CN115022775B

CN115022775B - Driving circuit, terminal equipment and protection method

Info

Publication number: CN115022775B
Application number: CN202210933853.5A
Authority: CN
Inventors: 黄停
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2022-08-04
Filing date: 2022-08-04
Publication date: 2023-07-07
Anticipated expiration: 2042-08-04
Also published as: CN115022775A

Abstract

The embodiment of the application provides a driving circuit, terminal equipment and a protection method of a loudspeaker, which relate to the technical field of circuits, and can reduce cost and occupied space. The driving circuit comprises a loudspeaker, a coder and a motor driving module; the motor driving module is respectively and electrically connected with the loudspeaker and the encoder; the coder is used for outputting the sound source to the motor driving module; the motor driving module is used for amplifying the sound source and outputting the amplified sound source to the loudspeaker so as to drive the loudspeaker to operate.

Description

Driving circuit, terminal equipment and protection method

Technical Field

The present disclosure relates to the field of circuit technologies, and in particular, to a driving circuit, a terminal device, and a protection method.

Background

The speaker is one of the basic configurations of the terminal device. In order to pursue better sound quality and louder sound, a separate high-efficiency intelligent power amplifier (Smart Power Amplifier, smart PA) module is generally required to drive the loudspeaker to work. However, since the Smart PA has a high cost, it causes a high cost of the terminal device.

Disclosure of Invention

In order to solve the technical problems, the application provides a driving circuit, a terminal device and a protection method. The cost of the terminal equipment can be reduced, and the occupied space is reduced.

In a first aspect, embodiments of the present application provide a driving circuit including a speaker, a codec, and a motor driving module; the motor driving module is respectively and electrically connected with the loudspeaker and the encoder; the coder is used for outputting the sound source to the motor driving module; the motor driving module is used for amplifying the sound source and outputting the amplified sound source to the loudspeaker so as to drive the loudspeaker to operate.

The loudspeaker can be driven to work through the motor driving module without independently setting the intelligent power amplification module, so that one intelligent power amplification module can be saved, the cost of the terminal equipment can be reduced, the occupation ratio of the internal space of the terminal equipment is reduced, and the utilization rate of the internal space of the terminal equipment is improved.

In some possible implementations, the driving circuit further includes a processing module electrically connected to the encoder; the coder comprises a first analog-to-digital converter and a second analog-to-digital converter, wherein the first analog-to-digital converter is used for collecting the voltage of the positive end of the loudspeaker and sending the voltage to the processing module, and the second analog-to-digital converter is used for collecting the voltage of the negative end of the loudspeaker and sending the voltage to the processing module; the processing module is used for determining the current temperature of the voice coil of the loudspeaker according to the voltage of the positive end of the loudspeaker and the voltage of the negative end of the loudspeaker, comparing the current temperature with the corresponding relation between the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the current temperature so as to control the codec to output the power of the sound source at the current temperature.

Since a plurality of analog-to-digital converters are usually integrated inside the codec, and the number of analog-to-digital converters integrated inside the codec is larger than the number of analog-to-digital converters actually used, i.e. there are redundant analog-to-digital converters inside the codec. Therefore, the voltage at two ends of the loudspeaker can be acquired by using the redundant analog-to-digital converter in the coder, so that the temperature of the voice coil of the loudspeaker can be determined on the basis of not increasing the structure, and the cost of the voice coil of the loudspeaker can not be additionally increased due to the monitoring of the temperature of the voice coil of the loudspeaker on the basis of reducing the cost of terminal equipment by adopting the motor driving module.

The voltages at the positive and negative terminals of the speaker are, for example, the voltages at the voice coil of the speaker.

In some possible implementations, the motor driving module is electrically connected with the processing module on the basis that the codec includes a first analog-to-digital converter and a second analog-to-digital converter; the motor driving module is also used for collecting the current output to the loudspeaker and sending the current to the processing module; the processing module is used for determining the current temperature of the voice coil of the loudspeaker according to the voltage of the positive end of the loudspeaker, the voltage and the current of the negative end of the loudspeaker, comparing the current temperature with the corresponding relation between the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the current temperature so as to control the codec to output the power of the sound source at the current temperature. The output current is collected through the structure of collecting current arranged in the motor driving module, so that the impedance of the voice coil is determined according to the voltage at two ends of the voice coil and the current flowing through the voice coil, and the temperature of the voice coil is determined according to the impedance of the voice coil.

In some possible implementations, on the basis that the codec includes a first analog-to-digital converter and a second analog-to-digital converter, the driving circuit further includes a sampling resistor, a first end of the sampling resistor is electrically connected to the motor driving module, and a second end of the sampling resistor is electrically connected to a negative terminal of the speaker; the coder and decoder also comprises a third analog-to-digital converter, and the third analog-to-digital converter is used for collecting the voltage of the first end of the sampling resistor and sending the voltage to the processing module; the processing module is used for determining the voltage difference between two ends of the sampling resistor according to the voltage of the first end of the sampling resistor and the voltage of the negative end of the loudspeaker, determining the current of the loudspeaker according to the voltage difference and the resistance value of the sampling resistor, determining the current temperature of the voice coil according to the voltage of the positive end of the loudspeaker, the voltage and the current of the negative end of the loudspeaker, comparing the current temperature with the corresponding relation between the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the current temperature so as to control the codec to output the power of the sound source at the current temperature. That is, by setting a sampling resistor connected in series with the voice coil, the current of the voice coil is determined based on the voltage across the sampling resistor and the resistance value of the sampling resistor, the impedance of the voice coil is determined based on the voltage across the voice coil and the current flowing through the voice coil, and the temperature is determined based on the impedance.

Since a plurality of analog-to-digital converters are usually integrated inside the codec, and the number of analog-to-digital converters integrated inside the codec is larger than the number of analog-to-digital converters actually used, i.e. there are redundant analog-to-digital converters inside the codec. Therefore, the voltage of the sampling resistor can be acquired by using the redundant analog-to-digital converter in the coder, so that the acquisition of the temperature of the voice coil of the loudspeaker is realized on the basis of not increasing the structure, and the additional cost is not increased due to the monitoring of the temperature of the voice coil of the loudspeaker on the basis of reducing the cost of terminal equipment by adopting the motor driving module.

The resistance of the sampling resistor is, for example, between 50 and 400 milliohms. For example, 50 milliohms, 60 milliohms, 70 milliohms, 80 milliohms, 90 milliohms, 100 milliohms, 150 milliohms, 200 milliohms, 300 milliohms, 400 milliohms, etc., i.e., the resistance of the sampling resistor is low, so that a large loss can be avoided while determining the temperature of the voice coil.

In some possible implementations, on the basis that the codec includes the first analog-to-digital converter and the second analog-to-digital converter, the driving circuit further includes a first filtering voltage reduction module and a second filtering voltage reduction module, where the first filtering voltage reduction module is located between the first analog-to-digital converter and the positive end of the speaker and is used for filtering and reducing the voltage of the positive end of the speaker and outputting the voltage to the first analog-to-digital converter, and the second filtering voltage reduction module is located between the second analog-to-digital converter and the negative end of the speaker and is used for filtering and reducing the voltage of the negative end of the speaker and outputting the voltage to the second analog-to-digital converter, so as to avoid damage to the codec caused by larger voltage.

In some possible implementations, on the basis that the driving circuit further includes a first filtering step-down module and a second filtering step-down module, the first filtering step-down module and the second filtering step-down module each include a blocking capacitor, a first resistor and a second resistor, a first pole of the blocking capacitor of the first filtering step-down module is electrically connected with a positive end of the speaker, a second pole of the blocking capacitor is electrically connected with a first end of the first resistor, a second end of the first resistor and a first end of the second resistor are electrically connected with the first analog-to-digital converter, and a second end of the second resistor is grounded; the first pole of the blocking capacitor of the second filtering voltage reduction module is electrically connected with the negative end of the loudspeaker, the second pole of the blocking capacitor is electrically connected with the first end of the first resistor, the second end of the first resistor and the first end of the second resistor are electrically connected with the second analog-to-digital converter, and the second end of the second resistor is grounded. The filtering voltage reduction module has simple structure and lower cost.

It should be noted that, the foregoing description is only given by taking the first filtering step-down module and the second filtering step-down module including the blocking capacitor, the first resistor and the second resistor as examples, but the description does not limit the application, and the effects of reducing the voltage are all within the protection scope of the application.

The resistance values of the first resistor and the second resistor and the blocking capacitor are not limited, and may be selected by those skilled in the art according to practical situations.

In some possible implementations, on the basis that the driving circuit includes the sampling resistor, the driving circuit further includes a third filtering step-down module, located between the first end of the sampling resistor and the third analog-to-digital converter, configured to filter and step down the voltage at the first end of the sampling resistor, and output the voltage to the third analog-to-digital converter, so as to avoid damage to the encoder when the voltage at the first end of the sampling resistor is greater.

In some possible implementations, on the basis that the driving circuit further includes a third filter buck module, the third filter buck module also includes a first resistor, a second resistor, and a blocking capacitor, a first pole of the blocking capacitor of the third filter buck module is electrically connected to the first end of the sampling resistor, a second pole of the blocking capacitor is electrically connected to the first end of the first resistor, a second end of the first resistor and a first end of the second resistor are electrically connected to the third analog-to-digital converter, and a second end of the second resistor is grounded.

It should be noted that, the above description is given by taking the third filtering step-down module including the dc blocking capacitor, the first resistor and the second resistor as examples, but the present application is not limited thereto, and the step-down function is within the protection scope of the present application.

In some possible implementations, the driving circuit includes a processing module, where the processing module includes a module such as a digital signal processor that can perform data processing.

In a second aspect, embodiments of the present application further provide a terminal device, including the driving circuit in the first aspect. The technical effects corresponding to the second aspect and any implementation manner of the second aspect may be referred to the technical effects corresponding to the first aspect and any implementation manner of the first aspect, which are not described herein.

In a third aspect, an embodiment of the present application provides a method for protecting a speaker, where the method for protecting a speaker is applied to the driving circuit of the first aspect, and the method for protecting a speaker includes: respectively obtaining the voltages of the positive end and the negative end of the loudspeaker; determining the impedance of a voice coil in the loudspeaker according to the voltages of the positive end and the negative end of the loudspeaker; determining the current temperature of the voice coil according to the impedance; comparing the corresponding relation between the current temperature and the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the current temperature; and controlling the coder to output the power of the sound source at the current temperature.

The technical effects corresponding to the third aspect and any implementation manner of the third aspect may be referred to the technical effects corresponding to the first aspect and any implementation manner of the first aspect, which are not described herein.

In some possible implementations, determining the impedance of a voice coil within a speaker from the voltages at the positive and negative terminals of the speaker includes: acquiring current output by a motor driving module to a loudspeaker; the impedance of the speaker voice coil is determined from the voltage and current at the positive and negative terminals of the speaker.

In some possible implementations, the driving circuit further includes a sampling resistor, a first end of the sampling resistor is electrically connected to the motor driving module, and a second end of the sampling resistor is electrically connected to a negative terminal of the speaker; determining the impedance of a voice coil within a speaker from the voltages at the positive and negative terminals of the speaker, comprising: acquiring the voltage of a first end of a sampling resistor; determining the voltage difference between two ends of the sampling resistor according to the voltage of the first end of the sampling resistor and the voltage of the negative end of the loudspeaker; determining the current of the loudspeaker according to the voltage difference and the resistance value of the sampling resistor; and determining the impedance of the voice coil in the loudspeaker according to the voltage of the positive end of the loudspeaker, the voltage and the current of the negative end of the loudspeaker.

In some possible implementations, respectively acquiring voltages at the positive and negative terminals of the speaker includes: obtaining voltages of a positive end and a negative end of the loudspeaker after filtering and depressurization; the voltages of the positive terminal and the negative terminal of the loudspeaker are determined according to the voltages of the positive terminal and the negative terminal of the loudspeaker after the filtering step-down.

In some possible implementations, obtaining the voltage at the first end of the sampling resistor includes: acquiring the voltage of the first end of the sampling resistor after filtering and reducing the voltage; and determining the voltage of the first end of the sampling resistor according to the voltage of the first end of the sampling resistor after the filtering step-down.

In a fourth aspect, embodiments of the present application provide a computer-readable storage medium. The computer readable storage medium comprises a computer program which, when run on a terminal device, causes the terminal device to perform the third aspect and the method of protecting a loudspeaker of any of the third aspects.

Any implementation manner of the fourth aspect and any implementation manner of the fourth aspect corresponds to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the fourth aspect may be referred to the technical effects corresponding to any implementation manner of the third aspect, and are not described herein.

In a fifth aspect, embodiments of the present application provide a computer program product comprising a computer program which, when run, causes a computer to perform the method of protecting a loudspeaker as in any of the third or fourth aspects.

Any implementation manner of the fifth aspect and any implementation manner of the fifth aspect corresponds to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the fifth aspect may be referred to the technical effects corresponding to any implementation manner of the third aspect, and are not described herein.

In a sixth aspect, the present application provides a chip comprising processing circuitry, a transceiver pin. Wherein the transceiver pin and the processing circuit communicate with each other through an internal connection path, the processing circuit performing the protection method of the speaker as in any one of the third aspect or the third aspect to control the receiving pin to receive signals and the transmitting pin to transmit signals.

Any implementation manner of the sixth aspect and any implementation manner of the sixth aspect correspond to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the sixth aspect may be referred to the technical effects corresponding to any implementation manner of the third aspect, and are not described herein.

Drawings

Fig. 1 is a schematic structural diagram of a related art terminal device;

fig. 2 is a schematic structural diagram of a terminal device according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a driving circuit according to an embodiment of the present disclosure;

fig. 4 is a schematic diagram of another structure of a driving circuit according to an embodiment of the present disclosure;

fig. 5 is a schematic diagram of another structure of a driving circuit according to an embodiment of the present disclosure;

fig. 6 is a schematic diagram of another structure of a driving circuit according to an embodiment of the present disclosure;

fig. 7 is a schematic diagram of another structure of a driving circuit according to an embodiment of the present disclosure;

fig. 8 is a flowchart of a method for protecting a speaker according to an embodiment of the present application;

fig. 9 is a flowchart of a method for protecting a speaker according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

The term "and/or" is herein merely an association relationship describing an associated object, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone.

The terms first and second and the like in the description and in the claims of embodiments of the present application are used for distinguishing between different objects and not necessarily for describing a particular sequential order of objects. For example, the first target object and the second target object, etc., are used to distinguish between different target objects, and are not used to describe a particular order of target objects.

In the embodiments of the present application, words such as "exemplary" or "such as" are used to mean serving as examples, illustrations, or descriptions. Any embodiment or design described herein as "exemplary" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

In the description of the embodiments of the present application, unless otherwise indicated, the meaning of "a plurality" means two or more. For example, the plurality of processing units refers to two or more processing units; the plurality of systems means two or more systems.

In order to facilitate understanding of the embodiments of the present application, the following description will briefly explain the problems in the prior art and the procedure in which the inventor proposes the embodiments of the present application in conjunction with fig. 1. As shown in fig. 1, a motor 191 and a speaker 170A are typically included in a terminal device (e.g., a cell phone).

The speaker 170A, also called "speaker", is used to convert audio electric signals into sound signals, and the mobile phone can listen to music, or to hands-free conversation, etc. through the speaker 170A. In order to pursue better sound quality and louder sound, a separate high-efficiency intelligent power amplifier module 30 is generally required to drive the speaker 170A to operate. Specifically, a CODEC 171 demodulates and processes an input audio signal (such as music) of an application layer, and then changes the audio signal into a sound source, and sends the sound source to the intelligent power amplifier module 30, and the intelligent power amplifier module 30 lifts the sound source (for example, up to 10V), and outputs the sound source into a signal with driving capability to the speaker 170A, so as to drive the speaker 170A to operate.

The motor 191 can realize a vibration function so that a user receives tactile feedback when performing touch operation on the mobile phone and confirms the execution condition of the operation; or the mobile phone generates vibration when receiving the notification so as to remind the user. The motor 191 provided in the handpiece is typically a linear motor (e.g., an X-axis motor or a Z-axis motor, etc.) or a rotor motor. In order to realize vibration, the rotor motor generally outputs a power signal through a power management module to drive the rotor motor to vibrate. To achieve vibration, a motor drive module (also referred to as a motor boost) 172 is required to drive the linear motor. For example, the preset motor vibration waveform is changed based on the music of the application layer to generate a motor vibration waveform similar to the music rhythm and output the motor vibration waveform as a motor sound source to the motor driving module 172, and the motor driving module 172 lifts the motor sound source (e.g. to 10V) and outputs the motor sound source to the linear motor, so that the vibration rhythm of the motor is similar to the music rhythm. Of course, the vibration form of the motor is not limited thereto, and may be, for example, vibration with a fixed frequency, etc., and the specific principle may be referred to in the prior art, and will not be described herein.

However, only one motor is typically provided in a cell phone. Regardless of whether the type of motor in the handpiece is a linear motor or a rotor motor, the motor drive module 172 is integrated into the handpiece for manufacturer selection. However, if a rotor motor is used in the product instead of a linear motor, the motor drive module 172 would be wasteful.

As can be seen from the above description, the intelligent power amplifier module 30 mainly acts to raise the voltage of the sound source (e.g. to 10V), and the motor driving module 172 also acts to raise the voltage, i.e. the two functions are substantially the same.

Based on this, this embodiment of the application provides a drive circuit, including motor drive module etc. through motor drive mould drive speaker work, need not to set up intelligent power amplifier module alone to can save an intelligent power amplifier module, in this way, can reduce terminal equipment's cost, and reduce terminal equipment inner space's duty cycle, promoted terminal equipment inner space's utilization ratio. The driving circuit is applied to terminal equipment, wherein the terminal equipment provided by the embodiment of the application can be a mobile phone, a computer, a tablet personal computer, a personal digital assistant (personal digital assistant, PDA for short), a vehicle-mounted computer, a television, intelligent wearable equipment, intelligent household equipment and the like, and the specific form of the terminal equipment is not particularly limited.

Taking a mobile phone as an example, referring to fig. 2, fig. 2 shows a schematic structural diagram of a terminal device. It should be understood that the terminal device 100 shown in fig. 2 is only one example of a terminal device, and that the terminal device 100 may have more or fewer components than shown in the figures, may combine two or more components, or may have a different configuration of components. The various components shown in fig. 2 may be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and/or application specific integrated circuits.

As shown in fig. 2, the terminal device includes: processor 110, external memory interface 120, internal memory 121, universal serial bus (universal serial bus, USB) interface 130, charge management module 140, power management module 141, battery 142, antenna 1, antenna 2, mobile communication module 150, wireless communication module 160, audio module 170, speaker 170A, receiver 170B, microphone 170C, headset interface 170D, sensor module 180, keys 190, motor 191, indicator 192, camera 193, display 194, and subscriber identity module (subscriber identification module, SIM) card interface 195, etc. The sensor module 180 may include a pressure sensor, a gyroscope sensor, a barometric sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a proximity sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, a bone conduction sensor, and the like.

The processor 110 may include one or more processing units, such as: the processor 110 may include an application processor (application processor, AP), a modem processor, a graphics processor (graphics processing unit, GPU), an image signal processor (image signal processor, ISP), a controller, a memory, a video codec, a digital signal processor (digital signal processor, DSP), a baseband processor, and/or a neural network processor (neural-network processing unit, NPU), etc. Wherein the different processing units may be separate devices or may be integrated in one or more processors.

The controller may be a neural center and a command center of the terminal device 100. The controller can generate operation control signals according to the instruction operation codes and the time sequence signals to finish the control of instruction fetching and instruction execution.

A memory may also be provided in the processor 110 for storing instructions and data. In some embodiments, the memory in the processor 110 is a cache memory.

In some embodiments, the processor 110 may include one or more interfaces through which electrical connections and control with other modules of the terminal device 100 are made. The interfaces may include an integrated circuit (inter-integrated circuit, I2C) interface, an integrated circuit built-in audio (inter-integrated circuit sound, I2S) interface, a pulse code modulation (pulse code modulation, PCM) interface, a universal asynchronous receiver transmitter (universal asynchronous receiver/transmitter, UART) interface, a mobile industry processor interface (mobile industry processor interface, MIPI), a general-purpose input/output (GPIO) interface, a subscriber identity module (subscriber identity module, SIM) interface, and/or a universal serial bus (universal serial bus, USB) interface, among others. In this embodiment, an audio interface may be used between the processor 110 and the audio module 170, and the audio interface may be, for example, a Soundwire interface.

USB interface 130 is an interface conforming to the USB standard specification, and may specifically be an USB Type C interface or the like. USB interface 130 may be used to electrically connect a power adapter to charge terminal device 100 and may also be used to transfer data between devices. Specifically, the processor 110 is electrically connected to the USB interface 130, and the processor 110 determines the type of device to which the USB interface 130 is connected based on the signal of the USB interface 130. But also to electrically connect headphones (e.g., digital headphones, etc.), through which audio is played. The interface may also be used to electrically connect other terminal devices, such as AR devices, etc.

The charge management module 140 is configured to receive a charge input from a charger. The charger may be a wireless charger or a wired charger (such as a power adapter). The charging management module 140 may also supply power to the terminal device through the power management module 141 while charging the battery 142.

The power management module 141 is used for connecting the battery 142, the charge management module 140 and the processor 110. The power management module 141 receives input from the battery 142 and/or the charge management module 140 and provides power to the processor 110, the internal memory 121, the external memory, the display 194, the camera 193, the wireless communication module 160, and the like. The power management module 141 may also be configured to monitor battery capacity, battery cycle number, battery health (leakage, impedance) and other parameters. In other embodiments, the power management module 141 may also be provided in the processor 110. In other embodiments, the power management module 141 and the charge management module 140 may be disposed in the same device.

The wireless communication function of the terminal device 100 can be implemented by the antenna 1, the antenna 2, the mobile communication module 150, the wireless communication module 160, a modem processor, a baseband processor, and the like.

The antennas 1 and 2 are used for transmitting and receiving electromagnetic wave signals. Each antenna in the terminal device 100 may be used to cover a single or multiple communication bands. Different antennas may also be multiplexed to improve the utilization of the antennas. For example: the antenna 1 may be multiplexed into a diversity antenna of a wireless local area network. In other embodiments, the antenna may be used in conjunction with a tuning switch.

The mobile communication module 150 may provide a solution including 2G/3G/4G/5G wireless communication applied to the terminal device 100. The mobile communication module 150 may include at least one filter, switch, power amplifier, low noise amplifier (low noise amplifier, LNA), etc.

The wireless communication module 160 may provide solutions for wireless communication including wireless local area network (wireless local area networks, WLAN) (e.g., wireless fidelity (wireless fidelity, wi-Fi) network), bluetooth (BT), global navigation satellite system (global navigation satellite system, GNSS), frequency modulation (frequency modulation, FM), near field wireless communication technology (near field communication, NFC), infrared technology (IR), etc., applied to the terminal device 100.

In some embodiments, antenna 1 and mobile communication module 150 of terminal device 100 are coupled, and antenna 2 and wireless communication module 160 are coupled, such that terminal device 100 may communicate with a network and other devices via wireless communication techniques.

The terminal device 100 implements display functions through a GPU, a display screen 194, an application processor, and the like. The GPU is a microprocessor for image processing, and is connected to the display 194 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. Processor 110 may include one or more GPUs that execute program instructions to generate or change display information.

The display screen 194 is used to display images, videos, and the like. The display 194 includes a display panel. In some embodiments, the terminal device 100 may include 1 or N display screens 194, N being a positive integer greater than 1.

The external memory interface 120 may be used to connect an external memory card, such as a Micro SD card, to realize expansion of the memory capability of the terminal device 100. The external memory card communicates with the processor 110 through an external memory interface 120 to implement data storage functions. For example, files such as music, video, etc. are stored in an external memory card.

The internal memory 121 may be used to store computer executable program code including instructions. The processor 110 executes various functional applications of the terminal device 100 and data processing by executing instructions stored in the internal memory 121. The internal memory 121 may include a storage program area and a storage data area. The storage program area may store an application program (such as a sound playing function, an image playing function, etc.) required for at least one function of the operating system, etc. The storage data area may store data (such as audio data, phonebook, etc.) created during use of the terminal device 100, and the like. In addition, the internal memory 121 may include a high-speed random access memory, and may further include a nonvolatile memory such as at least one magnetic disk storage device, a flash memory device, a universal flash memory (universal flash storage, UFS), and the like.

The terminal device 100 may implement audio functions through an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, an application processor, and the like. Such as music playing, recording, etc.

In the present embodiment, the audio module 170 includes a codec 171 and a motor driving module 172. The codec 171 is used to convert digital audio information into an analog audio signal output and also to convert an analog audio input into a digital audio signal. The codec 171 may also be used to encode and decode audio signals to output audio sources. The codec 171 may be provided in the processor 110, may be provided independently, and may also provide a part of functional blocks of the codec 171 in the processor 110. The codec 171 has a plurality of analog-to-digital converters (Analog to Digital Converter, ADC) integrated therein, and correspondingly, the codec 171 further includes a plurality of pins, and the plurality of pins are electrically connected to the ADC in a one-to-one correspondence. The motor driving module 172 is configured to lift and press (e.g. raise to 10V) the audio source output by the codec 171, so as to generate a driving signal for outputting to the speaker 170A, and drive the speaker 170A to operate, which will be described in detail below, and will not be repeated here. The motor driving module 172 may be separately provided, that is, the motor driving module 172 is a separate chip, and in other embodiments, the motor driving module 172 may be provided in the power management module 141; alternatively, the motor driving module 172 may be disposed in the charge management module 140, where the embodiments of the present application are described by taking the motor driving module 172 as an independent example.

The speaker 170A, also referred to as a "horn," is used to convert audio electrical signals into sound signals. The terminal device 100 can listen to music or to handsfree talk through the speaker 170A. In some embodiments, speaker 170A includes voice coil, diaphragm, permanent magnet, etc. When the voice coil of the loudspeaker is electrified with audio alternating current, the voice coil generates an alternating magnetic field under the action of the audio alternating current, namely the magnitude and the direction of the magnetic field generated by the voice coil interact with the audio alternating current to enable the voice coil to move perpendicular to the current direction in the voice coil. Since the voice coil is connected with the diaphragm, the diaphragm is driven to vibrate, and the air is vibrated by the vibration of the diaphragm, thereby making a sound. The larger the current input to the voice coil, the larger the acting force of the magnetic field generated by the voice coil, the larger the amplitude of vibration of the vibrating membrane, and the louder the sound.

A receiver 170B, also referred to as a "earpiece", is used to convert the audio electrical signal into a sound signal. When the terminal device 100 receives a call or voice message, it is possible to receive voice by approaching the receiver 170B to the human ear.

Microphone 170C, also referred to as a "microphone" or "microphone", is used to convert sound signals into electrical signals. When making a call or transmitting voice information, the user can sound near the microphone 170C through the mouth, inputting a sound signal to the microphone 170C. The terminal device 100 may be provided with at least one microphone 170C. In other embodiments, the terminal device 100 may be provided with two microphones 170C, and may implement a noise reduction function in addition to collecting sound signals. In other embodiments, the terminal device 100 may be further provided with three, four or more microphones 170C to collect sound signals, reduce noise, identify the source of sound, implement directional recording functions, etc.

In the embodiment of the present application, the microphone 170C is electrically connected to the ADC in the codec 171 through a pin of the codec 171 to realize the corresponding function.

The earphone interface 170D is used to connect a wired earphone. The earphone interface 170D may be a USB interface 130 or a 3.5mm open mobile terminal platform (open mobile terminal platform, OMTP) standard interface, a american cellular telecommunications industry association (cellular telecommunications industry association of the USA, CTIA) standard interface.

The motor 191 may generate a vibration cue. The motor 191 may be used for incoming call vibration alerting as well as for touch vibration feedback. For example, touch operations acting on different applications (e.g., photographing, audio playing, etc.) may correspond to different vibration feedback effects. The motor 191 may also correspond to different vibration feedback effects by touching different areas of the display screen 194. Different application scenarios (such as time reminding, receiving information, alarm clock, game, etc.) can also correspond to different vibration feedback effects. The touch vibration feedback effect may also support customization. In the embodiment of the present application, the motor 191 may be, for example, a rotor motor. The rotor motor can be driven to vibrate by outputting a power signal through the power management module 141. Of course, the motor 191 may be a linear motor (for example, an X-axis motor or a Z-axis motor), and when the motor 191 is a linear motor, the motor driving module 172 drives the motor, and the driving capability of the motor driving module 172 is generally relatively high.

The following describes a driving circuit provided in an embodiment of the present application.

Referring to fig. 3, fig. 3 shows a schematic structural diagram of a driving circuit according to an embodiment of the present application. As shown in fig. 3, the driving circuit 10 includes a speaker 170A, a codec 171, and a motor driving module 172. The motor drive module 172 is electrically connected to the speaker 170A and the codec 171, respectively, wherein the motor drive module 172 may be electrically connected to the positive and negative terminals of the speaker 170A through, for example, a Soundwire bus or a SPMI (System Power Management Interface) bus. The codec 171 is used to output the sound source to the motor driving module 172. The motor driving module 172 is configured to amplify the audio source and output a first differential signal and a second differential signal to the positive terminal and the negative terminal of the speaker 170A, so as to drive the speaker 170A to operate.

Illustratively, the codec 171 processes (e.g., encodes, etc.) the audio signal to obtain a sound source, which is then output to the motor driving module 172. The motor driving module 172 lifts the sound source (e.g., to 10V) to become a driving signal output to the speaker 170A, and drives the speaker 170A to operate. According to the driving circuit provided by the embodiment of the application, the loudspeaker 170A can be driven to work through the motor driving module 172, and the intelligent power amplification module is not required to be independently arranged, so that the intelligent power amplification module can be saved, the cost of the terminal equipment can be reduced, the occupation ratio of the internal space of the terminal equipment is reduced, and the utilization rate of the internal space of the terminal equipment is improved.

It is contemplated that when the current in the voice coil of speaker 170A is large, the temperature of the voice coil may increase, which may cause speaker 170A to fail or even fail. In the related art, the current of the voice coil and the voltage at two ends of the collected voice coil are determined through the intelligent power amplifier module 30, the impedance of the voice coil is determined based on the voltage and the current, and then the temperature of the voice coil is determined based on the impedance, so as to realize the temperature protection of the voice coil, wherein the specific protection principle can be referred to the existing technology, and the embodiment of the application is not repeated. However, the motor driving module 172 generally does not have a function of collecting the voltage across the voice coil of the speaker 170A, i.e., the motor driving module 172 cannot monitor the impedance of the voice coil in real time, and thus cannot monitor the temperature of the speaker 170A.

In order to monitor the voice coil of speaker 170A in real time. Referring to fig. 4, fig. 4 shows still another schematic structural diagram of a driving circuit according to an embodiment of the present application. As shown in fig. 4, the codec 171 has a first ADC 171A and a second ADC 171B integrated therein. The first ADC 171A is electrically connected to the positive terminal of the speaker 170A, the second ADC 171B is electrically connected to the negative terminal of the speaker 170A, the first ADC 171A is used for collecting the voltage of the positive terminal of the speaker 170A, and the second ADC 171B is used for collecting the voltage of the negative terminal of the speaker 170A, that is, the voltage of the two ends of the voice coil in the speaker 170A. The driving circuit 10 further includes a processing module 40, where the codec 171 may be electrically connected to the processing module 40 through a Soundwire interface, and send the voltage of the positive terminal of the speaker 170A and the voltage of the negative terminal of the speaker 170A to the processing module 40 through the Soundwire interface, where the processing module 40 is configured to determine the current temperature of the voice coil according to the voltage of the positive terminal of the speaker 170A and the voltage of the negative terminal of the speaker 170A, and compare the determined current temperature with a pre-stored correspondence between the temperature and the power of the sound source to determine the power of the sound source at the current temperature, so as to control the codec 171 to output the power of the sound source at the current temperature, i.e. the power does not cause the temperature of the voice coil to be too high, so as to implement temperature protection for the voice coil of the speaker 170A, and avoid damage to the speaker 170A due to the too high temperature of the voice coil.

This is because, as can be seen from the foregoing, the codec 171 is internally integrated with an ADC, and a portion of the ADC is electrically connected to the microphone to realize the corresponding function of the microphone, and the specific function can be seen from the prior art, which is not repeated in the embodiments of the present application. However, there are also some extra ADCs. In this embodiment, the voltages of the positive terminal and the negative terminal of the speaker 170A are collected by using the redundant first ADC 171A and the second ADC 171B, and the structure of collecting the voltages is not required to be separately set, so that the cost is not increased while the temperature monitoring of the voice coil of the speaker 170A is realized.

The processing module 40 may be, for example, a DSP as described above. The DSP may be integrated in the processor 110 or may be separately provided, which is not limited in this embodiment, and since the DSP is provided in the terminal device, the corresponding operation may be implemented without separately providing the processing module 40.

Illustratively, the current temperature of the voice coil is determined from the voltage at the positive terminal of speaker 170A and the voltage at the negative terminal of speaker 170A by: the motor driving module 172 has integrated therein a current sampling structure that can collect in real time the current output from the motor driving module 172, i.e., the current flowing through the voice coil of the speaker 170A, and send the current to the processing module 40. The processing module 40 then determines the impedance (also referred to as a first impedance) of the voice coil based on the current and the voltage at the positive terminal of the speaker 170A and the voltage at the negative terminal of the speaker 170A. The temperature of the voice coil (also referred to as the first temperature) is then determined based on the impedance of the voice coil and the temperature rise coefficient of the voice coil, wherein the voice coil of the speaker 170A is typically supported by a metal conductor, such as copper or aluminum, and the resistance of the voice coil made of the metal conductor has a characteristic that varies with the temperature. The temperature can be measured only by measuring the resistance change of the temperature sensing thermal resistor, and the specific principle can be seen from the prior art, and the embodiment of the application is not repeated.

When the voltages of the positive terminal and the negative terminal of the speaker 170A are collected by the first ADC 171A and the second ADC 171B of the codec 171, the codec 171 is damaged in order to avoid the larger voltage at the speaker 170A. Referring to fig. 5, fig. 5 shows still another schematic structural diagram of a driving circuit according to an embodiment of the present application. As shown in fig. 5, the filter step-down module 50 is disposed between the first ADC 171A of the codec 171 and the positive terminal of the speaker 170A and between the second ADC 171B and the negative terminal of the speaker 170A, the filter step-down module 50 disposed between the first ADC 171A and the positive terminal of the speaker 170A is the first filter step-down module 50A, and the filter step-down module 50 disposed between the second ADC 171B and the negative terminal of the speaker 170A is the second filter step-down module 50B. The first filtering step-down module 50A is configured to filter and step down the voltage at the positive end of the speaker 170A and output the voltage to the first ADC 171A, and the second filtering step-down module 50B is configured to filter and step down the voltage at the negative end of the speaker 170A and output the voltage to the second ADC 171B, so that damage to the codec 171 caused by a larger voltage can be avoided.

It will be appreciated that since the filter step-down module 50 steps down the voltages at the positive and negative terminals of the speaker 170A, the processing module 40 needs to compensate for the reduced voltages before calculating the impedance, i.e., restore the step-down voltages to be converted into real voltages at the positive and negative terminals of the speaker 170A.

As for the specific structure of the filter step-down module 50, the embodiment of the present application does not limit the specific structure of the filter step-down module 50, as long as the codec 171 is not damaged when the voltages of the positive and negative terminals of the speaker 170A are collected.

In a possible implementation manner, referring to fig. 6, fig. 6 shows a schematic diagram of still another structure of a driving circuit provided in an embodiment of the present application. As shown in fig. 6, the filter step-down module 50 includes a blocking capacitor C1, a first resistor R1, and a second resistor R2. The first pole of the blocking capacitor C1 of the first filter step-down module 50A is electrically connected to the positive terminal of the speaker 170A, the second pole of the blocking capacitor C1 is electrically connected to the first terminal of the first resistor R1, the second terminal of the first resistor R1 and the first terminal of the second resistor R2 are both electrically connected to the first ADC 171A of the encoder 171, and the second terminal of the second resistor R2 is grounded. The first pole of the blocking capacitor C1 of the second filter step-down module 50B is electrically connected to the negative terminal of the speaker 170A, the second pole of the blocking capacitor C1 is electrically connected to the first end of the first resistor R1, the second end of the first resistor R1 and the first end of the second resistor R2 are both electrically connected to the second ADC 171B of the codec 171, and the second end of the second resistor R2 is grounded. The blocking capacitor C1 is used for isolating direct current, and the first resistor R1 and the second resistor R2 are used for dividing the alternating current signal after isolating direct current, so that the voltages output to the first ADC 171A and the second ADC 171B of the codec 171 are smaller, and damage to the codec 171 caused by the larger voltages is avoided.

Of course, the manner of determining the current temperature of the voice coil from the voltages of the positive and negative terminals of the speaker 170A is not limited to the above.

Optionally, referring to fig. 7, fig. 7 shows a schematic diagram of another structure of the driving circuit provided in the embodiment of the present application. As shown in fig. 7, a sampling resistor R3 is also provided between the motor drive module 172 and the negative terminal of the speaker 170A. The codec 171 has a third ADC 171C integrated therein. A filter step-down module 50 is also disposed between the third ADC 171C and the first end of the sampling resistor R3, and for distinction, the filter step-down module 50 is a third filter step-down module 50C. The second end of the sampling resistor R3 is electrically connected to the second ADC 171B and the negative end of the speaker 170A, and the third ADC 171C is configured to collect the voltage at the first end of the sampling resistor R3 and after the voltage is filtered and reduced by the third filtering and voltage reducing module 50C, and send the collected voltage to the processing module 40.

It will be appreciated that, since the filtering step-down module 50 performs a step-down process on the voltage at the first end of the sampling resistor R3, the processing module 40 needs to restore the voltage after step-down after receiving the voltage sent by the third ADC 171C.

Then, the processing module 40 determines the difference between the voltages at the two ends of the sampling resistor R3 according to the voltage at the first end of the sampling resistor R3 collected by the third ADC 171C and the voltage at the second end of the sampling resistor R3 collected by the second ADC 171B, and determines the current passing through the sampling resistor R3 according to the difference between the voltages at the two ends of the sampling resistor R3 and the resistance of the sampling resistor R3. Since the sampling resistor R3 is connected in series with the voice coil, the current at the voice coil is equal to the current of the sampling resistor R3. The impedance (also referred to as the second impedance) of the voice coil may be determined by dividing the voltage difference across the voice coil (i.e., the voltage difference between the positive and negative terminals of speaker 170A) by the current in the voice coil. The temperature of the voice coil (also referred to as the second temperature) may then be determined based on the impedance of the voice coil and the temperature rise coefficient of the voice coil.

That is, the impedance of the voice coil may be determined in one of the two ways, and the temperature of the voice coil may be determined based on the impedance. Of course, in order to improve the detection accuracy of the voice coil temperature, the two methods may be performed simultaneously, and then the temperature of the voice coil may be determined based on the average value of the two methods.

The third ADC 171C is also an unnecessary ADC integrated inside the codec 171.

It should be noted that, the manner of determining the temperature of the voice coil includes, but is not limited to, the above examples, and those skilled in the art may set the manner according to the actual situation, so long as the temperature of the voice coil can be determined. For example, a structure for collecting voltages at both ends of the voice coil may be provided in the motor driving module 172, and then the voltages at both ends of the voice coil may be collected by the motor driving module 172, etc.

The embodiment of the present application also provides a protection method for a speaker, which may be applied to, for example, the driving circuit in the embodiment, and has the same beneficial effects, and in the details of this embodiment, which are not described in detail, reference may be made to the embodiments of the driving circuit and the terminal device described above. The protection method of the speaker will be described with reference to the driving circuit shown in fig. 7.

As shown in fig. 8, the protection method of the speaker can be implemented by the following steps:

s801, the voltage of the positive and negative terminals of the speaker 170A after the filtered step-down is obtained, and the current output to the speaker 170A by the motor driving module 172 is obtained.

The voltages obtained by the first ADC 171A and the second ADC 171B of the codec 171 at the positive terminal and the negative terminal of the speaker 170A (i.e., at both ends of the voice coil) and processed by the filtering step-down module 50 are transmitted to the processing module 40.

The motor drive module 172 has integrated therein a current sampling structure that can collect in real time the motor drive module 172 output current, i.e., the current flowing through the voice coil of the speaker 170A, and send the current to the processing module 40.

S802, determining the real voltages of the positive terminal and the negative terminal of the speaker 170A according to the voltages of the positive terminal and the negative terminal of the speaker 170A after the filtering step-down.

Since the first and second filter step-down

modules

50A and 50B step-down the voltage across the voice coil, the processing module 40 needs to compensate for the reduced voltage before calculating the impedance, i.e. restore the voltage after step-down to be converted into the real voltage across the voice coil.

S803 determines the first impedance of the voice coil from the real voltage of the positive and negative terminals of the speaker 170A and the current output to the speaker 170A by the motor drive module 172.

Wherein the processing module 40 determines the impedance (also referred to as the first impedance) of the voice coil based on the current output by the motor drive module 172 to the speaker 170A and the actual voltage across the voice coil.

S804, determining the first current temperature of the voice coil according to the first impedance of the voice coil.

Wherein a current temperature of the voice coil (referred to as a first current temperature) is determined based on the first impedance of the voice coil and the temperature rise coefficient of the voice coil.

S805, comparing the corresponding relation between the first current temperature and the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the first current temperature.

The corresponding relation between the temperature of the voice coil and the power of the sound source, that is, the relation between the temperature of the voice coil and the power of the sound source is reserved in the processing module 40, and if the corresponding sound source power is output according to the relation, the temperature of the voice coil is not too high.

S806 controls the codec 171 to output the power of the sound source at the first current temperature.

To achieve temperature protection of the voice coil of the speaker 170A and to avoid damage to the speaker 170A due to excessive voice coil temperature.

Or alternatively, the process may be performed,

as shown in fig. 9, the protection method of the speaker can be implemented by the following steps:

s901, the voltages of the positive terminal and the negative terminal of the speaker 170A after the filtered step-down are obtained, and the voltage of the first terminal of the sampling resistor after the filtered step-down is obtained.

The third ADC 171C integrated inside the codec 171 collects the voltage at the first end of the sampling resistor R3 and after the voltage is filtered and reduced by the third filtering and reducing module 50C, and transmits the collected voltage to the processing module 40.

S902, determining the real voltages of the positive terminal and the negative terminal of the speaker 170A according to the voltages of the positive terminal and the negative terminal of the speaker 170A after the filter step-down, and determining the real voltage of the first terminal of the sampling resistor according to the voltage of the first terminal of the sampling resistor R3 after the filter step-down.

Since the first and second filter step-down

modules

Since the third filter step-down module 50C performs a step-down process on the voltage at the first end of the sampling resistor R3, when the processing module 40 receives the voltage sent by the third ADC171C, it is necessary to compensate for the reduced voltage, that is, restore the voltage after step-down to convert the voltage into the real voltage at the first end of the sampling resistor R3.

S903, determining the current flowing through the sampling resistor R3 according to the real voltage of the first end of the sampling resistor R3, the real voltage of the negative end of the speaker 170A, and the resistance value of the sampling resistor R3.

The real voltage at the negative terminal of the speaker 170A is the real voltage at the second terminal of the sampling resistor R3, and the difference between the real voltage at the first terminal of the sampling resistor R3 and the real voltage at the second terminal of the sampling resistor R3 divided by the resistance of the sampling resistor R3 is the current flowing through the sampling resistor R3.

S904, a second impedance of the voice coil is determined based on the real voltage across the positive and negative terminals of the speaker 170A and the current flowing through the sampling resistor R3.

The real voltages at the positive and negative ends of the speaker 170A are the voltages at the two ends of the voice coil, and the current flowing through the sampling resistor R3 is the current at the voice coil because the sampling resistor R3 is connected in series with the voice coil. The real voltage across the positive and negative terminals of speaker 170A divided by the current flowing through sampling resistor R3 is the impedance of the voice coil (referred to as the second impedance).

S905, determining a second current temperature of the voice coil according to the second impedance of the voice coil.

The current temperature of the voice coil (referred to as the second temperature) may then be determined based on the second impedance of the voice coil and the temperature rise coefficient of the voice coil.

S906, comparing the second current temperature with the corresponding relation between the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the second current temperature.

S907, the control codec 171 outputs the power of the sound source at the second current temperature.

The present embodiment also provides a computer storage medium having stored therein computer instructions which, when executed on a terminal device, cause the terminal device to execute the above-described related method steps to implement the charging control method in the above-described embodiments.

The present embodiment also provides a computer program product which, when run on a computer, causes the computer to perform the above-described related steps to implement the charge control method in the above-described embodiments.

In addition, embodiments of the present application also provide an apparatus, which may be specifically a chip, a component, or a module, and may include a processor and a memory connected to each other; the memory is used for storing computer-executable instructions, and when the device is running, the processor can execute the computer-executable instructions stored in the memory, so that the chip executes the charging control method in each method embodiment.

The terminal device (such as a mobile phone) provided in this embodiment, the computer storage medium, the computer program product or the chip are used to execute the corresponding method provided above, so that the beneficial effects that can be achieved by the terminal device can refer to the beneficial effects in the corresponding method provided above, and will not be described herein.

It will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of modules or units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The above embodiments are merely for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A driving circuit, characterized by being applied to a terminal device; the terminal device includes a motor; the terminal device further comprises a motor driving module for driving the linear motor;

the driving circuit includes: a speaker, a codec, and the motor driving module; the motor driving module is respectively and electrically connected with the loudspeaker and the coder-decoder;

the coder is used for outputting the sound source to the motor driving module;

the motor driving module is used for amplifying the sound source and outputting the amplified sound source to the loudspeaker so as to drive the loudspeaker to operate;

the driving circuit further comprises a processing module which is electrically connected with the coder;

The coder comprises a first analog-to-digital converter and a second analog-to-digital converter, the first analog-to-digital converter is used for collecting the voltage of the positive end of the loudspeaker and sending the voltage to the processing module, and the second analog-to-digital converter is used for collecting the voltage of the negative end of the loudspeaker and sending the voltage to the processing module;

the motor driving module is electrically connected with the processing module; the motor driving module is internally integrated with a current sampling structure, and the current sampling structure is used for collecting current output to the loudspeaker and sending the current to the processing module;

the processing module is used for determining a first temperature of the voice coil of the loudspeaker according to the voltage of the positive end of the loudspeaker, the voltage of the negative end of the loudspeaker and the current; the method comprises the steps of,

the driving circuit further comprises a sampling resistor, a first end of the sampling resistor is electrically connected with the motor driving module, and a second end of the sampling resistor is electrically connected with the negative end of the loudspeaker;

the coder and the decoder further comprise a third analog-to-digital converter, wherein the third analog-to-digital converter is used for collecting the voltage of the first end of the sampling resistor and sending the voltage to the processing module;

The processing module is used for determining the voltage difference between two ends of the sampling resistor according to the voltage of the first end of the sampling resistor and the voltage of the negative end of the loudspeaker, determining the current of the loudspeaker according to the voltage difference and the resistance value of the sampling resistor, and determining the second temperature of the voice coil according to the voltage of the positive end of the loudspeaker, the voltage of the negative end of the loudspeaker and the current;

determining a current temperature of the voice coil according to an average value of the first temperature and the second temperature; and comparing the corresponding relation between the current temperature and the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the current temperature so as to control the encoder to output the power of the sound source at the current temperature.

2. The drive circuit of claim 1, further comprising a first filter step-down module and a second filter step-down module; the first filtering voltage reduction module is positioned between the first analog-to-digital converter and the positive end of the loudspeaker and is used for filtering and reducing the voltage of the positive end of the loudspeaker and then outputting the voltage to the first analog-to-digital converter, and the second filtering voltage reduction module is positioned between the second analog-to-digital converter and the negative end of the loudspeaker and is used for filtering and reducing the voltage of the negative end of the loudspeaker and then outputting the voltage to the second analog-to-digital converter.

3. The drive circuit of claim 2, wherein the first filter step-down module and the second filter step-down module each comprise a blocking capacitor, a first resistor and a second resistor, a first pole of the blocking capacitor of the first filter step-down module is electrically connected to the positive speaker terminal, a second pole of the blocking capacitor is electrically connected to a first end of the first resistor, a second end of the first resistor and a first end of the second resistor are electrically connected to the first analog-to-digital converter, and a second end of the second resistor is grounded;

the first pole of the blocking capacitor of the second filtering voltage reduction module is electrically connected with the negative end of the loudspeaker, the second pole of the blocking capacitor is electrically connected with the first end of the first resistor, the second end of the first resistor and the first end of the second resistor are electrically connected with the second analog-to-digital converter, and the second end of the second resistor is grounded.

4. The driving circuit of claim 1, further comprising a third filter step-down module, located between the first end of the sampling resistor and the third analog-to-digital converter, for filtering and step-down the voltage at the first end of the sampling resistor and outputting the voltage to the third analog-to-digital converter.

5. The drive circuit of claim 4, wherein the third filter step-down module comprises a blocking capacitor, a first resistor and a second resistor, a first pole of the blocking capacitor of the third filter step-down module is electrically connected to the first end of the sampling resistor, a second pole of the blocking capacitor is electrically connected to the first end of the first resistor, a second end of the first resistor and a first end of the second resistor are both electrically connected to the third analog-to-digital converter, and a second end of the second resistor is grounded.

6. The drive circuit of any one of claims 1-5, wherein the processing module comprises a digital signal processor.

7. A terminal device comprising the drive circuit of any one of claims 1-6.

8. A method of protecting a loudspeaker, applied to a drive circuit as claimed in any one of claims 1 to 6; the protection method comprises the following steps:

respectively acquiring the voltages of the positive end and the negative end of the loudspeaker, the voltage of the first end of the sampling resistor and the current output to the loudspeaker;

determining a first impedance of a voice coil in the loudspeaker according to voltages of a positive end and a negative end of the loudspeaker and a current output to the loudspeaker, and determining a second impedance of the voice coil in the loudspeaker according to the voltage of the first end of the sampling resistor, the voltage of the negative end of the loudspeaker and the resistance value of the sampling resistor;

Determining a first temperature of the voice coil based on the first impedance, and determining a second temperature of the voice coil based on the second impedance;

determining a current temperature of the voice coil according to an average value of the first temperature and the second temperature;

comparing the corresponding relation between the current temperature and the pre-stored temperature and the power of the sound source, and determining the power of the sound source at the current temperature;

and controlling the coder to output the power of the sound source at the current temperature.

9. The protection method according to claim 8, wherein obtaining the voltages of the positive and negative terminals of the speaker, respectively, comprises:

obtaining voltages of a positive end and a negative end of the loudspeaker after filtering and depressurization;

the voltages of the positive terminal and the negative terminal of the loudspeaker are determined according to the voltages of the positive terminal and the negative terminal of the loudspeaker after the filtering step-down.

10. The method of claim 8, wherein obtaining the voltage at the first end of the sampling resistor comprises:

acquiring the voltage of the first end of the sampling resistor after filtering and reducing the voltage;

and determining the voltage of the first end of the sampling resistor according to the voltage of the first end of the sampling resistor after the filtering step-down.

11. A computer readable storage medium comprising a computer program, characterized in that the computer program, when run on a terminal device, causes the terminal device to perform the method of protecting a loudspeaker according to any of claims 8-10.