the second battery to a second voltage according to the total voltage value and then output it to charge the first battery of the wireless headset circuit. The total voltage value is: the sum of the second voltage value set by the charging compartment circuit and the first voltage value fed back by the wireless headset circuit; or the function value fed back by the wireless headset circuit with the first voltage value as a variable; and wherein: the absolute value of the second voltage is greater than or equal to the first voltage; or, the absolute value of the second voltage is less than or equal to the first voltage.

[0009] Optionally, the charging compartment circuit further includes a setting unit and an adder, the setting unit being used to set the second voltage value, the second voltage value representing the voltage drop of the charging current on the voltage divider resistor connected in series with the first battery in the wireless headset circuit, the adder being capable of receiving the first voltage value of the first battery fed back by the wireless headset circuit to calculate the sum of the first voltage value and the second voltage value as the total voltage value to output to the voltage regulation unit, wherein: the adder is connected to the wireless headset circuit during charging to receive the first voltage value; or, the charging compartment circuit further includes a second wireless communication unit connected to the adder, the second wireless communication unit being capable of communicating with the first wireless communication unit of the wireless headset circuit so that the adder receives the first voltage value fed back by the wireless headset circuit.

[0010] Optionally, the voltage regulating unit is capable of receiving the total voltage value fed back by the wireless headset circuit, wherein: the voltage regulating unit is connected to the wireless headset circuit during charging to receive the total voltage value; or, the charging compartment circuit also includes a second wireless communication unit connected to the voltage regulating unit, and the second wireless communication unit is capable of communicating with the first wireless communication unit of the wireless headset circuit so that the voltage regulating unit receives the total voltage value fed back by the wireless headset circuit.

[0011] Optionally, the voltage regulation unit includes a digital-to-analog conversion module and a regulation module connected to the digital-to-analog conversion module, the digital-to-analog conversion module can convert the received voltage value into an analog voltage signal and output it to the regulation module, the regulation module adjusts the first voltage to the second voltage according to the analog voltage signal and outputs it, the voltage value received by the digital-to-analog conversion module is equal to the value of the second voltage, wherein: the voltage value received by the digital-to-analog conversion module is the total voltage value; or, the charging compartment circuit further includes a selection unit that receives the total voltage value, when the first battery is charged with a constant current, the selection unit outputs the total voltage value to the digital-to-analog conversion module; when the first battery is charged with a constant voltage, the selection unit outputs a first reference voltage value to the digital-to-analog conversion module, and the first reference voltage value represents the voltage value required by the wireless headset circuit when the first battery is charged with a constant voltage.

[0012] Optionally, the regulation module includes a first switch connected in series between the second battery and the output end of the voltage regulation unit, an inductor and a capacitor, a second switch connected in parallel with the inductor and the capacitor, a first resistor and a second resistor connected in series between the output end of the digital-to-analog conversion module and the output end of the voltage regulation unit, a control circuit and an error amplifier, the first output end of the control circuit is connected to the first switch for controlling the conduction and closing of the first switch, the second output end of the control circuit is connected to the second switch for controlling the conduction and closing of the second switch, the positive input end of the error amplifier is connected between the first resistor and the second resistor, the negative input end of the error amplifier is connected to the second ground end between the inductor and the capacitor, and the output end of the error amplifier is connected to the input end of the control circuit, wherein: when the first switch is closed, the second switch is open When the first switch is opened, the inductor stores energy; when the first switch is disconnected, the second switch is closed, and the inductor releases energy, so that the output end of the voltage regulating unit outputs the second voltage; and / or, the digital-to-analog conversion module includes an operational amplifier, a third resistor connected between the second voltage end and the second ground end, and a plurality of series resistors connected between the second voltage end and the third voltage end, the third voltage end is the output end of the digital-to-analog conversion module, and each of the series resistors is connected in parallel with a control switch, the digital-to-analog conversion module includes a plurality of input ends for receiving voltage values, and the plurality of input ends are connected one-to-one with the plurality of control switches to control the conduction and closing of the corresponding control switches, the output end of the operational amplifier is connected to the third voltage end, the positive input end of the operational amplifier is connected to the second reference voltage, and the negative input end of the operational amplifier is connected to the second voltage end.

[0013] A fourth aspect of the present invention provides a charging compartment, comprising the charging compartment circuit described in the third aspect.

[0014] The fifth aspect of the present invention provides a charging system, which includes the wireless headset circuit described in the first aspect and the charging compartment circuit described in the third aspect, wherein one of the wireless headset circuit and the charging compartment circuit includes a setting unit and an adder.

[0015] The sixth aspect of the present invention provides a charging method, which includes: measuring the total voltage value required to charge the first battery of the wireless headset circuit; adjusting the first voltage output by the second battery of the charging compartment circuit to a second voltage according to the total voltage value, and outputting it to the wireless headset circuit to charge the first battery, and the value of the second voltage is equal to the total voltage value; wherein: the absolute value of the second voltage is greater than or equal to the first voltage; or, the absolute value of the second voltage is less than or equal to the first voltage.

[0016] In the above technical solution, since the feedback unit of the wireless headset circuit can feed back the first voltage value of the first battery to the charging compartment circuit, the charging compartment circuit can set the voltage values ​​of other components connected to the first battery of the wireless headset, for example, set the voltage drop of the voltage divider resistor during charging, and the charging compartment circuit can calculate the sum of the first voltage value and the set voltage drop value of the voltage divider resistor during charging as the voltage value required for charging the wireless headset circuit, or the feedback unit of the wireless headset circuit can feed back a function value with the first voltage value of the first battery as a variable to the charging compartment circuit, for example, the sum of the first voltage value of the first battery and the set voltage drop value of the voltage divider resistor during charging, so that the charging compartment circuit can provide a charging voltage according to the voltage value required for charging the wireless headset circuit, thereby reducing energy loss and improving charging efficiency, and the wireless headset circuit does not need to set a charging management circuit to perform charging management on the first battery such as constant current charging or constant voltage charging, which simplifies the circuit structure in the wireless headset, which is conducive to reducing the volume of the wireless headset and reducing costs.

[0017] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 This is a structural diagram of a wireless headset charging circuit;

[0020] Figure 2 A schematic diagram of the structure of a wireless headset circuit provided in an embodiment of the present application;

[0021] Figure 3 A schematic diagram of the structure of the charging compartment circuit provided in the first embodiment of the present application;

[0022] Figure 4 This is a schematic diagram of the circuit structure of the voltage regulating unit of the charging compartment circuit according to an embodiment of the present application;

[0023] Figure 5 A schematic diagram of the structure of the charging compartment circuit provided in the second embodiment of the present application;

[0024] Figure 6 A schematic structural diagram of a charging system provided in the first embodiment of the present application;

[0025] Figure 7 This is a schematic structural diagram of the charging system provided in the second embodiment of the present application. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] Figure 1 This is a schematic diagram of the structure of a wireless headset charging circuit. Figure 1 As shown, the wireless headset charging circuit consists of the following two circuits: the first circuit 10, as shown Figure 1 As shown in the right dotted box in the figure, it is located in the wireless headset and includes a first battery BAT1, at least one complete charging management unit Charger1 and a setting unit Set; the second circuit 20, as shown in the figure Figure 1 As shown in the dotted box on the left, it is located in the charging compartment and includes a second battery BAT2, a charging management unit Charger2 and a boost unit Boost. Among them, the charging management unit Charger2 in the charging compartment realizes the function of constant current charging of the second battery BAT2 in the charging compartment, and the function of the boost unit Boost is to increase the input voltage of the second battery BAT2 to 5V and then output it, that is, the voltage of VCHG is 5V. The charging management unit Charger1 in the wireless headset charges the first battery BAT1 through a 5V voltage. The setting unit Set sets the charging management unit Charger1 to set the constant current charging current of the charging management unit Charger1. Figure 1 The wireless headset shown may also be integrated with a radio frequency unit RF and an analog-to-digital conversion unit ADC. The radio frequency unit RF is used to pick up sound, while the analog-to-digital conversion unit ADC is used to monitor power. However, these units generally do not affect the charging status of the first battery BAT1.

[0028] Therefore, when the boost unit Boost outputs a 5V voltage and the voltage of the first battery BAT1 is lower, the charging efficiency is very low and energy loss is large. For example, when the voltage of the first battery BAT1 is 3V, the efficiency is 3 / 5 = 60%. In addition, the circuit design within the wireless headset is relatively complex and occupies a large space, which is not conducive to reducing the size and cost of the wireless headset.

[0029] In view of this, the embodiments of the present application provide a wireless headset and its circuit, a charging case and its circuit, a charging system and method, which can improve charging efficiency and reduce energy loss. The circuit structure inside the wireless headset is simple, which is conducive to reducing the size of the wireless headset and reducing costs.

[0030] Figure 2 This is a schematic diagram of the structure of the wireless headset circuit provided in the embodiment of the present application. Figure 2 As shown, the wireless headset circuit includes a feedback unit F, a first battery BAT1 connected in series between a first ground terminal GND1 and a first voltage terminal VCHG, and a voltage-dividing resistor R. The first voltage terminal VCHG and the first ground terminal GND1 can be disconnectably connected to the charging compartment circuit. The feedback unit F is used to feedback the first voltage value of the first battery BAT1 or the function value with the first voltage value of the first battery BAT1 as a variable to the charging compartment circuit, so that the charging compartment circuit can provide a charging voltage according to the sum of the first voltage value and the voltage drop of the set voltage-dividing resistor R during charging. The feedback unit F can have but is not limited to the following two situations:

[0031] The first case

[0032] The feedback unit F includes an analog-to-digital converter ADC connected to the first battery BAT1, and the analog-to-digital converter ADC is used to output the first voltage value of the first battery BAT1. In addition, the feedback unit F can feedback the voltage value to the charging compartment circuit in a wired manner. That is, the analog-to-digital converter ADC can be connected to the charging compartment circuit during charging, so as to feedback the first voltage value to the charging compartment circuit. Alternatively, the feedback unit F can feedback the voltage value to the charging compartment circuit in a wireless manner. Specifically, the feedback unit F may also include a first wireless communication unit connected to the analog-to-digital converter ADC, for example, a first radio frequency unit RF1, and the first wireless communication unit can communicate with the second wireless communication unit of the charging compartment circuit to feedback the first voltage value to the charging compartment circuit.

[0033] Second case

[0034] like Figure 2As shown, the feedback unit F includes a setting unit Set, an adder Adder, and an analog-to-digital converter ADC connected to the first battery BAT1. The analog-to-digital converter ADC is used to output a first voltage value of the first battery BAT1. The setting unit Set is used to set a second voltage value, which represents the voltage drop across the voltage divider resistor R caused by the charging current. The adder Adder is used to calculate the sum of the first and second voltage values. Furthermore, the feedback unit F can use a wired method to feed back the voltage value to the charging compartment circuit. That is, the adder Adder is connected to the charging compartment circuit during charging to feed back the sum of the first and second voltage values ​​to the charging compartment circuit. Alternatively, the feedback unit F can use a wireless method to feed back the voltage value to the charging compartment circuit. Specifically, the feedback unit F also includes a first wireless communication unit connected to the adder Adder, such as a first radio frequency unit RF1. The first wireless communication unit can communicate with a second wireless communication unit of the charging compartment circuit to feed back the voltage value calculated by the adder to the charging compartment circuit.

[0035] In the above technical solution, since the feedback unit F of the wireless headset circuit can feed back the first voltage value of the first battery BAT1 to the charging compartment circuit, the charging compartment circuit can set the voltage drop of the voltage divider resistor R during charging, and the charging compartment circuit can calculate the sum of the first voltage value and the set voltage drop value of the voltage divider resistor R during charging as the voltage value required for charging the wireless headset circuit, or the feedback unit F of the wireless headset circuit can feed back a function value with the first voltage value of the first battery BAT1 as a variable to the charging compartment circuit, for example, the sum of the first voltage value of the first battery BAT1 and the set voltage drop value of the voltage divider resistor R during charging, so that the charging compartment circuit can provide a charging voltage according to the voltage value required for charging the wireless headset circuit, thereby reducing energy loss and improving charging efficiency. Moreover, when charging, the wireless headset circuit does not need to set a charging management circuit to perform charging management on the first battery BAT1 such as constant current charging or constant voltage charging, thereby simplifying the circuit structure in the wireless headset, which is conducive to reducing the volume of the wireless headset and reducing costs.

[0036] In addition, an embodiment of the present invention further provides a wireless headset, which includes the above-mentioned wireless headset circuit.

[0037] Figure 3 This is a schematic diagram of the structure of the charging compartment circuit provided in the first embodiment of the present application. Figure 3As shown, the charging compartment circuit includes a voltage regulating unit Buck-Boost, a second battery BAT2 and a charging management unit Charger connected to the second battery BAT2 for charging management of the second battery BAT2. The output end and the second ground end GND2 of the voltage regulating unit Buck-Boost can be disconnectably connected to the wireless headset circuit, and the voltage regulating unit Buck-Boost can adjust the first voltage input by the second battery BAT2 to a second voltage according to the total voltage value and then output it to charge the first battery BAT1 of the wireless headset circuit. The total voltage value is: the sum of the second voltage value set by the charging compartment circuit and the first voltage value fed back by the wireless headset circuit; or the function value fed back by the wireless headset circuit with the first voltage value as the variable, for example, the function value is the sum of the first voltage value and the voltage drop of the voltage divider resistor R set by the wireless headset circuit during charging, and wherein: the absolute value of the second voltage is greater than or equal to the first voltage; or, the absolute value of the second voltage is less than or equal to the first voltage.

[0038] Furthermore, in order to simplify the wireless headset circuit, reduce the size of the wireless headset and reduce the cost, the charging compartment circuit may further include a setting unit Set and an adder Adder (not shown). Figure 3 As shown in Figure 2 ), the setting unit Set is used to set a second voltage value, which represents the voltage drop of the charging current across the voltage divider resistor R connected in series with the first battery BAT1 in the wireless headset circuit. The adder Adder can receive the first voltage value of the first battery BAT1 fed back by the wireless headset circuit to calculate the sum of the first voltage value and the second voltage value, and output it as the total voltage value to the voltage regulation unit Buck-Boost. In addition, the adder Adder can receive the first voltage value fed back by the wireless headset circuit in a wired manner. That is, the adder Adder is connected to the wireless headset circuit during charging to receive the first voltage value. Alternatively, the adder Adder can receive the first voltage value fed back by the wireless headset circuit in a wireless manner. Specifically, the charging compartment circuit also includes a second wireless communication unit connected to the adder Adder, for example, a second radio frequency unit RF2. The second wireless communication unit can communicate with the first wireless communication unit of the wireless headset circuit so that the adder Adder receives the first voltage value fed back by the wireless headset circuit.

[0039] Alternatively, in order to enable the charging compartment circuit to adapt to the charging requirements of different wireless headset circuits, optionally, the voltage regulating unit Buck-Boost receives the function value with the first voltage value as the variable fed back by the wireless headset circuit as the total voltage value. That is, the voltage regulating unit Buck-Boost can receive the total voltage value fed back by the wireless headset circuit. Moreover, the voltage regulating unit Buck-Boost can receive the total voltage value fed back by the wireless headset circuit in a wired manner. That is, the voltage regulating unit Buck-Boost is connected to the wireless headset circuit during charging to receive the total voltage value. Or the voltage regulating unit Buck-Boost can receive the total voltage value fed back by the wireless headset circuit in a wireless manner. Specifically, if Figure 3 As shown, the charging case circuit also includes a second wireless communication unit connected to the voltage regulating unit Buck-Boost, for example, a second radio frequency unit RF2. The second wireless communication unit can communicate with the first wireless communication unit of the wireless headset circuit so that the voltage regulating unit Buck-Boost receives the total voltage value fed back by the wireless headset circuit.

[0040] Figure 4 Schematic diagram of the circuit structure of the voltage regulating unit of the charging compartment circuit of the embodiment of the present application. Figure 4 As shown, the voltage regulation unit Buck-Boost may include a digital-to-analog conversion module 1 and a regulation module 2 connected to the digital-to-analog conversion module 1. The digital-to-analog conversion module 1 can convert the received voltage value into an analog voltage signal and output it to the regulation module. The regulation module 2 adjusts the first voltage to a second voltage according to the analog voltage signal and outputs it. The voltage value received by the digital-to-analog conversion module 1 is equal to the value of the second voltage, wherein the voltage value received by the digital-to-analog conversion module 1 is the total voltage value.

[0041] Figure 5 This is a schematic diagram of the structure of the charging compartment circuit provided in the second embodiment of the present application. Figure 3 and Figure 5 As shown, in Figure 3 Based on the charging chamber circuit of the first embodiment shown, Figure 5 The charging compartment circuit of the second embodiment shown also includes a selection unit Min for receiving a total voltage value. When the first battery BAT1 is charged with a constant current, the selection unit Min outputs the total voltage value to the digital-to-analog conversion module 1; when the first battery is charged with a constant voltage, the selection unit Min outputs the first reference voltage value VDRef1 to the digital-to-analog conversion module 1. The first reference voltage value VDRef1 represents the voltage value required by the wireless headset circuit when the first battery BAT1 is charged with a constant voltage.

[0042] Continue to refer Figure 4The regulation module 2 includes a first switch K1 connected in series between the second battery BAT2 and the output terminal VO of the voltage regulation unit Buck-Boost, an inductor L1 connected in series with the first switch K1, a second switch K2 between the inductor L1 and the output terminal of the voltage regulation unit Buck-Boost, a capacitor C1 connected to one end of the second switch K2, a control circuit for controlling the first switch K1 and the second switch K2, an error amplifier EA, and a first resistor R1 and a second resistor R2 connected in series between the output terminal of the digital-to-analog conversion module 1 and the output terminal of the voltage regulation unit Buck-Boost. A first output terminal of the control circuit is connected to the first switch K1 for controlling the conduction and closing of the first switch K1, and a second output terminal of the control circuit is connected to the second switch K2 for controlling the conduction and closing of the second switch K2. A positive input terminal of the error amplifier EA is connected between the first resistor R1 and the second resistor R2, and a negative input terminal of the error amplifier EA is connected to the second ground terminal GND2 between the inductor L1 and the capacitor C1. An output terminal of the error amplifier EA is connected to an input terminal of the control circuit, wherein: when the first switch K1 is closed, the second switch K2 is opened, and the inductor L1 stores energy; when the first switch K1 is opened, the second switch K2 is closed, and the inductor L1 releases energy, so that the output terminal VO of the voltage regulation unit Buck-Boost outputs a second voltage.

[0043] The digital-to-analog conversion module 1 includes an operational amplifier OP, a third resistor R3 connected between the second voltage terminal V2 and the second ground terminal GND2, and a plurality of series resistors R4, R5, R6, and R7 connected between the second voltage terminal V2 and the third voltage terminal V1. The third voltage terminal V1 is the output terminal of the digital-to-analog conversion module 1. A control switch KA, KB, and KC are connected in parallel to each of the series resistors R4, R5, R6, and R7. The digital-to-analog conversion module 1 includes a plurality of input terminals for receiving voltage values. The plurality of input terminals are connected one-to-one to the plurality of control switches KA, KB, and KC for controlling the conduction and closing of the corresponding control switches. The output terminal of the operational amplifier OP is connected to the third voltage terminal V1, the positive input terminal of the operational amplifier OP is connected to the second reference voltage VRef2, and the negative input terminal of the operational amplifier OP is connected to the third voltage terminal V1.

[0044] In addition, an embodiment of the present invention further provides a charging compartment, comprising the above-mentioned charging compartment circuit.

[0045] Figure 6 This is a schematic diagram of the structure of the charging system provided in the first embodiment of the present application. Figure 6As shown, the wireless headset charging circuit includes a first circuit 100 disposed within the wireless headset and a second circuit 200 disposed within the charging compartment. The first circuit 100 includes an analog-to-digital converter (ADC), a first battery BAT1, and a voltage divider resistor R connected in series between a first ground terminal GND1 and a first voltage terminal VCHG. The analog-to-digital converter ADC is connected to the first battery BAT1 to output a first voltage value of the first battery BAT1. The second circuit 200 includes a voltage regulator unit (Buck-Boost), a second battery BAT2, and a charge management unit (Charger) connected to the second battery BAT2 for charging management of the second battery BAT2. One of the output terminal VO of the voltage regulator unit and the second ground terminal GND2 is connected to the first ground terminal GND1, and the other of the output terminal VO of the voltage regulator unit and the second ground terminal GND2 is connected to the first voltage terminal VCHG. The wireless headset charging circuit also includes a setting unit Set and an adder Adder arranged in the wireless headset or charging case. The setting unit Set is used to set a second voltage value. The second voltage value represents the voltage value applied to the voltage divider resistor R when the first battery BAT1 is constantly charged with a constant current, that is, the voltage drop of the charging current on the voltage divider resistor R. The adder Adder is used to calculate the sum of the first voltage value and the second voltage value. The voltage adjustment unit Buck-Boost is used to adjust the first voltage input from the second battery BAT2 to the second voltage according to the voltage value calculated by the adder Adder, and then output it to charge the first battery BAT1.

[0046] The voltage divider resistor R can be set outside the chip, such as a resistor mounted on a printed circuit board, or it can be integrated inside the chip, for example, using a metal resistor or a polysilicon resistor. The circuit of the setting unit Set can be designed by a digital circuit, such as a Verilog language design and synthesis, which may include some registers to store the resistance value of the voltage divider resistor R, the charging current value, etc. and perform simple operations. For example, the resistance value of the voltage divider resistor R and the charging current value are multiplied and output to the adder Adder. In some designs, the resistance value of the voltage divider resistor R can be rewritten by software, and the charging current value can also be designed to be rewritten by software.

[0047] In addition, the first voltage terminal VCHG is connected to the positive electrode of the first battery BAT1, and the first ground terminal GND1 is connected to the negative electrode of the first battery BAT1. The second voltage output by the output terminal of the voltage regulating unit can be a positive voltage. In this case, the output terminal of the voltage regulating unit is connected to the first voltage terminal VCHG, and the second ground terminal GND2 is connected to the first ground terminal GND1. However, to simplify the circuit structure and reduce costs, the second voltage output by the output terminal VO of the voltage regulating unit can be a negative voltage. The output terminal VO of the voltage regulating unit is connected to the first ground terminal GND1, and the second ground terminal GND2 is connected to the first voltage terminal VCHG. Furthermore, in both cases where the second voltage output by the output terminal VO of the voltage regulating unit is a negative voltage or a positive voltage, the absolute value of the second voltage can be greater than or equal to the first voltage, or the absolute value of the second voltage can be less than or equal to the first voltage. In other words, the voltage regulating unit can adjust the input voltage of the second battery BAT2 up or down before outputting it to charge the first battery BAT1. The voltage regulating unit can be a buck-boost circuit.

[0048] Since the first circuit 100 provided in the wireless headset includes an analog-to-digital converter ADC and a first battery BAT1 and a voltage divider resistor R connected in series between the first ground terminal GND1 and the first voltage terminal VCHG, the analog-to-digital converter ADC can output a first voltage value of the first battery BAT1. The setting unit Set is used to set a second voltage value, which represents the voltage value applied to the voltage divider resistor R when the first battery BAT1 is constantly charged. The adder Adder can calculate the sum of the first voltage value and the second voltage value. The voltage adjustment unit Buck-Boost can adjust the first voltage input from the second battery BAT2 to the second voltage according to the voltage value calculated by the adder Adder and output it to charge the first battery BAT1. That is, when charging the wireless headset, the second circuit 200 in the charging compartment can output the charging voltage required by the first circuit 100 in the wireless headset according to the voltage value calculated by the adder Adder, thereby reducing energy loss and improving charging efficiency. In addition, the circuit structure in the wireless headset is simple, which is conducive to reducing the size and cost of the wireless headset.

[0049] In which case, when the setting unit Set and the adder Adder are located in the wireless headset, when the wireless headset is charged using the charging compartment, the voltage regulating unit Buck-Boost can be connected to the adder Adder by wire, so that the first voltage input from the second battery BAT2 is adjusted to the second voltage according to the voltage value calculated by the adder Adder and then output. Alternatively, the wireless headset charging circuit may further include a first wireless communication unit provided in the wireless headset and a second wireless communication unit provided in the charging compartment. Moreover, the wireless communication method between the first wireless communication unit and the second wireless communication unit may be one of radio frequency, Bluetooth, WiFi and ZigBee. Figure 6 As shown, the adder Adder is connected to the first wireless communication unit, such as the radio frequency unit RF1, and the voltage regulation unit Buck-Boost is connected to the second wireless communication unit, such as the radio frequency unit RF2, so as to receive the voltage value calculated by the adder Adder through wireless communication between the first wireless communication unit and the second wireless communication unit.

[0050] Figure 7 This is a schematic diagram of the structure of the charging system provided in the second embodiment of the present application. Figure 7 As shown, to implement constant-current or constant-voltage charging of the first battery BAT1, the wireless headset charging circuit may further include a selection unit Min. If the voltage value calculated by the adder Adder is less than a first reference voltage value VDRef1, the selection unit Min outputs the voltage value calculated by the adder Adder, and constant-current charging of the first battery BAT1 is performed. The first reference voltage value VDRef1 represents the charging voltage value required by the voltage divider resistor R and the first battery BAT1 for constant-voltage charging of the first battery BAT1. If the voltage value calculated by the adder Adder is greater than the first reference voltage value VDRef1, the selection unit Min outputs the first reference voltage value VDRef1, and constant-voltage charging of the first battery BAT1 is performed.

[0051] Continue to refer Figure 7 VDRef1[2:0] and VDRF2[2:0] have the same number of bits, both being three-digit digital signals. VDRef1[2:0] represents the constant voltage value for constant voltage charging, for example, 4.2V. When VDRF2[2:0] is greater than VDRef1[2:0], the selection unit Min selects the value of VDRef1[2:0] and outputs it to VD[2:0] to control the output voltage of the Buck-Boost. When VDRF2[2:0] is less than VDRef1[2:0], the selection unit Min selects the value of VDRF2[2:0] and outputs it to VD[2:0] to control the output voltage of the Buck-Boost.

[0052] It can be seen from the above content that the charging system provided by an embodiment of the present invention includes the above-mentioned wireless headset circuit and the above-mentioned charging compartment circuit, wherein one of the wireless headset circuit and the charging compartment circuit includes a setting unit Set and an adder Adder.

[0053] In addition, an embodiment of the present invention also provides a charging method, which includes: measuring the total voltage value required to charge the first battery of the wireless headset circuit; adjusting the first voltage output by the second battery of the charging compartment circuit to a second voltage according to the total voltage value, and outputting it to the wireless headset circuit to charge the first battery, wherein the value of the second voltage is equal to the total voltage value; and the absolute value of the second voltage is greater than or equal to the first voltage; or, the absolute value of the second voltage is less than or equal to the first voltage.

[0054] Reference below Figure 4 and Figure 7 The wireless headset charging circuit of the embodiment of the present application is further described, wherein the first wireless communication unit is a radio frequency unit RF1, the second wireless communication unit is a radio frequency unit RF2, and the voltage regulation unit is a Buck-Boost circuit.

[0055] like Figure 7As shown, the circuit in the dashed box on the left represents the second circuit 200 located in the charging compartment, while the circuit in the dashed box on the right represents the first circuit 100 located in the wireless headset. The second circuit 200 may include a charging management unit (Charger), a radio frequency unit (RF2), a voltage regulation unit (Buck-Boost circuit), a second battery (BAT2), and a selection unit (Min). The charging management unit (Charger) charges the second battery (BAT2), while the Buck-Boost circuit generates an appropriate output voltage based on instructions from the radio frequency unit (RF2). Because the voltage regulation unit's output voltage, as determined by the radio frequency unit (RF2), may be higher or lower than the voltage of the second battery (BAT2), a Buck-Boost circuit is required. When the desired output voltage is higher than the voltage of the second battery (BAT2), the Buck-Boost circuit operates in boost mode; when the desired output voltage is lower than the voltage of the second battery (BAT2), the Buck-Boost circuit operates in buck mode. In a wireless headset, the voltage divider resistor R is a fixed resistor with a desired fixed resistance value. The first battery BAT1 is the battery in the wireless headset. The analog-to-digital converter ADC is used to convert the voltage of the first battery BAT1 into a digital signal representing the voltage value of the first battery BAT1. The setting unit Set is used to generate a voltage value based on a set constant current charging current and output it as a digital signal. The voltage value output by the setting unit Set represents the desired voltage across the voltage divider resistor R, which is equal to the charging current value of the first battery BAT1 multiplied by the resistance of the voltage divider resistor R. The adder Adder adds the voltage value output by the analog-to-digital converter ADC to the voltage value generated by the setting unit Set, and outputs the resulting voltage value to the radio frequency unit RF1. In wireless headsets, the radio frequency unit RF1 typically complies with the Bluetooth protocol, but in principle, it can also use other wireless communication protocols, such as Wi-Fi or Zigbee. The radio frequency unit RF1 is generally a radio frequency receiver that can both transmit and receive wireless signals. The radio frequency unit RF1 can operate based on either frequency modulation or amplitude modulation. The radio frequency unit RF1 can wirelessly communicate with the radio frequency unit RF2, transmitting a digital signal of a voltage value output by the adder Adder to the radio frequency unit RF2. The radio frequency unit RF2 then outputs the voltage value calculated by the adder Adder or a first reference voltage value VDRef1 to the buck-boost circuit Buck-Boost via the selection unit Min. The first reference voltage value VDRef1 represents the charging voltage value required by the voltage divider resistor R and the first battery BAT1 during constant-voltage charging of the first battery BAT1.The buck-boost circuit Buck-Boost outputs a corresponding voltage according to the voltage value input by the selection unit Min, and its output voltage is applied between the first voltage terminal VCHG and the first ground terminal GND1. Here, the buck-boost circuit Buck-Boost preferably outputs a negative voltage, that is, VO is negative relative to the ground voltage. Therefore, the output terminal VO of the buck-boost circuit Buck-Boost is connected to the first ground terminal GND1 of the first part of the circuit 100 in the wireless headset, and the second ground terminal GND2 of the second part of the circuit 200 of the charging case is connected to the first voltage terminal VCHG of the first circuit part 100.

[0056] refer to Figure 4 , describes an implementation method of a buck-boost circuit Buck-Boost of the present application. The buck-boost circuit Buck-Boost includes an operational amplifier OP, an error amplifier EA, resistors R1, R2, R3, R4, R5, R6, R7, a control circuit, an inductor L1, a capacitor C1, switches K1, K2. K1 and K2 are alternately turned on during operation, that is, when K1 is turned on, K2 is turned off; when K1 is turned off, K2 is turned on. Assuming that the duty cycle of K1 is D, the duty cycle of K2 is 1-D, then according to the law of conservation of magnetic flux, it can be known that:

[0057] VIN·D+(1-D)VOUT=0 (that is, the sum of the magnetic flux when K1 is conducting and storing energy on the inductor L1 and the magnetic flux when K2 is conducting and releasing energy on the inductor L1 is zero)

[0058] Wherein, VIN is the voltage value of the input first voltage terminal VCHG, VOUT is the output voltage value of the output terminal VO of the buck-boost circuit Buck-Boost, and D is the duty cycle of the switch K1.

[0059] Rearranging the above equation yields: VOUT = -VIN·D / (1-D).

[0060] When D>50%, D / (1-D) is greater than 1, VOUT is in boost mode, and the absolute value of the output voltage is greater than the absolute value of the input voltage. When D<50%, D / (1-D) is less than 1, VOUT is in buck mode, and the absolute value of the output voltage is less than the absolute value of the input voltage.

[0061] Continue to refer Figure 4When the voltage at the FB node is greater than the voltage at the second ground terminal GND2, the output voltage of the error amplifier EA increases, causing the control circuit to increase the duty cycle D1 of the switching signal SW1 it outputs. SW2 is the inverted signal of SW1, so the voltage at the output terminal VO of the buck-boost circuit decreases, causing the voltage at FB to also decrease. When the voltage at the FB node is less than the voltage at the second ground terminal GND2, the output voltage of the error amplifier EA decreases, causing the control circuit to reduce the duty cycle D1 of the switching signal SW1 it outputs. SW2 is the inverted signal of SW1, so the voltage at the output terminal VO of the buck-boost circuit increases, causing the voltage at FB to also increase.

[0062] From this, we can see that the control circuit in the Buck-Boost circuit is a negative feedback circuit. When the negative feedback circuit has sufficient gain, in the steady state, the FB voltage should be equal to the voltage of the second ground terminal GND2. Therefore, in the steady state, VO = -R2·V1 / R1.

[0063] Among them, R1 is Figure 4 The resistance value of the first resistor R1 and R2 is Figure 4 The resistance value of the second resistor R2, V1 is Figure 4 The voltage value of the third voltage terminal V1.

[0064] The voltage at the third voltage terminal V1 is generated by the operational amplifier OP, the resistors R3 to R7, and the switches KA to KC, satisfying the following conditions: V1 / (Req+R3)=V2 / R3, and VRef2=V2, thus V1=(Req+R3)VRef2 / R3.

[0065] Here, Req is the equivalent resistance of all resistors connected in series between the third voltage terminal V1 and the second voltage terminal V2 (determined by the closed and open states of R4-R7 and switches KA-KC), R3 is the resistance of the third resistor R3, and the second reference voltage VRef2 is the voltage at the second voltage terminal V2. Therefore, the resistance of Req can be changed by turning the switches on or off via the VD0-VD2 signals, thereby setting the voltage value of V1. The implementation here uses three digital signals: VD0, VD1, and VD2. In actual designs, these signals can be digital signals with more bits.

[0066] In summary, the present invention has the following advantages over the prior art: First, the circuit structure design in the wireless headset is simple, so that the charging circuit occupies less space in the wireless headset, which helps to reduce the size and weight of the wireless headset, making it easier to wear and less expensive; Second, for the entire system, the energy efficiency during charging is higher. Specifically, in the case of Figure 1In the charging circuit shown, when the output voltage of the boost unit Boost is 5V and the battery voltage is low, for example, the battery voltage is 3V, the efficiency is 3 / 5=60%, and the charging efficiency is low. Figure 6 and Figure 7 In the charging system provided by the embodiment of the present application, a first circuit section 100 provided within the wireless headset is connected in series with a voltage-divider resistor R. The voltage drop across this voltage-divider resistor R can be designed to be as small as possible, thereby improving the system's energy efficiency. For example, if the resistance of the voltage-divider resistor R is designed to be 1 ohm, when the charging current is 0.1A, the voltage drop across the voltage-divider resistor R is 0.1V. When the voltage of the first battery BAT1 is 3V, the Buck-Boost output voltage is -3.1V, and the voltage applied between the first voltage terminal VCHG and the first ground terminal GND1 is 3.1V, the system efficiency is 3 / 3.1 = 96.8%. Furthermore, according to the principles of the present invention, if the resistance of the series resistor R is reduced, the efficiency can be further improved. For example, when the resistance of the series resistor R is 0.2 ohms, if the voltage of the first battery BAT1 is 3V and the charging current is 0.1A, the charging circuit of the embodiment of the present invention can control the Buck-Boost output voltage to 3+0.1*0.2=3.02V, resulting in a system efficiency of 3 / 3.02=99.3%. In addition, after improving energy utilization efficiency, the number of times the charging compartment can charge the wireless earphones after being fully charged can be increased, thereby improving user experience.

[0067] Professionals should also be further aware that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0068] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A charging compartment circuit, characterized in that: The wireless headset circuit includes a voltage regulating unit, a second battery, and a charging management unit connected to the second battery for managing charging of the second battery. The output terminal and the second ground terminal of the voltage regulating unit can be disconnected from the wireless headset circuit, and the voltage regulating unit can adjust the first voltage input by the second battery to a second voltage according to the total voltage value and output it to charge the first battery of the wireless headset circuit. The total voltage value is: the sum of the second voltage value set by the charging compartment circuit and the first voltage value fed back by the wireless headset circuit; or, the function value with the first voltage value as a variable fed back by the wireless headset circuit; and wherein: the absolute value of the second voltage is greater than or equal to the first voltage; or The absolute value of the second voltage is less than or equal to the first voltage; the voltage regulating unit includes a digital-to-analog conversion module and a regulating module connected to the digital-to-analog conversion module, and the digital-to-analog conversion module can convert the received voltage value into an analog voltage signal and output it to the regulating module; the regulating module includes a first switch connected in series between the second battery and the output end of the voltage regulating unit, an inductor connected in series with the first switch, a second switch between the inductor and the output end of the voltage regulating unit, a capacitor connected to one end of the second switch, a control circuit for controlling the first switch and the second switch, an error amplifier, and a first resistor and a second resistor connected in series between the output end of the digital-to-analog conversion module and the output end of the voltage regulating unit.

2. The charging compartment circuit according to claim 1, characterized in that: The charging compartment circuit further includes a setting unit and an adder, the setting unit being configured to set the second voltage value, the second voltage value representing the voltage drop of the charging current across the voltage divider resistor connected in series with the first battery in the wireless headset circuit, the adder being capable of receiving the first voltage value of the first battery fed back by the wireless headset circuit to calculate the sum of the first voltage value and the second voltage value as the total voltage value, outputting the sum to the voltage adjustment unit, wherein: The adder is connected to the wireless headset circuit during charging to receive the first voltage value; or The charging compartment circuit also includes a second wireless communication unit connected to the adder, and the second wireless communication unit can communicate with the first wireless communication unit of the wireless headset circuit so that the adder receives the first voltage value fed back by the wireless headset circuit.

3. The charging compartment circuit according to claim 1, characterized in that: The voltage regulating unit is capable of receiving the total voltage value fed back by the wireless headset circuit, wherein: The voltage regulating unit is connected to the wireless headset circuit during charging to receive the total voltage value; or, The charging compartment circuit also includes a second wireless communication unit connected to the voltage regulating unit, and the second wireless communication unit can communicate with the first wireless communication unit of the wireless headset circuit so that the voltage regulating unit receives the total voltage value fed back by the wireless headset circuit.

4. The charging compartment circuit according to claim 2 or 3, characterized in that: The regulating module regulates the first voltage to the second voltage according to the analog voltage signal and outputs the second voltage, and the voltage value received by the digital-to-analog conversion module is equal to the value of the second voltage, wherein: The voltage value received by the digital-to-analog conversion module is the total voltage value; or, The charging compartment circuit also includes a selection unit for receiving the total voltage value. When the first battery is charged with a constant current, the selection unit outputs the total voltage value to the digital-to-analog conversion module; when the first battery is charged with a constant voltage, the selection unit outputs a first reference voltage value to the digital-to-analog conversion module. The first reference voltage value represents the voltage value required by the wireless headset circuit when the first battery is charged with a constant voltage.

5. The charging compartment circuit according to claim 4, characterized in that: The first output terminal of the control circuit is connected to the first switch for controlling the on and off of the first switch, and the second output terminal of the control circuit is connected to the second switch for controlling the on and off of the second switch. The positive input terminal of the error amplifier is connected between the first resistor and the second resistor, the negative input terminal of the error amplifier is connected to the second ground terminal between the inductor and the capacitor, and the output terminal of the error amplifier is connected to the input terminal of the control circuit, wherein: when the first switch is closed, the second switch is opened, and the inductor stores energy; when the first switch is opened, the second switch is closed, and the inductor releases energy, so that the output terminal of the voltage regulation unit outputs the second voltage; and / or, The digital-to-analog conversion module includes an operational amplifier, a third resistor connected between the second voltage terminal and the second ground terminal, and multiple series resistors connected between the second voltage terminal and the third voltage terminal. The third voltage terminal is the output terminal of the digital-to-analog conversion module. A control switch is connected in parallel to each of the series resistors. The digital-to-analog conversion module includes multiple input terminals for receiving voltage values. The multiple input terminals are connected to the multiple control switches in a one-to-one correspondence to control the conduction and closing of the corresponding control switches. The output terminal of the operational amplifier is connected to the third voltage terminal, the positive input terminal of the operational amplifier is connected to the second reference voltage, and the negative input terminal of the operational amplifier is connected to the second voltage terminal.

6. A charging compartment, characterized in that: Comprising a charging compartment circuit according to any one of claims 1-5.

7. A charging system, characterized in that: The charging system includes a charging compartment circuit according to any one of claims 1-5, the charging compartment circuit charges the wireless earphone circuit, the wireless earphone circuit includes a feedback unit, a first battery and a voltage divider resistor connected in series between a first ground terminal and a first voltage terminal, the first voltage terminal and the first ground terminal can be disconnected from the charging compartment circuit, the feedback unit is used to feedback the first voltage value of the first battery or the function value with the first voltage value of the first battery as a variable to the charging compartment circuit, so that the charging compartment circuit can provide a charging voltage according to the sum of the first voltage value and the voltage drop of the set voltage divider resistor during charging; wherein, one of the wireless earphone circuit and the charging compartment circuit includes a setting unit and an adder.

8. A charging method applied to the charging system according to claim 7, characterized in that: The charging method includes: measuring a total voltage value required to charge a first battery of the wireless headset circuit; After adjusting the first voltage output by the second battery of the charging compartment circuit to a second voltage according to the total voltage value, the second voltage is output to the wireless headset circuit to charge the first battery. Furthermore, the value of the second voltage is equal to the value of the total voltage; wherein: the absolute value of the second voltage is greater than or equal to the first voltage; or the absolute value of the second voltage is less than or equal to the first voltage.

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