AI intelligent voice interaction frame

Abstract

The application relates to the technical field of interactive frame circuit design, in particular to an AI intelligent voice interactive frame; the AI intelligent voice interactive frame comprises a main control unit, an auxiliary control unit, a microphone acquisition circuit, a power amplifier audio back acquisition circuit and a human body induction circuit; an input end of the microphone acquisition circuit is used for acquiring a differential audio signal emitted by an external signal source and outputs the differential audio signal to the auxiliary control unit; the power amplifier audio back acquisition circuit is used for generating an echo feedback signal and outputs the echo feedback signal to the auxiliary control unit; the auxiliary control unit is used for receiving a human body induction signal, the differential audio signal and the echo feedback signal, processing the signals to obtain a voice control signal and outputting the voice control signal to the main control unit; and the main control unit is used for receiving the voice control signal and executing display driving and multimedia control according to the voice control signal.

Description

Technical Field

[0001] This invention relates to the field of interactive photo frame circuit design technology, and in particular to an AI intelligent voice interactive photo frame. Background Technology

[0002] Currently, most smart voice-interactive photo frame products on the market suffer from technical defects such as incomplete function integration, inaccurate interactive response, and poor user experience. Most products lack multi-functional control involving human body sensing, microphone audio acquisition, and amplifier echo feedback. Either the lack of human body sensing leads to excessive power consumption, or the microphone-acquired audio signal is easily interfered with and distorted, and the absence of an effective echo feedback mechanism results in issues such as voice recognition misjudgment and howling. Furthermore, the control units in most products have unclear division of labor, low signal processing efficiency, and an inability to quickly integrate multiple input signals and output effective control commands. This leads to lag in display driving and multimedia control response, failing to meet users' needs for convenient and accurate smart interaction, thus limiting the market promotion and improvement of the application experience of smart voice-interactive photo frames. Summary of the Invention

[0003] The solution to the technical problem of this invention is: an AI intelligent voice-interactive photo frame, comprising: a main control unit, a secondary control unit, a microphone acquisition circuit, a power amplifier audio feedback circuit, and a human body sensing circuit; the output terminal of the microphone acquisition circuit, the power amplifier audio feedback circuit, and the human body sensing circuit are all connected to the input terminal of the secondary control unit; the input terminal of the main control unit is connected to the output terminal of the secondary control unit; the human body sensing circuit is used to detect the presence signal of a human body, convert it into a human body sensing signal, and output it to the secondary control unit; the input terminal of the microphone acquisition circuit is used to acquire differential audio signals emitted by an external signal source and output them to the secondary control unit; the power amplifier audio feedback circuit is used to generate echo feedback signals and output them to the secondary control unit; the secondary control unit is used to receive the human body sensing signal, the differential audio signal, and the echo feedback signal, process them to obtain a voice control signal, and output it to the main control unit; the main control unit is used to receive the voice control signal and execute display driving and multimedia control according to the voice control signal.

[0004] Further, the power amplifier audio feedback circuit includes a power amplifier chip, a signal conditioning unit, a mode control unit, a power supply and ground unit, a speaker driver output unit, and a differential audio feedback unit. The output terminals of the mode control unit and the signal conditioning unit are both connected to the input terminal of the power amplifier chip. The power supply terminal of the power amplifier chip is connected to the power supply terminal of the power supply and ground unit, and the ground terminal of the power amplifier chip is connected to the ground terminal of the power supply and ground unit. The input terminals of the signal conditioning unit and the mode control unit are both connected to the output terminal of the secondary control unit. The input terminals of the differential audio feedback unit and the speaker driver output unit are both connected to the output terminal of the power amplifier chip. The output terminal of the speaker driver output unit is used to connect to an external speaker. The output terminal of the differential audio feedback unit is connected to the secondary control unit. The input terminals of the units are connected; the signal conditioning unit is used to receive the original audio signal output by the sub-control unit, perform noise reduction processing to obtain a clean audio signal, and output it to the power amplifier chip; the mode control unit is used to receive the control command output by the sub-control unit, convert it into a level control signal, and control the power amplifier chip's power amplifier operating mode; the power supply and ground unit is used to supply power to the power amplifier chip; the power amplifier chip is used to receive the audio signal, convert it into a differential power audio signal, and output it to the speaker driver output unit; the speaker driver output unit is used to receive the differential power audio signal, convert it into a drive signal, and control the external speaker according to the drive signal; the differential audio feedback unit is used to collect the audio signal from the output terminal of the power amplifier chip, convert it into an echo feedback signal, and transmit it back to the sub-control unit.

[0005] Further, the power amplifier chip includes pins MUTE, BYPASS, NC, INN, VDD, GND, OUT-, OUT+, and an integrated amplifier unit; pin VDD is located at the power supply terminal of the integrated amplifier unit; pin GND is located at the ground terminal of the integrated amplifier unit; pins MUTE, BYPASS, and NC are all located at the control terminal of the integrated amplifier unit; pin INN is located at the input terminal of the integrated amplifier unit; pins OUT- and OUT+ are both located at the control terminal of the integrated amplifier unit. At the output of the integrated amplifier unit, pins OUT- and OUT+ are both connected to the input of the speaker driver output unit; pins OUT- and OUT+ are also connected to the input of the differential audio retrieval unit; pins MUTE, BYPASS, and NC are all connected to the output of the mode control unit; the output of the signal conditioning unit is connected to pin INN; the power supply terminal of the power supply and ground unit is connected to pin VDD; and the ground terminal of the power supply and ground unit is connected to pin GND.

[0006] Furthermore, the signal conditioning unit includes a coupling capacitor C1, a current-limiting resistor R5, and a feedback resistor R4; one end of the coupling capacitor C1 is connected to the output terminal of the sub-control unit, and the other end of the coupling capacitor C1 is connected to one end of the current-limiting resistor R5; the other end of the current-limiting resistor R5 is connected to the pin INN; one end of the feedback resistor R4 is connected to the node between the current-limiting resistor R5 and the pin INN, and the other end of the feedback resistor R4 is connected to the pin OUT+.

[0007] Furthermore, the mode control unit includes a current-limiting pull-up resistor R16, a coupling capacitor C13, a current-limiting resistor R20, and a current-limiting resistor R22; one end of the current-limiting pull-up resistor R16 is connected to the output terminal of the sub-control unit, and the other end of the current-limiting pull-up resistor R16 is connected to the pin MUTE; one end of the coupling capacitor C13 is used to receive external control signals, and one end of the current-limiting resistor R20 and the pin BYPASS are both connected to the other end of the coupling capacitor C13; the other end of the current-limiting resistor R20 is connected to the pin NC; one end of the current-limiting resistor R22 is connected to the output terminal of the sub-control unit, and the other end of the current-limiting resistor R22 is connected to the pin NC.

[0008] Further, the power supply and ground unit includes a power supply filter capacitor C11, a high-frequency filter capacitor C10, a power supply node VDD, and a ground node GND; the power supply node VDD is connected to the pin VDD, and the ground node GND is connected to the pin GND; one end of the power supply filter capacitor C11 is connected to the power supply node VDD, and the other end of the power supply filter capacitor C11 is connected to the ground node GND; one end of the high-frequency filter capacitor C10 is connected to the power supply node VDD, and the other end of the high-frequency filter capacitor C10 is connected to the ground node GND; the power supply filter capacitor C11 and the high-frequency filter capacitor C10 are connected in parallel.

[0009] Furthermore, the speaker driver output unit includes a speaker interface CN2 and pins 1, 2 and 3 provided on the speaker interface CN2. Pin 1 is connected to pin OUT-, pin OUT+ is connected to pin 2, and pin 3 is connected to the ground node GND.

[0010] Furthermore, the differential audio backtracking unit includes a coupling capacitor C39, a coupling capacitor C40, a current-limiting resistor R17, a coupling capacitor C41, and a backtracking signal output terminal DACL; one end of the coupling capacitor C39 is connected to pin 1, and the other end of the coupling capacitor C39 forms a backtracking positive phase signal path; one end of the coupling capacitor C40 is connected to pin 2, and the other end of the coupling capacitor C40 is connected to one end of the current-limiting resistor R17; the other end of the current-limiting resistor R17 is connected to one end of the coupling capacitor C41, and the other end of the coupling capacitor C41 is connected to the backtracking signal output terminal DACL, forming a backtracking inverted phase signal path; the output terminal of the differential audio backtracking unit is connected to the backtracking signal output terminal DACL.

[0011] Furthermore, the microphone acquisition circuit includes a microphone bias unit, a microphone body, a signal filtering unit, a signal coupling unit, and a signal output unit; the output terminal of the microphone bias unit is connected to the power supply terminal of the microphone body, the output terminal of the microphone body is connected to the input terminal of the signal filtering unit, the output terminal of the signal filtering unit is connected to the input terminal of the signal coupling unit, and the output terminal of the signal coupling unit is connected to the input terminal of the signal output unit; the power supply terminal of the microphone bias unit is connected to the power supply and ground unit, and the ground terminal of the microphone bias unit is connected to the ground terminal of the power supply and ground unit; the output terminal of the signal output unit is connected to the input terminal of the sub-control unit.

[0012] Further, the microphone bias unit includes a pull-up resistor R8, a pull-down resistor R6, a DACVDD power supply node, a reference ground node, and a master control node AGND. One end of the pull-up resistor R8 is connected to the DACVDD power supply node, and the other end of the pull-up resistor R8 is connected to pin M1+ of the microphone body. One end of the pull-down resistor R6 is connected to pin M1- of the microphone body, and the other end of the pull-down resistor R6 is connected to the reference ground node. The reference ground node is connected to the master control node AGND. The pull-up resistor R8 and the pull-down resistor R6 are connected in series to form a voltage divider circuit. The signal filtering unit includes a power supply decoupling capacitor C5 and a high-frequency suppression capacitor C2. One end of the power supply decoupling capacitor C5 is connected to the DACVDD power supply node. The power supply node is connected to the power supply decoupling capacitor C5, and the other end of the power supply decoupling capacitor C5 is connected to the reference ground node. One end of the high-frequency suppression capacitor C2 is connected to the pin M1+, and the other end of the high-frequency suppression capacitor C2 is connected to the pin M1-. The signal coupling unit includes a DC blocking capacitor C12. One end of the DC blocking capacitor C12 is connected to the pin M1+. The signal output unit includes a signal interface MIC3. The other end of the DC blocking capacitor C12 is connected to the signal interface MIC3, and the output terminal of the signal interface MIC3 is connected to the input terminal of the sub-control unit. The DACVDD power supply node is connected to the power supply terminal of the power supply and ground unit. The reference ground node is connected to the ground terminal of the power supply and ground unit.

[0013] The beneficial effects of this invention are as follows: This invention achieves an organic combination of intelligent voice interaction and low-power operation by centrally processing human body sensing signals, differential audio signals, and echo feedback signals through a secondary control unit; the human body sensing circuit uses a dedicated detection chip, which can stably identify human approach and departure actions, and the output trigger level does not require polling by the main control unit, reducing system standby power consumption; the microphone uses a differential input method, effectively suppressing environmental noise and improving voice acquisition quality; the power amplifier audio feedback circuit provides echo reference, working with the secondary control unit to achieve efficient echo cancellation and improve voice recognition accuracy; the secondary control unit completes signal preprocessing, noise reduction, scene judgment, and command generation, reducing the computational burden on the main control unit, allowing the main control unit to focus on display driving and multimedia control, resulting in smoother and more stable system operation; the overall solution has advantages such as strong anti-interference capability, fast response speed, and low standby power consumption, while the modular design facilitates production and upgrades, effectively improving the user experience, battery life, and operational reliability of the smart photo frame. Attached Figure Description

[0014] Figure 1 This is an overall system structure diagram of an AI intelligent voice-interactive photo frame according to the present invention; Figure 2 This is a schematic diagram of the power amplifier audio feedback circuit of an AI intelligent voice interactive photo frame according to the present invention. Figure 3 This is a schematic diagram of the microphone acquisition circuit of an AI-powered intelligent voice-interactive photo frame according to the present invention. Detailed Implementation

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments have been briefly explained above. Obviously, the described drawings are only a part of the embodiments of the present invention, and not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0016] The following will clearly and completely describe the concept, specific structure, and technical effects of the present invention in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. Furthermore, all connection relationships mentioned herein do not simply refer to direct connection of components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this invention can be combined interactively without contradicting each other.

[0017] Reference Figures 1-3An AI-powered intelligent voice-interactive photo frame includes: a main control unit, a secondary control unit, a microphone acquisition circuit, a power amplifier audio feedback circuit, and a human body sensing circuit; the output of the microphone acquisition circuit, the power amplifier audio feedback circuit, and the human body sensing circuit are all connected to the input of the secondary control unit; the input of the main control unit is connected to the output of the secondary control unit; the human body sensing circuit detects the presence of a human body, converts it into a human body sensing signal, and outputs it to the secondary control unit. The human body sensing circuit uses a dedicated human presence detection chip, which integrates an infrared pyroelectric / millimeter-wave sensing unit, signal amplification, and noise filtering circuit, and can stably detect the approach / departure of a human body; when a human body is detected entering the sensing range, the chip outputs a valid trigger level; when no human body is detected, it returns to the default level, eliminating the need for the main control unit to continuously poll the I / O port; the input of the microphone acquisition circuit is used to acquire signals from external signal sources. The system outputs differential audio signals to the secondary control unit. Ambient noise is suppressed through differential input, and the original voice signal is transmitted to the secondary control unit for subsequent voice recognition. The power amplifier audio feedback circuit generates echo feedback signals and outputs them to the secondary control unit. When the picture frame plays audio, the sound emitted by the speaker is collected a second time by the microphone, creating echo interference that affects the accuracy of voice recognition. The power amplifier audio feedback circuit synchronously collects the original audio signal output by the power amplifier and transmits it as an "echo reference signal" to the secondary control unit, providing a benchmark for echo cancellation and filtering speaker self-echoes. The secondary control unit receives human body induction signals, differential audio signals, and echo feedback signals, processes them to obtain voice control signals, and outputs them to the main control unit. The main control unit receives the voice control signals and executes display driving and multimedia control based on them. In this embodiment, the secondary control unit centrally processes human body sensing signals, differential audio signals, and echo feedback signals, achieving an organic combination of intelligent voice interaction and low-power operation. The human body sensing circuit uses a dedicated detection chip, which can stably identify human body approaching and leaving, and the output trigger level does not require polling by the main control unit, reducing system standby power consumption. The microphone uses a differential input method, effectively suppressing environmental noise and improving voice acquisition quality. The power amplifier audio feedback circuit provides echo reference, working with the secondary control unit to achieve efficient echo cancellation and improve voice recognition accuracy. The secondary control unit completes signal preprocessing, noise reduction, scene judgment, and command generation, reducing the computational burden on the main control unit, allowing the main control unit to focus on display driving and multimedia control, resulting in smoother and more stable system operation. The overall solution has advantages such as strong anti-interference capability, fast response speed, and low standby power consumption. At the same time, the modular design facilitates production and upgrades, effectively improving the user experience, battery life, and operational reliability of the smart photo frame.

[0018] In this embodiment, the main control unit, based on the AC7916AB microcontroller, serves as the brain of the entire AI photo frame system. Its circuit design revolves around the system clock, power management, peripheral interfaces, debugging, and expansion functions. The clock system comprises two parts: first, an external high-speed crystal oscillator Y1 (24MHz) and an internal oscillation circuit form the main clock source, providing a stable system clock for the main control unit MCU1 via the OSCI and OSCO pins, ensuring synchronization between instruction execution and peripheral timing; second, an external 32.768kHz crystal oscillator Y2 provides the system with a real-time clock (RTC) reference, supporting time retention in low-power standby mode. All crystal oscillator circuits are equipped with… Matching capacitors (C25 / C27, C100 / C101) are used to optimize the resonant frequency and ensure a stable and reliable clock signal. The power supply section adopts a multi-domain design, providing multiple independent power rails for the main control unit MCU1, including the main power supply VDD, analog power supply AHVDD, DAC power supply DACVDD, etc. Each power rail is equipped with decoupling capacitors (such as C23, C28, C26, C31) to filter out power ripple and high-frequency noise, providing a clean and stable power environment for digital circuits, analog circuits, and peripheral interfaces, and avoiding power crosstalk affecting system stability. The power network (such as DCVDD14, WFVDD14) also uses a filter capacitor array (C17 / C15) The power quality of the C26, C24 / C22 / C19 / C18 modules is further optimized to meet the power supply requirements of different modules. In terms of peripheral interfaces, MCU1 exposes display control pins such as LCD_CLK, LCD_RST, LCD_CS, and LCD_RS, supporting external display drivers. It also features audio-related pins such as DACL and DAR (for communication with the FLASH memory chip), supporting program debugging, data transmission, and peripheral expansion. It works in conjunction with the power amplifier's audio feedback circuit to achieve audio playback and echo cancellation control. Communication interfaces include a UART debug interface (TX / RX), an I2C interface (SDA / SCL), and an SPI interface (for F...). (LASH memory chip communication), supporting program debugging, data transmission, and peripheral expansion; the sensor and control interface reserves the INT1 interrupt input pin, which can be connected to peripherals such as human body sensors and buttons; it is also equipped with USB interfaces such as FUSBOM and USB_DM / DP to support data transmission and power supply; in terms of debugging interface, a UART_DCDUG interface is reserved to support program download, online debugging, and system log output, which facilitates functional verification and fault diagnosis during the development phase; the low-power control module includes the VBAT backup power pin and the SW power control pin, which supports the system's low-power standby mode and can control the power status through software to realize the energy-saving strategy of being woken up by people and going into standby mode when people leave; In this embodiment, the secondary control unit, based on the AK8073 microcontroller (U4), serves as the auxiliary control and event processing unit for the AI ​​intelligent voice-interactive photo frame. It can independently handle tasks such as low-power interaction, button detection, battery management, and communication handshake, thereby reducing the computational burden on the main control unit (MCU1). The circuit is built around the power system, peripheral interfaces, communication links, and control input modules, possessing low-power operation characteristics. It is responsible for power status detection, button command parsing, battery status monitoring, peripheral communication control, and achieves low-power management and functional linkage with the main control unit. In the power system, the VDD pin is the main power supply terminal for the chip, powered by the U5_VDD power rail, and equipped with a decoupling capacitor C42 (4.7µF). F) Filtering out power supply ripple provides a stable operating power supply for the chip; the GND pin is grounded to construct a complete power supply loop, while reserving a BAT battery detection interface to collect battery voltage signals through the BATADC pin, realizing battery power monitoring and low power warning, providing data support for the system's low power consumption strategy; In terms of communication interface, the SPI communication interface consists of PB0 (DAT) pin and PB1 (CLK) pin forming an SPI bus, with R23 (4.7R) and R25 (4.7R) current limiting resistors to realize SPI communication with the memory chip or main control unit, supporting data read and write and command transmission; at the same time, PA0 (SPI0_CS) serves as the SPI chip select signal to realize device selection and communication control. To ensure stable data transmission, the UART serial communication link is formed by the PA3 / TX (UART_RX) and PA4 / RX (UART_TX) pins, used for bidirectional data transmission with the main control unit (MCU1). This enables control command issuance, status data reporting, and debugging information exchange, serving as the communication channel for the main and secondary control units. The button input interface has reserved button input circuitry on the PB3 (KEY1) and PB4 (KEY2) pins, allowing for external physical buttons to be connected for manual wake-up, function switching, and other user-interactive operations, supporting direct user control of the device status. The button circuit adopts a typical pull-up input design, triggering an interrupt response by detecting level changes, eliminating the need for a separate main control unit. The control unit polls the I / O ports to reduce system idle power consumption; the PB2 (POWER) pin is the power control signal terminal, which can output high and low level signals to control the power supply on and off, and work with the main control unit to implement energy-saving strategies such as low-power standby and wake-up; the PB5, PB6, PA5, and PB7 pins are reserved expansion interfaces, which can be connected to external sensors, indicator lights and other peripherals to support future function expansion; the circuit also has multiple anti-interference designs: the SPI bus is connected in series with a 4.7R current-limiting resistor to suppress surge current, protect chip pins, and reduce signal reflection to improve communication stability; the VDD pin is equipped with a decoupling capacitor to filter out power supply noise, avoid the impact of power fluctuations on the chip's operating state, and improve the circuit's anti-interference capability; In this embodiment, the human body sensing circuit is the scene triggering module of the AI ​​intelligent voice interactive photo frame. It is based on the NS312 human presence detection chip (CGQ1) and consists of a power supply filtering circuit. Its output is connected to the signal input of the secondary control unit, converting the human presence signal into a trigger signal to provide a basis for low power consumption and intelligent interaction. The core detection unit uses the NS312 high-sensitivity human presence detection chip, which integrates a sensing probe, signal amplification, noise filtering, and comparison output circuit. It can stably detect human activity signals and output standard high and low level signals without the need for additional signal processing circuits, directly adapting to the IO level standard of the secondary control unit. The power supply and anti-interference circuit chip is powered by the system's 3.3V power supply, with a 1μF filter capacitor C4 connected in parallel at the power supply end to filter out power supply ripple and high-frequency interference, preventing power supply noise from causing false triggering of the chip. In case of detection failure, the chip ensures detection stability in complex electromagnetic environments. The output (OUT pin) of the signal output and transmission link chip is directly connected to the signal input of the secondary control unit. The presence signal of a human body is converted into a digital trigger signal and then transmitted to the secondary control unit. This link is a direct connection design without additional conversion circuitry, resulting in low signal transmission delay. When a human body is detected entering the sensing range, the chip outputs a valid trigger level, which is transmitted to the secondary control unit. After receiving the signal, the secondary control unit combines it with the current system state (such as low-power mode or standby mode) to generate a corresponding wake-up / start command, triggering the main control unit to perform actions such as screen lighting, initiating voice interaction, and playing content. When a human body leaves the sensing range, the chip outputs a default level, and the secondary control unit can control the main control unit to turn off the screen, audio, and other peripherals according to a preset delay strategy, so that the whole device enters a low-power standby mode.

[0019] The power amplifier audio sampling circuit includes a power amplifier chip, a signal conditioning unit, a mode control unit, a power supply and ground unit, a speaker driver output unit, and a differential audio sampling unit. The output terminals of the mode control unit and the signal conditioning unit are both connected to the input terminal of the power amplifier chip. The power supply terminal of the power amplifier chip is connected to the power supply and ground unit, and the ground terminal of the power amplifier chip is connected to the ground terminal of the power supply and ground unit. The input terminals of the signal conditioning unit and the mode control unit are both connected to the output terminal of the secondary control unit. The signal conditioning unit receives the raw audio signal output from the secondary control unit and, through internal filtering, noise reduction, and DC blocking, removes noise and power supply interference from the signal. The interference and DC component are removed to obtain a clean audio signal with a high signal-to-noise ratio, which is then sent to the power amplifier chip to avoid speaker distortion and excessive background noise caused by amplified interference signals. The input terminals of the differential audio retrieval unit and the speaker driver output unit are both connected to the output terminal of the power amplifier chip. The output terminal of the speaker driver output unit is used to connect to an external speaker. The output terminal of the differential audio retrieval unit is connected to the input terminal of the sub-control unit. The signal conditioning unit is used to receive the original audio signal output by the sub-control unit, perform noise reduction processing to obtain a clean audio signal, and output it to the power amplifier chip. The mode control unit is used to receive the control commands output by the sub-control unit and convert them into level signals. The control signal controls the power amplifier chip's operating mode; the mode control unit receives control commands from the sub-control unit, converts the digital commands into corresponding level control signals, and adjusts the power amplifier chip's operating mode. This allows switching between mute mode, low-power standby mode, Class D amplification mode (high efficiency, low heat generation, suitable for battery power), and Class AB amplification mode (good sound quality, low noise floor, suitable for close-range listening), meeting the needs of different scenarios such as playback, standby, and noise reduction. The power supply and ground unit supplies power to the power amplifier chip; it provides a stable operating power supply to the power amplifier chip while constructing a standardized grounding loop to suppress power ripple, electromagnetic interference, and common-mode noise, ensuring the power amplifier chip operates continuously and stably under complex operating conditions. To avoid audio dropouts and noise caused by power supply fluctuations, the power amplifier chip receives audio signals, converts them into differential power audio signals, and outputs them to the speaker driver output unit. The power amplifier chip receives the conditioned clean audio signal, converts the low-voltage small signal into a high-power differential audio signal, and features sufficient output power, strong driving capability, and low distortion, providing adequate driving capability for the speaker. The speaker driver output unit receives the differential power audio signal output by the power amplifier chip, converts it into a driving signal adapted to the external speaker, and controls the external speaker according to the driving signal. The speaker driver output unit receives the differential power audio signal output by the power amplifier chip, converts it into a driving signal adapted to the external speaker, and achieves high-fidelity playback of voice and audio content.The differential audio feedback unit is used to collect audio signals from the output of the power amplifier chip, convert them into echo feedback signals, and transmit them back to the sub-control unit; the differential audio feedback unit directly and synchronously collects audio output signals from the output of the power amplifier chip, converts the power signals into low-voltage echo feedback signals adapted to the input of the sub-control unit, and transmits them back to the sub-control unit in real time, providing a reference source for acoustic echo cancellation; In this embodiment, the original audio signal is filtered, denoised, and DC blocked by the signal conditioning unit, effectively eliminating noise and DC interference, improving the audio signal-to-noise ratio, and resulting in pure, distortion-free, and low-noise speaker output. The mode control unit can flexibly switch between mute, low-power standby, and Class D / AB amplification modes according to the sub-controller's instructions, balancing efficient battery life and a superior listening experience, adapting to various usage scenarios. The power supply and ground unit provides stable power supply and standardized grounding, suppressing power ripple and electromagnetic interference, ensuring long-term stable operation of the power amplifier. The power amplifier chip uses differential power output, with strong driving capability and excellent anti-interference performance, working in conjunction with the speaker drive output unit to achieve high-fidelity audio playback. The differential audio feedback unit can synchronously collect the output signal in real time and transmit it back to the sub-controller, providing a reference for acoustic echo cancellation, solving the echo interference problem at the hardware level, and improving the accuracy of voice recognition and the stability of interaction. The overall circuit structure is clear, highly reliable, and easy to mass-produce, comprehensively optimizing the audio performance and voice interaction experience of the smart photo frame.

[0020] The power amplifier chip includes pins MUTE, BYPASS, NC, INN, VDD, GND, OUT-, OUT+, and an integrated amplifier unit. Pin VDD is located on the power supply terminal of the integrated amplifier unit, providing it with operating power. Pin GND is located on the ground terminal of the integrated amplifier unit, forming a stable grounding loop. The independent power supply and grounding settings effectively isolate power supply noise, ensuring stable operating voltage under different loads and providing a reliable foundation for audio amplification. Pins MUTE, BYPASS, and NC are all located on the control terminal of the integrated amplifier unit. The BYPASS and NC pins are both located at the control terminal of the integrated amplifier unit, forming the control terminal together. The MUTE pin is used to receive mute commands for rapid mute control; the BYPASS pin is used for internal bias regulation and noise suppression; the NC pin is unused, enhancing circuit layout flexibility and anti-interference margin, and inputs mode configuration and mute control signals to the integrated amplifier unit; the INN pin is located at the input terminal of the integrated amplifier unit. INN is a single-ended audio input pin that receives pre-processed clean audio signals, preventing interference signals from entering the amplification link, ensuring distortion-free and noise-free sound after amplification, and inputs the audio signal to be amplified to the integrated amplifier unit; the OUT- and OUT+ pins are both located at the integrated amplifier unit. On the output terminals of the unit, pins OUT- and OUT+ are both connected to the input terminals of the speaker driver output unit, and pins OUT- and OUT+ are also connected to the input terminals of the differential audio retrieval unit; pins MUTE, BYPASS, and NC are all connected to the output terminals of the mode control unit. The mode control unit can stably output control signals, achieving precise control through pins MUTE, BYPASS, and NC, effectively avoiding signal interference and device damage, ensuring clear and stable audio playback, improving system reliability and user experience, and meeting the audio output and interaction needs of smart devices; the output terminal of the signal conditioning unit is connected to pin INN, through reasonable... The signal processing ensures the integrity and stability of the audio signal, guaranteeing the normal operation of the power amplifier. The power supply and ground unit's power supply terminal is connected to the VDD pin, and the ground terminal is connected to the GND pin, achieving a stable connection between power supply and grounding. This effectively avoids problems such as voltage fluctuations and abnormal ground potential, reduces signal interference, improves the circuit's anti-interference capability, ensures stable audio signal transmission, enhances system reliability, and meets the usage requirements of AI intelligent voice interaction photo frames. Pins OUT- and OUT+ are differential output terminals, both connected to the input terminals of the speaker driver output unit and the differential audio feedback unit, sending out the differential power audio signal output by the integrated amplifier unit to drive the speaker to produce sound.The differential output structure can significantly cancel common-mode interference and improve signal transmission stability and drive reliability; In this embodiment, through a clearly structured and fully functional power amplifier chip design, the independent power supply pin VDD and ground pin GND are configured separately to effectively isolate power supply noise and ensure stable operating voltage of the chip under various load conditions, providing a reliable working foundation for audio amplification. The control port composed of pins MUTE, BYPASS, and NC can realize mute, bias voltage regulation, noise suppression, and flexible configuration, improving circuit adaptability and anti-interference capability, resulting in purer audio output and lower noise floor. Pin INN single-ended audio input can receive pre-processed pure signals to prevent interference from entering the amplification link, ensuring distortion-free and noise-free output sound quality. Pin OUT... The OUT+ pin adopts a differential power output structure, which can cancel common-mode interference, improve signal transmission stability and anti-interference ability, and at the same time have stronger speaker driving capability. The overall solution has high integration, clear pin functions, and simple circuit, which can improve audio playback quality, reduce system power consumption, and enhance operational reliability, making the audio performance of the smart voice interactive photo frame more stable and the voice interaction more accurate.

[0021] The signal conditioning unit includes a coupling capacitor C1, a current-limiting resistor R5, and a feedback resistor R4. One end of the coupling capacitor C1 is connected to the output terminal of the secondary control unit, and the other end of the coupling capacitor C1 is connected to the secondary control unit, receiving the original DACL audio signal. It serves to block DC and pass AC, blocking the DC bias voltage contained in the signal and coupling only the AC audio signal to the subsequent stage, preventing DC components from entering the power amplifier chip and causing speaker distortion, overheating, or even damage. The other end of the coupling capacitor C1 is connected to one end of the current-limiting resistor R5. The other end of the current-limiting resistor R5 is connected to the pin INN. The current-limiting resistor R5 is connected in series in the signal transmission path, on the one hand, to block the DC bias voltage contained in the signal, and on the other hand, to pass the feedback resistor R4. The signal is current-limited to prevent transient high current from impacting the power amplifier chip's input pin INN; on the other hand, it achieves input impedance matching, making the operation of the pre- and post-amplifier circuits more stable and reducing signal reflection and interference; one end of the feedback resistor R4 is connected to the node between the current-limiting resistor R5 and the pin INN, and the other end of the feedback resistor R4 is connected to the pin OUT+. The feedback resistor R4 is connected across the power amplifier's input pin INN and output pin OUT+, forming an AC negative feedback loop. By sampling the output signal and feeding it back to the input, it stabilizes the overall amplification gain, suppresses nonlinear distortion, and avoids problems such as clipping, noise, and excessive background noise in the audio, making the output sound more linear, smooth, and natural. In this embodiment, the signal conditioning unit performs complete preprocessing and optimization of the original audio signal through the cooperation of coupling capacitor C1, current-limiting resistor R5, and feedback resistor R4. Coupling capacitor C1 effectively blocks the DC bias voltage, retaining only the AC audio signal transmission, avoiding DC components that could cause speaker distortion, overheating, or damage, thus improving the safety and purity of the audio output. Current-limiting resistor R5 limits the signal current, preventing transient high current from impacting the power amplifier chip's input pins, while also achieving impedance matching between the front and rear stages, reducing signal reflection and electromagnetic interference, and improving circuit stability. Feedback resistor R4 forms an AC negative feedback loop, stabilizing the audio amplification gain, suppressing nonlinear distortion, clipping, and excessive background noise, resulting in a more linear, smooth, and natural output sound. The overall circuit structure is simple, highly reliable, and low-cost, improving audio signal quality and providing the power amplifier with a clean, stable, and low-distortion input signal, effectively improving the voice clarity and audio playback effect of the intelligent voice-interactive photo frame.

[0022] The mode control unit includes a current-limiting pull-up resistor R16, a coupling capacitor C13, a current-limiting resistor R20, and a current-limiting resistor R22. One end of the current-limiting pull-up resistor R16 is connected to the output terminal of the sub-control unit, and the other end is connected to the MUTE pin, serving as a pull-up regulator and current-limiting protection to prevent overshoot or high current from damaging the MUTE pin, while ensuring a stable and reliable mute level and achieving fast and clean mute switching. One end of the coupling capacitor C13 is used to receive external control signals, and the coupling capacitor C13 is used to receive external BYPASS control signals, filtering, regulating, and reducing noise in the bias signal to stabilize the internal operating point of the chip and reduce audio noise floor and nonlinear distortion. A current-limiting resistor R20 is connected in series in the signal path to achieve current limiting and impedance matching, improving the stability of the BYPASS control signal. One end of the current-limiting resistor R20 and the BYPASS pin are both connected to the other end of the coupling capacitor C13; the other end of the current-limiting resistor R20 is connected to the NC pin; one end of the current-limiting resistor R22 is connected to the output terminal of the sub-control unit, and the other end of the current-limiting resistor R22 is connected to the NC pin. The current-limiting resistor R22 is used for level configuration, anti-interference, and reserved mode expansion, so that the NC pin is no longer floating, avoiding interference, false triggering or abnormal operation caused by floating, and improving the overall anti-interference capability and operational reliability of the chip. In this embodiment, the mode control unit constitutes a complete mode control and protection circuit through current-limiting pull-up resistors, coupling capacitors, and multiple current-limiting resistors, which can improve the working stability of the power amplifier chip and the audio output quality. The current-limiting pull-up resistor R16 realizes pull-up regulation and current-limiting protection for the MUTE pin, avoiding overshoot and high current damage to the chip, and ensuring fast, clean, and noise-free mute switching. The coupling capacitor C13 and the current-limiting resistor R20 work together to filter, regulate, and reduce noise for the BYPASS bias signal, stabilize the internal operating point of the chip, effectively reduce audio noise floor and nonlinear distortion, and improve the purity of sound quality. The current-limiting resistor R22 reliably configures the level of the NC pin, avoiding interference, false triggering, and abnormal operation caused by the pin being floating, and enhancing the overall anti-interference capability and operational stability of the chip. The entire circuit uses passive components, has a simple structure, low cost, high reliability, and is easy to mass-produce, and can achieve precise control of the power amplifier's working mode, providing a stable, low-noise, and high-quality audio playback guarantee for the intelligent voice interactive photo frame.

[0023] The power supply and ground unit includes a power supply filter capacitor C11, a high-frequency filter capacitor C10, a power supply node VDD, and a ground node GND. The power supply node VDD is connected to the pin VDD and serves as the energy input port for the entire power amplifier chip, continuously providing a stable operating voltage to the integrated amplification unit inside the chip, ensuring the normal operation of audio amplification, mode switching, and other functions. The ground node GND is connected to the pin GND, providing a unified and fixed reference zero potential for the entire circuit, ensuring that audio signals and control signals have a consistent potential reference, avoiding problems such as audio distortion, increased noise floor, and abnormal operation caused by ground potential fluctuations, common-mode noise, and potential difference interference. One end of the power supply filter capacitor C11 is connected to the power supply node VDD, and the other end is connected to the ground node GND. One end of the high-frequency filter capacitor C10 is connected to the power supply node VDD, and the high-frequency filter capacitor C10... The other end of capacitor C10 is connected to the grounding node GND; the power supply filter capacitor C11 and the high-frequency filter capacitor C10 are connected in parallel, and the power supply filter capacitor C11 and the high-frequency filter capacitor C10 are connected in parallel across the power supply node VDD and the grounding node GND to form a full-band power purification circuit covering low frequency to high frequency. The power supply filter capacitor C11 has a relatively large capacitance value, and its main function is to filter out low-frequency ripple, mains interference, large current load fluctuations, voltage drops and other problems in the power supply, stabilize the overall power supply voltage, and avoid sound interruption, distortion and insufficient dynamics caused by power fluctuations; the high-frequency filter capacitor C10 has a small capacitance value and excellent high-frequency characteristics. It is specially used to suppress high-frequency noise, switching spikes, electromagnetic interference and radio frequency noise on the power line, and prevent high-frequency interference from entering the power amplifier amplification link, causing howling, noise and excessive background noise. The parallel connection of the two can achieve high and low frequency complementarity, completely eliminate power supply noise, and provide the purest working voltage for the power amplifier chip; In this embodiment, the power supply and ground unit, through a standardized power supply grounding architecture and a dual-capacitor parallel filtering design, provides a stable, clean, and highly anti-interference guarantee for the power amplifier chip, improving the reliability of the power amplifier and the audio output quality. The power supply node VDD and the grounding node GND are set independently, providing a stable power supply and a unified reference zero potential for the power amplifier chip, effectively avoiding ground potential fluctuations, common-mode noise, and potential difference interference, preventing audio distortion, increased background noise, and abnormal operation. The power supply filter capacitor C11 and the high-frequency filter capacitor C10 are connected in parallel to form a full-band purification circuit, which can filter out low-frequency impurities such as low-frequency ripple and mains interference, stabilize the power supply voltage, and avoid sound interruption and distortion. It can also suppress high-frequency noise, electromagnetic interference, and other high-frequency noise, eliminating howling and background noise, and providing a clean operating voltage for the power amplifier chip. The overall circuit structure is simple, low-cost, and highly reliable, which can improve the audio purity, system anti-interference capability, and overall operational stability of the smart voice interaction frame, and optimize voice playback and interactive experience.

[0024] The speaker driver output unit includes a speaker interface CN2 and pins 1, 2 and 3 provided on the speaker interface CN2. Pin 1 is connected to pin OUT-, pin OUT+ is connected to pin 2, and pin 3 is connected to the ground node GND. In this embodiment, pin 1 is connected to the power amplifier chip pin OUT-, and pin 2 is connected to the power amplifier chip pin OUT+, forming a dual-channel output channel for differential audio signals. The differential power audio signal, processed by the integrated amplification unit of the power amplifier chip, is directly transmitted to the external speaker through pins 1 and 2, achieving stable transmission and sound drive of the differential audio power signal. Pin 3 is connected to the ground node GND, providing a unified and reliable system reference ground potential for the speaker interface and the external speaker, constructing a complete signal return path, and providing a ground reference for the external speaker. The speaker driver output unit uses a dedicated speaker interface partitioned pin design to match the differential output terminal of the power amplifier chip. The interface can fully transmit differential power audio signals, giving full play to the advantages of differential transmission in resisting common-mode interference, effectively suppressing electromagnetic crosstalk and environmental noise, and reducing audio playback distortion, noise, and background noise. By independently setting a grounding pin and connecting it to the system ground node, it provides a stable reference potential and a complete signal return path for the speaker, avoiding current noise, howling, and malfunctions caused by unstable ground potential. The interface pin definitions are clear and the wiring is neat, facilitating quick plug-in assembly of external speakers and adapting to mass production assembly requirements. At the same time, the structure is simple and the connection is reliable, and it can stably carry audio power output for a long time, improving the clarity and stability of audio playback in the smart voice interaction photo frame and the overall reliability of the device.

[0025] The differential audio retrieval unit includes coupling capacitor C39, coupling capacitor C40, current-limiting resistor R17, coupling capacitor C41, and a retrieval signal output terminal DACL. One end of coupling capacitor C39 is connected to pin 1, and the other end of coupling capacitor C39 forms a retrieval positive phase signal path. Coupling capacitor C39 is responsible for acquiring the inverted signal (corresponding to power amplifier OUT-output), C40 is responsible for acquiring the positive phase signal (corresponding to power amplifier OUT+output), and C41 is responsible for secondary coupling of the inverted signal after current-limiting filtering to further isolate noise and ensure the purity of the inverted signal, forming a symmetrical differential retrieval signal with the positive phase signal acquired by C40, thus improving the stability of signal transmission. One end of coupling capacitor C40 is connected to pin 2, and the other end of coupling capacitor C40 is connected to one end of current-limiting resistor R17. The other end of current-limiting resistor R17 is connected to one end of coupling capacitor C41, and current-limiting resistor R17 is connected in series between coupling capacitor C40 and coupling capacitor C41. Between the capacitors, an RC filter network is formed with the capacitors before and after the stage to suppress high-frequency noise in the sampled signal. Coupling capacitors C39, C40, and C41 are respectively set in the differential signal path to achieve DC isolation and transmit only AC audio signals. The other end of the coupling capacitor C41 is connected to the sampled signal output terminal DACL to form a sampled inverted signal path. The output terminal of the differential audio sampled unit is connected to the sampled signal output terminal DACL. Coupling capacitors C39, C40, and C41 can effectively block various DC components and only allow the AC audio signal output by the power amplifier to pass through, avoiding DC interference from affecting the subsequent circuit. The sampled signal output terminal DACL serves as the unified output terminal of the sampled signal. It receives the differential audio sampled signal after being processed by coupling capacitors C39, C40, current limiting resistor R17, and C41, and normalizes it into a signal format that meets the input requirements of the subsequent sub-control unit, realizing the interface between the differential audio sampled signal and the subsequent circuit. In this embodiment, DC isolation is achieved through coupling capacitors C39, C40, and C41, effectively blocking DC interference, preventing damage to downstream control units and chips, and ensuring circuit operational stability. The current-limiting resistor R17 and the capacitors before and after the current stage form an RC filter network, which efficiently filters out high-frequency noise, switching spikes, and other interference, improving the purity of the acquired signal. The differential acquisition and transmission design can effectively cancel common-mode interference, enabling efficient transmission and purification of the acquired signal, improving the accuracy and fluency of voice interaction, and optimizing the user experience. At the same time, the current-limiting and DC-blocking design further enhances the system reliability and service life.

[0026] The microphone acquisition circuit includes a microphone bias unit, a microphone body, a signal filtering unit, a signal coupling unit, and a signal output unit. The output terminal of the microphone bias unit is connected to the power supply terminal of the microphone body. The microphone bias unit includes a pull-up resistor R8, a pull-down resistor R6, a DACVDD power node, a reference ground node, and a master control node AGND. One end of the pull-up resistor R8 is connected to the DACVDD power node, and the other end of the pull-up resistor R8 is connected to pin M1+ of the microphone body. One end of the pull-down resistor R6 is connected to pin M1- of the microphone body, and the other end of the pull-down resistor R6 is connected to the reference ground node. The reference ground node is connected to the master control node AGND. The pull-up resistor R8 and the pull-down resistor R6 are connected in series to form a voltage divider circuit. The signal filtering unit includes a power supply decoupling capacitor C5 and a high-frequency suppression capacitor C2. One end of the power supply decoupling capacitor C5 is connected to the power supply input terminal of the microphone body. The DACVDD power node is connected to the power supply, and the other end of the power supply decoupling capacitor C5 is connected to the reference ground node; one end of the high-frequency suppression capacitor C2 is connected to the pin M1+, and the other end of the high-frequency suppression capacitor C2 is connected to the pin M1-; the signal coupling unit includes a DC blocking capacitor C12; one end of the DC blocking capacitor C12 is connected to the pin M1+; the signal output unit includes a signal interface MIC3; the other end of the DC blocking capacitor C12 is connected to the signal interface MIC3, and the output terminal of the signal interface MIC3 is connected to the input terminal of the sub-control unit; the DACVDD power node is connected to the power supply terminal of the power supply and ground unit; the reference ground node is connected to the ground terminal of the power supply and ground unit; the microphone bias unit includes a pull-up resistor R8 (3.3K) and a pull-down resistor R6 (3.3K), which are connected by the pull-up resistor R8 (3.3K) and the pull-down resistor R6 (3.3K).A voltage divider circuit (3K) is formed in series. The power supply terminal is connected to the DACVDD power node, and the ground terminal is connected to the main control node AGND through the reference ground node. This provides symmetrical DC bias voltages to pins M1+ and M1- of the microphone body, enabling the field-effect transistors inside the electret condenser microphone to establish a stable static operating point. This ensures that the microphone operates in the linear amplification region, providing the basic conditions for sound-to-electric conversion and avoiding signal distortion or sensitivity reduction due to abnormal bias voltage. The output terminal of the microphone body is connected to the input terminal of the signal filtering unit. An electret condenser microphone is used, with its positive terminal M1+ and negative terminal M1- connected to the voltage divider of the microphone bias unit. The node converts the acquired external sound vibrations into a weak differential raw electrical signal. This differential raw electrical signal simultaneously contains an AC audio component synchronized with the sound and a DC bias component introduced by the bias voltage, responsible for realizing the conversion of sound energy into electrical energy. The output of the signal filtering unit is connected to the input of the signal coupling unit. The signal filtering unit consists of a power supply decoupling capacitor C5 (1uF) and a high-frequency suppression capacitor C2 (1nF). The power supply decoupling capacitor C5 is connected in parallel between DACVDD and ground, filtering out power supply ripple, low-frequency noise, and power fluctuations, providing a stable power supply environment for the microphone acquisition circuit. The high-frequency suppression capacitor C2 is connected in parallel to the microphone... The output of the microphone body suppresses high-frequency electromagnetic interference and radio frequency noise in the differential raw electrical signal, weakening the impact of high-frequency noise on the audio signal, improving the signal-to-noise ratio, and reducing the noise processing pressure on subsequent circuits. The output of the signal coupling unit is connected to the input of the signal output unit. The signal coupling unit consists of a DC blocking capacitor C12 (1uF), which is connected in series between the M1+ output of the microphone body and the signal output unit. It can isolate the DC bias component in the differential raw electrical signal, allowing only the AC audio signal to pass through, preventing the DC bias component from entering the circuit of the subsequent auxiliary control unit, and preventing the circuit from failing to properly acquire the AC signal due to DC bias. The system achieves impedance matching between the microphone body and the subsequent circuitry to ensure signal transmission integrity. The power supply terminal of the microphone bias unit is connected to the power supply and ground terminal of the power supply and ground unit, and the ground terminal of the microphone bias unit is connected to the ground terminal of the power supply and ground unit. The output terminal of the signal output unit is connected to the input terminal of the sub-control unit. This signal output unit, composed of the signal interface MIC3, receives the filtered and coupled clean AC audio signal and transmits it to the input terminal of the sub-control unit, providing a reliable audio signal input for subsequent voice acquisition, echo cancellation, and voice recognition processing, thus completing the signal output of the entire microphone acquisition chain. In this embodiment, a microphone audio acquisition link is constructed through the cooperation of a microphone bias unit, a microphone body, a signal filtering unit, a signal coupling unit, and a signal output unit. The microphone bias unit provides a stable operating point for the microphone, ensuring that it operates in the linear amplification region and avoiding signal distortion. The power supply decoupling and high-frequency suppression filtering design effectively filters out power supply ripple and electromagnetic interference, improving the signal-to-noise ratio of the audio signal. The DC blocking coupling circuit isolates the DC component, preventing the subsequent circuit from being affected by DC bias, while achieving impedance matching to ensure signal transmission integrity. This effectively improves the stability and anti-interference capability of audio acquisition, provides high-quality raw signals for subsequent voice processing, simplifies the circuit structure, reduces system design complexity and cost, and has good compatibility and reliability.

[0027] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. An AI-powered intelligent voice-interactive photo frame, characterized in that, include: Main control unit, secondary control unit, microphone acquisition circuit, power amplifier audio feedback circuit and human body sensing circuit; The output of the microphone acquisition circuit, the power amplifier audio feedback circuit, and the human body sensing circuit are all connected to the input of the secondary control unit; the input of the main control unit is connected to the output of the secondary control unit; the human body sensing circuit is used to detect the presence of a human body, convert it into a human body sensing signal, and output it to the secondary control unit; the input of the microphone acquisition circuit is used to acquire differential audio signals emitted by an external signal source and output them to the secondary control unit; the power amplifier audio feedback circuit is used to generate echo feedback signals and output them to the secondary control unit; the secondary control unit is used to receive the human body sensing signal, the differential audio signal, and the echo feedback signal, process them to obtain a voice control signal, and output it to the main control unit; the main control unit is used to receive the voice control signal and execute display driving and multimedia control according to the voice control signal.

2. The AI-powered intelligent voice-interactive photo frame as described in claim 1, characterized in that, The power amplifier audio feedback circuit includes a power amplifier chip, a signal conditioning unit, a mode control unit, a power supply and ground unit, a speaker driver output unit, and a differential audio feedback unit. The output terminals of the mode control unit and the signal conditioning unit are both connected to the input terminal of the power amplifier chip. The power supply terminal of the power amplifier chip is connected to the power supply terminal of the power supply and ground unit, and the ground terminal of the power amplifier chip is connected to the ground terminal of the power supply and ground unit. The input terminals of the signal conditioning unit and the mode control unit are both connected to the output terminal of the secondary control unit. The input terminals of the differential audio feedback unit and the speaker driver output unit are both connected to the output terminal of the power amplifier chip. The output terminal of the speaker driver output unit is used to connect to an external speaker. The output of the differential audio sampling unit is connected to the input of the secondary control unit; the signal conditioning unit receives the original audio signal output by the secondary control unit, performs noise reduction processing to obtain a clean audio signal, and outputs it to the power amplifier chip; the mode control unit receives the control command output by the secondary control unit, converts it into a level control signal, and controls the power amplifier chip's operating mode; the power supply and ground unit supplies power to the power amplifier chip; the power amplifier chip receives the audio signal, converts it into a differential power audio signal, and outputs it to the speaker driver output unit; the speaker driver output unit receives the differential power audio signal, converts it into a drive signal, and controls the external speaker according to the drive signal; the differential audio sampling unit collects the audio signal from the output of the power amplifier chip, converts it into an echo feedback signal, and sends it back to the secondary control unit.

3. The AI-powered intelligent voice-interactive photo frame as described in claim 2, characterized in that, The power amplifier chip includes pins MUTE, BYPASS, NC, INN, VDD, GND, OUT-, OUT+, and an integrated amplifier unit. Pin VDD is located at the power supply terminal of the integrated amplifier unit; pin GND is located at the ground terminal of the integrated amplifier unit; pins MUTE, BYPASS, and NC are all located at the control terminal of the integrated amplifier unit; pin INN is located at the input terminal of the integrated amplifier unit; pins OUT- and OUT+ are both located at the ground terminal of the integrated amplifier unit. On the output terminal of the integrated amplifier unit, pins OUT- and OUT+ are both connected to the input terminal of the speaker driver output unit; pins OUT- and OUT+ are also connected to the input terminal of the differential audio retrieval unit; pins MUTE, BYPASS, and NC are all connected to the output terminal of the mode control unit; the output terminal of the signal conditioning unit is connected to pin INN; the power supply terminal of the power supply and ground unit is connected to pin VDD; and the ground terminal of the power supply and ground unit is connected to pin GND.

4. The AI ​​intelligent voice-interactive photo frame as described in claim 3, characterized in that, The signal conditioning unit includes a coupling capacitor C1, a current-limiting resistor R5, and a feedback resistor R4. One end of the coupling capacitor C1 is connected to the output terminal of the sub-control unit, and the other end of the coupling capacitor C1 is connected to one end of the current-limiting resistor R5. The other end of the current-limiting resistor R5 is connected to the pin INN. One end of the feedback resistor R4 is connected to the node between the current-limiting resistor R5 and the pin INN, and the other end of the feedback resistor R4 is connected to the pin OUT+.

5. The AI ​​intelligent voice-interactive photo frame as described in claim 3, characterized in that, The mode control unit includes a current-limiting pull-up resistor R16, a coupling capacitor C13, a current-limiting resistor R20, and a current-limiting resistor R22. One end of the current-limiting pull-up resistor R16 is connected to the output terminal of the sub-control unit, and the other end of the current-limiting pull-up resistor R16 is connected to the pin MUTE. One end of the coupling capacitor C13 is used to receive external control signals, and one end of the current-limiting resistor R20 and the pin BYPASS are both connected to the other end of the coupling capacitor C13. The other end of the current-limiting resistor R20 is connected to the pin NC. One end of the current-limiting resistor R22 is connected to the output terminal of the sub-control unit, and the other end of the current-limiting resistor R22 is connected to the pin NC.

6. The AI ​​intelligent voice-interactive photo frame as described in claim 3, characterized in that, The power supply and ground unit includes a power supply filter capacitor C11, a high-frequency filter capacitor C10, a power supply node VDD, and a ground node GND; the power supply node VDD is connected to the pin VDD, and the ground node GND is connected to the pin GND; one end of the power supply filter capacitor C11 is connected to the power supply node VDD, and the other end of the power supply filter capacitor C11 is connected to the ground node GND; one end of the high-frequency filter capacitor C10 is connected to the power supply node VDD, and the other end of the high-frequency filter capacitor C10 is connected to the ground node GND; the power supply filter capacitor C11 and the high-frequency filter capacitor C10 are connected in parallel.

7. The AI ​​intelligent voice-interactive photo frame as described in claim 6, characterized in that, The speaker driver output unit includes a speaker interface CN2 and pins 1, 2 and 3 on the speaker interface CN2. Pin 1 is connected to pin OUT-, pin OUT+ is connected to pin 2, and pin 3 is connected to the ground node GND.

8. The AI ​​intelligent voice-interactive photo frame as described in claim 7, characterized in that, The differential audio acquisition unit includes a coupling capacitor C39, a coupling capacitor C40, a current-limiting resistor R17, a coupling capacitor C41, and an acquisition signal output terminal DACL. One end of the coupling capacitor C39 is connected to pin 1, and the other end of the coupling capacitor C39 forms a positive phase acquisition signal path. One end of the coupling capacitor C40 is connected to pin 2, and the other end of the coupling capacitor C40 is connected to one end of the current-limiting resistor R17. The other end of the current-limiting resistor R17 is connected to one end of the coupling capacitor C41, and the other end of the coupling capacitor C41 is connected to the acquisition signal output terminal DACL, forming an inverted phase acquisition signal path. The output terminal of the differential audio acquisition unit is connected to the acquisition signal output terminal DACL.

9. The AI ​​intelligent voice-interactive photo frame as described in claim 2, characterized in that, The microphone acquisition circuit includes a microphone bias unit, a microphone body, a signal filtering unit, a signal coupling unit, and a signal output unit. The output terminal of the microphone bias unit is connected to the power supply terminal of the microphone body, the output terminal of the microphone body is connected to the input terminal of the signal filtering unit, the output terminal of the signal filtering unit is connected to the input terminal of the signal coupling unit, and the output terminal of the signal coupling unit is connected to the input terminal of the signal output unit. The power supply terminal of the microphone bias unit is connected to the power supply and ground terminal of the power supply and ground unit, and the ground terminal of the microphone bias unit is connected to the ground terminal of the power supply and ground unit. The output terminal of the signal output unit is connected to the input terminal of the sub-control unit.

10. The AI-powered intelligent voice-interactive photo frame as described in claim 9, characterized in that, The microphone bias unit includes a pull-up resistor R8, a pull-down resistor R6, a DACVDD power supply node, a reference ground node, and a master control node AGND. One end of the pull-up resistor R8 is connected to the DACVDD power supply node, and the other end is connected to pin M1+ of the microphone body. One end of the pull-down resistor R6 is connected to pin M1- of the microphone body, and the other end is connected to the reference ground node. The reference ground node is connected to the master control node AGND. The pull-up resistor R8 and the pull-down resistor R6 are connected in series to form a voltage divider circuit. The signal filtering unit includes a power supply decoupling capacitor C5 and a high-frequency suppression capacitor C2. One end of the power supply decoupling capacitor C5 is connected to the DACVDD power supply node. The nodes are connected, with one end of the power decoupling capacitor C5 connected to the reference ground node; one end of the high-frequency suppression capacitor C2 is connected to the pin M1+, and the other end of the high-frequency suppression capacitor C2 is connected to the pin M1-; the signal coupling unit includes a DC blocking capacitor C12; one end of the DC blocking capacitor C12 is connected to the pin M1+; the signal output unit includes a signal interface MIC3; the other end of the DC blocking capacitor C12 is connected to the signal interface MIC3, and the output terminal of the signal interface MIC3 is connected to the input terminal of the sub-control unit; the DACVDD power node is connected to the power terminal of the power supply and ground unit; the reference ground node is connected to the ground terminal of the power supply and ground unit.

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