LG-LMSU1050-cs-sm 维修电路原理图.pdf

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1、3CD CHANGERDVD KARAOKE SYSTEMSERVICE MANUALMODEL: 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 PRECAU

2、TIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5 SECTION 2. ELECTRICAL SECTION TROUBLESHOOTING GUIDE .

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

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

5、IT 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. SPEAKER P

7、ART SPEAKER PART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 SECTION 5. REPLACEMENT PARTS LIST REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1RadioFans

8、.CN 收音机爱 好者资料库- 1-2 - SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP1. Notes for transport and storage1) 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 notes1) The

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

10、nction and/ordamage to the printed-circuit board.3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reasonthe adjustment point and installation screws should absolutely never be touched.4) Laser beams may damage the eyes!Absolutely never permit las

11、er 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 surfaceIf there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as usedfor camera lens).The lens is held by a d

12、elicate spring. When cleaning the lens surface, therefore, a cottonswab 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. (Donot use any other liquid clean

13、ers, because they will damage the lens.) Take care not to use too much ofthis alcohol on the swab, and do not allow the alcohol to get inside the pick-up.Storage in conductive bagDrop impactNEVER look directly at the laser beam, and dont let contact fingers or other exposed skin.MagnetHow to hold th

14、e pick-upConductive SheetCotton swabPressurePressureSECTION 1. GENERAL- 1-3 - NOTES REGARDING COMPACT DISC PLAYER REPAIRS1. Preparations1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode).These componentsare sensitive to, and easily affected by, static electrici

15、ty. If such static electricity is high voltage, componentscan 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 betaken, therefore, to avoid repair or storage where the temperatu

16、re of humidity is high, where strong magnet-ism is present, or where there is excessive dust.2. Notes for repair1) Before replacing a component part, first disconnect the power supply lead wire from the unit2) All equipment, measuring instruments and tools must be grounded.3) The workbench should be

17、 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 isbecause 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) W

18、orkers 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 armband.7) The laser beam from the pick-up should NEVER be directly facing the eye

19、s or bare skin.CLEARING MALFUNCTIONYou 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 the inside ofthe volume knob for more than 3 seconds.If you reset your unit, you mu

20、st 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 power cord.Resistor(1 Mohm)ConductiveSheetResistor(1 Mohm)ArmbandRESET jump wireVOLUMEVOL

21、UME KNOBDOWNUP- 1-4 - ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD)Some semiconductor (solid state) devices can be damaged easily by static electricity. Such componentscommonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integratedcircuits an

22、d some field-effect transistors and semiconductor chip components.The following techniques shouldbe 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 offany electrost

23、atic charge on your body by touching a known earth ground. Alternatively, obtain and wear acommercially available discharging wrist strap device, which should be removed for potential shock reasonsprior to applying power to the unit under test.2. After removing an electrical assembly equipped with E

24、SD 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 to solder or unsolder ESD devices.4. Use only an anti-static solder removal device. Some solder removal devices

25、 not classified as anti-static cangenerate electrical charges sufficient to damage ESD devices.5. Do not use freon-propelled chemicals.These can generate electrical charges sufficient to damage ESDdevices.6. Do not remove a replacement ESD device from its protective package until immediately before

26、you areready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together byconductive foam, aluminum foil or comparable conductive materials).7. Immediately before removing the protective material from the leads of a replacement ESD device, touch theprotective

27、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 ALLOTHER SAFETY PRECAUTIONS.8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motionsuch as t

28、he 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. GRAPHIC SYMBOLSTHE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TOALERT THE SERVICE PERSO

29、NNEL TO THE PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” THATMAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PER-SONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.- 1

30、-5 - SPECIFICATIONSNOTE : Specification are subject to change without notice in the course of product improvement.- 1-6 - 2-1 -VKK CHECKP-SENS PART CHECKCN701 3PIN DC -33V checkIC301 51PIN voltage checkSMPS Assy CN904 5PIN 5V operation checkMAIN PCB CN701 5PIN 5VMAIN PCB CN301 4PN 5V checkRefer to S

31、MPS TroubleshootingRefer to SMPS TroubleshootingCN701 contact condition checkMAIN PCB PATTERN disconnection check TROUBLESHOOTING GUIDEYESYESNONOFRONT PN301 4PIN 5V checkFRONT IC304 operation status checcku-COM 26PIN 5V checkYESYESYESYESYESYESNONOInput voltage 4V or higer, output voltage2.1V or hige

32、r operation checkIC304 KIA7042 replacementSECTION 2. ELECTRICAL- 2-2 -Muting circuit Troublrshooting (MUTE condition)Q752(A102) Base “HIGH”Q604, Q605(D1302) BASE “HIGH” checkc-COM operation status checkReplace each related TRQ603(A102) operation status checkReplace when Q603(A102) is defectivec-COM

33、2PIN(A-MUTE) LINE checkCN942/CN701 connection statuscheckMUTEYESYESYESYESNONONOUnfelt voiceInput check (AUX 9.36 TUNER 6/39 TAPE 7/38CD 8/37PIN)Check input and operation status for each functionYESNOIC601 20/25PIN output checkRefer to IC401(NJW1190) IC specificationYESNOIC601 input check (22/23PIN)c

34、-COM check and (CLK/DATA check)YESNOIC601 output check (24PIN)NORMALCheck IC401 24PIN cover 8V and power circuitYESNOPower operation staus checkR634 180(9.1)V checkYESYESNO- 2-3 -Specific FUNCTION MODE unfelt voiceTAPEIC202 9PIN (PB MUTE) operation checkc-COM 301 3.4PIN CLK/DATA operation checkDECK

35、HEAD WIRE connection status checkRefer to IC201 Troubleshooting IC201 input check (HAED input) “A”DECK 32,39 “B”DECK 34,37YESYESNOIC202 14PIN HIGH operation checkQ212(A102) BASE LOW checkQ201.202(GATE) HIGH operation checkNOIC201 output check (5, 26PIN)IC401 7, 38 signal input checkYESNOReplace IC20

36、2YESNOQ212(A101) EMITTER 5V checkQ213(C103 COLLECTOP LOW) operation checkReplace Q213(C103)YESNOYESQ201,202 (DRAIN) GND checkYESReplace defective partsYESQ212(A102) COLLECTOR 5V operation checkYESReplace defective partsYESNOAA- 2-4 -AUXJK601 signal input checkIC401 9,36PIN signal input checkYESYESMI

37、CIC401 1PIN input checkRefer to IC404 Toubleshooting YESYESTUNERRefer to TUNERMODULEIC401 6,39PIN signal input checkYESYESCDCheck Cn601 1,3PIN signal anad Refer to CD TroubleshootingIC601 8,3PIN signal input checkYESYESMAIN PCB PATTERN checkNOB- 2-5 -IC301 TroubleshootingMIC PCBIC406 6PIN power chec

38、k and 2PIN input checkYESMIC input pattern disconnection check andafter MIC insertionNOIC406 7PIN output checkYESMIC MUTE operation status checkNOPN401 3PIN output checkYESNORMALYESIC406 7PIN output checkNOReplace IC406NOCheck PN401 connection statusand IC301 20PIN status checkNOJK401 input checkQ30

39、2 collector HIGH operationcheckQ302 (Replace C102)IC301 17,46,72,90 power impression checkSMPS power 5V checkYESNOPN301 20PIN 5V impression chckPN301 4PIN 5V P-SENS terminal checkYESNOX301 ossillates or not?Replace X301YESNOWhen IC301 11PIN power insert High LOW HighReplace IC301Reset circuit checkY

40、ESNOQ302(C102M) operation staus checkNORMALYESYESNOB- 2-6 -IC401 (NJW1190) TroubleshootingIC401 24PIN power impression checkRefer to SMPS power checkYESNOIC401 22,23 Pulse waveform check (VOL UP,DOWN check while rotating VOL UP, DOWNIC401 20,25 PIN waveform output checkIC301 10,8PIN checkIC401 7,37P

41、IN(TAPE) input waveform checkYESYESYESYESNOReplace IC601NOIC401 6,39(TUNER) PIN input waveform checkTAPE TroubleshootingNOIC401 8,37(CD) PIN input waveform checkTUNER module replacementNOYESNOIC401 9, 36(AUXO input waveform checkCD TroubleshootingNomalReplace IC401NOMICOM(10,8) - IC601(21,22) PATTER

42、N checkYESIC301 TroubleshootingNOIC302, 202 (BU2090) TroubleshootingIC301, 201 16PIN power impression checkSMPS power checkYESNOIC302,202 95,2,3PIN CLK data checkCONTROL function checkIC301 95,34,4PIN data check(When switching CD, TAPE FUNCTION)NORMALYESYESNOReplace IC302, 202NOPattern check between

43、 IC301 and IC501YESRefer to IC301 Troubleshooting NO- 2-7 -AMP MODULE TroubleshootingPN301, PN702 assembly status check1. PN301(7,8), PN702(13,14) PWM DATA.CLK operation status check, PN301PWm/CS534012PIN 5152.514214 RESET 14 check2. PN702:13PWM_SDA, 14PWM_SCL 1.5152.5142/RESET checkYESNOYESNOPN 7PI

44、N 3.3V check power check12.288MHz oscillation check11, 27, 46PIN 3.3V checkYESYESYESYESYESSMPS power checkCS5340 2PIN MCLK/PS9813 48CLK_INReplace when 12.288 is defectiveNOIC702 41, 42, 43, 44 operation status checkSMPS power checkNOIC703 power cehckIC703 5,15PIN RESET checkNORMALSMPS 36V power chec

45、kNOIC301 79,81 PN301 12,14PIn checkNOPlay checkIC201 16PIN VCC power impressionIC201 5, 26PIN Signal Output checkIC201 14PIN Muting circuit checkRefer to SMPS power cehckReplace IC201Replace Deck MechaDeck Mecha operation performance checkYESYESYESNONONO- 2-8 -Rec check (Q252, Q202 ON :R273, R223 Hi

46、gh)IC401 11,34 OUT checkIC401 each input 6, 39.TAPE. 7, 38. CD 8,38 AUX9.36PIN signal input checkIC201 7,24PIN input checkIC201 10,21PIN output checkREC input checkInput LINE checkYESYESYESNONOL203 2,3PIN oscillation checkAfter REC output check, Replace defective ICYESNOYESNOYESNOYESNOYESNOIC202 14P

47、IN operation status checkIC202 4PIN operation checkQ205 Base 0.6V impression checkYESQ213, 212 operation status checkYESDECK replacementYESNORefer to power checkQ204 Collector LowIC202 Troubleshooting checkQ203 replacementQ204 replacementNORMALL203 replacement- 2-9 -Dubbing check (“NORMAL or REC”/“H

48、IGH”)IC401 11,34 OUT checkIC401 each input TUNER 6, 39 TAPE 7, 38 CD 8, 38 AUX9, 36 PIN signal input checkIC201 7, 24PIN input checkIC201 10,21PIN output checkREC input checkInput LINE checkYESYESYES- 2-10 - INTERNAL BLOCK DIAGRAM of ICs TAS5142BLOCK DIAGRAM SystemMircrocontroller/OTW (Over Temperat

49、ure Warning)/SD (H-Bridge is in shutdown)VALID_AB/RESET_ABPWM_APWM_B2-Channel H-BRIDGEBTL ModelVALID_CDPWM_CPWM_DM1M2PVDD(0-31V)GNDGV DD(12V) & VDD(12V)SYTEM POWERHardwireover-curentlimitPVDDPower supplyDecouplingGVDD, VDD,& VREGpower supplyDecoupling31V12VBootstrap4 ohm4 ohmL-C OutputFilter foreach

50、 1/2Bridge2nd OrderL-C outputFilter foreach 1/2BridgeOUT_ABST_ABST_BOUT_BOUT_COUT_DBST_CBST_DBootstrapCapsH-Bridge2/SD/OTWOutputH-Bridge1PVDD_A, B, C, DGND_A, B, C, DGVDD_A, B, C, DVREGAGNDOC_ADJLeftChannelOutputRightChannelOutputTAS50XXHardwireMode444- 2-11 - HA12237FBLOCK DIAGRAM - 2-12 - CS5340BL