KR19980047452A - Audio signal processing circuit of optical disc player - Google Patents

Abstract

It converts standard format and IIS format audio data to analog signals using only one digital / analog converter, and converts standard format audio data output from DSP and IIS format audio data output from MPEG decoder. And a second switching unit for switching and selectively outputting the oscillation signals of the 16.9344 MHz oscillator and the 11.2896 MHz oscillator and selectively outputting the switching unit. In one case, the first switching unit selects the standard format audio data output from the DSP and inputs it to the digital / analog converter, and the second switching unit inputs the oscillation signal of the 16.9344 MHz oscillator to the digital / analog converter. Voice data of anal Converts and outputs the signal, and when the audio data reproduced on the optical disc is the IIS format, the first switching unit selects the IIS format audio data output from the MPEG decoder and inputs it to the digital / analog converter. In addition, the second switching unit inputs the oscillation signal of the 11.2896MHz oscillator to the digital-to-analog converter to control the conversion and output of IIS format audio data into an analog signal.

Description

Audio signal processing circuit of optical disc player

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio signal processing circuit of an optical disk player for processing audio data of different formats reproduced on an optical disk such as a video CD (Compact Disk) and LD (Laser Disk).

There are two formats of the voice data recorded and reproduced on the optical disk: STANDARD format (256fs) and IIS format (384fs).

Therefore, the reproducing apparatus for reproducing the optical disc can convert both the standard format and the IIS format voice data into analog signals.

1 is a conventional audio signal processing circuit diagram for processing audio data reproduced on an optical disc. As shown therein, a pickup unit 1 for reproducing a signal recorded on an optical disc (not shown) and a DSP (Digital) for processing audio signals of the pickup unit 1 and outputting audio data Signal Processor) 2, a 16.9344 MHz oscillator 3 for outputting an oscillation signal of 16.9344 MHz, and audio data of a standard format system output from the DSP 2 to the oscillation signal of the 16.9344 MHz oscillator 3; A digital-to-analog converter 4 for converting the analog signal to the analog signal, a moving picture enhancement group (MPEG) decoder 5 for outputting audio data output from the DSP 2 in an IIS format, and an 11.2896 MHz oscillation signal. 11.2896MHz oscillator 6 for outputting the digital-to-analog converter 7 for converting the audio data of the IIS format type output from the MPEG decoder 5 into an analog signal according to the oscillation signal of the 11.2896MHz oscillator 6 ) And the digital / analog side Was composed of a switching unit (8) for selectively outputting the output signal of the group (4) (6).

In the conventional audio signal processing circuit configured as described above, when the optical disc is reproduced, the pickup unit 1 emits light to the optical disc, detects the light reflected from the optical disc, and reproduces the predetermined data recorded therein.

The data reproduced by the pickup section 1 is digitally processed by the DSP 2 to output a clock signal, data synchronized with the clock signal, and a channel clock signal indicating the L channel and the R channel.

The reproduction signal output from the DSP 2 is input to the MPEG decoder 5 and decoded.

Here, when the format of the reproduced audio data is the standard format, the DSP 2 processes and outputs the output signal. In the IIS format, the output signal of the DSP 2 is decoded and output by the MPEG decoder 5. .

Here, when it is assumed that the reproduced audio data is a standard format system, the standard format audio data output from the DSP 2 is inputted to the digital-to-analog converter 4, and according to the oscillation signal of the 16.9344 MHz oscillator 3; It is converted into an analog signal and outputted through the switching section 8.

When the reproduced voice data is assumed to be the IIS format system, the IIS format system audio data output from the MPEG decoder 5 is inputted to the digital-to-analog converter 7 to generate an oscillation signal of the 11.2896 MHz oscillator 6. It is converted into an analog signal and outputted through the switching section 8.

These conventional voice signal processing circuits use expensive digital / analog converters (4) and (6), respectively, to convert voice data of standard format and IIS format to be reproduced on an optical disc into analog signals, thereby producing a product. There was an issue rising.

Accordingly, an object of the present invention is to provide a voice signal processing circuit of an optical disc reproducing apparatus that converts voice data in standard format and IIS format into analog signals using only one digital / analog converter.

The audio signal processing circuit of the optical disk reproducing apparatus of the present invention for achieving the above object comprises a first switch for selectively outputting the standard format audio data output from the DSP and the IIS data audio data output from the MPEG decoder. A switching unit and a second switching unit for selectively outputting the oscillating signals of the 16.9344 MHz oscillator as the first oscillator and the 11.2896 MHz oscillator as the second oscillator are selectively output.

When the audio data reproduced on the optical disc is in standard format, the first switching unit selects the standard format audio data output from the DSP and inputs it to the digital-to-analog converter. The second switching unit 16.9344 MHz of the first oscillator. The oscillation signal is input to the digital-to-analog converter to convert and output voice data in standard format into an analog signal.

When the audio data reproduced on the optical disc is in the IIS format, the first switching unit selects the IIS format audio data output from the MPEG decoder and inputs the audio data to the digital-to-analog converter. 11.2896MHz oscillation signal is input to digital / analog converter to convert and output IIS format audio data to analog signal.

1 is a conventional voice signal processing circuit diagram.

2 is a voice signal processing circuit diagram of the present invention.

Explanation of symbols on the main parts of the drawings

11 control unit 12 pickup unit

13: DSP14: MPEG decoder

15: first switching unit 16: buffer

17: 16.9344 MHz oscillator 18: 11.2896 MHz oscillator

19: second switching unit 20: digital to analog converter

Hereinafter, the audio signal processing circuit of the optical disk player according to the present invention will be described in detail with reference to the accompanying drawings of FIG. 2.

2 is a voice signal processing circuit diagram of the present invention. As shown therein, the control unit 11 controls the operation of the audio data processing reproduced on the optical disc, the pick-up unit 12 for reproducing the signal recorded on the optical disc, and the reproduction signal of the pick-up unit 12. Of the DSP 13 for outputting the voice data by outputting the voice data, the MPEG decoder 14 for outputting the voice data output by the DSP 13 in an IIS format, and the DSP 13 and the MPEG decoder 14 A first switching unit 15 for selectively outputting an output signal under the control of the control unit 11, a buffer 16 for buffering and amplifying the output signal of the first switching unit 15, and oscillation of 16.9344 MHz 16.9344 MHz oscillator 17 which is a first oscillator for outputting a signal, 11.2896 MHz oscillator 18 which is a second oscillator for outputting an 11.2896 MHz oscillation signal, and a 16.9344 MHz oscillator 17 under the control of the controller 11. ) And a second switching unit 19 for selectively outputting the oscillation signal of the 11.2896MHz oscillator 18 And digitally converting the audio data passing through the buffer 16 selectively by the first switching unit 15 to an analog signal according to an oscillation signal selectively output by the second switching unit 19. / Analog converter 20.

The audio signal processing circuit of the optical disk player according to the present invention configured as described above has a predetermined function in which the pickup unit 12 emits light to the optical disk, and detects and reflects the light reflected from the optical disk when the optical disk is reproduced. The data will be played back.

The data reproduced by the pickup section 12 is digitally processed by the DSP 13 to output a clock signal, data synchronized with the clock signal, and a channel clock signal indicating the L and R channels.

The reproduction signal output from the DSP 13 is input to the MPEG decoder 14 and decoded.

Here, when the format of the reproduced audio data is the standard format, the DSP 13 processes and outputs it. In the case of the IIS format, the output signal of the DSP 13 is decoded and output by the MPEG decoder 14. .

Here, when it is assumed that the reproduced voice data is a standard format system, the control unit 11 controls the first switching unit 15 to selectively output the standard format audio data output from the DSP 2. The second switching unit 19 is controlled to selectively output the oscillation signal of the 16.9344 MHz oscillator 17.

Then, the standard format audio data output from the DSP 13 is buffered and amplified in the buffer 16 through the first switching unit 15 and then input to the digital-to-analog converter 20 and the first oscillator. The oscillation signal of the 16.9344 MHz oscillator 17 is input to the digital-to-analog converter 20 through the second switching unit 19.

Therefore, the digital-to-analog converter 20 converts the audio data of the standard format system output from the DSP 13 into an analog signal according to the oscillation signal of the 16.9344 MHz oscillator 17 and outputs the analog signal.

If it is assumed that the reproduced voice data is an IIS format system, the control unit 11 controls the first switching unit 15 to selectively output the IIS format system audio data output from the MPEG decoder 14. The second switching unit 19 is controlled to selectively output the oscillation signal of the 11.2896 MHz oscillator 18 which is the second oscillator.

Then, the IIS format audio data output from the MPEG decoder 14 is buffered and amplified in the buffer 16 through the first switching unit 15 and input to the digital-to-analog converter 20 and 11.2896 MHz. The oscillation signal of the oscillator 18 is input to the digital-to-analog converter 20 through the second switching unit 19.

Therefore, the digital-to-analog converter 20 converts the IIS format audio data output from the MPEG decoder 14 into an analog signal according to the oscillation signal of the 11.2896 MHz oscillator 18 and outputs the analog signal.

As described above, the present invention can reduce the production cost of a product by converting and outputting a standard format voice signal and an IIS format voice signal to an analog signal using only one expensive digital / analog converter.

Claims (3)

A control unit for controlling the processing of the audio data reproduced on the optical disc, a DSP for processing the reproduction signal of the pickup unit for reproducing the signal recorded on the optical disc, and outputting the audio data; and an MPEG for processing the audio data output by the DSP. A first switching unit for selectively outputting a decoder, output signals of the DSP and MPEG decoders under the control of the controller, and a selectively outputting oscillation signals of the first oscillator and the second oscillator under the control of the controller; And a second switching unit and a digital / analog converter for selectively outputting the first data by converting the audio data into an analog signal according to the oscillation signal selectively output by the second switching unit. Voice signal processing circuit of equipment. The optical disc reproducing apparatus according to claim 1, wherein the control unit controls the second switching unit to selectively output the 16.9344 MHz oscillation signal generated by the first oscillator when the first switching unit selectively outputs the voice data of the DSP. Voice signal processing circuit of equipment. The optical disc of claim 1, wherein the control unit controls the second switching unit to selectively output the 11.2896 MHz oscillation signal generated by the second oscillator when the first switching unit selectively outputs the audio data of the MPEG decoder. Audio signal processing circuit of a playback device.