LG-LMU1050-cs-sm 电路图 维修手册.pdf

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1、3CD CHANGER DVD KARAOKE SYSTEM SERVICE MANUAL MODEL: LM-U1050A,LMS-U1050 SERVICE MANUAL MODEL: LM-U1050A,LMS-U1050 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. ELECTRICAL SECTION TROUBLESHOOTING GUI

3、DE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 AUDIO PART TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4、. . . . . . . . . . . . . . . . . . . 2-27 SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-28 WIREING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-43 PRINTED

5、CIRCUIT DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-45 SECTION 3. EXPLODED VIEWS CABINET AND MAIN FRAME SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1 TAPE DECK MECHANISM (A/R & A/S : RIGHT A/R DECK) . .

6、 . . . . . . . . . . . . . . . . . . . . . . .3-3 TAPE DECK MECHANISM (A/R & A/S : LEFT A/S DECK) . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5 CD MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7 SECTION 4. SPEA

7、KER PART SPEAKER PART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 SECTION 5. REPLACEMENT PARTS LIST REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1 Rad

8、ioFans.CN 收音机爱 好者资料库 - 1-2 - 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-up should never be subjected to external pressure or impact. 2. Repair

9、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. If it is subjected to strong pressure or impact, the result may be an ope

10、rational 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 absolutely never be touched. 4) Laser beams may damage the eyes! Absolute

11、ly 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 should be cleaned away by using an air bush (such as used for camera lens).

12、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 lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do not

13、 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. Storage in conductive bagDrop impact NEVER look directly at the laser beam, and dont let contact fingers or other exp

14、osed skin. Magnet How to hold the pick-up Conductive Sheet Cotton swab Pressure Pressure SECTION 1. GENERAL RadioFans.CN 收音机爱 好者资料库 - 1-3 - NOTES REGARDING COMPACT DISC PLAYER REPAIRS 1. Preparations 1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode).These comp

15、onents 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 of many optical components and other high-precision components. Care must

16、 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 repair 1) Before replacing a component part, first disconnect the power supply lead wire from the unit 2) All equipment, mea

17、suring 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 because there is the possibility of damage by static electricity.) 4) To prev

18、ent 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 prevent sta- tic electricity changes in the clothing to escape from the arm

19、band. 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 good conductor(such as driver), simply short the RESET jump wire on

20、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 wish to operate the RESET jump wire, it is necessary to unplug the po

21、wer cord. Resistor (1 Mohm) Conductive Sheet Resistor (1 Mohm) Armband RESET jump wire VOLUME VOLUME KNOB DOWN UP - 1-4 - ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD) Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are calle

22、d 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 used to help reduce the incidence of component damage caused by static electricity. 1. Immediate

23、ly 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 commercially available discharging wrist strap device, which should be removed for potential shock rea

24、sons 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 sur- face such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3. Use only a grounded-tip soldering iron

25、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. 5. Do not use freon-propelled chemicals.These can generate electrical charges sufficient to

26、 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 electrically shorted together by conductive foam, aluminum foil or comparable conductive materials).

27、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. CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER SAFETY P

28、RECAUTIONS. 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 carpeted floor can gen- erate static electricity sufficient to damage an ESD device). CAUTION. GR

29、APHIC SYMBOLS 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 SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK. THE EXCLAMATION POINT WITHIN AN EQUILATER

30、AL TRIANGLE IS INTENDED TO ALERT THE SERVICE PER- SONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE. - 1-5 - SPECIFICATIONS NOTE : Specification are subject to change without notice in the course of product improvement. - 1-6 - - 2-1 - VKK CHECK P-SENS PART CHECK CN701 3PI

31、N DC -33V check IC301 51PIN voltage check SMPS Assy CN904 5PIN 5V operation check MAIN PCB CN701 5PIN 5V MAIN PCB CN301 4PN 5V check Refer to SMPS Troubleshooting Refer to SMPS Troubleshooting CN701 contact condition check MAIN PCB PATTERN disconnection check TROUBLESHOOTING GUIDE YES YES NO NO FRON

32、T PN301 4PIN 5V check FRONT IC304 operation status checck u-COM 26PIN 5V check YES YES YES YES YES YES NO NO Input voltage 4V or higer, output voltage 2.1V or higer operation check IC304 KIA7042 replacement SECTION 2. ELECTRICAL - 2-2 - Muting circuit Troublrshooting (MUTE condition) Q752(A102) Base

33、 “HIGH” Q604, Q605(D1302) BASE “HIGH” check c-COM operation status check Replace each related TR Q603(A102) operation status check Replace when Q603(A102) is defective c-COM 2PIN(A-MUTE) LINE check CN942/CN701 connection status check MUTE YES YES YES YES NO NO NO Unfelt voice Input check (AUX 9.36 T

34、UNER 6/39 TAPE 7/38CD 8/37PIN) Check input and operation status for each function YES NO IC601 20/25PIN output check Refer to IC401(NJW1190) IC specification YES NO IC601 input check (22/23PIN) c-COM check and (CLK/DATA check) YES NO IC601 output check (24PIN) NORMAL Check IC401 24PIN cover 8V and p

35、ower circuit YES NO Power operation staus check R634 180(9.1)V check YES YES NO - 2-3 - Specific FUNCTION MODE unfelt voice TAPE IC202 9PIN (PB MUTE) operation check c-COM 301 3.4PIN CLK/DATA operation check DECK HEAD WIRE connection status check Refer to IC201 Troubleshooting IC201 input check (HAE

36、D input) “A”DECK 32,39 “B”DECK 34,37 YES YES NO IC202 14PIN HIGH operation check Q212(A102) BASE LOW check Q201.202(GATE) HIGH operation check NO IC201 output check (5, 26PIN) IC401 7, 38 signal input check YES NO Replace IC202 YES NO Q212(A101) EMITTER 5V check Q213(C103 COLLECTOP LOW) operation ch

37、eck Replace Q213(C103) YES NO YES Q201,202 (DRAIN) GND check YES Replace defective parts YES Q212(A102) COLLECTOR 5V operation check YES Replace defective parts YES NO A A - 2-4 - AUX JK601 signal input check IC401 9,36PIN signal input check YES YES MIC IC401 1PIN input check Refer to IC404 Toublesh

38、ooting YES YES TUNER Refer to TUNERMODULE IC401 6,39PIN signal input check YES YES CD Check Cn601 1,3PIN signal anad Refer to CD Troubleshooting IC601 8,3PIN signal input check YES YES MAIN PCB PATTERN check NO B - 2-5 - IC301 Troubleshooting MIC PCB IC406 6PIN power check and 2PIN input check YES M

39、IC input pattern disconnection check and after MIC insertion NO IC406 7PIN output check YESMIC MUTE operation status check NO PN401 3PIN output check YES NORMAL YES IC406 7PIN output check NO Replace IC406 NO Check PN401 connection status and IC301 20PIN status check NO JK401 input check Q302 collec

40、tor HIGH operation check Q302 (Replace C102) IC301 17,46,72,90 power impression check SMPS power 5V check YES NO PN301 20PIN 5V impression chck PN301 4PIN 5V P-SENS terminal check YES NO X301 ossillates or not? Replace X301 YES NO When IC301 11PIN power insert High LOW High Replace IC301 Reset circu

41、it check YES NO Q302(C102M) operation staus check NORMAL YES YES NO B - 2-6 - IC401 (NJW1190) Troubleshooting IC401 24PIN power impression check Refer to SMPS power check YES NO IC401 22,23 Pulse waveform check (VOL UP,DOWN check while rotating VOL UP, DOWN IC401 20,25 PIN waveform output check IC30

42、1 10,8PIN check IC401 7,37PIN(TAPE) input waveform check YES YES YES YES NO Replace IC601 NO IC401 6,39(TUNER) PIN input waveform check TAPE Troubleshooting NO IC401 8,37(CD) PIN input waveform check TUNER module replacement NO YES NO IC401 9, 36(AUXO input waveform check CD Troubleshooting Nomal Re

43、place IC401 NO MICOM(10,8) - IC601(21,22) PATTERN check YES IC301 Troubleshooting NO IC302, 202 (BU2090) Troubleshooting IC301, 201 16PIN power impression check SMPS power check YES NO IC302,202 95,2,3PIN CLK data check CONTROL function check IC301 95,34,4PIN data check(When switching CD, TAPE FUNCT

44、ION) NORMAL YES YES NO Replace IC302, 202 NO Pattern check between IC301 and IC501 YES Refer to IC301 Troubleshooting NO - 2-7 - AMP MODULE Troubleshooting PN301, PN702 assembly status check 1. PN301(7,8), PN702(13,14) PWM DATA.CLK operation status check, PN301 PWm/CS534012PIN 5152.514214 RESET 14 c

45、heck 2. PN702:13PWM_SDA, 14PWM_SCL 1.5152.5142/RESET check YES NO YES NO PN 7PIN 3.3V check power check 12.288MHz oscillation check 11, 27, 46PIN 3.3V check YES YES YES YES YES SMPS power check CS5340 2PIN MCLK/PS9813 48CLK_IN Replace when 12.288 is defective NO IC702 41, 42, 43, 44 operation status

46、 check SMPS power check NO IC703 power cehck IC703 5,15PIN RESET check NORMAL SMPS 36V power check NO IC301 79,81 PN301 12,14PIn check NO Play check IC201 16PIN VCC power impression IC201 5, 26PIN Signal Output check IC201 14PIN Muting circuit check Refer to SMPS power cehck Replace IC201 Replace De

47、ck Mecha Deck Mecha operation performance check YES YES YES NO NO NO - 2-8 - Rec check (Q252, Q202 ON :R273, R223 High) IC401 11,34 OUT check IC401 each input 6, 39.TAPE. 7, 38. CD 8,38 AUX 9.36PIN signal input check IC201 7,24PIN input check IC201 10,21PIN output check REC input check Input LINE ch

48、eck YES YES YES NO NO L203 2,3PIN oscillation check After REC output check, Replace defective ICYES NO YES NO YES NO YES NO YES NO IC202 14PIN operation status check IC202 4PIN operation check Q205 Base 0.6V impression check YES Q213, 212 operation status check YES DECK replacement YES NO Refer to p

49、ower check Q204 Collector Low IC202 Troubleshooting check Q203 replacement Q204 replacement NORMAL L203 replacement - 2-9 - Dubbing check (“NORMAL or REC”/“HIGH”) IC401 11,34 OUT check IC401 each input TUNER 6, 39 TAPE 7, 38 CD 8, 38 AUX 9, 36 PIN signal input check IC201 7, 24PIN input check IC201 10,21PIN output check REC input check Input LINE check YES YES YES - 2-10 - INTERNAL BLOCK DIAGRAM of ICs TAS5142 BLOCK DIAGRAM System Mircrocontroller /OTW (Over Temperature Warning) /SD (H-Bridge is in shutdown) VALID_AB /RESET_AB PWM_