A multi-format output conversion device based on ARC audio signals

Abstract

The utility model relates to a multi -format output conversion device based on ARC audio signal relates to audio signal conversion field especially relates to a multi -system output conversion device based on ARC audio signal, it includes casing, HDMI joint, circuit board, output joint, circuit board sets up in casing, the both ends of casing are provided with HDMI joint, output joint respectively, the output joint is SPDIF output interface or RCA interface end. Circuit includes main control unit, ARC receiving port, waveform shaping logic chip, SPDIF output interface, ARC receiving port passes through HDMI interface and connects television equipment, and TV passes through ARC receiving port and mutually controls communication with main control unit, and the output end of ARC receiving port is connected waveform shaping logic chip, and the output end of waveform shaping logic chip is connected SPDIF output interface. Provide a kind of multi -format output conversion device based on ARC audio signal, it supports the two kinds of output modes of SPDIF and RCA simultaneously, improves the compatibility of equipment;It is compact in structure, and it is convenient to integrate in television or projector peripheral accessories.

Description

Technical Field

[0001] This utility model relates to the field of audio signal conversion, and in particular to a multi-standard output conversion device based on ARC audio signals. Background Technology

[0002] With the widespread adoption of home theater systems and smart TVs, the High Definition Multimedia Interface (HDMI) has gradually become the mainstream standard for audio and video signal transmission. The HDMI interface not only transmits high-definition video signals but also integrates audio transmission capabilities. Among these features, the Audio Return Channel (ARC) technology allows the TV to transmit audio signals back to the sound system or amplifier via HDMI cables, simplifying wiring and enhancing the convenience of the audio system.

[0003] However, the current market offers a wide variety of audio playback devices, some of which support digital audio interfaces (such as SPDIF optical or coaxial), while other older devices only support analog audio inputs (such as RCA interfaces). Since ARC outputs audio signals in digital format (SPDIF protocol), this somewhat limits its compatibility with different types of audio devices.

[0004] In existing technologies, devices for ARC audio signal conversion typically only have a single output method. For example, one type of product converts ARC audio to SPDIF signal output, which is only suitable for power amplifier systems with digital decoding capabilities; another type converts ARC audio to analog audio through complex circuit structures, but this is costly, has complex control logic, and is susceptible to interference. These products have the following shortcomings in practical applications: single function, poor adaptability, complex wiring, prone to errors, complex structure, and poor stability. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings and deficiencies of existing technologies by providing a multi-format output conversion device based on ARC audio signals. It simultaneously supports both SPDIF and RCA output methods, thus improving device compatibility. It has a compact structure and is easy to integrate into peripheral accessories for televisions or projectors.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: it includes a housing A1, an HDMI connector A2, a circuit board A3, and an output connector A4. The circuit board A3 is disposed inside the housing A1, and the two ends of the housing A1 are respectively provided with an HDMI connector A2 and an output connector A4; the output connector A4 is an SPDIF output connector 4 or an RCA interface 9.

[0007] The circuit board A3 includes a main control unit 1, an ARC receiving port 2, a waveform shaping logic chip 3, and an SPDIF output interface 4. The ARC receiving port 2 is connected to a television device via an HDMI connector A2. The television communicates with the main control unit 1 through the ARC receiving port 2. The output of the ARC receiving port 2 is connected to the waveform shaping logic chip 3, and the output of the waveform shaping logic chip 3 is connected to the SPDIF output interface 4.

[0008] The output connector A4 is the SPDIF output interface 4. The SPDIF output interface 4 is a coaxial interface, which uses a standard RCA connector and coaxial cable to transmit digital signals; the cable is inexpensive and has good compatibility; however, its anti-interference performance is not as good as that of optical fiber.

[0009] The main control unit 1 uses the MU18 series chip.

[0010] The waveform shaping logic chip 3 is an SN74LVC2GU04 chip.

[0011] The working principle of this invention is as follows: Audio signal reception and output are achieved based on HDMI ARC (Audio Return Channel) technology. After the device is powered on, the main control unit 1 first completes initialization and starts HPD (Hot Plug Detect) detection to determine if a TV or host is connected. If a TV connection is detected, the main control unit 1 then communicates with the TV via the CEC (Consumer Electronics Control) protocol to establish an ARC audio transmission channel. After the TV successfully activates ARC, the audio signal is transmitted back to the device in SPDIF format via the HDMI line.

[0012] After the SPDIF signal is input, it first undergoes waveform shaping and buffering via the SN74LVC2GU04 logic chip to ensure that the signal conforms to the digital audio output standard. The shaped SPDIF signal is then transmitted to external audio devices, such as power amplifiers or speaker systems, via optical or coaxial output interfaces to achieve digital audio output playback. Throughout the process, the main control unit 1 coordinates the ARC connection status, controls power supply and signal path switching, thereby achieving plug-and-play, stable digital audio transmission functionality.

[0013] The advantages of this invention, achieved by adopting the above technical solution, are as follows: It can stably receive ARC audio signals from a TV or host and output them in SPDIF format through a simple circuit, eliminating the need for additional audio decoding or conversion processing and simplifying the audio link structure. This invention uses a small number of general-purpose chips (such as SN74LVC2GU04) to implement the core functions, eliminating complex audio decoding and amplification modules, effectively reducing material costs and design complexity, and making it suitable for miniaturized module integration. By using a logic buffer to shape the waveform of the SPDIF signal, signal integrity is effectively improved, avoiding glitches and interference, making it suitable for most digital power amplifiers, decoders, and other SPDIF audio receiving devices. The main control unit 1 has HPD detection and CEC communication functions, which can automatically identify the TV insertion status and start ARC channel communication, supporting "plug-and-play" application scenarios and improving user experience. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 yes Figure 1 Internal structure diagram;

[0017] Figure 3 yes Figure 2 Another viewpoint;

[0018] Figure 4 This is a schematic diagram of the circuit structure of Example 1;

[0019] Figure 5 This is a schematic diagram of the circuit structure of Example 2.

[0020] Explanation of reference numerals in the attached diagram: Housing A1, HDMI connector A2, circuit board A3, output connector A4, main control unit 1, ARC receiver port 2, waveform shaping logic chip 3, SPDIF output interface 4, audio receiver chip 6, digital-to-analog converter chip 7, operational amplifier chip 8, RCA interface 9. Detailed Implementation

[0021] Example 1

[0022] See Figure 1-4As shown, this embodiment includes a housing A1, an HDMI connector A2, a circuit board A3, and an output connector A4. The circuit board A3 is disposed inside the housing A1. The HDMI connector A2 and the output connector A4 are respectively disposed at both ends of the housing A1. The output connector A4 is an SPDIF output interface 4. The circuit of the circuit board A3 includes a main control unit 1, an ARC receiving port 2, a waveform shaping logic chip 3, and an SPDIF output interface 4. The ARC receiving port 2 is connected to the television device through the HDMI connector A2. The ARC receiving port 2 communicates and controls the main control unit 1. The output end of the ARC receiving port 2 is connected to the waveform shaping logic chip 3, and the output end of the waveform shaping logic chip 3 is connected to the SPDIF output interface 4. The output connector A4 is the SPDIF output interface 4. The SPDIF output interface 4 is a coaxial interface, using a standard RCA connector and coaxial cable to transmit digital signals; the cable is inexpensive and has good compatibility; however, its anti-interference performance is not as good as that of fiber optic cables. The main control unit 1 uses the MU18 series chip. The waveform shaping logic chip 3 uses the SN74LVC2GU04 chip.

[0023] Example 2

[0024] See Figure 1 , 2 As shown in Figures 3 and 5, this embodiment includes a housing A1, an HDMI connector A2, a circuit board A3, and an output connector A4. The circuit board A3 is disposed inside the housing A1, and the HDMI connector A2 and the output connector A4 are respectively disposed at both ends of the housing A1; the output connector A4 is an RCA interface 9.

[0025] The circuit board A3 includes a main control unit 1, an ARC receiving port 2, an audio receiving chip 6, a digital-to-analog converter chip 7, an operational amplifier chip 8, and an RCA interface 9. The ARC receiving port 2 is connected to a television device via an HDMI connector A2. The input terminal of the audio receiving chip 6 is connected to the ARC receiving port 2. The control terminal of the audio receiving chip 6 is connected to the main control unit 1. The input terminal of the digital-to-analog converter chip 7 is connected to the audio receiving chip 6. The input terminal of the operational amplifier chip 8 is connected to the digital-to-analog converter chip 7. The output terminal of the operational amplifier chip 8 is connected to the RCA interface 9.

[0026] The audio receiver chip 6 is a CS8416. The digital audio receiver chip 6 receives the SPDIF audio signal output from the ARC receiver port 2; converts the SPDIF signal into a standard I2S format audio data stream for output; and outputs it to the subsequent digital-to-analog converter chip 7 for processing via the I2S bus.

[0027] The digital-to-analog converter chip 7 is a PCM4344. The digital-to-analog converter chip 7 receives the I2S digital audio signal output from the digital audio receiver chip 6, converts the I2S digital audio signal into an analog stereo audio signal (left channel L, right channel R); and outputs the analog audio signal to the audio processing and volume amplifier chip 8 for volume control and further processing.

[0028] The operational amplifier chip 8 is selected as PCM8904. The operational amplifier chip 8 is a chip that converts analog audio signals to digital audio (I2S), and can realize the function of acquiring digital audio streams from external analog signals (such as RCA input and output).

[0029] This embodiment is based on HDMI ARC (Audio Return Channel) technology, which aims to convert the digital audio signal output by the TV or host through the HDMI interface into a traditional RCA analog audio signal to adapt to audio systems or amplifiers that do not support digital input.

[0030] After the device is powered on, the main control unit 1 control module first completes the initialization operation and starts HPD detection to determine if a TV is connected. Once the device connection is detected, the main control unit 1 communicates with the TV via the CEC (Consumer Electronics Control) protocol, activates the ARC channel, and establishes an audio transmission link. Subsequently, the TV transmits the audio signal to this device via the HDMI interface in SPDIF protocol format.

[0031] The received SPDIF digital audio signal first enters the SPDIF receiver chip (such as CS8416), which decodes the SPDIF signal into a standard I2S format serial audio signal, including left and right channel data, clock signal, and frame synchronization signal. The decoded I2S audio signal is transmitted to the digital-to-analog converter chip 7, where it is configured under the I2C control of the main control unit 1. The digital-to-analog converter chip 7 converts the I2S signal into analog voltage signals for the left and right channels.

[0032] To improve signal quality and drive subsequent audio equipment, the converted analog audio signal further enters the analog processing module, which is typically a dual-channel buffer amplifier chip with filtering and signal driving functions. Finally, the analog signal processed by the operational amplifier chip 8 is output through the RCA interface and can be directly connected to traditional audio systems, power amplifiers, or active speaker systems to achieve high-fidelity audio playback.

[0033] The above description is only used to illustrate the technical solution of this utility model and is not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solution of this utility model, as long as they do not depart from the spirit and scope of the technical solution of this utility model, should be covered within the scope of the claims of this utility model.

Claims

1. A multi-format output conversion device for audio signals based on ARC, characterized in that: It includes a housing (A1), an HDMI connector (A2), a circuit board (A3), and an output connector (A4). The circuit board (A3) is located inside the housing (A1). The two ends of the housing (A1) are respectively provided with an HDMI connector (A2) and an output connector (A4). The output connector (A4) is an SPDIF output interface (4) or an RCA interface (9).

2. The multi-format output conversion device for ARC audio signals according to claim 1, characterized in that: The circuit board (A3) includes a main control unit (1), an ARC receiving port (2), a waveform shaping logic chip (3), and an SPDIF output interface (4). The ARC receiving port (2) is connected to a television device through an HDMI connector (A2). The TV communicates with the main control unit (1) through the ARC receiving port (2). The audio output of the ARC receiving port (2) is connected to the waveform shaping logic chip (3), and the output of the waveform shaping logic chip (3) is connected to the SPDIF output interface (4).

3. The multi-format output conversion device for ARC audio signals according to claim 1, characterized in that: The output connector (A4) is the SPDIF output interface (4).

4. The multi-format output conversion device for ARC audio signals according to claim 2, characterized in that: The main control unit (1) uses the MU18 series chip.

5. The multi-format output conversion device for ARC audio signals according to claim 2, characterized in that: The waveform shaping logic chip (3) is selected from the SN74LVC2GU04 chip.

6. The multi-format output conversion device for ARC audio signals according to claim 1, characterized in that: The circuit board (A3) includes a main control unit (1), an ARC receiving port (2), an audio receiving chip (6), a digital-to-analog converter chip (7), an operational amplifier chip (8), and an RCA interface (9). The ARC receiving port (2) is connected to a television device via an HDMI connector (A2). The input terminal of the audio receiving chip (6) is connected to the ARC receiving port (2). The control terminal of the audio receiving chip (6) is connected to the main control unit (1). The input terminal of the digital-to-analog converter chip (7) is connected to the audio receiving chip (6). The input terminal of the operational amplifier chip (8) is connected to the digital-to-analog converter chip (7). The output terminal of the operational amplifier chip (8) is connected to the RCA interface (9).

7. The multi-format output conversion device for ARC audio signals according to claim 6, characterized in that: The audio receiver chip (6) is selected as CS8416.

8. The multi-format output conversion device for ARC audio signals according to claim 6, characterized in that: The digital-to-analog converter chip (7) is PCM4344.

9. A multi-format output conversion device for ARC audio signals according to claim 6, characterized in that: The operational amplifier chip (8) is selected as PCM8904.

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