CN2371641Y - Audio-visul CD player with error correcting circuit - Google Patents

Abstract

The utility model relates to an audio-video CD player with an error correcting circuit. Mainly a scuffing voltage signal holding circuit, a low frequency response compensation circuit and a track error signal neutral balance circuit are inserted between a radio frequency amplification integrated circuit and a digital servo control integrated circuit. Moreover, a frequency compensation circuit is additionally arranged between the digital servo control integrated circuit and a coil/motor driver simultaneously. Thus, the utility model solves the problems that the low-frequency response of the digital servo control integrated circuit is poor, the over scuffing ability is poor, and the phenomena of skipping stitch and jumping track occur. Fitted with the circular error signal neutral balance circuit, the utility model can provide proper compensation for neutral voltage excursion. The utility model has an excellent track cycling ability.

Description

Video and audio CD disc player with Error-Correcting Circuit

The utility model relates to video and audio CD disc player for household use (VIDEO-CD PLAYER) (VCDPLAYER) or super video and audio CD disc player (SUPER-VCD PLAYER) (SVCD PLAYER), relate more specifically to improving the servocontrol ability of player, has good fault-tolerant usefulness, but make second-rate and CD-RW discsCD-RW that the certain degree scratch arranged a kind of video and audio CD disc player of normal play still with Error-Correcting Circuit

Video CDs (VIDEO CD) is (VCD) because volume is same as the size of general CD audio sheet (CD), yet it is really stereo to reach the dynamic image and the high pass of playing 74 minutes, be the emerging product of the traditional video-tape of a replacement, because manufacturer reaches under the factor that reduces cost, still flow on the market for some bad CD-RW discsCD-RW during manufacture, and cause the quality drop of video CDs very big, and have under the difference of consumption grade aspect, promptly may buy the not good CD-RW discsCD-RW of scratch or quality, and cause can't normal play or produce bouncing pilotage, the abnormal occurrence of jumping onto the tracks, in addition, be not good at also having the situation of quickening the video disc damage and can't using for the preserving type of CD-RW discsCD-RW, therefore, for the second-rate consumption market of this kind video disc, how to make player still can play normally, be the problem that manufacturer makes great efforts and institute's desire is improved.

On the structure of known general video and audio CD disc player (VCD PLAYER) or super video and audio CD disc player (SVCDPLAYER), generally for as shown in Figure 7, for by optical facilities 90, coil/motor driver 70, radio frequency/focus error signal amplification circuit 50, digital servo control integrated circuit 60, microprocessor 80, mpeg decoder 91 is formed jointly, these optical facilities 90 are for supplying to read CD, the video disc signal of VCD and SVCD specification, and send required signal, and coil/motor driver 70, focus on for driving, the Spindle Motor and the long distance tracking motor that follow the path circle and promote player, so that optical head structure 90 normally follows rail or the action of jumping onto the tracks, microprocessor 80 is control radio frequency/focus error signal amplification circuit 50 and digital servo control integrated circuit 60, the work of control complete machine.It is the integrated package of OM-1168 that radio frequency/focus error signal amplification circuit 50 (its each pin is defined as Fig. 8) adopts model, it is a CMOS type IC, be applicable in the CD-ROM system of 12 times of speed/16 times speed, there are radio frequency amplifier, focus error signal amplifier, rf agc amplifier and APC circuit etc. in inside, data-signal and the error signal that optical facilities 90 can be sent are carried out the amplification of suitable degree, handle for subsequent conditioning circuit.And digital servo control integrated circuit 60 (its each pin is defined as Fig. 9) employing model is the integrated circuit of OM-1368, there are servo functions such as A/D, D/A converter, radiofrequency signal processing, radiofrequency signal are decoded, focusing follows rail, jump onto the tracks its inside, and automatic gain is adjusted functions such as Spindle Motor control and error in data correction.And mpeg decoder 91 is image and voice signal (A/V) with the VCD disk data transforms decode of sending here (decompression), and image that this sends and voice signal can directly be fed through televisor, reach the effect of watching VCD, SVCD film or program.

On the framework of aforementioned conventional DVD player, the good CD-RW discsCD-RW of play quality is no problem still, yet, for VCD CD-RW discsCD-RW second-rate, that orbit error has scratch greatly and easily, the phenomenon that bouncing pilotage takes place quite easily, jump onto the tracks even can't play.Though include the error correction function in the aforesaid digital servo control integrated circuit 60, yet only terminate in high frequency, and for the relatively poor CD-RW discsCD-RW of run-of-the-mill, its mistake all occurs in the part of low frequency, as laser spot during by scratch zone (can't read signal), the moment high-frequency impulse that is produced, cause promptly following that the rail DC voltage is improper beats, the abnormal occurrence that causes bouncing pilotage or jump onto the tracks, if in the time of strengthening its LF-response, can reduce and eliminate above-mentioned phenomenon, and for the excessive video disc of orbit error, owing to there be not the auxiliary of other circuit, also for can't successfully playing, so the needs that the design of traditional video and audio CD disc player can't be realistic truly have necessity of being improved.

Based on above reason, the utility model mainly promptly is to provide a kind of video and audio CD disc player with height fault-tolerant ability, insert Error-Correcting Circuit (error correctioncircuit) in the inner appropriate location of traditional player, to reach the usefulness that improves the video and audio CD disc player.

Fundamental purpose of the present utility model provides a kind of video and audio CD disc player with Error-Correcting Circuit at the shortcoming that above-mentioned traditional laser disc player exists.

To achieve these goals, the utility model adopts following technical scheme:

This has the video and audio CD disc player of Error-Correcting Circuit, by optical facilities, coil/motor driver, microprocessor, radio frequency/focus error signal amplification circuit, the digital servo control integrated circuit, mpeg decoder is formed, the input end of optical facilities and output terminal are for being connected with coil/motor driver and radio frequency/focus error signal amplification circuit respectively, radio frequency/the output terminal of focus error signal amplification circuit and the input end of coil/motor driver are connected to the digital servo control integrated circuit jointly, the data output end of digital servo control integrated circuit is connected to mpeg decoder, demoder output video-audio signal is characterized in that:

Be provided with a LF-response compensating circuit and a scratch voltage signal holding circuit between said radio frequency/focus error signal amplification circuit and the digital servo control integrated circuit, said LF-response compensating circuit is formed with a signal amplifier and two-way switch, the input end of signal amplifier is connected with the signal error end (SBAD) of radio frequency/focus error signal amplification circuit, the two ends of two-way switch are connected with the control end points of radio frequency/focus error signal amplification circuit and the rail signal end of following of coil/motor driver respectively, scratch voltage signal holding circuit, be serially connected in the electric capacity that follows the two-way switch on the rail signal circuit and be connected across on this loop with another and constituted, the control end of two-way switch is connected with described signal error end (SBAD).

Have the video and audio CD disc player of Error-Correcting Circuit, it is characterized in that: also comprise a rail error signal neutral balance circuit, this circuit is serially connected with and follows on the rail signal circuit for to form a traffic pilot by two groups of two-way switchs.

Video and audio CD disc player with Error-Correcting Circuit, it is characterized in that: comprise that also one is arranged at the frequency compensated circuit between coil/motor driver and the digital servo control integrated circuit, this frequency compensated circuit forms a low-pass filter, and is synchronous with said LF-response compensating circuit.

Have the video and audio CD disc player of Error-Correcting Circuit, it is characterized in that: said LF-response compensating circuit also comprises a delay circuit.

Have the video and audio CD disc player of Error-Correcting Circuit, it is characterized in that: said delay circuit can be made of several phase inverters and RC integrating network.

The utility model is owing to be provided with scratch voltage signal holding circuit between radio frequency amplification circuit and digital servo control integrated circuit, LF-response compensating circuit and rail error signal neutral balance circuit, scratch voltage signal holding circuit can be when having recorded scratch, the temporarily disconnected original signal, and remain on previous voltage status, reach and keep optical read head and still remain in the original track, and the bad phenomenon that unlikely generation is jumped onto the tracks, carry out low-frequency compensation by the LF-response compensating circuit to following the rail signal, and suitably suppress the high frequency composition, reach the high-frequency signal that reduction is produced by the microgroove scratch, to solve the problem of bouncing pilotage, in addition, rail error signal neutral balance circuit is when the video disc track has suitable error, mid-point voltage from the normal moveout correction drive signal, so that optical read head is stabilized on the correct track, therefore, this real video and audio CD disc player has following advantage:

1. be provided with the LF-response compensating circuit: be matched with the frequency range of VCD broadcasting speed, and can improve the response of the low frequency signal in VCD video disc scratch zone, reach the bouncing pilotage phenomenon of reduction because of the high-frequency signal of microgroove scratch.

2. in following the rail signal, when taking place when unusual, skip digital servo controller and low frequency signal is directly sent in the driving circuit in the mode of bypass, reach more step compensate for low frequency response gain.

3. be provided with the defective voltage hold circuit, must keep its voltage in previous state when making, remain on the same track, be unlikely to produce and jump onto the tracks with the optical lens of keeping optical facilities by the scratch zone.

4. rail error signal neutral balance circuit is set, the video disc of different rail errors is driven the correction of mid-point voltage automatically, the lens correction that makes optical facilities is unlikely the problem that generation can't be read to correct track.

Below in conjunction with drawings and Examples, the utility model is described in detail further:

Fig. 1 is a circuit box principle schematic of the present utility model.

Fig. 2 is a circuit theory synoptic diagram of the present utility model.

Fig. 3～Fig. 6 is each element circuit synoptic diagram of the present utility model.

Fig. 7 is the circuit box principle schematic of traditional video and audio CD disc player.

Fig. 8 is the pin synoptic diagram of known radio frequency amplifier integrated block.

Fig. 9 is the pin synoptic diagram of known digital servocontrol integrated package.

As shown in Figure 1, the ultimate principle of the ultimate principle, circuit structure that the utlity model has the video and audio CD disc player of Error-Correcting Circuit and traditional video and audio CD disc player (VCD PLAYER) or super video and audio CD disc player (SVCDPLAYER), circuit structure are mutually roughly the same, still use the radio frequency/focus error signal amplification circuit 50 and the digital servo control integrated circuit 60 of identical numbering, and difference is described below:

Between radio frequency/focus error signal amplification circuit 50 and digital servo control integrated circuit 60, have additional a scratch voltage signal holding circuit 10, an one LF-response compensating circuit 20 and a rail error signal neutral balance circuit 30, and between digital servo control integrated circuit 60 and coil/motor driver 70, also have additional a frequency compensated circuit 40, this frequency compensated circuit 40 is a low-pass filter structure, and for to be synchro control with aforesaid LF-response compensating circuit 20, this frequency compensated circuit 40 is in order to reduce the higher servo frequency working range of this digital servo control integrated circuit 60, reach raising and remedy its LF-response by the scratch zone, reach and allow late-class circuit more not be subject to the scratch influence, and scratch voltage signal holding circuit 10, make when laser spot is regional by scratch, automatically voltage signal is maintained original voltage reference, remain in the original track with the optical lens of keeping in the optical facilities 90, solution is by the phenomenon of jumping onto the tracks in scratch zone, rail error signal neutral balance circuit 30, main error condition according to track, can adjust automatically, provide in order to drive the moving mid-point voltage of horse, optical lens is positioned on certain track, the reason orbit displacement does not cause the problem that can't read, therefore, after the utility model improves on traditional circuit, reached and make the video and audio CD disc player have error recovery and fault tolerance.

About each element circuit of the present utility model detailed circuit partly, can be in regular turn referring to Fig. 2～6, Fig. 2 is the circuit theory synoptic diagram of whole player, several joints in drawing left side are for supplying to be connected to optical facilities 90, several joints of the drawing rightmost side are for supplying to be connected to mpeg decoder 91 places, place, drawing the top is the complete machine power supply, drawing central authorities promptly mainly constitute with four integrated circuit, be respectively microprocessor 80, digital servo control integrated circuit 60, coil/motor driver 70 and radio frequency/focus error signal amplification circuit 50, wherein, coil/motor driven 70 integrated circuit are associated with frequency compensated circuit 40, then be associated with scratch voltage signal holding circuit 10 in radio frequency/focus error signal amplification circuit 50, LF-response compensating circuit 20 and rail error signal neutral balance circuit 30, the output signal of coil/motor driver 70 is for directly being fed through optical facilities 90 places, the input end of radio frequency/focusing error amplification circuit 50 receives the data-signal that optical facilities 90 are sent into, the signal of 60 received RFs of digital servo control integrated circuit/focus error signal amplification circuit 50, and control relatively outside this coil/motor driver 70, also simultaneously the data-signal that takes out is fed through follow-up mpeg decoder 91 places, reaches decipher and decode original signal.

Should be noted that, this radio frequency/error signal amplification circuit 50 follows rail signal pin (TRDAC) for a defects detection pin (DEFECT) and is arranged, this defects detection pin (DEFECT) is for being connected directly in coil/motor driver 70, this signal triggers the frequency compensated circuit 40 (as Fig. 1) in this coil/motor driver 70, carry out low-frequency compensation according to this, should be and be connected in parallel for the rail signal pin (TRDAC) that follows for the rail signal pin of sending by radio frequency/focus error signal amplification circuit 50 (TRDAC) that follows with the digital servo control integrated circuit 60 of figure right side of face, and be fed through simultaneously in coil/motor driver 70, this design mainly is when predicting the video disc defectiveness, directly by radio frequency/focus error signal amplification circuit 50 send carry out low-frequency compensation follow rail signal (TRDAC) to coil/motor driver 70 places, and wouldn't use digital servo control integrated circuit 60 follow the rail signal, when treating that the video disc flaw indication disappears, then radio frequency/focus error signal amplification circuit 50 follows rail signal pin (TRDAC) for being the off position of suspension joint, promptly revert to the control that is subjected to digital servo control integrated circuit 60 this moment, this measure, its purpose promptly is to remedy the not good problem of LF-response of digital servo control integrated circuit 60 itself, the practice by aforementioned bypass (BYPASS), reach to improve and follow the LF-response of rail signal, make to the utlity model has the fault-tolerant usefulness of good video disc.

For aforementioned each element circuit detailed structure partly, can continue referring to Fig. 3～shown in Figure 6, Fig. 3 be the circuit diagram of microprocessor 80, and it mainly adopts a model is 8032 microcontroller, and its each output input pin is then for for other integrated circuit usefulness of control; Fig. 4 is the circuit diagram of digital servo control integrated circuit 60, the main model with 100 pins that adopts is OM 1368 a digital servos control integrated package, all the other then are necessary peripheral circuit element, promptly for being connected to M PEG demoder 91 and microprocessor 80, the output input pin of drawing lower left is for supplying to be connected to radio frequency/focus error signal amplification circuit 50 for output input pin below drawing upper right side and the figure; Fig. 5 is the circuit diagram of radio frequency/focus error signal amplification circuit 50, the drawing middle position mainly adopts a tool 32 pins, model is radio frequency/focus error signal amplifier integrated block of OM 1168, drawing below is with two two-way switchs 31,32 constitute rail error signal neutral balance circuit 30 of the present utility model, the drawing upper right side is one by two-way switch 11 and resistance 12, the scratch voltage signal holding circuit 10 (seeing empty frame) that electric capacity 13 is formed, the input end TEA of this scratch voltage signal holding circuit 10 is connected with the TEN end points of radio frequency/focus error signal amplification circuit 50, and its output terminal TEB is connected to the input end of the rail error signal neutral balance circuit 30 of below of drawing, and more thus the output terminal of balancing circuitry 30 form the TE end points be connected to digital servo control integrated circuit 60, and the drawing top position more comprises one by several transistors 21～23, several phase inverters 24～27 and the two-way switch 28 common LF-response compensating circuits of forming 20 (seeing empty frame), wherein, the input end of LF-response compensating circuit 20 is connected with the signal error end (SBAD) of radio frequency/focus error signal amplification circuit 50, and transistor 21～23 and phase inverter 24 are for forming an inverting amplifier, other phase inverters 25～27 and relevant RC integrating circuit are composition one delay circuit, the output terminal of delay circuit then forms defects detection pin (DEFECT), this pin also is connected to the control end of two-way switch 28, the I/O end of this two-way switch 28 is respectively with TEA and follow rail signal pin TRDAC and be connected, so, at this defects detection pin (DEFECT) is under the high potential state, can directly make the TEA signal directly with follow rail signal pin (TRDAC) and be communicated with, and skip aforementioned digital servo control integrated circuit 60, make control signal no longer be subjected to the not good restriction of integrated circuit 60 LF-response own, defects detection pin (DEFECT) and follow rail signal pin (TRDAC) for the upper right side of coil/motor driver 70 of being fed through Fig. 6 simultaneously by transistor 41, resistance 43,44,45 and electric capacity 42,46,47 frequency compensated circuits of being formed 40 (seeing the empty frame of Fig. 6), again thus the output terminal of frequency compensated circuit 40 as the drive signal of coil/motor driver 70, this frequency compensated circuit 40 is actually a low-pass filter, when defects detection pin (DEFECT) is noble potential (when being the generation of video disc defective), promptly allow transistor 41 conductings and make entire circuit form a low-pass filtering, to reach the effect that improves LF-response.

When video disc is normal condition, the signal error end SBAD of the radio frequency of Fig. 5/focus error signal amplification circuit 50 is electronegative potential, so the two-way switch 11 of drawing top is connection, another two-way switch 28 is for disconnecting, so the TEN signal that integrated circuit 50 is sent can pass straight through to the TEB end points through TEA, rail error signal neutral balance circuit 30 through the drawing below is fed through in the digital servo control integrated circuit 60 of Fig. 4 by the TE end points again, digital servo control integrated circuit 60 is handled to form and is followed rail signal pin (TRDAC) for drive coil/motor drivers 70 thus, this moment aforesaid scratch voltage signal holding circuit 10, the frequency compensated circuit 40 of LF-response compensating circuit 20 and Fig. 6 all is duty, for Fig. 5 two two-way switchs 31 of the rail error signal neutral balance circuit 30 of below, 32 for forming a traffic pilot, it is for when video disc is inserted, promptly by 32 conductings of microprocessor control one two-way switch, to carry out the correcting track mid-point voltage, after proofreading and correct mid-point voltage, promptly close and make again another two-way switch 31 connections and recovery normal, make when inserting video disc at every turn, all carry out the correction of mid-point voltage automatically, make it reach the data that read correct path, the problem that can't read and unlikely generation rail error is excessive.

When radio frequency/rail error signal amplification circuit 50 of Fig. 5 detects the video disc scratch or has other unusual, promptly allow its signal error end SBAD be noble potential, the feasible amplifier work of forming by several transistors 21～23, make phase inverter 24 send electronegative potential and disconnect with two-way switch 11, this measure, promptly cut off the TEA signal and no longer send into, so the electric capacity 13 by Fig. 5 upper right corner provides a current potential maintenance effect, and make the TEB signal remain on last potential state and unlikely change, this characteristic can make the optical lens of optical facilities still maintain on the original track, and be not subjected to the video disc scratch and produce the problem of jumping onto the tracks, also because it dynamically cuts off input source, also eliminate action because of the improper auto zero of video disc defective, the fault-tolerant ability of the scratch of raising so, is promptly arranged.

In the time of aforementioned startup scratch voltage signal holding circuit 10, after the time delay of the delay circuit of being formed by three phase inverters 25～27 and the RC integrating circuit of Fig. 5 (in order to avoid misoperation), also make defects detection pin (DEFECT) present noble potential and connection two-way switch 28 simultaneously, follow rail signal pin (TRDAC) and locate and the TEA signal directly passed to, for starting LF-response compensating circuit 20 and carrying out low-pass filtering treatment, make coil/motor driver 70 be subjected to the signal of low-frequency compensation and work by the top-right frequency compensated circuit 40 of Fig. 6.

Claims (5)

1, a kind of video and audio CD disc player with Error-Correcting Circuit, this laser disc player is by optical facilities, coil/motor driver, microprocessor, radio frequency/focus error signal amplification circuit, the digital servo control integrated circuit, mpeg decoder is formed, the input end of optical facilities and output terminal are for being connected with coil/motor driver and radio frequency/focus error signal amplification circuit respectively, radio frequency/the output terminal of focus error signal amplification circuit and the input end of coil/motor driver are connected to the digital servo control integrated circuit jointly, the data output end of digital servo control integrated circuit is connected to mpeg decoder, demoder output video-audio signal is characterized in that:

Be provided with a LF-response compensating circuit and a scratch voltage signal holding circuit between said radio frequency/focus error signal amplification circuit and the digital servo control integrated circuit, this LF-response compensating circuit is formed with a signal amplifier and two-way switch, the input end of signal amplifier is connected with the signal error end (SBAD) of radio frequency/focus error signal amplification circuit, the two ends of two-way switch are connected with the control end points of radio frequency/focus error signal amplification circuit and the rail signal end of following of coil/motor driver respectively, and scratch voltage signal holding circuit, then be serially connected in the electric capacity that follows the two-way switch on the rail signal circuit and be connected across on this loop with another and constituted, the control end of two-way switch also is to be connected with described signal error end (SBAD).

2, the video and audio CD disc player with Error-Correcting Circuit as claimed in claim 1 is characterized in that: also comprise a rail error signal neutral balance circuit, this circuit is serially connected with and follows on the rail signal circuit for to form a traffic pilot by two groups of two-way switchs.

3, the video and audio CD disc player with Error-Correcting Circuit as claimed in claim 1, it is characterized in that: comprise that also one is arranged at the frequency compensated circuit between coil/motor driver and the digital servo control integrated circuit, this frequency compensated circuit forms a low-pass filter, and is synchronous with aforementioned LF-response compensating circuit.

4, the video and audio CD disc player with Error-Correcting Circuit as claimed in claim 1, it is characterized in that: described LF-response compensating circuit also comprises a delay circuit.

5, the video and audio CD disc player with Error-Correcting Circuit as claimed in claim 4 is characterized in that: this delay circuit can be made of several phase inverters and RC integrating network.

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