WO2019196054A1

WO2019196054A1 - Control device for earphones and wired earphones

Info

Publication number: WO2019196054A1
Application number: PCT/CN2018/082795
Authority: WO
Inventors: 段红亮; 杨旺旺; 刘畅
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2018-04-12
Filing date: 2018-04-12
Publication date: 2019-10-17
Also published as: CN108521872B; CN108521872A

Abstract

Provided are a control device for earphones and wired earphones. The control device comprises: a voltage protection circuit; when earphones are inserted into a terminal device, the voltage protection circuit is connected to a power supply end of the terminal device by means of a microphone end of the earphones, and the voltage protection circuit is used to receive the voltage outputted by the power supply end by means of the microphone end and output a first voltage, the voltage outputted by the power supply end being greater than or equal to the first voltage. In an embodiment of the present invention, by means of internally providing a voltage protection circuit for earphones, a back end circuit of the earphones may be prevented from being damaged when the voltage outputted by a power supply end of a terminal device is too great.

Description

Headphone control and wired headset

Technical field

Embodiments of the present invention relate to the field of electronic technologies, and, more particularly, to a control device for a headset and a wired headset.

Background technique

With the rise of wearable health aids, heart rate measurement has become the most common physiological state detection index. The ear has abundant capillaries and has great advantages in measuring physiological signals such as heart rate, blood pressure and blood oxygen. The basic conditions of measurement. There is a wireless heart rate detection earphone in the current market. Specifically, the headset is connected to the smart terminal through Bluetooth, and the heart rate data or the calculation result is transmitted to the mobile phone. However, such headphones require a built-in battery and also require charging, and the cost is high and the price is expensive. The traditional wired earphones generally only have the basic functions of voice transmission, music playback, and button operation. If the heart rate detection function is integrated in the wired earphone, due to the limitation of the power supply mode of the wired earphone system, the power supply of the mobile phone paired with the earphone is cited. The output voltage of the foot is low, which is not enough to provide enough power for the heart rate detection function. However, if the output voltage of the mobile phone is increased (such as 5V), when the earphone is inserted into the mobile phone, the circuit at the back end may be too high. The voltage is damaged.

Summary of the invention

In order to solve the above problems, the present application provides a control device for a headset and a wired headset, which can prevent the back end circuit of the earphone from being damaged when the voltage output from the power supply terminal of the terminal device is excessive.

In one aspect, a headset control device is provided, including:

a voltage protection circuit, when the earphone is inserted into the terminal device, the voltage protection circuit is connected to the power supply end of the terminal device through a microphone end of the earphone, and the voltage protection circuit is configured to receive the power supply through the microphone end The voltage outputted by the terminal outputs a first voltage, wherein the voltage output by the power supply terminal is greater than or equal to the first voltage.

In the embodiment of the present invention, by embedding a voltage protection circuit for the earphone, when the voltage from the power supply terminal of the terminal device is higher than the first voltage, the voltage from the terminal device can be converted into the first voltage output. That is, when the voltage output from the power supply terminal is excessively large, the voltage limiting process of the voltage protection circuit can avoid damage to the back end circuit of the voltage protection circuit.

In another aspect, a wired headset is provided, comprising: the control device of the first aspect.

DRAWINGS

1 is a schematic structural view of a wired earphone with a 3.5 mm audio connector according to an embodiment of the present invention.

2 is a diagram showing an example of a 3.5 mm audio interface of a terminal device corresponding to a 3.5 mm audio connector according to an embodiment of the present invention.

3 is a schematic block diagram of a biometric detection module in accordance with an embodiment of the present invention.

4 and FIG. 5 are schematic diagrams showing the design positions of the biometric detecting module in the earplug according to the embodiment of the present invention.

FIG. 6 is a schematic structural diagram of an earphone with a biometric detecting module built in an embodiment of the present invention.

7 is a schematic diagram showing the position of a backflow detection control circuit of an earphone according to an embodiment of the present invention.

Figure 8 is a diagram showing the position of a supply voltage control circuit of an earphone according to an embodiment of the present invention.

9 is a schematic diagram showing the position of a voltage protection circuit of an earphone according to an embodiment of the present invention.

Figure 10 is a schematic illustration of the position of a signal isolation circuit of an earphone in accordance with an embodiment of the present invention.

Figure 11 is a schematic block diagram of an earphone in accordance with an embodiment of the present invention.

FIG. 12 is a voltage waveform diagram of the power supply terminal when the power supply terminal of the terminal device is in a sleep state according to an embodiment of the present invention.

FIG. 13 is a voltage waveform diagram of the power supply terminal after the power take-off circuit is operated by the terminal device that is dormant at the power supply end according to the embodiment of the present invention.

Figure 14 is a diagram showing an example of a circuit design of an earphone according to an embodiment of the present invention.

Figure 15 is a diagram showing an example of the structure of a first voltage detecting control circuit in accordance with an embodiment of the present invention.

Figure 16 is a block diagram showing another example of the first voltage detecting control circuit of the embodiment of the present invention.

Figure 17 is a diagram showing an example of another circuit design of the earphone of the embodiment of the present invention.

detailed description

The technical solutions of the embodiments of the present invention are described below with reference to the accompanying drawings.

1 is a schematic structural view of a wired earphone with a 3.5 mm audio connector according to an embodiment of the present invention. 2 is a diagram showing an example of a 3.5 mm audio interface of a terminal device corresponding to a 3.5 mm audio connector 110b according to an embodiment of the present invention. As shown in FIG. 1, the wired earphone 100 includes a 3.5 mm audio connector 110b, a headphone cable 120, a wire control board 130, and an earphone 140. Among them, the 3.5mm audio connector 110b can be divided into: a microphone (MIC) communication connector 111b, a device ground (GND) potential connector 112b, a right earphone speaker connector 113b, and a left earphone speaker connector 114b. When the 3.5mm audio connector 110b shown in FIG. 1 is connected to the smart terminal (ie, the earphone is inserted into the smart terminal), the microphone (MIC) communication connector 111b, the device ground (GND) potential connector 112b, and the right earphone speaker shown in FIG. The connector 113b and the left earphone speaker connector 114b are respectively connected to the microphone (MIC) communication interface 111a, the device ground (GND) interface 112a, the right speaker interface 113a and the left speaker interface 114a shown in FIG. 2, wherein the microphone communication interface 111a, the device The ground interface 112a, the right speaker interface 113a, and the left speaker interface 114a constitute the audio interface 110a of the terminal device. In practice, a digital to analog converter (DAC) converts a digital signal into an analog signal (in the form of current, voltage, or charge) to communicate with the headset or to power the headset. Further, the microphone communication interface 111a is connected to the internal level 152 of the terminal device, and the internal level 152 provides a power supply voltage to the earphone through the microphone communication interface 111a. In some embodiments, the microphone communication interface 111a may also be referred to as a terminal. For the convenience of description, the power supply terminal of the device is used as an example. It should be understood that the conventional wired earphone generally has only the basic functions of voice transmission, music playback, and button operation. The wired headset 100 in the embodiment of the present invention may have a biometric detection module built therein, and the biometric detection module may be any module that can detect the physiological state of the human body. For example, it may be a biometric detection module 711, a pressure detection module, a wear detection module, a blood pressure detection module, a body temperature detection module, a blood glucose detection module, a blood lipid detection module, and the like, and other physiological signals or circuit modules. It should also be understood that the application is not limited to earbuds and is merely illustrative herein. The wired headset 100 in the embodiment of the present invention may have a biometric display module for displaying the detection result of the biometric detection module.

3 is a schematic block diagram of a biometric detection module in accordance with an embodiment of the present invention. As shown in FIG. 3, the biometric detection module 200 can include an acquisition module 220 and a calculation control module 210. The acquisition module 210 is configured to collect the original heart rate data (or the processed heart rate data, or the calculated heart rate result); the calculation control module 210 can be used to process and calculate the heart rate data collected by the collection module 220; the calculation control module The 210 can also be used to communicate with the mobile phone and the acquisition module 220. The calculation control module 210 can also be used to control the working mode of the entire module or circuit in the biometric detection module 200 or the biometric detection module 200. In one embodiment, the acquisition module 220 can include a heart rate sensor 221, a light emitting diode (LED) 224, an acceleration sensor 222, and an optical design module 225, which can include a photodiode (PD) 223. The heart rate sensor 221 controls the light-emitting diode 224 to emit light, and the emitted light passes through the skin tissue and is transmitted to the photodiode 223. The heart rate sensor 221 processes the optical signal received by the photodiode 223, and quantizes the optical signal into an electrical signal. The analog to digital conversion circuit converts to a digital signal and finally sends it to a standard digital communication interface. For example, I2C interface, SPI interface. In an embodiment, the calculation control module 210 may include a power supply control module 211, a Micro Control Unit (MCU), and a Digital Signal Processing (DSP) 212. The calculation control module 210 can be used to control the power supply of the acquisition module 220, the operation mode, calculate and indicate the measured heart rate result, and the like.

4 and 5 are schematic diagrams showing the design position of the biometric detection module 200 (especially the acquisition module 220) in the earplug. As shown in FIG. 4, the earplug 140 shown in FIG. 1 in the embodiment of the present invention may include: an earplug machine member 141 and an acquisition module 220 as shown in FIG. Specifically, the earphone component 141 may include: a rear shell trim, a rear shell, a front shell, and a silicone sleeve. As shown in FIG. 5, the earplug 140 may further include the speaker module 142 and a plurality of wires 123c connected to the speaker module 142 and the acquisition module 220, respectively. The biometric detection module 200 (especially the acquisition module 220) in the embodiment of the present invention may be disposed at any position on the wired earphone that can be close to the ear.

FIG. 6 is a schematic structural diagram of an earphone incorporating a biometric detecting module 200 (particularly, the collecting module 220) according to an embodiment of the present invention. As shown in FIG. 6 , the acquisition module 220 is disposed on the left earplug 340 b , and the calculation control module 210 illustrated in FIG. 3 may be disposed in the wire control panel 330 . The beam splitter 322 is for dividing the third wire harness 321 into a first wire harness 323-B and a second wire harness 323-A through which the first wire harness 323-B is connected to the third wire harness 323-C. It should be understood that the connection relationship between the various functional modules shown in FIG. 6 is only an exemplary description, and is not specifically limited in the embodiment of the present invention. For example, as shown in FIG. 6, the acquisition module 220 is disposed on the left earbud 340b. In other embodiments, the acquisition module 220 can also be disposed on the right earbud 340a, or both on the right earbud 340a and the left earbud 340b, and the like. For another example, as shown in FIG. 6 , the calculation control module 210 can be disposed on the wire control board 330 . In other embodiments, the calculation control module 210 can be disposed on the right earbud 340a and/or the left earplug 340b, and the calculation control module 210 can also be integrated into the earphone alone or the like. The embodiment of the invention is not specifically limited.

Since the earphone in the embodiment of the present invention does not require a battery, there is no need to charge, and it is not necessary to carry a charging cable or a charger. Moreover, it is easy to use and can be used by inserting a target device (for example, a mobile phone), thereby reducing the production cost of the earphone. Further, the earphone in the embodiment of the present invention can support heart rate measurement on the earphone and indicate the heart rate interval. However, when an earphone integrated with a biometric detection module is inserted into a terminal device (for example, a mobile phone), only the microphone (MIC) line (ie, the microphone end of the earphone) has a current, that is, the mobile phone system receives the power supply voltage only through the microphone end of the earphone. When the microphone terminal current of the earphone is too large or too small, it will affect the normal operation of the earphone. In addition, the audio signal generated by the microphone is also transmitted to the mobile phone through the MIC line on the mobile phone. Therefore, for a device that transmits signals through a power line (such as a mobile phone output MIC line), the signal to be transmitted on the power line cannot be attenuated, and the power fluctuation generated by the system operation cannot interfere with the signal on the power line. The built-in biometric detection module in the earphone is likely to cause interference between the two signals, thereby reducing the user experience.

On the one hand, in order to solve the problem that the power of the microphone terminal of the earphone is too small or the power supply capability of the earphone plug of the terminal device is insufficient, in the embodiment of the present invention, a storage circuit can be disposed in the earphone for storing the microphone from the earphone. The charge at the end. In this way, even if the power supply capability of the earphone plug of the terminal device is insufficient, the energy storage circuit can normally supply power to the earphone, preventing the earphone from excessively consuming a large current, causing the power supply terminal voltage to drop excessively, thereby affecting the normal voice transmission of the earphone. Features.

On the other hand, in order to ensure that the charge stored in the tank circuit is not reversely discharged, in the embodiment of the invention, a backflow detection control circuit can be configured for the earphone. As shown in FIG. 7, the control device 400 for the earphone may include a backflow detection control circuit 420. The microphone end 410 of the earphone is connected to the energy storage circuit 430 of the earphone through the backflow detection control circuit 420. The reverse flow detection control circuit 420 is used for Comparing the voltage in the tank circuit 430 with the voltage of the microphone terminal 410 of the earphone, and controlling the electrical connection or the electrical disconnection between the tank circuit 430 and the microphone terminal 410 according to the comparison result of the backflow detection control circuit 420. .

On the other hand, in the embodiment of the present invention, the earphone can be further configured in the embodiment of the present invention, in order to ensure that the power supply voltage of the earphone is insufficient to drive the various modules or circuits in the earphone to work normally even in the presence of the energy storage circuit. A supply voltage control circuit that can control a supply voltage or power consumption of at least one module or circuit in the earphone. Preferably, the supply voltage control circuit can control a supply voltage of the signal processing circuit in the earphone. For example, as shown in FIG. 8, the control device 400 for the earphone may include a power supply voltage control circuit 440 through which the microphone terminal 410 of the earphone is connected to the input end of the energy storage circuit 430 of the earphone, the energy storage. The output of the circuit 430 is coupled to the signal processing circuit 450 by a supply voltage control circuit 440 for obtaining the voltage condition of the microphone terminal 410 of the earphone and/or the energy storage condition of the energy storage circuit 430 of the earphone. And controlling the supply voltage of the signal processing circuit 450 of the earphone according to the voltage condition of the microphone terminal 410 and/or the energy storage condition of the energy storage circuit 430 of the earphone. In other words, the supply voltage control circuit 440 is configured to acquire the voltage of the microphone terminal of the earphone and/or the voltage state of the energy storage circuit, thereby controlling the power supply voltage or operation mode of each module or circuit in the earphone.

Correspondingly, in the embodiment of the present invention, a voltage protection circuit can be built in the earphone for the problem that the current of the microphone terminal of the earphone is too large or the power supply capability of the earphone plug of the terminal device is too large. For example, as shown in FIG. 9, the control device 400 of the earphone may include a voltage protection circuit 520. When the earphone is inserted into the terminal device, the voltage protection circuit 520 is connected to the power supply end of the terminal device through the microphone end 510 of the earphone. The protection circuit 520 is configured to receive the voltage output by the power supply terminal through the microphone terminal 510 and output a first voltage, wherein the voltage output by the power supply terminal is greater than or equal to the first voltage. The voltage protection circuit can convert the voltage outputted by the power supply terminal to the first voltage that is less than or equal to the output voltage of the power supply terminal, and prevent the circuit of the back end from being damaged when the voltage outputted by the power supply terminal is too large, thereby affecting the normal operation of the earphone. As an example, when the voltage outputted by the power supply terminal is higher than the threshold voltage, the first voltage is equal to the threshold voltage, and when the voltage outputted by the power supply terminal is lower than the threshold voltage, the first voltage is equal to the voltage output by the power supply terminal. In other words, when the voltage outputted by the power supply terminal is higher than the threshold voltage, the voltage protection circuit 520 can be used to output the threshold voltage. When the voltage output by the power supply terminal is lower than the threshold voltage, the voltage protection circuit 520 can be used. The voltage output from the power supply terminal is output. For example, the threshold voltage is 2.8 volts. It should be understood that the voltage protection circuit 520 in the embodiment of the present invention is intended to perform a voltage limiting process on the voltage received by the microphone terminal of the earphone. When the voltage output by the power supply terminal is higher than the threshold voltage, the first voltage is equal to the threshold voltage. When the voltage outputted by the power supply terminal is lower than the threshold voltage, the first voltage is equal to the voltage outputted by the power supply terminal, which is merely an exemplary description. For example, in other embodiments, the first voltage may be a voltage after the voltage output from the power supply terminal is subjected to a voltage limiting process according to a certain proportional relationship.

In addition, in order to ensure that the power fluctuation caused by the system work does not attenuate the signal to be transmitted on the power line (such as the mobile phone output MIC line), in this application, a signal isolation circuit may be built in the earphone so that the power supply generated during the operation of the earphone does not fluctuate. It will interfere with the signal transmitted on the power line. In an optional embodiment, as shown in FIG. 10, the control device 400 for the earphone may include a signal isolation circuit 630 through which the microphone end 610 of the earphone is connected to one end of the signal isolation circuit 630, wherein The sound pickup circuit 620 is configured to convert the received sound signal into an electrical signal. The signal isolation circuit 630 is for isolating interference between the electrical signal and a circuit (generated power supply fluctuation) connected to the other end of the signal isolation circuit 630.

The connection relationship between the voltage protection circuit, the reverse current detection control circuit, the signal isolation circuit and the power supply voltage control circuit mentioned above is exemplified in the following with reference to the accompanying drawings:

11 is a schematic block diagram of a structure of an earphone according to an embodiment of the present invention. The solid line in FIG. 11 may indicate an electrical connection, and the broken line may indicate a communication connection. Specifically, the connection relationship of the earphone including various circuits or modules may be as follows: the microphone end of the earphone is sequentially electrically connected to the first voltage through the voltage protection circuit 701, the reverse current detection control circuit 702, the signal isolation circuit 703, and the energy storage circuit 704. The detection control circuit 705 is electrically connected to the signal processing circuit 710, the sound pickup circuit 709, and the biometric detection module 711 by the first voltage detection control circuit 705, respectively. Taking the connection between the signal processing circuit 710 and the first voltage detection control circuit 705 as an example, the first voltage detection control circuit 705 is connected to the signal processing circuit 710 by a solid line. It can be understood that the first voltage detection control circuit 705 is electrically connected. Connected to the signal processing circuit 710. The first voltage detection control circuit 705 is bidirectionally connected to the signal processing circuit 710 by a broken line. It can be understood that the first voltage detection control circuit 705 and the signal processing circuit 710 can perform bidirectional communication. In actual operation, the signal processing circuit 710 can control the conduction or disconnection of the electrical connection between the first voltage detection control circuit 705 and the signal processing circuit 710 by transmitting a control signal to the first voltage detection control circuit 705. Broken. Similarly, as shown in FIG. 11, the power take-off circuit 707 can be communicatively coupled to the microphone end of the earphone and the signal processing circuit 710, and the sound pickup circuit 709 can be communicably connected to the microphone end of the earphone, the biometric detection module 711 and the creature. The feature display module 712 can be communicatively coupled to the signal processing circuit 710, respectively, and the biometric detection module 711 can also be communicatively coupled to the microphone end of the headset via the communication circuit 706.

It should be understood that the connection relationship of each module or circuit in the earphone shown in FIG. 11 is only an example. In other embodiments, the earphone may include a partial circuit or module as shown in FIG. 11, for example, does not include the backflow detection control circuit 702. Or the first voltage detection control circuit 705 or the like. For another example, the microphone end of the earphone can be communicably connected to the signal processing circuit 710 through the voltage protection circuit 701, that is, the operation mode (for example, on or off) of the voltage protection circuit 701 is controlled by the signal processing circuit 710.

For the voltage control of the microphone end of the earphone, the voltage protection circuit 701 and the power take-off circuit 707 are introduced in this embodiment. On the one hand, when a terminal device (for example, a mobile phone) paired with the earphone outputs a relatively high voltage (for example, 5V), the voltage protection circuit 701 in the embodiment of the present invention can be used to prevent the circuit at the back end from being damaged by excessive voltage. . Taking the terminal device as the mobile phone as an example, in this embodiment, the 3.5 mm headphone port of the mobile phone can be used as the connector. The microphone (MIC) power supply pin in the phone's headphone port can be used to power the entire headset and the headset to transmit data to the phone. The right channel (R) of the phone can be used as a port for the phone to send commands to the headset. The voltage protection circuit 701 in this embodiment may be provided with a threshold voltage. When the input voltage of the voltage protection circuit 701 (ie, the output voltage of the power supply terminal of the terminal device) is higher than the threshold voltage, the voltage protection circuit 701 outputs a threshold voltage. When the input voltage is higher than the threshold voltage, the output voltage of the voltage protection circuit 701 is the same as the input voltage. That is, the voltage protection circuit 701 is used to limit the output voltage of the power supply terminal of the mobile phone. For example, if the maximum operating voltage of the earphone is 3V and the output voltage of the power supply terminal of the mobile phone is 5V, it may cause damage to the earphone. In this embodiment, the threshold voltage of the voltage protection circuit 701 is set to 2.8V. When the power supply terminal of the mobile phone outputs 5v, the maximum voltage of the earphone is 2.8V, which is a function of protecting the earphone circuit. . If the output voltage of the power supply terminal of the mobile phone is lower than 2.8V, the voltage provided by the voltage protection circuit 701 to the subsequent circuit is the output voltage of the power supply terminal of the mobile phone.

On the other hand, when the output voltage of the power supply terminal of the terminal device is too low, the power take-off circuit 707 in this embodiment can send a third signal to the terminal device inserted by the earphone, and the third signal is used to stimulate the increase of the terminal device. The voltage output from the power supply terminal. In an alternative embodiment, the power take-off circuit 707 can be used to transmit a signal to the terminal device (such as pulling the voltage of the microphone terminal of the mobile phone), which is used to trigger the power terminal of the terminal device to output a high voltage. Taking the terminal device as the mobile phone as an example, for example, when the voltage of the microphone end of the mobile phone shown in FIG. 12 is too low, the power take-off circuit 707 can pull down the voltage of the microphone end of the mobile phone for a period of time (T ms as shown in FIG. 13). ), used to trigger the mobile phone to increase the output capability of the microphone end of the mobile phone again. It should be noted that the sound pickup circuit 709 shown in FIG. 11 can be used to receive an external sound signal and then converted into an electrical signal for transmission to the terminal device. In an alternative embodiment, to save power, the power to the sound pickup circuit 709 can be controlled by the signal processing circuit 710 or other circuitry or modules.

It should be understood that the case where the output voltage of the power supply terminal of the terminal device is too low includes, but is not limited to, the following situation: the power supply terminal of the terminal device (such as the voltage of the microphone terminal output by the 3.5 mm port of the mobile phone) is unstable. When the terminal device does not use the microphone, that is, the microphone end of the terminal device sleeps (expressed as the output voltage decreases and the internal resistance increases). The voltage is too low when the earphone button is pressed. For example, the power supply mode of the 3.5 mm interface of the mobile phone may include at least one of a non-power supply mode, a strong power supply mode, and a weak power supply mode. When the mobile phone 3.5mm interface is in the strong power supply mode, the sound pickup circuit 709 can work normally. When the mobile phone 3.5mm interface is in the weak power supply mode, the sound pickup circuit 709 may not work normally. The sound pickup circuit 709 in the embodiment of the present invention may be a microphone circuit, or may be another type of module for a call, which is not specifically limited in the embodiment of the present invention. Optionally, when the mobile phone interface is in the strong power supply mode, the internal level of the mobile phone interface (152 shown in FIG. 2) is generally higher than the 1.6V power supply voltage; and when the mobile phone interface is in the weak power supply mode, the internal of the mobile phone interface The level may be lower than 1.8v; it should be understood that the power supply mode of different mobile phones may be different. The above-mentioned numbers are only illustrative, and the embodiments of the present invention are not limited. For example, when the mobile phone interface is in the weak power mode, the internal level of the mobile phone interface may be lower than 1.7v. In actual work, when the corresponding mobile phone 3.5mm interface is in the strong power supply mode, it can provide sufficient power supply voltage for the earphone. However, when the handset 3.5mm interface is in the weak power mode, the headset's supply voltage is the sleep voltage (eg, from 2.7V operating voltage to 1.4v sleep voltage). It should be noted that the case where the mobile phone interface is in the strong power supply mode may include: the wired headset is inserted into the mobile phone, and the microphone related application is opened (such as a call); or, when no microphone application is opened, the sound pickup circuit 709 is idle. State; for example, a period of time after the wired headset is inserted; for example, for a period of time after the button is pressed; or for a period of time after the microphone-related application is stopped. Correspondingly, in other time periods, the mobile phone interface is in a weak power supply mode.

For the voltage detection of the microphone end of the earphone, a second voltage detection control circuit 708 is introduced in the embodiment, and the second voltage detection control circuit 708 is configured to detect the power supply end of the terminal device in time (such as the voltage of the microphone end outputted by the 3.5 mm port of the mobile phone). ), that is, the microphone terminal voltage of the earphone, when detecting that the microphone terminal voltage of the earphone is too low, the earphone can enter the corresponding working mode and perform corresponding processing, such as entering the low power mode, and performing related actions to trigger the terminal device. A higher voltage is output (eg, the trigger power take-off circuit 707 operates). In other words, the second voltage detection control circuit 708 is configured to measure the voltage condition of the microphone terminal of the earphone, and output a signal for characterizing the state of the microphone terminal supply voltage of the mobile phone to the signal processing circuit 710, so that the signal processing circuit is based on the signal. Let the headset enter the corresponding working mode and handle it accordingly. Taking the sound pickup circuit 709 as an example, the second voltage detection control circuit 708 can generate and send a fourth signal to the signal processing circuit 710 for indicating the voltage condition of the microphone terminal of the earphone, and the signal processing circuit 710 receives After the fourth signal, the power take-off circuit 709 can be controlled based on the fourth signal.

Taking the terminal device as the mobile phone as an example, the power supply model of the power supply end of the mobile phone in this embodiment may be a voltage source + a resistor, that is, the power supply end of the mobile phone can provide power and receive signals. Therefore, the energy storage circuit 704 in the embodiment of the present invention can store the weak current outputted by the power supply end of the mobile phone, and start the subsequent circuit operation when the charge storage is sufficient.

In conjunction with the energy storage circuit 704, on the one hand, a reverse current detection control circuit 702 is introduced in the embodiment of the present invention, which can be used to control the flow direction of the current. Specifically, when the output voltage of the power supply end of the mobile phone is high, In order to provide power to the system, when the output voltage of the power supply terminal of the mobile phone is low, the charge of the energy storage circuit 704 is prevented from being lost. In other words, the backflow detection control circuit 702 in this embodiment can be used to limit the one-way flow of current, that is, only allow current to flow from the power supply end of the mobile phone to the rear circuit, and prevent current from flowing from the rear circuit to the power supply end of the mobile phone.

On the other hand, a first voltage detection control circuit 705 is introduced in the embodiment of the present invention, which can be used to detect the voltage of the energy storage circuit. Specifically, when the first voltage detection control circuit 705 detects the energy storage circuit 704 When the voltage reaches the normal operating voltage of the system, the voltage of the microphone terminal and the charge stored in the tank circuit 704 supply power to the various modules or circuits in the headset. When the first voltage detection control circuit 705 detects that the voltage on the energy storage circuit 704 is too low, it sends an outgoing voltage signal to some modules or circuits in the earphone or the earphone to remind the system that the voltage is insufficient for the system to perform corresponding processing ( For example, enter the low power mode, or control the supply voltage of some modules or circuits in the headset. In other words, the first voltage detection control circuit 705 can be used to detect the charge voltage of the tank circuit 704, and can provide the back circuit of the tank circuit 704 when the storage voltage of the tank circuit 704 is detected to reach a certain threshold. Electrical energy, further, may also output a signal to signal processing circuit 710 which characterizes how much charge is stored by tank circuit 704.

In addition, in actual communication, for a device that transmits signals through a power line (such as a mobile phone output MIC line), it is necessary to avoid attenuation of a signal to be transmitted on the power line, and also to avoid power fluctuations generated by the operation of the earphone to interfere with the power supply. Signal on the line. The signal isolation circuit 703 in the embodiment of the present invention can make the two signals generate an isolation effect, that is, can prevent the signal output from the isolated sound pickup circuit 709 (the signal is converted by the sound and transmitted to the mobile phone) to be attenuated, and can prevent the The power supply fluctuation caused by the operation of the rear circuit of the signal isolation circuit 703 affects the output signal of the sound pickup circuit 709.

Taking the terminal device as the mobile phone as an example, the communication circuit 706 in this embodiment is responsible for the communication function between the mobile phone and the earphone. The communication circuit 706 collects the data (heart rate value, system status, etc.) of the signal processing circuit 710 and the data (heart rate raw data, etc.) of the biometric detection module 711, and transmits the data to the mobile terminal through the MIC power supply end of the mobile phone. At the same time, the data sent by the mobile terminal (transmitted to the communication circuit 706 through the right channel line of the mobile phone) is correspondingly sent to the signal processing circuit 710 and the biometric detection module 711. Optionally, the communication circuit 706 may further include a button signal to send the button signal to the mobile terminal. The signal processing circuit 710 can be the control center of the entire earphone. Specifically, the signal processing circuit 710 can be used to read the original heart rate data of the biometric detection module 711 and used to calculate the heart rate value. The signal processing circuit 710 can also be used to control the biometric display module 712 to display the value of the biometric or the interval in which the biometric is located. The signal processing circuit 710 can also be used to control the power supply of the first voltage detection control circuit 705. The signal processing circuit 710 can also be used for data exchange with the communication circuit 706. The signal processing circuit 710 can also be configured to receive the output signal of the second voltage detection control circuit 708 to determine the voltage condition of the microphone terminal of the earphone. The signal processing circuit 710 can also be used to control the power take-off circuit 707 to work, triggering the microphone terminal of the mobile phone to output a high voltage. In addition, the biometric detection module 711 can be placed close to the user's skin to obtain the user's original heart rate data, and the biometric display module 712 displays the current user's displayed biometric value or the interval in which the biometric is located.

In the actual operation, taking the terminal device as the mobile phone as an example, the workflow of the earphone may include: when the earphone is inserted into the 3.5mm earphone hole of the mobile phone end, the power supply end of the mobile phone outputs a voltage, and the voltage protection circuit 701 is used to limit the output voltage of the mobile phone and prevent the mobile phone from being used. The output voltage is too high, damaging the back-end circuit. Since the entire earphone is inserted for the first time, there is no charge storage in the tank circuit 704, and the current flows through the voltage protection circuit 701, flows through the backflow detection control circuit 702, and the signal isolation circuit 703 flows into the tank circuit 704 for storage. When the first voltage detection control circuit 705 detects that the voltage of the tank circuit 704 reaches a threshold voltage (eg, 2V), the tank circuit 704 supplies power to the module or circuit at the back end of the tank circuit 704, such as the signal processing circuit 710, and the sound. The pickup circuit 709 and the biometric detection module 711 and the like. After the module or circuit at the back end of the tank circuit 704 is powered, it starts normal operation. Further, after the signal processing circuit 710 obtains the power supply, the biometrics detection module 711 is controlled and the corresponding heart rate raw data is acquired, and the heart rate signal is calculated and displayed by the biometric display module 712.

When a button is pressed, the communication circuit 706 generates a button signal to lower the power supply voltage of the microphone end of the mobile phone. In one aspect, the second voltage detection control circuit 708 transmits a low voltage signal on the power supply voltage of the microphone terminal of the mobile phone to the signal processing circuit 710, and the signal processing circuit 710 performs corresponding processing to save power consumption, such as stopping biometric detection and display. The power supply to the sound pickup circuit 709 is turned off. On the other hand, when a button signal is generated, the power supply voltage of the microphone terminal of the mobile phone is lower than the voltage of the energy storage circuit 704, and the reverse current detection control circuit 702 disconnects the path to prevent the charge of the energy storage circuit 704 from flowing back to the mobile phone. Mike end. When the mobile phone system is using the microphone, the sound pickup circuit 709 converts the sound signal into an electrical signal, which is transmitted to the output end of the voltage protection circuit 701 for transmission to the microphone end of the mobile phone. Due to the presence of the backflow detection control circuit 702 and the signal isolation circuit 703, the output signal of the sound pickup circuit 709 is not attenuated. At the same time, the power fluctuation generated when the earphone works is also not transmitted to the microphone end of the mobile phone due to the presence of the signal isolation circuit 703. It should be noted that for some mobile phones, when the mobile phone system does not use a microphone, the microphone end may sleep, which means that the output voltage becomes lower, the internal resistance increases, and the power supply capability becomes weak. At this time, on the one hand, the reverse current detection control circuit 702 can be used to prevent the charge of the energy storage circuit 704 from flowing to the microphone end of the mobile phone. On the other hand, the second voltage detection control circuit 708 detects the signal and sends a signal to the signal processing circuit 710. The signal processing circuit 710 detects that the mobile phone microphone is powered to sleep, and then sends a power take signal to the power take-off circuit 707 to take power. The circuit 707 triggers the mobile phone to cause the voltage outputted by the microphone terminal of the mobile phone to be a high voltage.

In summary, in the embodiment of the present invention, by introducing the power taking circuit 707, the second voltage detecting control circuit 708, the backflow detecting control circuit 702, and the first voltage detecting control circuit 705, when the voltage of the microphone end of the earphone is too low, The voltage output from the power supply terminal of the terminal device can be excited by the power take-off circuit 707. Moreover, the signal processing circuit 710 can measure the voltage condition of the microphone terminal of the earphone and/or the charge state of the energy storage circuit measured by the first voltage detection control circuit 705 according to the second voltage detection control circuit 708, so that the earphone enters the corresponding working mode. And the corresponding processing, and then the power is properly distributed for each module or circuit in the earphone. In addition, the reverse current detection control circuit 702 can effectively prevent the charge in the energy storage circuit from being lost to the power supply end of the mobile phone, thereby avoiding waste of the charge in the energy storage circuit. Finally, the signal isolation circuit 703 can effectively reduce the interference between the sound pickup circuit 709 and the back end circuit.

It should be understood that the signal processing circuit 710 shown in FIG. 11 may control the signal according to the detection result of the module or circuit (for example, the second voltage detection control circuit 708 and/or the first voltage detection control circuit 705) in the earphone. The processing circuit 710 and the supply voltages of other circuits or modules in the headset (eg, the power take-off circuit 707, the biometric detection module 711, and the biometric display module 712). The signal processing circuit 710 can be a Micro Control Unit (MCU)/Digital Signal Processing (DSP) for controlling the power supply, working mode and data of each module or circuit in the earphone. More specifically, It is used to control the working mode (ie, power consumption) of each circuit or module in the wired headset according to actual needs. The voltage protection circuit 701 of the embodiment of the present invention is for controlling the output voltage of the microphone end of the earphone and the power supply end of the terminal device, that is, the input voltage of the earphone. It should be understood that the calculation control module 210 shown in FIG. 3 is used to control the power supply, operation mode, calculation, and indication of the measured heart rate result of the acquisition module 220 as an exemplary description. However, the embodiment of the invention is not limited thereto. For example, in other embodiments, the calculation control module 210 can also be integrally disposed in the signal processing circuit 710. That is, the acquisition module 220 can be separately designed. After the collection module 220 collects data, the collected data can be collected. The signal processing circuit 710 is sent to the signal processing circuit 710, and the signal processing circuit 710 controls the power supply, operation mode of the acquisition module 220, calculates and indicates the measured heart rate result.

It should also be understood that the various circuits or modules shown in FIG. 11 can be produced separately as the control device or circuit of the earphone, or can be partially integrated into the control device of the earphone, or can be integrated on one workpiece as the overall control device for the earphone. The embodiment of the present invention is not specifically limited. For example, the voltage protection circuit 701 can be produced as part of a wired headset or integrated on the signal processing circuit 710 for production, i.e., as part of the signal processing circuit 710. 6, the respective circuits or modules shown in FIG. 11 may be separately or integratedly disposed in the wire control board of the wired earphone, or may be separately or integrally disposed on the earplugs (the right earplug 340a and the left earplug 340b). In other embodiments, the various circuits or modules shown in FIG. 11 can be split into a plurality of modules or circuits respectively disposed on the wire control plate 330, the left earplug 340b, and the right earplug 340a. The embodiment of the invention is not specifically limited. Further, each module or circuit involved in the embodiments of the present invention may be built in any wired headset, and the wired headset is used in conjunction with the smart terminal. Especially the intelligent terminal with 3.5mm audio output interface. For example: mobile phones, tablets, laptops, computers, MP3 and MP4. The embodiment of the present invention is exemplarily illustrated in the scenario in which the control device is built in the wired earphone, and the wired earphone and the mobile phone are used together. However, the embodiment of the present invention is not limited thereto.

Figure 14 is a diagram showing an example of a circuit design of an earphone according to an embodiment of the present invention. FIG. 15 is a diagram showing an example of the first voltage detection control circuit 705 of FIG. FIG. 16 is another exemplary diagram of the first voltage detection control circuit 705 of FIG. Figure 17 is a diagram showing an example of another circuit design of the earphone of the embodiment of the present invention. The above various circuits and modules are exemplarily described below in conjunction with a specific circuit design.

The specific circuit structure of the backflow detection control circuit 702 shown in FIG. 11 is as follows:

In one example, as shown in FIG. 14, the backflow detection control circuit 702 can include a resistor 813, a resistor 814, a resistor 819, a resistor 815, a switch 817, a diode 818, a comparator 820, and a NOT gate 816. Specifically, taking the terminal device as the mobile phone as an example, when the current flows from the microphone end of the mobile phone to the subsequent circuit (such as the capacitor 821 and the capacitor 822), the voltage of the reverse terminal of the comparator 820 is higher than the voltage of the non-inverting terminal, and the comparator 820 The output is low, and after the NOT gate 816, the control switch 817 is closed. Here, diode 818 provides a path for current flow. When current flows from the rear end to the microphone end of the handset, the voltage at the non-inverting terminal of the comparator 820 is higher than the inverting terminal, the comparator 820 outputs a high level, and the non-gate 816 controls the switch 817 to open. At this moment, the diode 818 is in an inverted state, which prevents loss of charge in the energy storage module. In other words, when the button 802 is pressed, the voltage on the microphone terminal of the earphone becomes low, and the electric charge flows from the storage capacitor 822 to the ground through the resistor 823, the switch 817, the resistor 814, the LDO 804, the resistor 801, and the button 802. Current flowing through resistor 814 causes the non-inverting terminal voltage of comparator 820 to be higher than the inverting terminal voltage. The comparator 820 outputs a high level and the switch 817 is turned off. Since the feedback resistor 815 is present, when the comparator 820 is output to a high level voltage, it can be ensured that the in-phase terminal voltage of the comparator is always greater than the reverse terminal voltage, and the switch 817 is always in the off state.

In another example, as shown in FIG. 17, the backflow detection control circuit 702 can include: a MOS transistor 917, a comparator 920, and a resistor 919; the microphone terminal is connected to the energy storage circuit 704 through the MOS transistor 917; The negative input terminal of the 920 is connected to the microphone end of the earphone. The positive input end of the comparator 920 is connected to the energy storage circuit 704. The output end of the comparator 920 is connected to the gate of the MOS transistor 917 through the resistor 919. . Further, in order to improve the performance of the flow detection control circuit 702, that is, to improve the blocking effect of the charge in the energy storage circuit to the power supply terminal of the terminal device, the reverse current detection control circuit 702 may further include: a MOS transistor 916 and a resistor 918; The drain of the MOS transistor 917 is connected to the drain of the MOS transistor 916; the comparator 920 is connected to the gate of the MOS transistor 916 through the resistor 918. Further, in order to improve the performance of the flow detection control circuit 702, the reverse current detection control circuit 702 may further include: a third resistor (not shown); the MOS transistor 917 is connected to the MOS transistor 916 through the third resistor. . In actual operation, when the voltage of the microphone terminal of the earphone is higher than the voltage of the capacitor 923, the output of the comparator 920 is low, the MOS transistor 916 and the MOS transistor 917 are turned on, and the current flows from the microphone end of the earphone to the capacitor 923 and the capacitor 924. . When the output voltage of the microphone terminal of the earphone is lower than the voltage of the capacitor 923, the comparator 920 outputs a high level. The MOS transistor 917 and the MOS transistor 916 are turned off to prevent charge from being lost from the capacitor 923 and the capacitor 924 to the microphone end of the earphone. Further, in order to increase the voltage difference between the non-inverting terminal and the inverting terminal of the first comparator 920, a resistor may be connected in series between the MOS transistor 917 and the MOS transistor 916 to allow current flowing through the MOS transistor 917 and the MOS transistor 916 to also Flow through the resistor.

The specific circuit structure of the signal isolation circuit 703 shown in FIG. 11 is as follows:

In one example, as shown in FIG. 14, the signal isolation circuit 703 may include a resistor 814, a resistor 823, a capacitor 821, and a capacitor 822; the sound pickup circuit 709 is connected to one end of the resistor 814, and the other end of the resistor 814 Connected to ground through the capacitor 821, the other end of the resistor 814 is also connected to one end of the capacitor 822 through the resistor 823, and the other end of the capacitor 822 is grounded. Wherein, the resistor 814 and the capacitor 821 isolate the sound signal output by the microphone (MIC) 806, prevent the sound signal outputted by the MIC 806 from being excessively attenuated and interfere with the operation of the subsequent stage circuit; the resistor 823, the capacitor 821 and the capacitor 822 are used for filtering the system. The work generates power supply noise that interferes with the pre-stage circuit. In a possible implementation, the capacitor 821 and/or the capacitor 822 may constitute an energy storage circuit 704 of the earphone for storing a weak current to the microphone end of the earphone and supplying power to other circuits or modules.

In still another example, as shown in FIG. 17, the signal isolation circuit 703 may include a low dropout linear regulator (LDO) 921, a resistor 922, a capacitor 923, and a capacitor 924; the mic end is connected to the voltage control circuit 701 to An output end of the backflow detection control circuit 702 is connected to an end of the LDO 921. The other end of the LDO 921 is connected to the ground through the capacitor 923. The other end of the LDO 921 also passes through the resistor 922. Connected to one end of the capacitor 924, the other end of the capacitor 924 is grounded. In particular, the LDO 921 can be used to prevent signal attenuation of the MIC 909 output. The principle is as follows, assuming that the LDO 921 output voltage is low (such as 2V), when the input power of the LDO 921 is higher than 2V, even if the input power supply fluctuates, it will not affect the output. In one possible implementation, the capacitor 923 and/or the capacitor 924 may constitute the energy storage circuit 704 of the earphone.

The specific circuit structure of the sound pickup circuit 709 shown in FIG. 11 is as follows:

As an example, as shown in FIG. 14, the sound pickup circuit 709 may include a capacitor 805, a microphone 806, a capacitor 807, a resistor 808, a switch 809, and a non-circuit 810; the microphone end of the earphone is connected to one end of the capacitor 805. The other end of the capacitor 805 is connected to one end of the capacitor 807 through the microphone 806. One end of the capacitor 807 is connected to one end of the switch 809 through the resistor 808, and the other end of the switch 809 is connected to the microphone end of the earphone. The other end of the 807 is grounded; the signal processing circuit 710 of the earphone is used to control the on or off of the switch 809. In other words, the sound pickup circuit 709 can be composed of a capacitor 805, a microphone 806, a capacitor 807, a resistor 808, a switch 809, and a non-circuit 810. In this embodiment, the signal processing circuit 710 can be an MCU 933. The power supply circuit 709 is powered by the MCU 933 through the control switch 809. The microphone 806 converts the sound into an electrical signal that is transmitted through the capacitor 805 to the power supply terminal of the handset microphone.

The specific circuit structure of the second voltage detection control circuit 708 shown in FIG. 11 is as follows:

As an example, as shown in FIG. 14 , the second voltage detection control circuit may include: a resistor 811 and a resistor 812. The signal processing circuit 710 is an example of the MCU 833. The microphone end of the earphone is connected to the microphone 811 through the resistor 811. One end of the resistor 812, the microphone end of the earphone is connected to the signal processing circuit 710 through the resistor 811, and the other end of the resistor 812 is grounded. In this embodiment, the voltage division value can be obtained by dividing the resistor 811 and the resistor 812, and the voltage division value is input to the MCU 833, and the analog-to-digital converter (Minus-to-Digital Converter) in the MCU 833 can be used. , ADC) and other module detection, in this MCU 833 can provide signal processing.

Further, the connection relationship between the signal processing circuit 710 and the first voltage detection control circuit 705 shown in FIG. As an example, as shown in FIG. 14, the signal processing circuit 710 is an example of an MCU 833. The output of the first voltage detection control circuit 824 is connected to a first input end of the OR circuit 825. The first voltage detection is performed. The control circuit 824 is configured to generate and transmit first information to the OR circuit 825, the first information being used to indicate an energy storage condition of the energy storage circuit 703. The microphone end of the earphone is connected to one end of the MCU 833 through the second voltage detecting control circuit (not shown), and the other end of the second voltage detecting control circuit is connected to the second input end of the OR circuit 825. The MCU 833 is used by the MCU 833. A second signal is generated and sent to the OR circuit 825, the second signal being used to indicate whether the signal processing circuit is powered. In actual work, since or circuit 825 is a dual input or gate, the characteristics of the OR gate have a high output or high. Therefore, when the first voltage detection control circuit 824 detects that the voltage of the tank circuit 703 reaches the threshold voltage, the first voltage detection control circuit 824 outputs a high level, and the OR circuit 825 also outputs a high level. In addition, when the MCU 833 is powered, the MCU 833 outputs a high level to the OR circuit 825, and the OR circuit 825 also outputs a high level, so that when the first voltage detection control circuit 824 outputs a low level, The output of the circuit 825 is guaranteed to be high, preventing accidents such as the MCU 833 and frequent power failures. At the same time, the first voltage detection control circuit 824 can also send the energy storage status information of the energy storage circuit to the MCU 833. Optionally, when the first voltage detection control circuit 824 outputs a low level, the storage circuit voltage can be represented. Insufficient, and the MCU 833 can perform corresponding operations to reduce overall power consumption.

It should be noted that the first voltage detection control circuit 824 shown in FIG. 14 may be configured with a hysteresis voltage detecting function. For example, the output is high when the voltage on the tank circuit 704 reaches 2V until the voltage of the tank circuit 704 drops to 1.85V and its output is low. In actual operation, when the first voltage detection control circuit 824 outputs a high level, the OR circuit 825 also outputs a high level, thereby closing the switch 826 to supply power to the MCU 833, and the output pin of the MCU 833 can be connected to The other input of the OR circuit 825, that is, the MCU 833 is powered up and outputs a high level to the input of the circuit 825, which can also be used to maintain normal power supply to the MCU 833, whereby the first voltage detection control circuit 824 and the MCU are provided. Any output of 833 is high to ensure that the MCU 833 has power. Further, the MCU 833 can control the power supply of the biometric detection module 830 by controlling the turning on or off of the switch 828, and the MCU 833 can also be used to calculate the current biometric value of the user (such as the heart rate value) and pass the LED 832. display. When the MCU 833 calculates the value of the biometric, if the system power consumption is too large, the voltage on the storage capacitor 822 is lower than 1.85V, the first voltage detection control circuit 824 outputs a low level, and the MCU 833 obtains the signal. Corresponding measures (such as stopping heart rate acquisition and calculation, MCU 833 enters sleep mode) will reduce system power consumption.

The specific circuit structure of the first voltage detection control circuit 705 shown in FIG. 11 is as follows:

As an example, as shown in FIG. 15, the first voltage detection control circuit 824 may include: a resistor 401, a resistor 402, a resistor 403, a comparator 404, a comparator 405, and a flip-flop 406; one end of the resistor 401 and the memory The other end of the resistor 401 is connected to one end of the resistor 403, the other end of the resistor 403 is grounded, and the other end of the resistor 401 is connected to the negative input terminal of the comparator 404. One end of the 402 is connected to the positive input of the comparator 405, the positive input of the comparator 404 and the negative input of the comparator 405 receive a reference voltage, the output of the comparator 404 and the R input of the flip flop 406 Connected to the terminal, the output of the comparator 405 is coupled to the S input of the flip flop 406. In other words, the resistor 401, the resistor 402 and the resistor 403 are connected in series, the resistor 401 is connected to the measured voltage, the resistor 403 is connected to the ground, and the voltage to be measured (Vi) is divided; the non-inverting input terminal of the comparator 404 is connected to the reference voltage, and is reversed. The input terminates the intersection of resistor 401 and resistor 402, and the output of comparator 404 is coupled to the R terminal of flip-flop 406. The non-inverting input of the comparator 405 is connected to the intersection of the resistor 401 and the resistor 402, the inverting input of the comparator 405 is connected to the reference voltage, the output is connected to the S terminal of the flip-flop 406, and the Q of the flip-flop 406 is used as the voltage detection. signal of.

Output state equation according to flip-flop 406

It can be seen that when the voltage of the measured voltage (Vi) is too low, the voltage of the inverting input terminal of the comparator 404 is lower than the reference voltage. At this time, the comparator 404 outputs a high level, and the comparator 405 outputs a low level, and the Q terminal of the flip-flop 406 outputs a low level. When the Vi voltage is gradually increased, the voltage of the inverting input terminal of the comparator 404 is higher than the reference voltage, but the voltage of the non-inverting input terminal of the comparator 405 is lower than the reference voltage. At this time, the output of the comparator 404 is a low level, the comparator When the output of 405 is low, the Q terminal of flip-flop 406 outputs a low level. When the Vi voltage rises again, so that the voltage of the inverting input terminal of the comparator 404 is higher than the reference voltage, the non-inverting input terminal of the comparator 405 is higher than the reference voltage, the comparator 404 outputs a low level, and the output of the comparator 405 is high. At the level, the Q terminal of the flip flop 406 outputs a high level. If the measured voltage is reduced to the opposite input voltage of comparator 404 at this time, the voltage at the non-inverting input of comparator 405 is less than the reference voltage. At this time, the comparator 404 outputs a low level, and the comparator 405 outputs a low level, but the previous state of the Q terminal of the flip-flop 406 is a high level, so the current state of the Q terminal of the flip-flop 406 is also a high level. . The measured voltage continues to decrease, as low as the voltage at the inverting input of the comparator 404 is less than the reference voltage, the voltage at the non-inverting input of the comparator 405 is less than the reference voltage, the output of the comparator 404 is high, and the output of the comparator 405 is low. level. The Q terminal output of the current flip flop 406 is at a low level. Thereby, the detection of the hysteresis voltage can be achieved. In this embodiment, the detection range of the hysteresis voltage can also be adjusted by adjusting the ratio of the resistor 401, the resistor 402, and the resistor 403.

As still another example, as shown in FIG. 16 , the first voltage detection control circuit 824 may include a resistor 407 , a resistor 409 , a resistor 408 , and a comparator 411 . The tank circuit 704 is connected to the resistor 409 through the resistor 407 . At one end, the other end of the resistor 409 is coupled to the output of the comparator 411, the negative input of the comparator 411 receives a reference voltage, and the positive input of the comparator 411 is coupled to ground through the resistor 408. In other words, the resistor 407 is connected to the measured voltage and the non-inverting input of the comparator 411. The resistor 409 is connected to the output of the comparator 411 and the non-inverting input. The resistor 408 is connected to the non-inverting input of the comparator 411 and the ground. The inverting input is connected to the reference voltage. In actual operation, when the measured voltage is sufficiently low that the voltage at the non-inverting input of the comparator 411 is less than the reference voltage, the comparator 411 outputs a low level. When the measured voltage rises, the non-inverting input voltage of the comparator 411 is the total resistance of the resistor 408 in parallel with the resistor 409 and the partial pressure of the resistor 407. When the voltage rises to a voltage at the non-inverting input of the comparator 411 that is higher than the reference voltage, the output of the comparator 411 is at a high level, which is equivalent to changing the calculation model of the voltage at the non-inverting input of the comparator 411. When the voltage drops by a certain value such that the voltage of the non-inverting input terminal of the comparator 411 is lower than the reference voltage value, the comparator 411 outputs the low level again. It can be found that the comparator 411 is high from the output to the low output, and the comparator 411 outputs a low level to the output high level, and the voltage calculation model of the non-inverting input terminal is different, so the voltage thresholds of the two are different. In other words, the comparator 411 outputs a threshold value from a low level to a high level greater than a threshold value from a high level to a low level, so that the first voltage detection control circuit 705 realizes hysteresis voltage detection.

The specific circuit structure of the power take-off circuit 707 shown in FIG. 11 is as follows:

As an example, as shown in FIG. 14, the power take-off circuit 707 may include a switch 803 through which the microphone end is connected to ground. Taking the terminal device as the mobile phone as an example, when the mobile phone system does not use the microphone, the microphone end of the mobile phone sleeps, which is reflected that the output voltage of the microphone end of the mobile phone becomes lower, and the power supply capability becomes weak. The output voltage of the microphone terminal of the mobile phone becomes lower (below the voltage of the storage capacitor 822), so that the electric charge flows from the storage capacitor 822 back to the microphone end of the mobile phone. At this point, the comparator 820 outputs a high level, which in turn controls the switch 817 to open. Meanwhile, taking the signal processing circuit 710 as an example for the MCU 833, the MCU 833 detects that the microphone end of the mobile phone is in a sleep state through the second voltage detection control circuit (the resistor 811 and the resistor 812), and triggers the mobile phone output through the control switch 803. high voltage. Optionally, the trigger mode may be to lower the voltage of the microphone end of the mobile phone by 25 ms after the microphone end of the mobile phone sleeps for 40 ms.

The specific electrical structure of the voltage protection circuit 701 shown in FIG. 11 is as follows:

As an example, as shown in FIG. 14, the voltage protection circuit can be a low dropout linear regulator (LDO) 804. In other words, taking the terminal device as the mobile phone as an example, when the earphone is connected to the mobile phone through the 3.5mm interface, the mobile phone will output a high voltage, and the LDO 804 can prevent the rear-end circuit from being damaged when the mobile phone outputs 5V voltage.

As another example, as shown in FIG. 17, the voltage protection circuit 701 may include a metal oxide semiconductor (MOS) transistor 903, a comparator 907, and a resistor 906; the microphone terminal is connected to the MOS transistor 903; the comparator 907 The negative input receives the threshold voltage, the positive input of the comparator 907 is coupled to the microphone terminal of the earphone, and the output of the comparator 907 is coupled to the gate of the MOS transistor 903 via the resistor 906. Further, as shown in FIG. 17, the voltage protection circuit further includes: a MOS transistor 904 and a resistor 905; a drain of the MOS transistor 904 is connected to a drain of the MOS transistor 903; an output of the comparator 907 passes through the resistor 905 is connected to the gate of the MOS transistor 903. Specifically, taking the terminal device as the mobile phone as an example, when the voltage on the microphone end of the earphone is higher than the threshold voltage (Vref), the comparator 907 outputs a high level, and the MOS transistor 903 and the MOS transistor 904 are turned off, when the microphone of the earphone When the voltage on the terminal is lower than Vref, the comparator 907 outputs a low level, and the MOS transistor 903 and the fourth MOS transistor are turned on. More specifically, it is assumed that the Vref is set to 2.8V. When the output voltage of the microphone terminal of the mobile phone is higher than 2.8V, the MOS transistor 903 and the MOS transistor 904 are turned off to prevent the excessive voltage from damaging the subsequent circuit. When the voltage of the mobile phone microphone power supply terminal is lower than 2.8V, the MOS transistor 903 and the MOS transistor 904 are turned on to supply the circuit charge of the subsequent stage.

As shown in FIG. 14 , the signal processing circuit 710 is taken as an example for the MCU 833. The energy storage circuit 704 of the earphone can also be connected to the biometric detection module 830 of the earphone through a switch 828. The MCU 833 is used to control the guiding of the switch 828. Turn it on or off. In other words, the power of the biometric detection module 830 is controlled by the MCU 833. Taking the terminal device as a mobile phone as an example, when the mobile phone needs to send a command to the earphone, only a specific waveform needs to be sent on the right channel. The MCU 833 and the biometric detection module 830 will receive an instruction, by which the MCU 833 can stop the calculation and display of the biometrics, and at the same time, the biometric detection module 830 sends the data to the mobile phone through the microphone to perform on the mobile phone. Calculation and display of biometrics. Further, as shown in FIG. 14, the biometric detection module can perform bidirectional communication with the MCU 833 through an inter-integrated circuit (IIC)/serial peripheral interface (SPI). As shown in FIG. 14, as an example, the capacitor 822 in the tank circuit can also be connected to one end of a low dropout linear regulator (LDO) 827, and the other end of the LDO 827 can also be connected to ground through a capacitor 829. The other end of the LDO 827 can also be connected to the biometric detection module 830 through the switch 828. Further, the other end of the LDO 827 can also be connected to the ground through a capacitor 831, thereby increasing the performance of the circuit.

It should be understood that the connection relationship between the respective modules or circuits shown in FIG. 14 to FIG. 17 , the specific circuit structure of each module or circuit is merely exemplary description, and the circuit structure of FIG. 14 and FIG. 17 is avoided in order to avoid repetition. The same portions will not be described again (for example, the power take-off circuit and the second voltage detecting control circuit and the communication circuit).

In the embodiment of the present invention, the traditional wired earphone has the function of detecting biometrics (for example, heart rate) by adding a biometric detection module to a conventional wired earphone with a 3.5 mm audio interface. In addition, the detection result can be displayed in real time by adding a biometric display module. As an example, the biometric display module includes a plurality of light emitting diode LEDs. As shown in FIG. 11, the earphone may further include a biometric display module 712. Further, as shown in FIG. 14 , the biometric display module may indicate the value of the biometric by using a Light-Emitting Diode (LED) 832 or an Organic Light-Emitting Diode (OLED) or other visualization device. For example, heart rate intensity can be used, for example, LEDs of several different colors can be used to indicate different heart rate intensity intervals. For example, a blue LED can be used to represent a heart rate between 30 BPM and 80 BPM; wherein, the green LED represents a heart rate between 80 and 110 BPM; the red represents between 110 and 150 BPM; the yellow represents between 150 and 180 BPM; and the orange represents The heart rate range is between 180 and 220 BPM. It should be understood that the above-mentioned heart rate intensity interval and indication manner are only examples of the embodiments of the present invention, and embodiments of the present invention are not limited thereto. For example, the biometric display module 712 can display the color while indicating the heart rate with different blinking frequencies. For example, the higher the heart rate LED blinking frequency, the higher the heart rate. As another example, the biometric display module 712 can also use one LED to indicate a heart rate interval through different blinking speeds.

Since the earphone in the embodiment of the present invention does not require a battery, there is no need to charge, and it is not necessary to carry a charging cable or a charger. Moreover, it is easy to use and can be used by inserting a target device (for example, a mobile phone), thereby reducing the production cost of the earphone. Further, the earphone in the embodiment of the present invention can support the heart rate measurement on the earphone and indicate the heart rate interval, and further, by setting a storage circuit in the earphone for storing the charge from the microphone end of the earphone. In this way, even if the power supply capability of the earphone plug of the terminal device is insufficient, the energy storage circuit can normally supply power to the earphone, preventing the earphone from excessively consuming a large current, causing the power supply terminal voltage to drop excessively, thereby affecting the normal voice transmission of the earphone. Features. Further, by inserting a voltage protection circuit for the earphone, it is possible to prevent the circuit of the back end from being damaged when the voltage outputted by the power supply terminal is too large, thereby affecting the normal operation of the earphone. Further, by integrating a signal isolation circuit for the earphone, the earphone performs biometric detection and listening to music, and the use of the microphone does not affect each other. Furthermore, by incorporating a countercurrent detection control circuit for the earphone, it is possible to prevent the loss of the charge of the earphone storage circuit due to a sudden drop in the output voltage of the mobile phone, thereby preventing the earphone from suddenly powering down. Further, by providing a power supply voltage control circuit for the earphone, the power supply voltage of the signal processing module can be controlled in real time.

Those of ordinary skill in the art will appreciate that the elements and circuits of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods to implement the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present application. In the several embodiments provided herein, it should be understood that the disclosed circuits, branches, and units may be implemented in other manners. For example, the branch described above is schematic. For example, the division of the unit is only a logical function division, and the actual implementation may have another division manner, for example, multiple units or components may be combined or may be integrated into A branch, or some features can be ignored, or not executed. The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application, which is essential or contributes to the prior art, or a part of the technical solution, may be embodied in the form of a software product, which is stored in a storage medium, including The instructions are used to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like. .

The foregoing is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application. It should be covered by the scope of protection of this application. Therefore, the scope of protection of this application is subject to the scope of protection of the claims.

Claims

A control device for an earphone, comprising:

Voltage protection circuit

When the earphone is inserted into the terminal device, the voltage protection circuit is connected to the power supply end of the terminal device through the microphone end of the earphone, and the voltage protection circuit is configured to receive the voltage output by the power supply terminal through the microphone end And outputting a first voltage, wherein the voltage output by the power supply terminal is greater than or equal to the first voltage.
The control device according to claim 1, wherein when the voltage outputted by the power supply terminal is higher than a threshold voltage, the first voltage is equal to the threshold voltage, and the voltage output by the power supply terminal is lower than the threshold value. At voltage, the first voltage is equal to the voltage output by the power supply terminal.
The control device according to claim 1 or 2, wherein the control device further comprises:

Countercurrent detection control circuit;

The microphone end of the earphone is connected to the energy storage circuit of the earphone through the backflow detection control circuit, and the reverse current detection control circuit is configured to compare the voltage in the energy storage circuit with the voltage of the microphone end, and compare according to The result controls the electrical or electrical disconnection between the tank circuit and the mic end.
The control device according to claim 3, wherein the backflow detection control circuit comprises:

a first MOS transistor, a first comparator, and a first resistor;

The mic end is connected to the energy storage circuit through the first MOS tube;

a negative input end of the first comparator is connected to a microphone end of the earphone, a positive input end of the first comparator is connected to the energy storage circuit, and an output end of the first comparator passes the A resistor is coupled to the gate of the first MOS transistor.
The control device according to claim 4, wherein the reverse current detection control circuit further comprises:

a second MOS transistor and a second resistor;

a drain of the first MOS transistor is connected to a drain of the second MOS transistor, and a source of the second MOS transistor is connected to the energy storage circuit;

An output of the first comparator is coupled to a gate of the second MOS transistor through the second resistor.
The control device according to claim 5, wherein the reverse current detection control circuit further comprises:

Third resistance;

The first MOS transistor is connected to the second MOS transistor through the third resistor.
The control device according to any one of claims 1 to 6, wherein the control device further comprises:

a signal isolation circuit, the microphone end of the earphone is connected to one end of the signal isolation circuit through a sound pickup circuit of the earphone, the sound pickup circuit is configured to convert the received sound signal into an electrical signal; Interference between the electrical signal and a circuit connected to the other end of the signal isolation circuit.
The control device according to claim 7, wherein said signal isolation circuit comprises:

a current limiting component, a fifth resistor, a first capacitor, and a second capacitor;

The sound pickup circuit is connected to one end of the current limiting element, the other end of the current limiting element is connected to the ground through the first capacitor, and the other end of the current limiting element is further connected to the fifth resistor through the fifth resistor One end of the second capacitor, and the other end of the second capacitor is grounded;

Wherein, the current limiting component is a fourth resistor or a first low dropout linear regulator LDO.
The control device according to claim 7 or 8, wherein the sound pickup circuit comprises:

a third capacitor, a microphone, a fourth capacitor, a sixth resistor, a first switch, and a non-circuit;

The microphone end of the earphone is connected to one end of the third capacitor, and the other end of the third capacitor is connected to one end of the fourth capacitor through the microphone, and one end of the fourth capacitor passes the sixth A resistor is coupled to one end of the first switch, the other end of the first switch is coupled to the mic end, and the other end of the fourth capacitor is coupled to ground.
The control device according to any one of claims 1 to 9, wherein the control device further comprises:

a supply voltage control circuit for controlling a supply voltage of the signal processing circuit of the earphone;

The power supply voltage control circuit includes:

a first voltage detection control circuit, or a circuit and a second switch;

An output of the first voltage detection control circuit is coupled to a first input of the OR circuit, the first voltage detection control circuit is configured to generate and transmit a first signal to the OR circuit;

An output of the signal processing circuit is coupled to a second input of the OR circuit, the signal processing circuit for generating and transmitting a second signal to the OR circuit;

The energy storage circuit is connected to the signal processing circuit through the second switch;

The OR circuit is configured to receive the first signal and the second signal, and control whether the second switch is turned on or off according to the first signal and/or the second signal.
The control device according to claim 10, wherein said first voltage detection control circuit comprises:

a seventh resistor, an eighth resistor, a ninth resistor, a second comparator, a third comparator, and a trigger;

One end of the seventh resistor is connected to the energy storage circuit, the other end of the seventh resistor is connected to one end of the ninth resistor through the eighth resistor, and the other end of the ninth resistor is grounded. The other end of the seventh resistor is connected to the negative input terminal of the second comparator, one end of the eighth resistor is connected to the positive input terminal of the third comparator, and the positive input terminal of the second comparator And a negative input terminal of the third comparator receives a reference voltage, an output of the second comparator is coupled to an R input of the flip-flop, an output of the third comparator and the flip-flop S input is connected;

Alternatively, the first voltage detection control circuit comprises:

a tenth resistor, an eleventh resistor, a twelfth resistor, and a fourth comparator;

The energy storage circuit is connected to one end of the eleventh resistor through the tenth resistor, and the other end of the eleventh resistor is connected to an output end of the fourth comparator, the fourth comparator A negative input receives a reference voltage, and a positive input of the fourth comparator is coupled to ground through the twelfth resistor.
The control device according to any one of claims 1 to 11, wherein the control device further comprises:

Take power circuit

The microphone end of the earphone is connected to the signal processing circuit of the earphone through the power take-off circuit, and the signal processing circuit is configured to control the power take-off circuit to generate and send a third signal to the terminal device inserted by the earphone, The third signal is used to stimulate the terminal device to increase an output voltage of a power supply end of the terminal device.
The control device according to claim 12, wherein the power take-off circuit comprises:

Third switch

The mic end is connected to ground through the third switch.
The control device according to any one of claims 1 to 13, wherein the control device further comprises:

a second voltage detection control circuit;

The microphone end of the earphone is connected to an input end of a signal processing circuit of the earphone by the second voltage detection control circuit, and the second voltage detection control circuit is configured to generate and send a fourth signal to the signal processing circuit The fourth signal is used to indicate a voltage condition of the microphone terminal.
The control device according to claim 14, wherein said second voltage detection control circuit comprises:

The thirteenth resistor and the fourteenth resistor;

a microphone end of the earphone is connected to one end of the fourteenth resistor through the thirteenth resistor, and a microphone end of the earphone is connected to the signal processing circuit through the thirteenth resistor, the fourteenth The other end of the resistor is grounded.
The control device according to any one of claims 1 to 15, wherein the control device further comprises:

Fourth switch

The energy storage circuit of the earphone is connected to the biometric detection module of the earphone through a fourth switch, and the signal processing circuit of the earphone is used to control the fourth switch to be turned on or off.
The control device according to claim 16, wherein the control device further comprises:

a second low dropout linear regulator LDO;

The energy storage circuit is connected to one end of the second LDO, the other end of the second LDO is connected to the ground through a fifth capacitor, and the other end of the second LDO is further connected to the biometric by the fourth switch Detection module.
The control device according to claim 17, wherein the control device further comprises:

Sixth capacitor

The other end of the second LDO is connected to ground through a sixth capacitor.
The control device according to any one of claims 1 to 18, wherein the voltage protection circuit is a third low dropout linear regulator LDO.
The control device according to any one of claims 1 to 18, wherein the voltage protection circuit comprises:

a third metal oxide semiconductor MOS transistor, a fifth comparator, and a fifteenth resistor;

The mic end is connected to the third MOS tube;

a negative input terminal of the fifth comparator receives a threshold voltage, a positive input terminal of the fifth comparator is connected to the microphone end, and an output end of the fifth comparator is connected to the fifth through the fifteenth resistor The gate of the third MOS transistor.
The control device according to claim 20, wherein the voltage protection circuit further comprises:

a fourth MOS transistor and a sixteenth resistor;

a drain of the fourth MOS transistor is connected to a drain of the third MOS transistor;

An output of the fifth comparator is connected to a gate of the third MOS transistor through the sixteenth resistor.
A wired earphone, comprising:

The control device according to any one of claims 1 to 21.
The wired earphone according to claim 22, wherein said control means is disposed in a wire control panel of said wired earphone.
The wired headset according to claim 22 or 23, wherein the wired headset further comprises:

Biometric display module;

The signal processing circuit of the earphone is connected to the biometric display module, and the biometric display module is configured to display a detection result of the biometric detection module of the earphone.