Charging box switching circuit, charging box and wireless earphone system

Abstract

A charging box switching circuit, a charging box, and a wireless headset system relate to the technical field of wireless headsets and can reduce the number of exposed terminals on wireless headsets to reduce the probability of poor contact due to contamination of the exposed terminals. The charging box switching circuit includes: a charging box communication terminal, a charging box connection terminal, and a charging control signal terminal; a charging box communication circuit, which is connected in series between the charging box communication terminal and the charging box connection terminal, and is used to respond to the communication signal voltage on the charging box communication terminal or the charging box connection terminal to connect the charging box communication terminal and the charging box connection terminal. The charging box communication circuit is also used to respond to the charging voltage on the charging box connection terminal to cut off the connection between the charging box connection terminal and the charging box communication terminal, and the charging voltage is greater than the communication signal voltage; a charging box charging circuit and a charging switching control circuit, and the charging box charging circuit is used to charge the charging box connection terminal based on the charging voltage.

Description

Technical Field

[0001] The present application relates to the technical field of wireless earphones, and in particular to a charging box switching circuit, a charging box, and a wireless earphone system. Background Art

[0002] Current wireless earphones need to be used with a charging box, such as Figure 1 As shown, Figure 1 This is a schematic diagram of the status of a wireless headset and a charging box in the prior art. When the headset 200 is placed in the charging box 100, on the one hand, the charging box 100 needs to charge the headset 200, and on the other hand, the charging box 100 also needs to communicate with the headset 200, such as reading the headset power, controlling the headset Bluetooth pairing connection, etc. Therefore, three external pins 300 need to be set on the charging box 100. These three external pins 300 are respectively a communication terminal, a charging terminal and a ground terminal. In this way, three exposed terminals also need to be set on the wireless headset 200, and the exposed terminals on the headset are easily contaminated and cause poor contact. Summary of the Invention

[0003] Provided are a charging box switching circuit, a charging box, and a wireless earphone system, which can reduce the number of exposed terminals on the wireless earphones and thereby reduce the probability of poor contact due to contamination of the exposed terminals.

[0004] In the first aspect, a charging box switching circuit includes: a charging box communication terminal for electrically connecting to the pins of the charging box microcontroller unit; a charging box connection terminal for electrically connecting to the external pins of the charging box; a charging box communication circuit, the charging box communication circuit is connected in series between the charging box communication terminal and the charging box connection terminal, the charging box communication circuit is used to respond to the communication signal voltage on the charging box communication terminal or the charging box connection terminal to make the charging box communication terminal and the charging box connection terminal conductive, and the charging box communication circuit is also used to respond to the charging voltage on the charging box connection terminal to cut off the charging box connection terminal and the charging box communication terminal, and the charging voltage is greater than the communication signal voltage; the charging box A control signal terminal, used to electrically connect the pins of the charging box microcontroller unit; a charging box charging circuit, the charging box charging circuit is electrically connected to the charging box connection terminal, and the charging box charging circuit is used to charge the charging box connection terminal based on the charging voltage; a charging switching control circuit, the charging switching control circuit is electrically connected to the charging control signal terminal and the charging box charging circuit, and the charging switching control circuit is used to control the charging box charging circuit to charge the charging box connection terminal in response to the charging signal of the charging control signal terminal, and the charging switching control circuit is also used to control the charging box charging circuit to stop charging the charging box connection terminal in response to the charging stop signal of the charging control signal terminal.

[0005] The charging box switching circuit can realize the on-off control between the charging box communication terminal and the charging box connection terminal through the charging box communication circuit, and can realize the control of charging or stopping charging to the charging box connection terminal through the charging box charging circuit and the charging switching control circuit, that is, it is realized that the same terminal has both charging and communication functions. Even wireless headphones can realize both charging and communication functions between the same terminal and the charging box, which can reduce the number of exposed terminals of wireless headphones, thereby reducing the probability of poor contact due to contamination of the exposed terminals.

[0006] In one possible embodiment, a discharge circuit is electrically connected to the charging box connection terminal and the charging switching control circuit. The discharge circuit is configured to control the charging box connection terminal to discharge to the communication signal voltage when the charging switching control circuit controls the charging circuit of the charging box to stop charging the charging box connection terminal. After charging is completed, the charging box connection terminal is first quickly discharged through the discharge circuit to avoid the adverse effects of the charging voltage on communication during subsequent communication.

[0007] In one possible embodiment, the charging box communication circuit includes: a first voltage terminal, the first voltage terminal is used to provide a first voltage; a first transistor, the first transistor is an N-type metal oxide semiconductor field effect transistor (MOSFET), the source of the first transistor is electrically connected to the charging box communication terminal, and the drain of the first transistor is electrically connected to the charging box connection terminal; a first resistor, the gate of the first transistor is electrically connected to the first voltage terminal through the first resistor; and a second resistor, the second resistor is connected in series between the gate and source of the first transistor. The first transistor made of N-type MOSFET can automatically control the first transistor itself according to the voltage level on the charging box connection terminal P1 to avoid mutual influence between the communication voltage and the charging voltage.

[0008] In one possible embodiment, the charging box switching circuit also includes: a second voltage terminal, the second voltage terminal is used to provide a charging voltage, the charging voltage is higher than the first voltage; the charging box charging circuit includes a second transistor, the second transistor is a P-type MOSFET, the source of the second transistor is electrically connected to the second voltage terminal, the drain of the second transistor is electrically connected to the charging box connection terminal, and the gate of the second transistor is electrically connected to the control node; the charging switching control circuit includes: a third transistor, the third transistor is an N-type MOSFET, the source of the third transistor is grounded, and the drain of the third transistor is electrically connected to the control node; a third resistor, the third resistor is connected in series between the charging control signal terminal and the gate of the third transistor; a fourth resistor, the fourth resistor is connected in series between the source and gate of the third transistor; a fifth resistor, the fifth resistor is connected in series between the second voltage terminal and the control node; a capacitor, the capacitor is connected in series between the second voltage terminal and the control node.

[0009] In one possible embodiment, the charging box switching circuit also includes a discharge circuit, which includes: a third voltage terminal, the third voltage terminal is used to provide a second voltage, the second voltage is a higher voltage among the communication voltages, and the second voltage is lower than the first voltage; a fourth transistor, the fourth transistor is an N-type MOSFET, the drain of the fourth transistor is electrically connected to the charging box connection terminal, and the gate of the fourth transistor is electrically connected to the control node; and a fifth transistor, the fifth transistor is a P-type MOSFET, the source of the fifth transistor is electrically connected to the source of the fourth transistor, the drain of the fifth transistor is grounded, and the gate of the fifth transistor is electrically connected to the third voltage terminal. By setting the fourth and fifth transistors, the charging box connection terminal can be automatically discharged just after charging is completed, and it is ensured that the communication signal will not be affected during the communication process.

[0010] In a possible implementation, the discharge circuit further includes: a sixth resistor connected in series between the third voltage terminal and the gate of the fifth transistor; and a seventh resistor connected in series between the gate and the drain of the fifth transistor.

[0011] In one possible embodiment, the charging box micro control unit includes a communication pin and a control pin; the charging box communication terminal is used to electrically connect the communication pin of the charging box micro control unit, and the charging control signal terminal is used to electrically connect the control pin of the charging box micro control unit.

[0012] In a second aspect, a charging box includes a charging box switching circuit in any possible implementation of the first aspect.

[0013] In a third aspect, a wireless headset system includes a charging box and a wireless headset, wherein the charging box includes the charging box switching circuit in any possible implementation of the first aspect.

[0014] In one possible embodiment, a wireless headset includes a wireless headset switching circuit, which includes: a headset terminal for electrically connecting to an external pin of the headset; a headset communication terminal for electrically connecting to a headset microcontroller unit; a headset communication circuit connected in series between the headset terminal and the headset communication terminal, the headset communication circuit for transmitting a communication signal to the headset communication terminal in response to a communication signal from the headset terminal, the headset communication circuit further for transmitting a communication signal to the headset terminal in response to a communication signal from the headset communication terminal, and the headset communication circuit further for shutting off the connection between the headset terminal and the headset communication terminal in response to a charging voltage on the headset terminal; a headset power terminal for providing power to a battery in the wireless headset; and a headset charging circuit connected in series between the headset terminal and the headset power terminal, the headset charging circuit for conducting the connection between the headset terminal and the headset power terminal in response to a charging voltage on the headset terminal, and the headset charging circuit further for shutting off the connection between the headset terminal and the headset power terminal in response to a communication signal voltage on the headset terminal. The wireless headset communication circuit and the headset charging circuit can automatically switch between communication and charging functions based on the voltage on the headset terminal.

[0015] In one possible embodiment, the earphone communication circuit includes: a fourth voltage terminal, the fourth voltage terminal is used to provide a second voltage; a sixth transistor, the sixth transistor is an N-type MOSFET, the drain of the sixth transistor is electrically connected to the earphone terminal, the source of the sixth transistor is electrically connected to the earphone communication terminal, and the gate of the sixth transistor is electrically connected to the fourth voltage terminal; an eighth resistor, the eighth resistor is connected in series between the fourth voltage terminal and the source of the sixth transistor; the earphone charging circuit includes: a fifth voltage terminal, the fifth voltage terminal is used to provide a first voltage; a seventh transistor, the seventh transistor is a P-type MOSFET, the source of the seventh transistor is electrically connected to the earphone terminal, the drain of the seventh transistor is electrically connected to the earphone power supply terminal, and the gate of the seventh transistor is electrically connected to the fifth voltage terminal.

[0016] In a possible implementation, the earphone communication circuit further includes a ninth resistor, and the gate of the sixth transistor is electrically connected to the fourth voltage terminal through the ninth resistor.

[0017] In a possible implementation, the earphone charging circuit further includes a tenth resistor, and the seventh transistor is electrically connected to the fifth voltage terminal through the tenth resistor.

[0018] In a possible implementation, the wireless headset switching circuit may further include an electrostatic discharge circuit, and the headset terminal is grounded through the electrostatic discharge circuit.

[0019] The charging box switching circuit, charging box and wireless earphone system can realize the on-off control between the charging box communication end and the charging box connection end through the charging box communication circuit, and can realize the control of charging or stopping charging to the charging box connection end through the charging box charging circuit and the charging switching control circuit, that is, it is realized that the same terminal has both charging and communication functions. Even wireless earphones can realize both charging and communication functions between the same terminal and the charging box, thereby reducing the number of exposed terminals of the wireless earphones, thereby reducing the probability of poor contact due to contamination of the exposed terminals. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the state of a wireless headset and a charging box in the prior art;

[0021] Figure 2 for Figure 1 The structural block diagram of the corresponding wireless headset and charging box;

[0022] Figure 3 This is a structural block diagram of a charging box switching circuit in an embodiment of the present application;

[0023] Figure 4 This is a structural block diagram of a wireless headset switching circuit in an embodiment of the present application;

[0024] Figure 5 This is a circuit diagram of a charging box switching circuit in an embodiment of the present application;

[0025] Figure 6 This is a circuit diagram of a wireless headset switching circuit in an embodiment of the present application. DETAILED DESCRIPTION

[0026] 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.

[0027] Before introducing the embodiments of the present application, the process of proposing the embodiments of the present application is first described. Figure 1 and Figure 2 As shown, Figure 2 for Figure 1The corresponding structural block diagram of the wireless headset and the charging box when they are matched, the wireless headset 200 and the charging box 100 are grounded through the ground terminal, the wireless headset 200 and the charging box 100 realize the electrical connection between the headset charging circuit and the charging box charging circuit through the charging terminal to realize the charging function, and the wireless headset 200 and the charging box 100 realize the communication connection between the headset microcontroller unit (MCU) and the charging box MCU through the communication terminal to realize the communication function between the headset 200 and the charging box 100. Since three exposed terminals need to be set on the wireless headset 200, the number of exposed terminals is large, which is easy to be contaminated and cause poor contact. Therefore, the inventor proposed the technical solution in the embodiment of the present application, and the technical solution in the embodiment of the present application is described below.

[0028] like Figure 3 As shown, Figure 3This is a structural block diagram of a charging box switching circuit in an embodiment of the present application. The embodiment of the present application provides a charging box switching circuit, including: a charging box communication terminal S1, which is used to electrically connect to the pins of the charging box microcontroller unit MCU; a charging box connection terminal P1, which is used to electrically connect to the external pins of the charging box; a charging box communication circuit 11, and the charging box communication circuit 11 is connected in series between the charging box communication terminal S1 and the charging box connection terminal P1. The charging box communication terminal S1 is a communication interface between the charging box MCU and the charging box communication circuit 11. For example, the charging box communication terminal S1 is electrically connected to the communication pin on the charging box MCU. The communication signal generated by the charging box MCU can be transmitted to the charging box communication circuit 11 through the charging box communication terminal S1 so as to be further transmitted to the wireless headset. The charging box MCU can also receive the communication signal from the wireless headset through the charging box communication terminal S1 so as to control the charging box accordingly according to the signal; the charging box connection terminal P1 is used to electrically connect the external pins of the charging box, and the external pins of the charging box are used to contact the external pins of the wireless headset so as to connect the charging box and the wireless headset. The charging box can send signals to the wireless headset through the charging box connection terminal P1 and receive signals from the wireless headset through the charging box connection terminal P1; the charging box communication circuit 11 is used to respond to the communication signal on the charging box communication terminal S1 or the charging box connection terminal P1 of the charging box. The voltage causes conduction between the charging box communication terminal S1 and the charging box connection terminal P1. The charging box communication circuit 11 is also used to respond to the charging voltage on the charging box connection terminal P1 to cut off the connection between the charging box connection terminal P1 and the charging box communication terminal S1. The charging voltage is greater than the communication signal voltage. For example, the communication signal voltage is 0V and 1.8V, that is, the communication signal can be a pulse signal, the high voltage in the pulse signal is 1.8V, the low voltage in the pulse signal is 0V, and the charging voltage is 5V. Among them, the charging box communication terminal S1 is used to transmit communication signals, and the charging box connection terminal P1 is used to connect wireless headphones. When the charging box communication terminal S1 and the charging box connection terminal P1 are conductive, two-way communication between the charging box and the wireless headphones can be achieved. On the one hand, the communication signal generated by the charging box MCU can be transmitted to the wireless headphones through the charging box connection terminal P1. On the other hand, the communication signal generated by the wireless headphones can be transmitted to the charging box MCU through the charging box connection terminal P1.The charging box switching circuit also includes: a charging control signal terminal CTL, which is used to electrically connect to the pin of the charging box microcontroller unit MCU; a charging box charging circuit 12, which is used to charge the charging box connection terminal P1 based on the charging voltage; a charging switching control circuit 13, which is electrically connected to the charging control signal terminal CTL and the charging box charging circuit 12. The charging switching control circuit 13 is used to control the charging box charging circuit 12 to charge the charging box connection terminal P1 in response to the charging signal of the charging control signal terminal CTL. The charging switching control circuit 13 is also used to control the charging box charging circuit 12 to stop charging the charging box connection terminal P2 in response to the charging stop signal of the charging control signal terminal CTL. The charging control signal terminal CTL is a control interface between the charging box MCU and the charging switching control circuit 13. For example, the charging control signal terminal CTL is electrically connected to the control pin on the charging box MCU. The charging box MCU can generate a control signal and provide it to the charging switching control circuit 13 through the charging control signal terminal CTL. The control signal includes the above-mentioned charging signal and the charging stop signal.

[0029] In one possible embodiment, the charging box micro control unit MCU includes a communication pin and a control pin; the charging box communication terminal S1 is used to electrically connect the communication pin of the charging box micro control unit MCU, and the charging control signal terminal CTL is used to electrically connect the control pin of the charging box micro control unit MCU.

[0030] like Figure 4 As shown, Figure 4This is a structural block diagram of a wireless headset switching circuit in an embodiment of the present application. The wireless headset switching circuit is arranged in a wireless headset. The wireless headset switching circuit includes: a headset terminal P2, the headset terminal P2 is used to electrically connect the external pin of the headset, and the external pin of the headset is used to contact the external pin of the charging box, even if the headset terminal P2 is electrically connected to the charging box connection terminal P1, so that the charging box and the wireless headset are connected, the wireless headset can send signals to the charging box through the headset terminal P2 and receive signals from the charging box through the headset terminal P2; a headset communication circuit 21, the headset communication circuit 21 is connected in series between the headset terminal P2 and the headset communication terminal S2, the headset communication circuit 21 is used to respond to the communication signal of the headset terminal P2 and transmit the communication signal to the headset communication terminal S2, the headset communication circuit 21 is also used to respond to the communication signal of the headset communication terminal S2 and transmit the communication signal to the headset terminal P2, the headset communication circuit 21 is also used to respond to the charging voltage on the headset terminal P2 to cut off the connection between the headset terminal P2 and the headset communication terminal S2; a headset charging circuit 22, the headset charging circuit 22 is connected in series with the headset terminal P2 The headphone power terminal VBUS is used to provide power to the battery of the wireless headset to facilitate charging of the battery of the wireless headset. For example, the headphone power terminal VBUS can be a power signal line, which can be electrically connected to the positive terminal of the battery in the wireless headset to facilitate charging of the battery based on the voltage provided by the headphone power terminal VBUS. The power signal line can also be electrically connected to a charging control circuit in the wireless headset to facilitate voltage conversion of the voltage provided by the headphone power terminal VBUS and provide the voltage to the battery for charging. The headphone charging circuit 22 is used to respond to the charging voltage on the headphone terminal P2 to connect the headphone terminal P2 and the headphone power terminal VBUS. The headphone charging circuit 22 is also used to respond to the communication signal voltage on the headphone terminal P2 to disconnect the headphone terminal P2 and the headphone power terminal VBUS. When the wireless headset is placed in the charging box, the headphone external pin on the wireless headset contacts the charging box external pin in the charging box, so that the headphone terminal P2 on the wireless headset is electrically connected to the charging box connection terminal P1 on the charging box.

[0031] Specifically, for example, a Hall sensor can be provided in the charging box, and the charging box determines whether the wireless headset is placed in the charging box based on the Hall sensor. When it is determined that the wireless headset is placed in the charging box, the charging box MCU can generate a power acquisition instruction and transmit the power acquisition instruction signal through the charging box communication terminal S1. At this time, the charging box communication circuit 11 controls the conduction between the charging box communication terminal S1 and the charging box connection terminal P1, so that the power acquisition instruction signal can be transmitted to the wireless headset through the charging box connection terminal P1, and the wireless headset obtains the power acquisition instruction signal through the headset terminal P2. The communication signal on the headset terminal P2 is a pulse signal including low voltage and high voltage. When the communication signal is low voltage, the headset communication circuit 21 conducts between the headset terminal P2 and the headset communication terminal S2, that is, the low voltage of the communication signal can be transmitted to the headset communication terminal S2 to realize the transmission of the communication signal, even if the headset MCU obtains the power acquisition instruction signal through the headset communication terminal S2, and transmits the current power to the headset communication terminal S2 in the form of a signal according to the power acquisition instruction signal, the communication signal of the headset communication terminal S2 is a pulse signal including low voltage and high voltage. Pulse signal, when the communication signal is low voltage, the earphone communication circuit 21 makes the earphone terminal P2 and the earphone communication terminal S2 conductive, that is, the low voltage of the communication signal can be transmitted to the earphone terminal P2, so that the signal corresponding to the current power can be transmitted to the charging box, and the charging box MCU determines whether charging is needed according to the current power of the wireless headset. If charging is needed, the charging box MCU generates a charging signal and transmits it to the charging switching control circuit 3 through the charging control signal terminal CTL. The charging switching control circuit 3 responds to the charging signal to control the charging box charging circuit 12 to charge the charging box connection terminal P1. The charging voltage is 5V, that is, a 5V charging voltage is charged to the charging box connection terminal P1 to enable the charging box to charge the wireless headset. At this time, there is a 5V charging voltage on the earphone terminal P2, and the earphone communication circuit 21 is cut off in response to the charging voltage on the earphone terminal P2. The earphone charging circuit 22 responds to the charging voltage on the earphone terminal P2 to make the earphone terminal P2 and the earphone power supply terminal VBUS conductive, so as to realize the charging of the earphone power supply terminal VBUS with a 5V charging voltage through the earphone charging circuit 22, that is, the charging of the wireless headset through the charging box is realized. After charging is completed, the charging box MCU generates a charging stop signal and transmits it to the charging switching control circuit 3 through the charging control signal terminal CTL. In response to the charging stop signal, the charging switching control circuit 3 controls the charging box charging circuit 12 to stop charging the charging box connection terminal P1.

[0032] It should also be noted that the charging box in the embodiment of the present application may also include a grounding terminal. Similarly, the wireless headset may also include a grounding terminal. When the wireless headset is placed in the charging box, the external pin of the charging box contacts the external pin of the headset. Even if the charging box connection end P1 is electrically connected to the headset terminal P2, the electrical connection between the two can realize the communication and charging functions between the charging box and the wireless headset. At the same time, the grounding terminal of the charging box can contact the grounding terminal of the wireless headset to realize the grounding function, that is, the number of exposed terminals of the wireless headset can be reduced while achieving the same function.

[0033] The charging box switching circuit in the embodiment of the present application can realize the on-off control between the charging box communication end and the charging box connection end through the charging box communication circuit, and can realize the control of charging or stopping charging to the charging box connection end through the charging box charging circuit and the charging switching control circuit, that is, it is realized that the same terminal has both charging and communication functions. Even wireless headphones can realize both charging and communication functions between the same terminal and the charging box, which can reduce the number of exposed terminals of wireless headphones, thereby reducing the probability of poor contact due to contamination of the exposed terminals.

[0034] In one possible implementation, Figure 3 As shown, the charging box switching circuit may further include a discharge circuit 14, which is electrically connected to the charging box connection terminal P1 and the charging switching control circuit 13. The discharge circuit 14 is used to control the discharge of the charging box connection terminal P1 to the communication signal voltage when the charging switching control circuit 13 controls the charging box charging circuit 12 to stop charging the charging box connection terminal P1. Since the voltage value of the charging voltage is high and the voltage value of the communication signal is low, after charging is completed, the charging box connection terminal P1 is first quickly discharged through the discharge circuit 14, which can avoid the influence of the charging voltage on the communication during subsequent communication.

[0035] In one possible implementation, Figure 5 As shown, Figure 5This is a circuit diagram of a charging box switching circuit in an embodiment of the present application, and the charging box communication circuit 11 includes: a first voltage terminal VDD1, the first voltage terminal VDD1 is used to provide a first voltage, and the first voltage is, for example, 3.3V; a first transistor Q1, the first transistor Q1 is an N-type metal oxide semiconductor field-effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET), the source S of the first transistor Q1 is electrically connected to the charging box communication terminal S1, and the drain D of the first transistor Q1 is electrically connected to the charging box connection terminal P1; a first resistor R1, the gate G of the first transistor Q1 is electrically connected to the first voltage terminal VDD1 through the first resistor R1; a second resistor R2, the second resistor R2 is connected in series between the gate G and the source S of the first transistor Q1.

[0036] Specifically, the charging box communication terminal S1 is an interface for the charging box MCU to transmit and receive communication signals. The communication signal is, for example, a pulse signal formed by 0V and 1.8V. When the charging box communication terminal S1 provides a communication signal for transmission, the gate G voltage of the first transistor Q1 is higher than the source S voltage, so that the first transistor Q1 is turned on, that is, the source S and the drain D of the first transistor Q1 are turned on, and the communication signal can be transmitted to the charging box connection terminal P1 through the first transistor Q1 to realize communication between the charging box and the wireless headset; when the charging box communication terminal S1 does not provide a communication signal for transmission, the source S of the first transistor Q1 is pulled up due to the pull-up effect of the first resistor R1 and the second resistor R2, and the source S voltage of the first transistor Q1 is pulled up, and the voltage difference between its gate G and source S is very small. At this time, the first transistor Q1 is controlled to be cut off; when there is a communication signal from the wireless headset at the charging box connection terminal P1, the first transistor Q1 is turned off. The source S voltage of the body transistor Q1 is close to 3.3V, and the communication signal voltages of 0V and 1.8V are lower than 3.3V. At this time, since the direction of the parasitic diode of the first transistor Q1 is from the source S to the drain D, the effect of the parasitic diode will cause the source S voltage of the first transistor Q1 to be pulled down. When the source S voltage of the first transistor Q1 is pulled down to make the gate-source voltage difference reach the threshold voltage, the first transistor Q1 will be controlled to be turned on, even if the communication signal on the charging box connection terminal P1 is transmitted to the charging box communication terminal S1 through the first transistor Q1; when the charging box charges the wireless headset through the charging box connection terminal P1, the voltage on the charging box connection terminal P1 is the charging voltage, for example 5V. At this time, the charging box communication terminal S1 will not generate a signal, and the source S of the first transistor Q1 will be pulled up due to the pull-up effect of the first resistor R1 and the second resistor R2, thereby controlling the first transistor Q1 to be cut off, that is, ensuring that charging will not have an adverse effect on the communication path.

[0037] In one possible implementation, Figure 5As shown, the charging box switching circuit also includes a second voltage terminal VDD2, which is used to provide a charging voltage. The charging voltage is higher than the first voltage, and the charging voltage is, for example, 5V; the charging box charging circuit 12 includes a second transistor Q2, and the second transistor Q2 is a P-type MOSFET. The source S of the second transistor Q2 is electrically connected to the second voltage terminal VDD2, the drain D of the second transistor Q2 is electrically connected to the charging box connection terminal P1, and the gate G of the second transistor Q2 is electrically connected to the control node O. The charging box charging circuit 12 may include at least one second transistor Q2, for example, Figure 5 In the structure shown, there are two second transistors Q2, and the two second transistors Q2 have the same structure; the charging switching control circuit 13 includes a third transistor Q3, which is an N-type MOSFET, with a source S of the third transistor Q3 grounded and a drain D of the third transistor Q3 electrically connected to the control node O; a third resistor R3, which is connected in series between the charging control signal terminal CTL and the gate G of the third transistor Q3; a fourth resistor R4, which is connected in series between the source S and the gate G of the third transistor Q3; a fifth resistor R5, which is connected in series between the second voltage terminal VDD2 and the control node O; and a capacitor C, which is connected in series between the second voltage terminal VDD2 and the control node O.

[0038] Specifically, when the wireless headset needs to be charged through the charging box, the charging box MCU provides a high level through the charging control signal terminal CTL, and the third transistor Q3 is turned on in response to the high level of the charging control signal terminal CTL. Even if the control node O is grounded through the third transistor Q3, the control node O is a low voltage of 0V, even if the gate G potential of the second transistor Q2 is 0V, since the gate G potential of the second transistor Q2 is 0V lower than the source S potential of 5V, the second transistor Q2 is controlled to be turned on, so that the second voltage terminal VDD2 is turned on through the second transistor Q2 and the charging box connection terminal P1, and the 5V charging level of the second voltage terminal VDD2 is charged into the charging box connection terminal P1 through the second transistor Q2, which realizes charging of the wireless headset through the charging box connection terminal P1. When there are two second transistors Q2, the second voltage terminal VDD2 can charge the charging box connection terminal P1 through the path provided by the two second transistors Q2, thereby increasing the charging current. After charging is completed, the charging box MCU provides a low voltage through the charging control signal terminal CTL or the charging box MCU no longer provides a signal to the charging control signal terminal CTL. The low voltage provided by the charging box MCU to the charging control signal terminal CTL will pull down the gate G of the third transistor Q3. If the charging box MCU no longer provides a signal to the charging control signal terminal CTL, the gate G voltage of the third transistor Q3 will be pulled down due to the fourth resistor R4. The third transistor Q3 is cut off in response to the low voltage of the gate G, and the 5V charging level of the second voltage terminal VDD2 pulls up the voltage of the control node O through the fifth resistor R5. When the voltage of the control node O is pulled high, the second transistor Q2 is cut off in response to the high voltage of the control node O, even if the 5V charging level of the second voltage terminal VDD2 cannot continue to charge the charging box connection terminal P1 through the second transistor Q2.

[0039] In one possible implementation, Figure 5 As shown, the discharge circuit 14 includes: a third voltage terminal VDD3, the third voltage terminal VDD3 is used to provide a second voltage, the second voltage is a high voltage in the communication voltage, for example, 1.8V, and the second voltage is lower than the first voltage; a fourth transistor Q4, the fourth transistor Q4 is an N-type MOSFET, the drain D of the fourth transistor Q4 is electrically connected to the charging box connection terminal P1, and the gate G of the fourth transistor Q4 is electrically connected to the control node O; the fifth transistor Q5, the fifth transistor Q5 is a P-type MOSFET, the source S of the fifth transistor Q5 is electrically connected to the source S of the fourth transistor Q4, the drain D of the fifth transistor Q5 is grounded, and the gate G of the fifth transistor Q5 is electrically connected to the third voltage terminal VDD3.

[0040] Specifically, when charging has just ended, the control node O is at a high voltage, and the charging box connection terminal P1 is at a 5V charging voltage, the fourth transistor Q4 is turned on because its gate G is at a high level, and the fifth transistor Q5 is turned on because its gate G voltage is 1.8V lower than its source S voltage. Even if the charging box connection terminal P1 is grounded through the fourth transistor Q4 and the fifth transistor Q5, the 5V charging voltage on the charging box connection terminal P1 is quickly discharged. When discharged to 1.8V, the fifth transistor Q5 is turned off. By discharging the charging box connection terminal P1 after charging is completed, the adverse effects of the charging voltage at the charging box connection terminal P1 on the communication process can be avoided. During the charging process, since the control node O is at a low voltage, the fourth transistor Q4 can be controlled to be turned off to prevent the charging box connection terminal P1 from being discharged by the discharge circuit 14 during the charging process. During the communication process, since the voltage of the communication signal is 0V and 1.8V, that is, the voltage on the charging box connection terminal P1 is 0V or 1.8V, and the gate G voltage of the fifth transistor Q5 is 1.8V, it can be ensured that the fifth transistor Q5 is in the cut-off state during the communication process and will not affect the communication signal.

[0041] In one possible implementation, Figure 5 As shown, the discharge circuit 14 further includes a sixth resistor R6 connected in series between the third voltage terminal VDD3 and the gate G of the fifth transistor Q5; and a seventh resistor R7 connected in series between the gate G and the drain D of the fifth transistor Q5.

[0042] In one possible implementation, Figure 6 As shown, Figure 6 This is a circuit diagram of a wireless headset switching circuit according to an embodiment of the present application. The headset communication circuit 21 includes: a fourth voltage terminal VDD4, which is used to provide a second voltage, which is a high voltage of a communication signal, for example, 1.8V; a sixth transistor Q6, which is an N-type MOSFET, having a drain D electrically connected to the headset terminal P2, a source S electrically connected to the headset communication terminal S2, and a gate G electrically connected to the fourth voltage terminal VDD4; and an eighth resistor R8, which is connected in series between the fourth voltage terminal VDD4 and the source S of the sixth transistor Q6. Optionally, the headset communication circuit 21 also includes a ninth resistor R9, through which the gate G of the sixth transistor Q6 is electrically connected to the fourth voltage terminal VDD4.

[0043] Specifically, during charging, the headphone terminal P2 has a charging voltage of 5V, the headphone MCU does not provide a communication signal to the headphone terminal P2, and the source S of the sixth transistor Q6 is pulled to 1.8V through the eighth resistor R8. Since the voltage between the gate G and the source S of the sixth transistor Q6 is 1.8V, the sixth transistor Q6 is cut off, and the charging voltage on the headphone terminal P2 does not affect the headphone communication terminal S2. In the non-charging state, when a communication signal is sent from the charging box to the wireless headset, there is a communication signal on the headset terminal P2, and the communication signal is a pulse signal composed of 0V and 1.8V. When the voltage on the headset terminal P2 is 0V, since the direction of the parasitic diode on the sixth transistor Q6 is from the source S to the drain D, the parasitic diode on the sixth transistor Q6 will pull down the voltage of its source S, thereby turning on the sixth transistor Q6, so that the 0V voltage at the headset terminal P2 is transmitted to the headset communication terminal S2 through the sixth transistor Q6. When the voltage on the headset terminal P2 is 1.8V, due to the action of the eighth resistor R8, the voltage of the headset communication terminal S2 is pulled up to 1.8V. That is to say, when the headset terminal P2 has a communication signal, the communication signal will be transmitted to the headset communication terminal S2 through the headset communication circuit 21.

[0044] In one possible implementation, Figure 6 As shown, the headphone charging circuit 22 includes: a fifth voltage terminal VDD5, which is used to provide a first voltage, for example, 3.3V; a seventh transistor Q7, which is a P-type MOSFET, with a source S electrically connected to the headphone terminal P2, a drain D electrically connected to the headphone power supply terminal VBUS, and a gate G electrically connected to the fifth voltage terminal VDD5. The headphone charging circuit 22 may, for example, include two seventh transistors Q7, each having the same connection structure to provide a higher charging current. Optionally, the headphone charging circuit 22 also includes a tenth resistor R10, through which the seventh transistor Q7 is electrically connected to the fifth voltage terminal VDD5. The wireless headphone switching circuit may also include an electrostatic discharge (ESD) circuit E, with the headphone terminal P2 grounded via the ESD circuit E.

[0045] Specifically, during charging, the headphone terminal P2 has a 5V charging voltage, and the seventh transistor Q7 is turned on because the gate G voltage is lower than the source S voltage and exceeds the threshold. The headphone terminal P2 can be charged to the headphone power supply terminal VBUS through the seventh transistor Q7; in the non-charging state, during communication, there is a communication signal on the headphone terminal P2, such as 0V or 1.8V voltage. At this time, the gate G voltage of the seventh transistor Q7 is higher than the source S voltage, so the seventh transistor Q7 is turned off, so that during communication, the headphone power supply terminal VBUS will not have an adverse effect on the communication signal.

[0046] An embodiment of the present application provides a charging box, comprising: a charging box microcontroller unit MCU, a charging box external pin, and the charging box switching circuit in the above embodiment, the charging box microcontroller unit MCU comprises a communication pin and a control pin, the communication pin of the charging box microcontroller unit MCU is electrically connected to the charging box communication terminal S1 in the charging box switching circuit, the control pin of the charging box control unit MCU is electrically connected to the charging control signal terminal CTL in the charging box switching circuit, and the charging box external pin is electrically connected to the charging box connection terminal P1 in the charging box switching circuit. The charging box microcontroller unit MCU is used to generate a control signal and provide it to the charging switching control circuit 13 through the charging control signal terminal CTL to achieve control of the charging switching control circuit 13, the control signal includes the above-mentioned charging signal and the charging stop signal, the charging box microcontroller unit MCU is also used to generate a communication signal and send the communication signal to the wireless headset through the charging box communication circuit 11 and the charging box external pin, and receive the communication signal from the wireless headset through the charging box communication circuit 11 and the charging box external pin.

[0047] The charging box in the embodiment of the present application can realize the on-off control between the charging box communication end and the charging box connection end through the charging box communication circuit, and can realize the control of charging or stopping charging to the charging box connection end through the charging box charging circuit and the charging switching control circuit, that is, it is realized that the same terminal has both charging and communication functions. Even wireless headphones can realize both charging and communication functions between the same terminal and the charging box, thereby reducing the number of exposed terminals of wireless headphones, thereby reducing the probability of poor contact due to contamination of the exposed terminals.

[0048] An embodiment of the present application also provides a wireless headset system, including a charging box and wireless headsets, the charging box including the charging box switching circuit in the above embodiment, the wireless headset including a headset microcontroller unit MCU, a charging control circuit, a headset external pin and the wireless headset switching circuit in the above embodiment, the headset microcontroller unit MCU is electrically connected to the headset communication terminal S2 in the wireless headset switching circuit, the headset microcontroller unit MCU is used to control the wireless headset, the headset microcontroller unit MCU is also used to generate a communication signal, and send the communication signal to the charging box through the headset communication circuit 21 and the headset external pin, the headset microcontroller unit MCU is also used to receive the communication signal from the charging box through the headset external pin and the headset communication circuit 21. The headset external pin is electrically connected to the headset connection terminal P2 in the wireless headset switching circuit. The charging control circuit is electrically connected to the headset power supply terminal VBUS in the wireless headset switching circuit, and the charging control circuit is used to charge the battery in the wireless headset based on the voltage provided by the headset power supply terminal VBUS.

[0049] The wireless earphone system in the embodiment of the present application can realize the on-off control between the charging box communication terminal and the charging box connection terminal through the charging box communication circuit, and can realize the control of charging or stopping charging to the charging box connection terminal through the charging box charging circuit and the charging switching control circuit, that is, it is realized that the same terminal has both charging and communication functions. Even the wireless earphones can realize both charging and communication functions between the same terminal and the charging box, thereby reducing the number of exposed terminals of the wireless earphones, thereby reducing the probability of poor contact due to contamination of the exposed terminals.

[0050] In the embodiments of the present application, "at least one" refers to one or more, and "more" 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 next 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.

[0051] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A charging box switching circuit, characterized in that: include: Charging box communication terminal, used to electrically connect to the pin of the charging box micro control unit; Charging box connection terminal, used for electrically connecting to the external pins of the charging box; A charging box communication circuit, the charging box communication circuit is connected in series between the charging box communication terminal and the charging box connection terminal, the charging box communication circuit is used to respond to the communication signal voltage on the charging box communication terminal or the charging box connection terminal to make the charging box communication terminal and the charging box connection terminal conductive, and the charging box communication circuit is also used to respond to the charging voltage on the charging box connection terminal to cut off the charging box connection terminal and the charging box communication terminal, and the charging voltage is greater than the communication signal voltage; Charging control signal terminal, used to electrically connect to the pin of the charging box micro control unit; A charging circuit for the charging box, the charging circuit for the charging box being electrically connected to the connection end of the charging box, and the charging circuit for the charging box being used to charge the connection end of the charging box based on a charging voltage; A charging switching control circuit, the charging switching control circuit being electrically connected to the charging control signal terminal and the charging box charging circuit, the charging switching control circuit being used to control the charging box charging circuit to charge the charging box connection terminal in response to a charging signal from the charging control signal terminal, and the charging switching control circuit being further used to control the charging box charging circuit to stop charging the charging box connection terminal in response to a charging stop signal from the charging control signal terminal; a second voltage terminal, the second voltage terminal being used to provide a charging voltage; The charging box charging circuit includes a second transistor, which is a P-type MOSFET, a source of the second transistor is electrically connected to the second voltage terminal, a drain of the second transistor is electrically connected to the charging box connection terminal, and a gate of the second transistor is electrically connected to the control node; The charging switching control circuit includes: a third transistor, the third transistor being an N-type MOSFET, a source of the third transistor being grounded, and a drain of the third transistor being electrically connected to the control node; a third resistor, the third resistor being connected in series between the charging control signal terminal and the gate of the third transistor; a fourth resistor, the fourth resistor being connected in series between the source and the gate of the third transistor; a fifth resistor, connected in series between the second voltage terminal and the control node; A capacitor is connected in series between the second voltage terminal and the control node.

2. The charging box switching circuit according to claim 1, characterized in that: Also includes: A discharge circuit is electrically connected to the charging box connection end and the charging switching control circuit. The discharge circuit is used to control the discharge of the charging box connection end to the communication signal voltage when the charging switching control circuit controls the charging box charging circuit to stop charging the charging box connection end.

3. The charging box switching circuit according to claim 1, characterized in that: The charging box communication circuit includes: a first voltage terminal, the first voltage terminal being used to provide a first voltage; a first transistor, wherein the first transistor is an N-type metal oxide semiconductor field effect transistor (MOSFET), a source of the first transistor is electrically connected to the charging box communication terminal, and a drain of the first transistor is electrically connected to the charging box connection terminal; a first resistor, wherein the gate of the first transistor is electrically connected to the first voltage terminal through the first resistor; A second resistor is connected in series between the gate and the source of the first transistor.

4. The charging box switching circuit according to claim 3, characterized in that: The charging voltage is higher than the first voltage.

5. The charging box switching circuit according to claim 4, characterized in that: Also included is a discharge circuit, the discharge circuit comprising: a third voltage terminal, the third voltage terminal being used to provide a second voltage, the second voltage being a higher voltage among the communication signal voltages, and the second voltage being lower than the first voltage; a fourth transistor, the fourth transistor being an N-type MOSFET, the drain of the fourth transistor being electrically connected to the charging box connection end, and the gate of the fourth transistor being electrically connected to the control node; A fifth transistor, wherein the fifth transistor is a P-type MOSFET, a source of the fifth transistor is electrically connected to the source of the fourth transistor, a drain of the fifth transistor is grounded, and a gate of the fifth transistor is electrically connected to the third voltage terminal.

6. The charging box switching circuit according to claim 5, characterized in that: The discharge circuit further includes: a sixth resistor, the sixth resistor being connected in series between the third voltage terminal and the gate of the fifth transistor; A seventh resistor is connected in series between the gate and the drain of the fifth transistor.

7. The charging box switching circuit according to claim 1, characterized in that: The charging box micro control unit includes a communication pin and a control pin; The charging box communication terminal is used to electrically connect to the communication pin of the charging box micro control unit, and the charging control signal terminal is used to electrically connect to the control pin of the charging box micro control unit.

8. A charging box, characterized in that: Includes a charging box switching circuit as described in any one of claims 1 to 7.

9. A wireless headset system, characterized in that: It comprises a charging box and a wireless headset, wherein the charging box comprises the charging box switching circuit as described in any one of claims 1 to 7.

10. The wireless headset system according to claim 9, wherein: The wireless headset includes a wireless headset switching circuit, and the wireless headset switching circuit includes: An earphone terminal, the earphone terminal being used to electrically connect to an external pin of an earphone; An earphone communication terminal, the earphone communication terminal being used to electrically connect to an earphone microcontroller unit; an earphone communication circuit, the earphone communication circuit being connected in series between the earphone terminal and the earphone communication end, the earphone communication circuit being configured to transmit a communication signal to the earphone communication end in response to a communication signal from the earphone terminal, the earphone communication circuit being further configured to transmit a communication signal to the earphone terminal in response to a communication signal from the earphone communication end, and being further configured to cut off a connection between the earphone terminal and the earphone communication end in response to a charging voltage on the earphone terminal; An earphone power supply terminal, the earphone power supply terminal is used to provide power to the battery in the wireless earphone; an earphone charging circuit, the earphone charging circuit being connected in series between the earphone terminal and the earphone power supply terminal; The headphone charging circuit is used to respond to the charging voltage on the headphone terminal to connect the headphone terminal and the headphone power supply terminal. The headphone charging circuit is also used to respond to the communication signal voltage on the headphone terminal to cut off the headphone terminal and the headphone power supply terminal.

11. The wireless headset system according to claim 10, wherein: The charging box switching circuit includes: a first voltage terminal, the first voltage terminal being used to provide a first voltage; a first transistor, wherein the first transistor is an N-type metal oxide semiconductor field effect transistor (MOSFET), a source of the first transistor is electrically connected to the charging box communication terminal, and a drain of the first transistor is electrically connected to the charging box connection terminal; a first resistor, wherein the gate of the first transistor is electrically connected to the first voltage terminal through the first resistor; a second resistor, the second resistor being connected in series between the gate and the source of the first transistor; The earphone communication circuit comprises: a fourth voltage terminal, the fourth voltage terminal being used to provide a high voltage among the communication signal voltages; a sixth transistor, the sixth transistor being an N-type MOSFET, the drain of the sixth transistor being electrically connected to the headphone terminal, the source of the sixth transistor being electrically connected to the headphone communication terminal, and the gate of the sixth transistor being electrically connected to the fourth voltage terminal; an eighth resistor, the eighth resistor being connected in series between the fourth voltage terminal and the source of the sixth transistor; The earphone charging circuit includes: a fifth voltage terminal, configured to provide the first voltage; a seventh transistor, wherein the seventh transistor is a P-type MOSFET, a source of the seventh transistor is electrically connected to the headphone terminal, a drain of the seventh transistor is electrically connected to the headphone power terminal, and a gate of the seventh transistor is electrically connected to the fifth voltage terminal.

12. The wireless headset system according to claim 11, wherein: The earphone communication circuit further includes a ninth resistor, and the gate of the sixth transistor is electrically connected to the fourth voltage terminal through the ninth resistor.

13. The wireless headset system according to claim 11, wherein: The earphone charging circuit further includes a tenth resistor, and the seventh transistor is electrically connected to the fifth voltage terminal through the tenth resistor.

14. The wireless headset system according to claim 11, wherein: The wireless earphone switching circuit may further include an electrostatic discharge circuit, and the earphone terminal is grounded through the electrostatic discharge circuit.

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