KR200225067Y1 - Multi-channel audio playback device for PC - Google Patents

Abstract

[Purpose] Provision of multi-channel audio playback device for PC

[Configuration] Combines Dolby Digital (AC-3) and Digital Theater System (DTS) decoder functions with a sound card, a two-channel audio playback device for PCs mounted on the PCI bus, to enable multi-channel (5.1-channel) audio playback. It is designed to be used as a digital versatile disk player and audio receiver.

Description

Multi-channel audio playback device for PC {.}

The present invention implements a new multi-channel audio playback device for a PC, and more particularly relates to a digital versatile disk, which is a next generation sound and image medium for providing high quality images and sound.

Currently, the recording method used in DVD can be classified into four categories. Dolby Pro Logic recording used in the absence of a decoder or elsewhere, and new recording methods such as Dolby Digital (AC-3), Digital Theater System, THX, etc. It is designed to provide the best sound.

However, in the conventional sound card for a PC, four channels of four speakers are used to represent a positioning three-dimensional sound, or to compress four channels to support DVD stereo sound, and to reproduce four channels or to output an external digital output. The reality is that it provides only a degree.

As a result, no sound card supports all 5.1 channels of DVD, and perfect DVD viewing on a PC is impossible.

The present invention particularly provides a multi-channel playback device for a PC that is mounted and operated on the PCI bus, to implement a high quality surround sound in a general computer by incorporating the AC-3 and DTS decoder function in the sound card function of a general PC will be. In particular, the software controls the functions of Wave, MIDI, MP3 player, etc., and can be used as a PC DVD player and A / V receiver (Audio / Video receiver).

1 is a block diagram for explaining the present invention,

2 (a) and 2 (b) are main circuit diagrams for explaining the present invention.

In the drawings, reference numeral 1 is an analog signal input, 2 is an AC-97 PCI audio codec, 3 is an analog output, 4 is a 6-channel digital-to-analog converter, 5 is a multi-channel configuration playback decoder processor, 6 is a digital audio receiver, 7 is S / PDIF input / output, 8 is PCI audio accelerator processor, 9 is MIDI input / output, 10 is game joystick output, 11 is PCI BUS, 12 is power supply, 13 is audio power amplifier, U1 is PCI An audio accelerator processor, U2 is an AC-97 PCI audio codec, U3 is a digital audio receiver, U4 is a multi-channel configuration playback decoder processor, U5 is a six-channel digital-to-analog converter, and U7 is a constant voltage IC.

When the present invention is described in detail according to the accompanying drawings as follows. 1 is a block diagram for explaining the present invention, the analog input unit 1 (ANALOG INPUT), the auxiliary left / right input unit (AUX R / L INPUT) and the compact disc left / right input unit (CD R / L INPUT) and line left The signal input from the LINE R / L INPUT and MIC R / L INPUT is output via the 4-channel AC-97 CODEC (2) (4-CHANNEL AUDIO CODEC 97). The output unit 3 outputs the line left / right output unit LINE R / L OUT and the 6-channel audio output unit 6-CHANNEL AUDIO OUT, together with the 6-channel digital analog converter 4 (6-). CHANNEL DAC) and the AC-3, DTS multi-channel decoder 5 (DOLBY DIGITAL / DTS DECODER + SUB DSP), and the output is sent to a 24-bit digital audio receiver 6 (24 BIT DIGITAL AUDIO RECEIVER). . The receiver 6 has an input / output unit 9 (MIDI IN / 0UT) and a game joystick signal for controlling an electronic musical instrument by a computer by a PCI audio accelerator (8) (DSP: Digital Signal Processor) is synthesized to be mixed with the output signal of the 4-channel AC-97 (2) described above and sent to the 24-bit digital audio receiver (6). 1 to 7 is a S / PDIF (Sony Philips Digital Interface) input / output unit, 11 is a PCI BUS, 12 means a power supply (POWER) for supplying the operating power to each of the circuits described above.

2 (a) (b) (c) is a detailed circuit diagram of an embodiment for explaining the main part of the present invention, the symbol J1 in the drawing is a PCI slot to be equipped with a sound card, designed to operate at 32Bit, 33Mhz, the main Since 3.3V is not supported depending on the board specification, 3.3V is supplied using the constant voltage IC (U7).

In the figure, U1 is a PCI audio accelerator, which is an IC that is responsible for the main DSP that handles the main processing of the PC sound card. It receives data from 32Bit bus of PCI interface through the software which is in charge of main processing of PC sound card, and controls the AC-97 CODEC (2) and S / PDIF Input / Output. It is supposed to perform the acceleration function. In addition, the integrated circuit consisting of 420MIPS high-performance digital signal processor is used to reduce the processing burden of the audio function from the PC's control processing unit (CPU) .This enables the hardware to perform Direct Sound 3D, EAX, Sensaura 3D functions perfectly in hardware. It is. Meanwhile, U2, an AC-97 codec, converts the digital audio stream transmitted from the main DSP U1 into an analog signal, and converts analog signals such as a microphone and a line input / output into a digital stream. It is.

In the encoder U2, the digital processing DSP and the analog processing codec have separate functions in separate integrated circuits to minimize the influence of digital noise.

U3 is a digital interface receiver (DIR) that converts and transmits the digital audio stream transmitted from the outside of the PC or from the main DSP (U1) to the AC-3, DTS, and decoder DSP (U4). It is also responsible for generating the operation clock of the 6-channel audio DAC according to the sample rate of the circuit. On the other hand, it is possible to select internal or external S / PDIF signal by software.

The audio decoder DSP U4 analyzes the audio stream transmitted from the DIR U3, decodes the AC-3 and DTS signals, and transmits the decoded audio data to the six-channel DAC U5. In addition, this IC with dual DSP structure has two 25MIPS DSPs, which are divided into main DSP and sub DSP. The main DSP is used to decode AC-3 and DTS, and to control Sub DSP and software. This allows you to do various field processing (Field Processing: Hall, Concert ...).

The decoder U5, which is a six-channel DAC, converts audio data transmitted from the DSP U4 into an analog signal and operates in synchronization with a clock generated by a DIR (Digital Interface Receiver). Functions such as volume and mute are controlled by the PC software by the main DSP U1.

The power circuit is supplied with 5V and 12V from PCI SLOT, and 3.3V is supplied by LDO (Low Drop Out) constant voltage IC (U7). PC Power Management All ICs used to support Advanced Configuration and Power Interface (ACPI) and Advanced Power Management (APM) have a power down function and are controlled by the main DSP and the PC's OS.

In addition, all ICs are connected to the main DSP (U1) by SPI (Serial Peripheral Interface) communication to transfer control signals and operation status, and the PC's OS and application software control the main DSP (U1) to perform all functions. have.

The operation of the configuration as described above is as follows.

That is, 5V is converted into 3.3V using constant voltage IC (U7) on B54 pin of PCI SLOT (J1) to supply power. The PCI Audio Accelerator (U1) is the main DSP that handles the computer's sound card, and the data is sent to the PCI interface through the software built-in. The AC-97 CODEC (U2) is the 96, 99 It is possible to control the clock with pin #, reset the AC-97 codec with pin # 100, send and receive data with pins 97 and 98, and the S / PDIF input / output unit connects pins 83 and 84 of the U2. It is responsible for sending and receiving data, and performs the hardware acceleration function required by the computer. Therefore, to reduce the processing burden of audio functions from the computer's CPU, the Direct Sound 3D, EAX, and Sensaura 3D functions are completely implemented in hardware using ICs composed of high performance DSP of 420MIPS.

Meanwhile, the AC-97 CODEC (U2) converts the digital audio stream transmitted from the PCI audio accelerator U1 into an analog signal and outputs it to pins 5 and 8, and the microphone and line input / output units are 21, 23, It converts the analog signal coming through pin 24 into a digital stream. Therefore, the digital processing DSP and the analog processing codec can separate the digital and analog functions into separate ICs to minimize the effects of digital noise.

The digital audio receiver (U3) selects the chip with the 25th pin and controls the 26th clock, and sends and receives the data with the 27th and 28th pins of the digital audio stream transmitted from the computer or the main DSP. It converts the signal to the DTS decoder DSP (U4) and transmits it, and plays the role of generating the operation clock of the 6 channel audio DAC on pins 19, 20 and 21 according to the sample rate of the input signal.

The audio decoder DSP (U4) decodes the AC-3, DTS, and Pro-Logic signals by separating the data transmission to pin 84 by controlling the clock on the audio stream transmitted from DIR (U3) to pins 82 and 83. The decoded audio data is transmitted to pins 45, 46 and 47 of the 6-channel DAC (U5). With dual DSP structure, this IC has two 25MIPS DSPs, so the main DSP can decode AC-3 and DTS, and the sub DSP can perform various field processing by software control. will be.

The 6-channel DAC (U5) receives the digitized audio data transmitted from the decoder DSP through pins 13, 14, and 15 and converts it into an analog signal.The clock generated by the digital audio receiver DIR (U3) is 9, 10, It is operated by input on pin 16, volume and mute control by main DSP (U1) is performed by pins 9 and 16, and it has high performance of 24bit 96Khz, 112dB required by AC-3 and DTS. You can do this by using an audio DAC.

As described above, according to the present invention, since a high performance multi-channel audio (AC-3, DTS) decoder function that is not possible with a conventional sound card can be performed, it is possible to use a PC DVD drive and an embodiment of the present invention. PC DVD systems can be provided, and the high-quality sound (24Bit, 96kHz, 110dB) that can not be heard in the existing sound card can be used in the PC to use the functions provided by expensive A / V equipment. As described above, the present invention relates to an AC-3 and a DTS decoder implemented in a PC, and the connection technology of the sound card and the decoder hardware will use the same technology as the new embodiments in the future. .

Claims (2)

In the computer multi-channel audio playback device mounted on the PCI bus, the SLOT (J1) and the PCI audio accelerator (U1) to be equipped with a sound card to perform the hardware acceleration function required by the computer, The AC-97 CODEC (U2) converts the digital audio stream transmitted from the PCI audio accelerator (U1) into an analog signal, and converts the analog signal input through the microphone and line input / output into a digital signal. The digital audio receiver U3 converts and transmits a digital audio stream transmitted from an external computer or a main DSP to a Dolby Digital (AC-3) and DTS decoder DSP. The six-channel audio DAC depends on the sample rate of the input signal. Generate an operating clock of The audio decoder DSP U4 transmits the decoded audio data to the six channel DAC U5 according to the audio streams AC-3 and DTS transmitted from the DIR U3. The six-channel DAC converts digitized audio data transmitted from the decoder DSP into an analog signal and controls volume and mute by the main DSP (U1). The method according to claim 1, All integrated circuits are connected to the main DSP by SPI communication to transfer control signals and operating status, and the PC's OS and application software control the main DSP.