LG-LMU1350-cs-sm 维修电路原理图.pdf

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1、3CD CHANGERDVD KARAOKE SYSTEMSERVICE MANUALMODEL: LM-U1350A, LM-U1350D, LM-U1350X, LMS-U1350 SERVICE MANUAL MODEL: LM-U1350A, LM-U1350D, LM-U1350X, LMS-U1350RadioFans.CN 收音机爱 好者资料库- 1-1 -CONTENTS SECTION 1. GENERAL SERVICING PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2、 . . . . . . . . . . . . . . . 1-2 ESD PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5 SECTION 2

3、. ELECTRICAL SECTION TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 AUDIO PART TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 BLOCK DIAGRAM . . . . . . . . . . . . . . .

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

5、 . . . . . . . . . . . . . 2-43 PRINTED CIRCUIT DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-45 SECTION 3. EXPLODED VIEWS CABINET AND MAIN FRAME SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1 TAPE DECK ME

6、CHANISM (A/R & A/S : RIGHT A/R DECK) . . . . . . . . . . . . . . . . . . . . . . . . .3-3 TAPE DECK MECHANISM (A/R & A/S : LEFT A/S DECK) . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5 CD MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7、. . . . . . . . . . .3-7 SECTION 4. SPEAKER PART SPEAKER PART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 SECTION 5. REPLACEMENT PARTS LIST REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8、. . . . . . . . . . . . . . . . .5-1RadioFans.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 exte

9、rnal pressure or impact.2. Repair notes1) 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 andimpact. If it is subjected to strong pressure or i

10、mpact, the result may be an operational malfunction 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 ma

11、y 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 surfaceIf there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as

12、 usedfor camera lens).The lens is held by a delicate 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 c

13、otton swab. (Donot use any other liquid cleaners, 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 finge

14、rs or other exposed skin.MagnetHow to hold the 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

15、 to, and easily affected by, static electricity. 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, t

16、o 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 repair1) Before replacing a component part, first disconnect the power supply lead wire from the unit2) All equipment, measuring instruments and tool

17、s 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 isbecause there is the possibility of damage by static electricity.)4) To prevent AC leakage, the metal part

18、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 armband.7) The laser beam from the pi

19、ck-up should NEVER be directly facing the eyes 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

20、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 power cord.Resistor(1 Mohm)ConductiveSheetRe

21、sistor(1 Mohm)ArmbandRESET jump wireVOLUMEVOLUME 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

22、typical ESD devices are integratedcircuits and 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 semiconduc

23、tor-equipped assembly, drain offany electrostatic 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 re

24、moving 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 to solder or unsolder ESD devices.4. Use only an anti-static solde

25、r removal device. Some solder removal devices 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

26、 protective package until immediately before 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

27、 replacement ESD device, touch theprotective 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

28、 devices. (Otherwise harmless motionsuch 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. GRAPHIC SYMBOLSTHE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TR

29、IANGLE, IS INTENDED TOALERT THE SERVICE PERSONNEL 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

30、 SAFETY INFORMATION IN SERVICE LITERATURE.- 1-5 - 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

31、 5PIN 5VMAIN PCB CN301 4PN 5V checkRefer to SMPS 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 vo

32、ltage 4V or higer, output voltage2.1V or higer 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 ch

33、eckReplace when Q603(A102) is defectivec-COM 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 sp

34、ecificationYESNOIC601 input check (22/23PIN)c-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

35、-COM 301 3.4PIN CLK/DATA operation checkDECK 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)IC

36、401 7, 38 signal input checkYESNOReplace IC202YESNOQ212(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

37、checkIC401 9,36PIN signal input checkYESYESMICIC401 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 -IC30

38、1 TroubleshootingMIC PCBIC406 6PIN power check 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 I

39、C301 20PIN status checkNOJK401 input checkQ302 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 H

40、igh LOW HighReplace IC301Reset circuit checkYESNOQ302(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 wavefo

41、rm output checkIC301 10,8PIN checkIC401 7,37PIN(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 TroubleshootingNomalRep

42、lace IC401NOMICOM(10,8) - IC601(21,22) PATTERN 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)NORMALYESY

43、ESNOReplace IC302, 202NOPattern check between 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, 14PW

44、M_SCL 1.5152.5142/RESET checkYESNOYESNOPN 7PIN 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

45、 5,15PIN RESET checkNORMALSMPS 36V power checkNOIC301 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-

46、 2-8 -Rec check (Q252, Q202 ON :R273, R223 High)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 d

47、efective ICYESNOYESNOYESNOYESNOYESNOIC202 14PIN 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 replac

48、ement- 2-9 -Dubbing check (“NORMAL or REC”/“HIGH”)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 DIAG

49、RAM SystemMircrocontroller/OTW (Over Temperature 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 supplyDecoupling31V1

50、2VBootstrap4 ohm4 ohmL-C OutputFilter foreach 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