KR100768847B1 - High speed read/write apparatus - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high speed reproduction / recording apparatus, and in the related art, the frequency of the recording clock becomes very high as the speed increases, which affects the operational stability inside the front-end DSP chip, thereby operating stability of the entire optical recording / reproducing apparatus. There was a problem of lowering. In view of the above problems, the present invention provides an apparatus comprising: an NRZI pattern analyzer for analyzing a pattern of marks and spaces of NRZI to be recorded on an optical disk; A time parameter calculator for calculating a time parameter for a recording pulse for the mark of the NRZI; A write pulse generator for generating a write pulse in accordance with the calculated time parameter; A first and second pulse timing adjusters for adjusting the timing of the generated write pulses to produce a write pulse signal in the reproduction / recording system of an optical disc such as a CD / DVD / BD. By presenting a method of using a clock of frequency, it provides the stability of the DSP chip operation and performance even at high speed recording, thereby achieving the operation and performance stability of the entire optical disc playback / recording system.

Description

High speed playback / recording device {HIGH SPEED READ / WRITE APPARATUS}

1 is a block diagram showing the structure of a conventional optical recording and reproducing apparatus.

FIG. 2 is an exemplary view showing timing of an NRZI and a write pulse of FIG. 1. FIG.

3 is a block diagram showing the configuration of a high speed reproduction / recording apparatus of the optical recording / reproducing apparatus according to the embodiment of the present invention;

4 is a timing diagram of a write pulse signal output from the front-end DSP chip of FIG.

5 is a timing diagram between a parameter of a recording pulse signal and NRZI.

6 is a timing diagram illustrating generation of a write pulse signal using a 1/2 frequency clock according to an embodiment of the present invention.

7 is a block diagram showing a configuration of a recording pulse signal generating apparatus having two frequency domains in a high speed reproduction / recording apparatus according to an embodiment of the present invention.

** Description of the symbols for the main parts of the drawings **

101: NRZI pattern analyzer 102: time parameter calculator

103: recording pulse generator 104: first pulse timing regulator

105: second pulse timing regulator 106: microcomputer interface

107: light strategy

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high speed playback / recording apparatus, and in particular, that is required for accurate recording in a reproduction / recording system of an optical disc such as a Digital Versatile Disc (DVD) / Blu-ray Disc (BD). A high speed reproduction / recording apparatus which makes it possible to generate a recording pulse for high speed recording in the generation of various types of recording pulses.

Blu-ray Disc is a new standard for large-capacity optical discs developed as the next generation DVD in the digital broadcasting era. While the current DVD uses a red laser with a wavelength of 650 nanometers as a light source, the newly developed next generation DVD has a blue violet color with a wavelength of 405 nanometers. By using a laser, it has a recording capacity of about five times (23 gigabytes on one side). By multilayering the recording layer, tera (one set) optical disk technology has also been developed.

A system for reproducing data recorded on an optical disc or recording data on an optical disc is called a high speed reproduction / recording device. The high speed reproduction / recording device rotates the optical disc by controlling a servo motor for rotating the optical disc at high speed. The high speed reproduction / recording device reproduces data recorded on a rotating optical disc or records data on a rotating optical disc. When the servo motor is stabilized and rotates at high speed, the high speed reproduction / recording device samples and holds a wobble signal having an disc information and an address, thereby important information during reproduction / recording. Used as (information).

In general, the accurate recording of optical discs in high speed playback / recording devices determines the performance of the overall system. As the higher speed increases, the difficulty of accurate recording of the optical disc becomes more and more, and the light strategy implementation that generates the recording pulse in the high speed playback / recording device is in a very important position that determines the performance of the entire system. An example of the high speed reproduction / recording apparatus belongs to the optical recording / reproducing apparatus.

1 is a block diagram showing the structure of a conventional optical recording and reproducing apparatus. The optical recording / reproducing apparatus is composed of the front end DSP chip 16, the RF chip 13, the microcomputer 14, the Y pyrom 15, the pickup 12, and the optical disk 11. The write strategy of the front end DSP chip 16 outputs a recording pulse to the pick-up 12, and the pickup 12 receives the recording pulse and is included in the recording pulse on the optical disc 11. Record the data.

In the front end DSP chip 16 the write pulse is generated from several parameter values. The various parameter values of the write pulse are based on a certain point in time of the mark and space of Non-Return to Zero Inverting (NRZI) and usually have a resolution of 1 / 32T. (1T is one cycle of the write clock.)

The recording pulse is an element that determines whether the optical disk 11 is correctly recorded, and has a multi pulse and a non-multi pulse. Among these, the difficulty of the multi-pulse implementation is higher, and the higher the speed, the more difficult the difficulty is.

FIG. 2 is an exemplary view showing timing of an NRZI and a write pulse of FIG. 1. When the width of the multi-pulse goes to a high double speed, it is characterized by appearing over 2T within the existing 1T, which can be attributed to the very short time corresponding to 1T at high double speed.

At higher speeds, the frequency of the recording clock becomes very high, which affects the operational stability inside the front-end DSP chip 16, resulting in a deterioration of the operational stability of the entire optical recording and reproducing apparatus. Specifically, at DVD 16x, the recording clock reaches 416 MHz (26 MHz X 16), and this high-frequency clock inside the front-end DSP chip 16 acts as a source of noise, resulting in other blocks. Blocks have a number of negative impacts, especially the possibility of malfunction of analog blocks. This directly affects the operational stability of the front-end DSP chip 16, which affects the operational stability of the overall system. In addition, significant overhead is incurred in designing the chip into a block that uses a high frequency clock, resulting in an increase in the cost of the overall system.

Therefore, we propose a method of implementing write strategy for high-speed recording at a low recording clock frequency to ensure the stability of the front-end DSP chip 16 operation and performance, and to improve the operation and performance stability of the entire optical disc playback / recording system. It is also required to pursue the cost savings of the entire system.

Accordingly, the present invention has been made in view of the above problems, and it is possible to generate an accurate recording pulse signal at a low recording clock frequency for stable operation and performance of an optical disk reproducing / recording system such as a CD / DVD / BD. It is an object of the present invention to provide a high speed reproduction / recording device.

The present invention for achieving the above object is an NRZI pattern analyzer for analyzing the pattern of the mark and space of the NRZI to be recorded on the optical disk; A time parameter calculator for calculating a time parameter for a recording pulse for the mark of the NRZI; A write pulse generator for generating a write pulse in accordance with the calculated time parameter; First and second pulse timing adjusters for adjusting the timing of the generated write pulses, wherein the operating clock frequencies of the NRZI pattern analyzer and the time parameter calculator correspond to minimum units of the mark and space of the NRZI. And a clock frequency obtained by converting a recording clock frequency by double speed, and an operating clock frequency of the recording pulse generator and the pulse timing regulator is a clock frequency obtained by converting a recording clock frequency by double speed to correspond to the minimum unit of the mark of the NRZI. do.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram showing the configuration of a high speed reproduction / recording apparatus of the optical recording / reproducing apparatus according to the embodiment of the present invention.

The optical recording and reproducing apparatus is designed to lower the frequency of the operation clock required for generating the recording pulse in generating the recording pulse for the stable operation of the high speed reproduction / recording apparatus.

The optical recording / reproducing apparatus includes an NRZI pattern analyzer 101 for analyzing a pattern of marks and spaces of NRZI to be recorded on an optical disk; A time parameter calculator (102) for calculating a time parameter for a recording pulse for the mark of the NRZI; A write pulse generator (103) for generating a write pulse in accordance with the calculated time parameter; And first and second pulse timing adjusters 104 and 105 for adjusting the timing of the generated write pulses.

The optical recording / reproducing apparatus generates a recording pulse by using a clock frequency corresponding to 1/2 frequency or 1/4 frequency of the recording clock frequency for each recording speed corresponding to the time parameter of the recording pulse.

The parameters are given in units of mark and space of NRZI, and in consideration of the characteristic that the minimum unit of mark and space is 4T, the NRZI pattern analyzer 101 and the time parameter calculator 102 have a quarter frequency of the recording clock frequency for each double speed. Use the clock as the operating clock.

The recording pulse is generated from the mark, and in consideration of the characteristic that the minimum unit of the mark is 2T, the recording pulse generator 103 and the pulse timing adjusters 104 and 105 operate the clock at 1/2 frequency of the recording clock frequency for each double speed. Used as

The write pulse generator 103 converts and provides parameter values based on the falling edge of the clock in the time parameter calculator 102 so as to generate a write pulse based on the rising edge of the operating clock. Since the write pulse generator 103 uses a clock of a frequency 1/2 of the write clock frequency for each double speed as an operation clock, the clock edge reference of the parameter changes from time to time according to the NRZI pattern.

The optical recording and reproducing apparatus lowers the frequency of the operation clock required for generating the recording pulses to enable high speed recording at a low clock frequency, thereby providing DSP chip operation and performance stability at high speed recording, and further, operation and performance stability of the entire system. do.

4 is a timing diagram of a write pulse signal output from the front-end DSP chip of FIG. 3, FIG. 5 is a timing diagram between a parameter of the write pulse signal and NRZI. 6 is a timing diagram illustrating generation of a recording pulse signal using a 1/2 frequency clock according to an exemplary embodiment of the present invention, and FIG. 7 illustrates two frequency regions in a high speed reproduction / recording apparatus according to an exemplary embodiment of the present invention. It is a block diagram which shows the structure of the recording pulse signal generation apparatus provided.

An optical recording and reproducing apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

The terms used in the present invention are defined.

The write pulse used in the present invention is generated corresponding to the NRZI signal on the basis of a reference clock of a predetermined period. The NRZI signal includes a mark and a space of nT length (for example, 2 to 8T). When the NRZI signal corresponds to a mark having a length of 2T, a recording pulse composed of a corresponding leading edge (2LE), a front pulse (2FP) and a tailing edge (2TE) is generated. When the NRZI signal corresponds to a mark having a length of 3T, a recording consisting of a leading edge 3LE, a front pulse 3FP and a last pulse 3LP, and a tailing edge 3TE corresponding thereto Pulse is generated.

When the NRZI signal corresponds to a mark having a length of 4T to 8T, the recording pulse includes leading edges 4 to 8LE, front pulses 4 to 8FP, and multi pulses 4 to 8MP: 4 corresponding to the NRZI signal. ~ 8 Multi Pulse), last pulse (4 ~ 8LP: 4 ~ 8 Last Pulse), and tailing edge (4 ~ 8TE).

The multi-pulse controls the mark shape, and the mark is an amorphous region in the crystalline space region. The operating clock is the reference clock required for the generation of the write pulses.

TSFP is a timing start front pulse, TEFP is a timing end front pulse, TSMP is a timing shift multi pulse, TEMP is a timing end multi pulse, TSLP is a timing start last pulse, TCLP is a timing cooling last pulse, and BD is Blu-ray Disc, Light Strategy is a recording strategy.

4 is a timing diagram of a recording pulse signal output from a front-end DSP chip.

The write pulse signal is generated from parameter values with reference to a certain point in time of the NRZI mark / space. The recording pulse signal is generated in the mark / space section, and the main generation section is the mark section. In the generation of a recording pulse, that is, a multi-pulse signal, it is divided into a first pulse, a middle multi pulse, a last pulse, and a cooling pulse. There are two parameters indicating the start and the end of each pulse, and the parameters are given differently for each pulse. In particular, the middle pulse is repeated in multiple pulses and appears over 2T as it goes at high speed. The details of each parameter are as follows. The first pulse related parameters TSFP (Timing Start Front Pulse) and TEFP (Timing End Front Pulse) vary in value depending on the combination of previous space and current mark length. The middle pulse related parameters TSMP (Timing Shift Multi-Pulse) and TEMP (Timing End Multi-Pulse) vary in value only by the current mark length. Last pulse related parameters TSLP (Timing Start Last Pulse) and TELP (Timing End Last Pulse) are given different values according to the current mark and next space length combination. The cooling pulse related parameter TCLP (Timing Cooling Last Pulse) is also given a value according to the current mark and the next space length combination. Therefore, the NRZI pattern analyzer analyzes the mark / space length combination in advance.

5 is a timing diagram between a parameter of a write pulse signal and NRZI. The timing diagram indicates an effective section of the parameters of the write pulse. In general, since the timing of the start and end of the recording pulse is changed in units of (mark + space) of the NRZI, the parameters of the recording pulse are also changed in units of (mark + space) of the NRZI. The minimum (mark + space) unit is 4T since (2T + 2T) exists in the BD. Accordingly, the clock frequency of the write strategy front end blocks 101 and 102 may be lowered to 1/4 of the write clock frequency for each double speed to operate. That is, the NRZI pattern analyzer accepts 4 bit NRZI data per clock cycle to analyze the pattern. Since the NRZI data in (mark + space) unit is 4 bits or more, parameters can be provided without loss.

6 is a timing diagram illustrating generation of a write pulse signal using a 1/2 frequency clock according to an embodiment of the present invention. The timing diagram illustrates the timing of the write pulses relative to the half frequency clock in the write pulse generator 103. Since the minimum unit of each write pulse in generating the write pulse is 2T, the clock frequency of the middle and trailing blocks 103, 104 and 105 of the write strategy can be lowered to 1/2 of the write clock frequency for each double speed. have. 6 shows that each pulse is properly generated at a 1/2 frequency clock. Looking closely at Figure 6, the first & cooling pulses are given the parameters correctly relative to the rising edge of the 1/2 frequency clock, while the middle & last pulses are given relative to the falling edge. Since write pulses are generated on the rising edge of the clock, the parameter values of the falling edge should be changed on the rising edge. That is, it is necessary to increase 0.5T more than the half frequency clock, and by performing this in the time parameter calculator 102, it is possible to generate an accurate multi-pulse in the recording pulse generator 103.

7 is a block diagram showing the configuration of a recording pulse signal generating apparatus having two frequency domains in a high speed reproduction / recording apparatus according to an embodiment of the present invention. The recording pulse signal generating apparatus divides two frequency regions, which are regions using a quarter frequency clock or a half frequency clock, to provide a frequency clock suitable for a block necessary for generating a recording pulse signal. In the NRZI pattern analyzer 101 and the time parameter calculator 102 using the 1/4 frequency clock, NRZI data is received by 4 bits, the pattern is analyzed, and the parameters are converted and provided to the recording pulse generator 103, thereby providing a write pulse generator ( In 103, a write pulse is generated based on the rising edge of the 1/2 frequency clock. In other words, by enabling high speed recording at a low clock frequency, the DSP chip operation and performance stability at high speed recording can be further provided to provide operation and performance stability of the entire optical disc reproducing / recording system. On the other hand, since the additional hardware cost of each block is low, it is not a big burden in terms of hardware cost.

In the above, the high speed reproduction / recording apparatus having the above configuration is configured to analyze the mark of the NRZI and the space pattern to be recorded on the optical disk by the NRZI pattern analyzer, and the time parameter calculator to time parameters for the recording pulses for the marks of the NRZI. Configure a write pulse generator, generate a write pulse according to the calculated time parameter, and configure first and second pulse timing adjusters to adjust the timing of the generated write pulse. That is, the high speed reproduction / recording device may be implemented by different device configurations, but may be implemented by combining or subdividing the device configurations as necessary.

In addition, the high speed reproduction / recording apparatus may be implemented by a processor such as a microcontroller capable of executing a program for performing a series of procedures. For example, the microcontroller includes a parameter calculation interface for analyzing a pattern of NRZI to calculate a time parameter for a write pulse, a write pulse interface for generating a write pulse, and a timing interface for adjusting the timing of the generated write pulse. can do.

The processor may apply differently the parameter calculation interface, the write pulse interface, and the timing interface. The recording pulse interface may generate a recording pulse using a clock frequency corresponding to 1/2 frequency or 1/4 frequency of the recording clock frequency for each recording speed corresponding to the time parameter of the recording pulse. In consideration of the characteristic that the minimum unit of mark and space is 4T, the clock of 1/4 frequency of the recording clock frequency by double speed is used as the operation clock, and the timing interface is the recording clock by double speed considering the characteristic that the minimum unit of mark is 2T It can be applied to use the clock of frequency 1/2 of the frequency as the operation clock.

As described in detail above, the present invention provides a method of using a low frequency clock in a write strategy block in generating a recording pulse signal in a reproduction / recording system of an optical disc such as a CD / DVD / BD. The double speed recording also provides the stability of the DSP chip operation and performance, thereby achieving the operation and performance stability of the entire optical disc playback / recording system.

In addition, the present invention implements a DSP chip suitable for a high speed playback / recording apparatus using a low frequency clock, thereby reducing the overhead incurred when implementing the chip, thereby preventing cost reduction and reducing the overall system cost. In addition, the use of a lower frequency clock during writing also has the effect of reducing the DSP chip's operating time and thus reducing the overall power consumption.

Claims (5)

An NRZI pattern analyzer for analyzing patterns of marks and spaces of NRZI to be recorded on the optical disk; A time parameter calculator for calculating a time parameter for a recording pulse for the mark of the NRZI; A write pulse generator for generating a write pulse in accordance with the calculated time parameter; A first and second pulse timing adjuster for adjusting the timing of the generated write pulse, Here, an operating clock frequency of the NRZI pattern analyzer and the time parameter calculator is a clock frequency obtained by converting a recording clock frequency for each double speed to correspond to the minimum unit of the mark and space of the NRZI, And an operating clock frequency of the recording pulse generator and the pulse timing adjuster is a clock frequency obtained by converting a recording clock frequency for each double speed to correspond to the minimum unit of the mark of the NRZI. The method of claim 1, The recording pulse generator High-speed reproduction / recording, characterized in that for generating a recording pulse using a clock frequency corresponding to 1/2 clock frequency or 1/4 clock frequency of the recording clock speed for each recording speed corresponding to the time parameter of the recording pulse. Device. The method of claim 1, When the minimum unit of the mark and space of the NRZI is 4T, the operating clock frequency of the NRZI pattern analyzer and the time parameter calculator converted to correspond to the minimum unit is 1/4 clock frequency of the recording clock frequency for each double speed. A high speed playback / recording device characterized by the above-mentioned. The method of claim 1, When the minimum unit of the mark of the NRZI is 2T, the operating clock frequency of the recording pulse generator and the pulse timing regulator converted to correspond to the minimum unit is 1/2 clock frequency of the recording clock frequency for each double speed. High speed playback / recording device. The method of claim 1, wherein the time parameter calculator A high speed reproduction / recording device, characterized in that it is configured to convert parameter values with respect to the falling edge of a clock and provide them to a recording pulse generator.

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