LG-LXD5230-cs-sm 电路图 维修手册.pdf

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1、- 1-1 - CONTENTS SECTION 1. GENERAL SERVICING PRECAUTIONS.1-2 ESD PRECAUTIONS.1-4 SPECIFICATION.1-5 SECTION 2. ELECTRICAL SECTION ADJUSTMENTS.2-1 AUDIO PART ELECTRICAL TROUBLESHOOTING GUIDE. 2-2 BLOCK DIAGRAM.2-11 SCHEMATIC DIAGRAMS.2-13 IC/TR VOLTAGE SHEET . 2-19 WIREING DIAGRAM. 2-21 PRINTED CIRCU

2、IT DIAGRAMS. 2-23 SECTION 3. DVD PART ELECTRICAL TROUBLESHOOTING GUIDE TROUBLESHOOTING .3-1 DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING .3-8 DVD PART SCHEMATIC DIAGRAMS. 3-21 PRINTED CIRCUIT DIAGRAM . 3-29 SECTION 4. EXPLODED VIEWS CABINET AND MAIN FRAME SECTION. 4-1 SECTION 5. SPEAKER PART S

3、PEAKER PART.5-1 SECTION 6. REPLACEMENT PARTS LIST REPLACEMENT PARTS LIST.6-1 RadioFans.CN 收音机爱 好者资料库 SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP 1. Notes for transport and storage 1) The pick-up should always be left in its conductive bag until immediately prior to use. 2) The pick

4、-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 correctly and carefully, taking care to avoid external pressure and impact. I

5、f 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, and for that reason the adjustment point and installation screws should a

6、bsolutely 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) Cleaning the lens surface If there is dust on the lens surface, the dust sho

7、uld 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 attempt to disassemble the pick-up. Spring by excess pressure. If the len

8、s 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 to get inside the pick-up. - 1-2 - Storage in conductive bagDrop impact

9、 NEVER look directly at the laser beam, and dont let contact fingers or other exposed skin. Magnet How to hold the pick-up Pressure Pressure Cotton swab Conductive Sheet SECTION 1. GENERAL RadioFans.CN 收音机爱 好者资料库 NOTES REGARDING COMPACT DISC PLAYER REPAIRS 1. Preparations 1) Compact disc players inc

10、orporate 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 should be handled with care. 2) The pick-up is composed

11、 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 magnetism is present, or where there is excessive dust. 2. Notes for repair 1) Before replacing a component part, first d

12、isconnect 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, do not place the pick-up on the bag. (This is becau

13、se 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-up to come in contact with clothing, in order to prev

14、ent static 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. CLEARING MALFUNCTION You can reset your unit to initial status if malfunction occur(button malfunction, display, etc.). Using a pointed

15、 good conductor(such as driver), simply short the RESET jump wire on the inside of the volume knob for more than 3 seconds. If you reset your unit, you must reenter all its settings(stations, clock, timer) NOTE: 1. To operate the RESET jump wire, pull the volume rotary knob and release it. 2. If you

16、 wish to operate the RESET jump wire, it is necessary to unplug the power cord. - 1-3 - Armband Conductive Sheet Resistor (1 Mohm) Resistor (1 Mohm) VOLUME KNOB UP DOWN VOLUME RESET jump wire RadioFans.CN 收音机爱 好者资料库 ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD) Some semiconductor (solid

17、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 transistors and semiconductor chip components. The following techniques should be u

18、sed 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 touching a known earth ground. Alternatively, obtain and wear a commerc

19、ially 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 assembly on a conductive surface such as aluminum foil, to prevent electro

20、static 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 anti-static can generate electrical charges sufficient to damage ESD devices

21、. 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 install it. (Most replacement ESD devices are packaged with leads electri

22、cally 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 the chassis or circuit assembly into which the device will by installed. C

23、AUTION : 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 brushing together of your clothes fabric or the lifting of your foot from a car

24、peted floor can generate static electricity sufficient to damage an ESD device). CAUTION. GRAPHIC SYMBOLS - 1-4 - THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” THAT MAY BE OF SU

25、FFICIENT 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. - 2-1 - TAPE DECK ADJUSTMENT 1. AZIMUTH ADJUSTMENT Figure 1. Azimuth Adjus

26、tment Connection Diagram CH1 CH2 Speaker Out Playback Mode Head Test Tape MTT-114 L ch R ch GND Dual-trace synchroscope Electronic Voltmeter L out R out Unit ADJUSTMENTS This set has been aligned at the factory and normally will not require further adjustment. As a result, it is not recommended that

27、 any attempt is made to modificate any circuit. If any parts are replaced or if anyone tampers with the adjustment, realignment may be necessary. IMPORTANT 1. Check Power-source voltage. 2. Set the function switch to band being aligned. 3. Turn volume control to minimum unless otherwise noted. 4. Co

28、nnect low side of signal source and output indicator to chassis ground unless otherwise specified. 5. Keep the signal input as low as possible to avoid AGC and AC action. Deck ModeTest TapeTest PointAdjustmentAdjust for PalybackMTT-114Speaker Out DECK Screw Maximum Azimuth Screw SECTION 2. ELECTRICA

29、L SECTION - 2-2 - AUDIO PART ELECTRICAL TROUBLESHOOTING GUIDE VKK PART Does DC - 33V appear at PN301 pin . OK Check the -27V of ZD901(-) Check the Q902 TURN ON Check the -277VLower of C918(-) Replace the Q902 Replace the D908, D909 OK Refer to power Troubleshooting YES YES YES YES YES NO NO NO P-SEN

30、S PART Does +5V appear at ZD900? Check the pattern of IC301 pin . Check the waveform of D907 (+). Check the R901 and Replace ZD 900 Replace the D907 YES YES NO NO 26 31 - 2-3 - POWER CIRCUIT Check the Fuse Check the DC output of C732(+), C731(-) Check the DC Output of IC712, IC751 OK Replace the Fus

31、e Check the 1.5V AC output of D701 Replace the D701 Replace the Transformer YES YES YES YES NO NONO MUTING CIRCUIT (MUTE) Dose “High” appear at Q701, Q702, Q703, Q751, Q752 “B” check the “Low” of Q701, Q702, Q703, Q751, Q752 “C” MUTE Check the IC203 Troubleshooting (ONLY Q201/Q251) Check the “High”

32、of Q704, Q705, Q706 “E” (ONLY Q701/Q751) Replace the Q704, Q705, Q706 Replace the TR Refer to IC 301 Troubleshooting YES YES YES NO NO NO - 2-4 - AUDIO ABNORMAL Check the output of IC701, IC702, IC703 Pin 2, 4 Check the connecting to speaker Check the FUNCTION input terminal Check the input of IC701

33、, IC702, IC703, pin7, 11 Check the 12V output of IC602, IC601 Check the 12V output of IC704 OK YES NO FUNCTION MODE AUDIO ABNORMAL TAPE Check the signal input of IC601 pin6, 23 Refer to “IC201 Troubleshooting” AUX Chekc the signal input of IC600, pin5, 24 Check the signal input of JK400 - 2-9 - Chec

34、k the signal input of IC601 pin3, 26 Check the signal input of PN704 pin11, 13, 15, 17, 19 Check the signal input of IC601 pin4, 25 Refer to “TUNER PACK Troubleshooting” CD TUNER IC301 TROUBLESHOOTING Check the power supplied to IC301 pin17, 46, 72, 90? Refer to “Power Circuit Troubleshooting” Check

35、 the P-SENS Replace the X301 Check the RESET circuit Check the P-SENS “High” of IC301 pin26 Check the oscillation of X301 When power supplying to IC301 pin12. (Low High) Replace the IC301 YES YES YES YES NO NO NO NO - 2-6 - Refer to “IC301 Troubleshooting” IC601 TROUBLESHOOTING IC602 TROUBLESHOOTING

36、 Refer to “Power Circuit Troubleshooting” Check the Data of IC301 pin87, 88 (CD TAPE FUNCTION) Refer to power Troubleshooting Check the Data of IC301 pin 85, 86 Check the patter of IC301 & IC602 Replace the IC601 Check the pattern of IC301 & IC601 Check the power supplied to IC601 pin1 Check the CLK

37、 Data of IC601 pin14, 15 Check the FUNCTION SELECTOR END Check the Power supplied to IC602 pin 1 Check the CLK Data of IC602 pin9, 10 Replace the IC602 YES YES YES YES YES YES NO NO NO NO NO - 2-7 - TUNER PACK TROUBLESHOOTING Check the 9V of PN602 pin2 Check the GND of PN602 pin 4, 10 Check the patt

38、ern Check the DC of C670 Check the power YES NO PLAY Check the VCC supplying to IC201 pin4 Refer to “Power Circuit Troubleshooting” Check the Deck Mecha Replace the Deck Mecha. Replace the IC201 Check the signal output of IC201 pin3, 6 Check the “LOW” of Q201, Q251, “B” YES YES YES NO NO NO - 2-8 -

39、REC (Q252, Q202 ON / R273, R223 HIGH) Check signal supplied to IC203 pin2, 8 ? Check the output of IC203 pin3, 7 Check the “output” of L201 pin5 Refer to “power circuit Troubleshooting” Check the power supplying to C227(+) Check the oscillation of Q204, “E” Check the signal of R212, R262 Check the P

40、attern Check the Vcc power of IC203 Pin6 Check the oscillation of L201 pin 1, 3 Replace the DECK Check the “Low” of Q202, Q252 “B” Replace the Q202, Q252 Check the “Low” of IC501 pin9 Refer to “Power Circuit Troubleshooting” Check the 0.6V of Q205 “B” Replace the L201 YES YES YES YES YES YES YES YES

41、 NO NO NO NO NO NO NO NO - 2-9 - POWER P.C. BOARD (SOLDER SIDE) - 3-1 - 1. Power check flow SECTION 3. DVD PART ELECTRICAL TROUBLESHOOTING GUIDE 2. Test & debug flow - 3-2 - - 3-3 - - 3-4 - - 3-5 - - 3-6 - - 3-7 - DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING 1. SYSTEM 27MHz CLOCK,RESET,FLASH R

42、/W SIGNAL 1) MT1379 main clock is at 27MHz(X501) 2) MT1336 reset is high active - 3-8 - - 3-9 - 3) RS232 waveform during procedure(Downloading) 4) Flash R/W enable signal during download(Downloading) 2. SDRAM CLOCK 1) MT1379 main clock is at 27MHz(X501) 3. TRAY OPEN/CLOSE SIGNAL 1) Tray open/close w

43、aveform - 3-10 - - 3-11 - 2) Tray close waveform 3) Tray open waveform 4. SLED CONTROL RELATED SIGNAL (NO DISC CONDITION) 5. LENS CONTROL RELATED SIGNAL(NO DISC CONDITION) - 3-12 - - 3-13 - 6. LASER POWER CONTROL RELATED SIGNAL (NO DISC CONDITION) 7. DISC TYPE JUDGEMENT WAVEFORM - 3-14 - - 3-15 - 8.

44、 FOCUS ON WAVEFORM 9. SPINDLE CONTROL WAVEFORM (NO DISC CONDITION) - 3-16 - - 3-17 - 10. TRACKING CONTROL RELATED SIGNAL(System checking) 11. RF WAVEFORM 12. MT1379 AUDIO OPTICAL AND COAXIAL OUTPUT (ASPDIF) - 3-18 - - 3-19 - 13. MT1379 VIDEO OUTPUT WAVEFORM 1) Full colorbar signal(CVBS) 2) Y 3) C 14. AUDIO OUTPUT FORM AUDIO DAC 1) Audio