KR970002939Y1 - Tracking error check circuit of disk player - Google Patents

Abstract

None.

Description

Disc player tracking device

1 is a circuit diagram of a tracking error prevention device of a disc player as a preferred embodiment of the present invention.

2 is a diagram illustrating waveforms of the main part of FIG. 1.

* Explanation of symbols for main parts of the drawings

10: Trek error signal input terminal 30: Filtering unit

31, 32: low pass filter 40: track deviation check

41: upper limit reference value comparison unit 42: lower limit reference value comparison unit

43: ora gate 50: control unit

VR _1, VR ₂ : Variable resistor OP _1: Buffer

OP _2, OP ₃ : Comparator

The present invention relates to a tracking error prevention device of a disc player, and more particularly, to a tracking error prevention device of a disc player for monitoring, comparing and correcting whether a recording pickup device caused by an external impact or noise source is disengaged from a normal position on a track. It is about.

In general, a magneto-optical disc player is a new sound device that can be recorded and reproduced using a CD-like technique, unlike a device for reproducing only already recorded music signals, like a conventional compact disc player (hereinafter referred to as a CD). .

The operation principle is briefly described. The magneto-optical disk has a reflective layer and a recording layer at the same time. If the temperature of the recording layer on the spiral track is raised by a certain point using a laser and a lens, the magnetic field is formed externally. Even after the magnetic field is removed, residual magnetic fields exist in the same direction, so that digital recording is possible.

Thereafter, during reproduction, digital reproduction is possible using the principle that the polarization angle shift of the reflection polarization of the reflection layer is different depending on the direction of the magnetic field of the recording layer.

Therefore, when recording, the sound of the playback device may be different from the original sound when RUN OUT occurs due to an external shock or noise. There is a large imbalance phenomenon, and the conventional techniques for solving the above problems have a long delay time to the comparison decision when the track of the pick-up device is out of track, resulting in a large loss of data and a built-in circuit in the IC. There is a problem that it is difficult to set the precise reference value because it is impossible to change the device.

The object of the present invention to solve the problems of the prior art as described above is to set a safe threshold for recording and playback even if the pickup device is out of the track center, and detects the error amount of the track and compares it with the detected error amount of the track. It is an object of the present invention to provide a tracking error prevention device for a disc player that can stop recording and re-record the portion again when the amount of error exceeds a threshold, thereby enabling more accurate storage and recording of data.

A feature of the present invention for achieving the above object is that the track error signal generation means for generating a track error signal and the track deviation of the pickup device in the disc player having a pickup means for recording and playing data on the track A tracking error prevention device of a disc player for monitoring and correcting, comprising: an input means for receiving a track error signal, a low pass filtering means for removing an RF signal mixed with a track error signal applied from the input means, and the filtering And track control means for determining whether or not there is a track deviation of the pickup apparatus by receiving the track error signal, and control means for determining whether to correct an error by receiving a signal output from the track deviation check.

In addition, another feature of the present invention is to further include a buffer provided between the input means and the low pass filtering means so as not to affect other devices using the track error signal.

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

1 is a circuit configuration diagram of a tracking error prevention device of a disc player as a preferred embodiment of the present invention.

The structure of the present invention is largely a track error signal input terminal 10, a buffer (OP ₁ ) that is applied to the non-inverting input terminal voltage terminal and the signal output from the input terminal 10 is applied again to the inverting input terminal, and A low pass filtering unit 30 for detecting only a pure track error signal by receiving the output signal of the buffer OP ₁ and a stable limit value of a track set by receiving the output signal of the low pass filtering unit 30. The track departure check unit 40 and the track departure check unit 40 are configured to receive an output signal and determine whether or not to rewrite.

And the second resistor (R ₂₎ connected to the output of the low pass filter portion (30) of the can and the first resistor (R ₁₎ who is the output signal of the buffer (OP1), the first resistor (R _1), The first capacitor C ₁ connected between the output terminal of the first resistor R ₁ and the ground g, and the second capacitor connected between the output terminal of the second resistor R ₂ and the ground G, respectively. It consists of a capacitor C ₂ .

In addition, the track deviation checker 40 receives the third resistor R ₃ receiving the constant voltage (+ Vcc) and the output signal of the low pass filtering part 30 to the non-inverting input terminal, resistance (R ₃₎ a first comparator receiving applied to the inverting input a signal of the output terminal (OP ₂₎ and the first comparator a first variable resistor connected between the inverting input and ground (G) of (OP ₂₎ (VR ₁ A track upper limit detection unit 41, a fourth resistor VR _{4 that} receives a predetermined voltage (-Vcc), and an output signal of the low pass filtering unit 30 are applied to an inverting input terminal to receive the fourth resistor VR. a second comparator (OP ₃₎ and a second comparator (OP ₃₎ a second variable resistor (VR ₂₎ which is connected between the non-input terminal and the ground (G) of the signal of the output stage to receive applied to the non-inverting input terminal of the ₄₎ The track lower limit detection section 42 and an oragate 43 for inputting the output signal of the first comparator OP ₂ and the output signal of the second comparator OP ₃ . It is broken.

With reference to the waveform example of FIG. 2, the preferable operation example of this invention comprised as mentioned above is demonstrated.

2 is an exemplary waveform diagram of the main part of FIG. An input terminal (10) the track error signal (second-degree A) to be applied to is applied to the non-inverting input terminal of the buffer (OP ₁₎ is output to the output terminal of the buffer (OP _1).

The first low pass filtering unit 31 receiving the output signal of the buffer OP ₁ first removes the high frequency component and then applies the second low pass filtering unit 32 to the second low pass filtering unit 32. The second low pass filtering unit 32 outputs only a pure track error signal by re-filtering the track error signal from which the high frequency component has been removed by the first low pass filtering unit 31.

The track error signal output from the filtering unit 30 (see FIG. 2B) is inverted from the non-inverting input terminal of the first comparator OP ₂ of the track deviation check unit 40 and the second comparator OP ₃ . Is applied to the input.

At this time, the divided voltage Va by the resistance ratio of the third resistor R _{3 to} which a predetermined voltage (+ Vcc) is applied and the first variable resistor VR ₁ to which the output voltage of the third resistor R ₃ is applied. Is applied to the inverting input terminal of the first multiplier OP ₂ .

Further, the second comparator, the second is receiving the output voltage of the fourth resistance (R ₄₎ and said fourth resistance (R ₄₎ to receive applying a predetermined negative voltage (-V _EE) of the non-inverting input terminal (OP ₃₎ The divided voltage Vb based on the resistance ratio of the variable resistor VR ₂ is applied.

The first comparator OP ₂ receiving the divided voltage Va at the inverting input terminal is high when the track error signal (waveform B in FIG. ₂ ) applied to the non-inverting input is higher than the divided voltage Va applied to the inverting input terminal. Output the signal (see waveforms B and C in FIG. 2).

Further, the divided voltage (Vb) than the divided voltage (Vb) applied to the second comparator (OP ₃₎ is a non-inverting input the track error signal (the waveform B 3 degrees) is applied to the inverting input terminal to receive applied to the non-inverting input If small, a high signal is output (see waveforms B and D of FIG. 3).

The logic sum gate 43, which receives the output signal of the first comparator OP ₂ and the output signal of the second comparator OP ₃ , becomes high when any one of the two input signals is HIGH. Output (see also C, D, and E in Figure 3).

The controller 50 receiving the output signal (E in FIG. 3) of the track deviation check unit 40 operating as described above determines that the input signal (E in FIG. 3) is in a low state and is in a high state. If it is determined that the lens has left the track, the control signal is transmitted to the disc drive unit (not shown) so that the recording can be stopped and the recording of the track error part can be retried again.

As described above, the present invention has the effect of not only recording and preserving more accurate data when recording and reproducing a disc player, but also providing a sound closer to the original sound.

Claims (3)

Track error signal generating means for generating a track error signal, pickup means for recording and reproducing data on the track, input means for receiving a track error signal, and removing RF signals mixed with the track error signal applied from the input means. Low-pass filtering means for, the track departure check means for determining whether or not the track departure of the pickup device by receiving the filtered track error signal: and the error signal is determined by receiving the signal output from the track departure check means A track error preventing device of a disc player comprising a control means, wherein the track deviation detecting means comprises: a track upper limit deviation detecting means for determining whether the pickup device deviates from the center of the track by more than an upper limit reference value; Track lower limit deviation detection to determine whether the deviation falls below the lower limit reference value Stage: and trekking error protection device of the disc player, characterized by track deviation wire and constituted by any non-detecting means for combining the output signals of the detection means of the output whether the track deviation of the pick-up device. The non-inverting input terminal of claim 1, wherein the track upper limit deviation detecting unit comprises a first resistor receiving a predetermined positive voltage, a first variable resistor connected to the first resistor, and a signal output from the low pass filtering unit. And a first comparator applied to a voltage terminal and receiving an output voltage between the first resistor and the first variable resistor to a negative voltage terminal. The negative voltage stage of claim 1, wherein the track lower limit deviation detecting unit comprises a second resistor receiving a predetermined negative voltage, a second variable resistor connected to the second resistor, and a signal output from the low pass filtering unit. And a second comparator receiving an output voltage between the second resistor and the second variable resistor to a non-inverting input terminal.