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1、DVD/CD RECEIVER SERVICE MANUAL P/N : 3829RDT044UAUGUST, 2004 MODEL: LGDVT418 SERVICE MANUAL MODEL: LGDVT418 CD-R/RW RadioFans.CN 收音机爱 好者资料库 - 1-1 - CONTENTS SECTION 1.GENERAL SERVICING PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 ESD P
2、RECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5 SECTION 2. AUDIO PART ELECTRICAL TROUBLESHOOTING
3、GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4、 . . . . . . . . . . . . . . . 2-7 WIRNG DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21 PRINTED CIRCUIT DIARGAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23 SECTION 3.DVD PART DV
5、D PART ELECTRICAL TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1 DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING . . . . . . . . . . . . . . . . .3-8 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6、 . . . . . 3-21 DVD PART SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-25 SECTION 4. EXPLODED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 SECTION 5. SPEAKER PART . . . . . . . . . . . . . . . . . . . . . . . .
7、 . . . . . . . . . . . . .5-1 SECTION 6. REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1 RadioFans.CN 收音机爱 好者资料库 - 1-2 - SECTION 1. GENERAL SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP 1. Notes for transport and storage 1) The pick-up should always be
8、 left in its conductive bag until immediately prior to use. 2) The pick-up should never be subjected to external pressure or impact. 2. Repair notes 1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials. 2) The pick-up should always be handled correc
9、tly and carefully, taking care to avoid external pressure and impact. If it is subjected to strong pressure or impact, the result may be an operational malfunction and/or damage to the printed-circuit board. 3) Each and every pick-up is already individually adjusted to a high degree of precision, an
10、d for that reason the adjustment point and installation screws should absolutely never be touched. 4) Laser beams may damage the eyes! Absolutely never permit laser beams to enter the eyes! Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged. 5) Clean
11、ing the lens surface If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used for camera lens).The lens is held by a delicate spring. When cleaning the lens surface, therefore, a cotton swab should be used, taking care not to distort this. 6) Never att
12、empt to disassemble the pick-up. Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do not use any other liquid cleaners, because they will damage the lens.) Take care not to use too much of this alcohol on the swab, and do not allow the alcohol t
13、o get inside the pick-up. Storage in conductive bagDrop impact NEVER look directly at the laser beam, and dont let contact fingers or other exposed skin. Magnet How to hold the pick-up Conductive Sheet Cotton swab Pressure Pressure RadioFans.CN 收音机爱 好者资料库 - 1-3 - NOTES REGARDING COMPACT DISC PLAYER
14、REPAIRS 1. Preparations 1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode).These components are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage, components can be damaged, and for that reason components shoul
15、d be handled with care. 2) The pick-up is composed of many optical components and other high-precision components. Care must be taken, therefore, to avoid repair or storage where the temperature of humidity is high, where strong magnet- ism is present, or where there is excessive dust. 2. Notes for
16、repair 1) Before replacing a component part, first disconnect the power supply lead wire from the unit 2) All equipment, measuring instruments and tools must be grounded. 3) The workbench should be covered with a conductive sheet and grounded. When removing the laser pick-up from its conductive bag,
17、 do not place the pick-up on the bag. (This is because there is the possibility of damage by static electricity.) 4) To prevent AC leakage, the metal part of the soldering iron should be grounded. 5) Workers should be grounded by an armband (1M ) 6) Care should be taken not to permit the laser pick-
18、up to come in contact with clothing, in order to prevent sta- tic electricity changes in the clothing to escape from the armband. 7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin. Resistor (1 Mohm) Conductive Sheet Resistor (1 Mohm) Armband - 1-4 - ESD PRECAUT
19、IONS Electrostatically Sensitive Devices (ESD) Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated circuits and some field-effect transistor
20、s and semiconductor chip components.The following techniques should be used to help reduce the incidence of component damage caused by static electricity. 1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by
21、 touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed for potential shock reasons prior to applying power to the unit under test. 2. After removing an electrical assembly equipped with ESD devices, place the as
22、sembly on a conductive sur- face such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3. Use only a grounded-tip soldering iron to solder or unsolder ESD devices. 4. Use only an anti-static solder removal device. Some solder removal devices not classified as an
23、ti-static can generate electrical charges sufficient to damage ESD devices. 5. Do not use freon-propelled chemicals.These can generate electrical charges sufficient to damage ESD devices. 6. Do not remove a replacement ESD device from its protective package until immediately before you are ready to
24、install it. (Most replacement ESD devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive materials). 7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the protective material to t
25、he chassis or circuit assembly into which the device will by installed. CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER SAFETY PRECAUTIONS. 8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion such as the brushi
26、ng together of your clothes fabric or the lifting of your foot from a carpeted floor can gen- erate static electricity sufficient to damage an ESD device). CAUTION. GRAPHIC SYMBOLS THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE SERVICE PERSONNEL T
27、O THE PRESENCE OF UNINSULATED “DAN- GEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK. THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE. - 1-5
28、 - SPECIFICATIONS - 1-6 - MEMO - 2-1 - ELECTRICAL TROUBLESHOOTING GUIDE INSERT POWER CORD. TURN ON THE RED LED? IS POWER ON? CHECK POWER PLUG AND POWER SUPPLY CIRCUIT . DOES INITIAL READ WORK? DOES IT PLAY? YES NO YES YES OK NO YES NO NO CHECK POWER SUPPLY CIRCUIT . CHECK LASER CIRCUIT . CHECK TRACK
29、ING SERVO CIRCUIT. TURN POWER ON. CHECK FOCUS CIRCUIT. CHECK DISC. DOES IT OUTPUT AUDIO? YES NO CHECK AUDIO CIRCUIT. 1. Power check flow SECTION 2. AUDIO PART - 2-2 - 2.AUDIO .COM CIRCUIT POWER ON Does it appear DVD Error at FLD? Does AV 1/2, TV, AUDIO, OPTICAL IN, COAXIAL IN, FM87.5 appear at FLD?
30、Check Connector(PN902)if is normally. Check power part of Main B/D. Check oscillator of x101. Check if IC101 PIN1 is High. Check if IC101 PIN11 is High. Check if IC101 PIN 17, 46, 72, 90 is high (5V). Check if IC101 PIN26 is High. Replace IC101. Does CD/DVD appear at FLD? Reconnet it. Refer to SMPS
31、OK. Refer to oscillator Circuit. Check DVD Reset Waveform. Check IC101 Reset Wavefrom. Check 5V line. Check Power dection Circuit. Does LOADING appear at FLD? Does no Disc or Time appear at FLD? Check if DVD an Audio Micom Interface is OK. Check power. Check DVD Module. Check SMPS. - 2-3 - 3.FRONT C
32、IRCUIT (1/2) - 2-4 - 4.FRONT CIRCUIT (2/2) BLOCK DIAGRAM 2-52-6 2-72-8 SCHEMATIC DIAGRAMS FRONT SCHEMATIC DIAGRAM 2-92-10 MICOM SCHEMATIC DIAGRAM 2-112-12 I/O SCHEMATIC DIAGRAM 2-132-14 DSP SCHEMATIC DIAGRAM 2-152-16 AMP SCHEMATIC DIAGRAM 2-172-18 SMPS-WIDE SCHEMATIC DIAGRAM 2-192-20 POWER SCHEMATIC
33、 DIAGRAM 2-212-22 WIRING DIAGRAMS 2-232-24 PRINTED CIRCUIT DIAGRAMS MAIN P.C. BOARD (COMPONENT SIDE) 2-252-26 MAIN P.C. BOARD (SOLDER SIDE) 2-272-28 FRONT P.C.BOARD (SOLDER SIDE) FRONT P.C.BOARD (COMPONENT SIDE) 2-292-30 POWER P.C.BOARD 2-312-32 MEMOMEMO - 3-1 - 1. Power check flow ELECTRICAL TROUBL
34、ESHOOTING GUIDE SECTION 3. DVD PART - 3-2 - 2. System operation flow Power On 1. 8032 initializes SERVO, DSP & RISC registers 2. Write RISC code to SDRAM 3. Reset RISC Show LOGO Tray Closed? Tray Close to Closed position NO SLED at Inner Side ? SLED Moves to Inner Positi on NO YES YES Reci eve OPEN/
35、CLOSE Key? 1. Execute Pressed Key & IR Key 2. System operation Routine Loop NO 1. Stop Playback & Open Tray 2. Display tray open message & LOGO Receive CLOSE Key? NO YES YES 1. Judge whether have disc and disc type 2. Jump to related disc reading procedure - 3-3 - 3.Test & debug flow TEST Check the
36、AC Voltage Power PCBA(110V or 220V) NO Replace power PCBA or AC transformer. YES Switch on the Power PCBA Is the DC Voltage outputs OK? (5V,1.8V,3.3V,8V,12V) Repair or Replace Power PCBA NO Make sure the main PCBA dont short on VCCs and switch it on. YES Is 3.3V and 1.8V DC outputs normal on main PC
37、BA? Check the regulators or related diodes. NO YES Connect to PC RS232 Cable and update the FLASH memory code. Update FLASH successfully? A YES NO 1. Check 27MHz system clock. 2. Check system reset circuit. 3. Check FLASH R/W enable signal PRD,RWR. 4. Check RS232 SIGNALS. 5. Check FLASH Memory relat
38、ed circuit. - 3-4 - A RESET or Power On. NONO YES NO YES NO YES YES B NO NO NO YES YES NO NO YESYES YES Show LOGO? Flash Memory operates properly? Check connection lines between FLASH & MT1389 and the FLASH access time whether is suitable or not. SDRAM works properly? Check connection lines between
39、SDRAM & MT1389 and the SDRAM is damaged. MT1389 VIDEO outputs properly? Check the related circuit of MT1389. Have TV signal output? Check the filtering and amp circuit of TV signal. Check AV cable connection to TV set. Does Tray move inside when it is not at closed position? Normal TROUT & TRIN sign
40、als? Check the load OPEN & CLOSE switch Normal TRCLOSE & TROPEN signal? Normal LOAD+ & LOADsignal? Check the cable connection between main PCBA and loader. Check the Tray control IO pins on MT1389 & IP4504. Check the Tray control amplifying circuit on Motor driver. - 3-5 - B NONO NO NO NONO NO YESYE
41、S YES YES YESYES YES Does the SLED move to inner side when it is at outter position? Motor Driver STBY Pin is High? Check the connection line of STBY signal. Is FMSO DC Level higher than 1.4V? Check the related circuit of FMSO. SL+ and SL- output properly? Check the amp circuit on motor driver. Chec
42、k the cable connection with MECHA. Do not put in disc and tray close. C Optical Lens has movements for searching Focus? Proper FOSO outputs to motor driver? Check FOSO connection on MT1389 and motor dirver. Proper F+ & F- outputs? Check the amp circuit on motor dirver. Check cable connect on with pi
43、ck-up head. - 3-6 - D C YES NO YES YES NO NO Does spindle rotate?Proper DMSO signal on MT1389 Check DMSO related circuit on MT1389. SP+ & SP- output properly? Check the spindle control amp circuit of motor driver. Check the cable connection between spindle and main PCBA. YES YES NO NO Laser turns on
44、 when reading disc? NO NO YES NO YES YES NO LD01 or LD02 output properly? Check the laser power circuit on MT1336 and connecting to power transistor. Collector voltage of power transistor is OK? Check the related circuit on laser power transistor Check cable connection between transistor ouput and p
45、ick-up head. Put disc in?Laser off Disc ID is correct? Proper RFL signal on MT1389? Check the related circuit on MT1389 RFL signal. Check LDO1 & LDO2 signal YES - 3-7 - YES NO YES YES D NONO NO YES NO E YES Normal TEO Signal on MT1389? Check the related circuit on MT1389 Track On OK? Properly TRSO s
46、ignal on MT1389? T+ & T- output properly? Check the TRSO connection on MT1389 and motor dirver. Check the tracking control amp circuit on motor driver. Check cable connection on pick-up head. Disc is play ?Check RFO & RFLVL signal waveform. NONO YES YES YES Focus ON OK? Proper signals on A,B,C,D of
47、MT1389 Check connections between MT1389 and pick-up head. Check FEO signal on MT1389 Check FOSO signal on MT1389 Check the FOSO connection on MT1389 and motor driver. YES NO - 3-8 - Normal IR.VFD & Front pannel key functions? Communications between IR.VFD Front pannel key & MT1389 is n orma lly? Che
48、ck communication lines on MT1389. NO YES Check the cable connection on Front pannel. TEST END YES Normal Audio output when disc playback? Audio PWM IC received correct data stream? Check connection between MT1379 & Audio PWM IC. Normal Audio PWM IC out? Check the related circuit of Audio PWM IC. Che
49、ck Audio filter,amplify,mute circuit. NONO NO YES YES YES E NO - 3-9 - FIG 1-1 FIG 1-2 DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING 1. SYSTEM 27MHz CLOCK,RESET,FLASH R/W SIGNAL 1) MT1379 main clock is at 27MHz(X501) 2) MT1336 reset is high active - 3-10 - FIG 1-3 FIG 1-4 3) RS232 waveform during procedure(Downloading) 4) Flash R/W enable signal during download(Downloading) - 3-11 - FIG 2-1 FIG 3-1 2. SDRAM CLOCK 1) MT1379 main clock is at 27MHz(X501) 3.TRAY OPEN/CLOSE SIGNAL - 3-12 - FIG 4-1 FIG 5-1 4. SLED
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