LG-LMU5050A-cs-sm 维修电路原理图.pdf

3CD CHANGER HI-FI SYSTEMSERVICE MANUALP/N : 3829RAP006BJULY, 2005MODEL: LM-U2350A, LMS-U2350LM-U4050A, LMS-U4050, LMS-U4050WLM-U5050A, LMS-U5050, LMS-U5050W, LMS-U5050SSERVICE MANUAL MODEL: LM-U2350A, LMS-U2350, LM-U4050A, LMS-U4050, LMS-U4050W, LM-U5050A, LMS-U5050, LMS-U5050W, LMS-U5050SCAUTIONBEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL.RadioFans.CN 收音机爱 好者资料库- 1-1 -CONTENTS SECTION 1. GENERAL SERVICING PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 ESD PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 SPECIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5 SECTION 2. ELECTRICAL SECTION ELECTRICAL TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 INTERNAL BLOCK DIAGRAM of ICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15 SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19 WIREING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-43 PRINTED 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) . . . . . . . . . . . . . . . . . . . . . . . . . .3-3 TAPE DECK MECHANISM (A/R & A/S : LEFT A/S DECK) . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5 CD MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7 SECTION 4. SPEAKER PART SPEAKER PART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 SECTION 5. REPLACEMENT PARTS LIST REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1RadioFans.CN 收音机爱 好者资料库- 1-2 -SECTION 1. GENERAL SERVICING PRECAUTIONSI 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 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 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 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 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 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 cotton 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 fingers or other exposed skin.MagnetHow to hold the pick-upConductive SheetCotton swabPressurePressure- 1-3 -I 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 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, 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 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 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) 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 pick-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 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)ConductiveSheetResistor(1 Mohm)ArmbandRESET jump wireVOLUMEVOLUME KNOBDOWNUP- 1-4 - ESD PRECAUTIONSI 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 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 semiconductor-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 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 to solder or unsolder ESD devices.4. Use only an anti-static solder 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 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 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 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 TRIANGLE, ISINTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED “DAN-GEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OFELECTRIC SHOCK.THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THESERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICELITERATURE.- 1-5 - SPECIFICATIONSGeneralCDTunerAMFM(MW)SpeakersSubwooferTAPEPower supplyRefer to the back panel of the unit.Power consumption200 W110 WWeight8.5 kgExternal dimensions (W x H x D)280 x 370 x 400 mmFrequency response 40 - 18000 HzSignal-to-noise ratio 75 dBDynamic range 70 dBTuning Range87.5 - 108.0 MHz or 65 - 74 MHz, 87.5 - 108.0 MHzIntermediate Frequency10.7 MHzSignal to Noise Ratio60/55 dBFrequency Response60 - 10000 HzTuning Range522 - 1620 kHz or 520 - 1720 kHzIntermediate Frequency450 kHzSignal to Noise Ratio30 dBFrequency Response120 - 2000 Hz Output PowerFront : 270 W + 270 W (LM-U5050 model only)250 W + 250 W (LM-U4050/U2350 model only)Surround : 110 W + 110 W (LM-U5050 model only)Subwoofer : 350 W (LM-U5050/U4050 model only)T.H.D0.7%Frequency Response42 - 20000 HzSignal-to-noise ratio80 dBTape Speed3000 3 % (MTT-111. NORMAL-SPEED)Wow Flutter0.25 % (MTT -111, JIS-WTD)F.F/REW Time120 sec (C-60)Frequency Response125 - 8000 HzSignal to Noise Ratio40 dBChannel Separation50 dB (P/B)/45 dB (R/P)Erase Ratio55dB (MTT-5511)TypeBass Reflex 3Way 3 Speaker Bass Reflex 2Way 2Speaker Impedance6 24 Frequency Response55 - 20000 Hz60 - 20000 HzSound Pressure Level86 dB/W (1m)86 dB/W (1m)Rated Input Power270 W250 W 110 WMax. Input Power540 W500 W 220 WNet Dimensions (W x H x D)250 X 300 X 415 mm 187 X 258 X 415 mmWeight9.3 kg4.3 kgSpeaker NameSubwoofer (LMS-U5050W/U4050W)Type1 Way 1 Speaker Impedance6 Frequency Response45 - 15000 HzSound Pressure Level84 dB/W (1m)Rated Input Power350 WMax. Input Power700 WNet Dimensions (W x H x D)279 X 320 X 415 mmWeight10.0 kgLM-U5050MODELSECTIONLM-U4050LM-U2350AmpFront speaker (L/R)LMS-U5050 LMS-U4050/U2350Surround speaker (L/R)LMS-U5050SSpeaker Name- 1-6 - 2-1 -SECTION 2. ELECTRICAL ELECTRICAL TROUBLESHOOTING GUIDEI SMPS POWER CIRCUITP-SENS PARTVKK CHECKSMPS ASSY CN902 7PIN 5.1V CHECKMAIN PCB CN710 7PIN 5.1V CHECKMAIN PCB CN304 5PIN 5.1VCHECKFRONT PN302 36PIN 5.1VCHECKFRONT IC306(RESET IC)STATE CHECKU-COM IC304 26PIN 5VCHECKSMPS TROUBLESHOOTING CONSULTCN710 CONNECTION STATE CHECKMAIN PCB PATTERN CUTTING ANDSHORT CHECKIC306 INPUTVOLTAGE4V,OUTPUTVOLTAGE.2.1VSTATECHECKIC306 KIA7042 CHANGENONONOYESYESYESYESYESCN710 10PIN DC -33V CHECKIC304 51PIN VOLTAGE CHECKSMPS TROUBLESHOOTING CONSULTNOYES- 2-2 -MICOM (IC301) CHECKP-CTRL CHECKP-SENS CHECKRESET IC304 11 PIN CHECK(HIGH LOW HIGH)X301 VIBRATION SIGNAL CHECKIC301 CHANGEPN302 33 PIN P-CTRL CHECK (HIGH)CN710 5 PIN CHECKSMPS TROUBLESHOOTING CONSULTIC304 VDD(17,46,72,90) PIN VOLTAGECHECKP-SENS TROUBLESHOOTING CONSULTQ303 STATE CHECKTR Q303 CHANGESMPS TROUBLESHOOTING CONSULTMICOM IC304 STATE CHECKSMPS + MAIN BORD-TO-BORD CHECKMAIN CN710 6 PIN CHECKPN302 35 PIN +5.6V(MI) CHECKX301 CHANGENONONONOYESYESYESYESNONOYESYES- 2-3 -MUTING TROUBLESHOOTING (MUTE STATE)EXPEND IC(IC305/501/502) STATEQ752(A102) BASE HIGHQ701, Q751(D1302) BASE HIGHCHECK16 PIN VDD VOLTAGE CHECK3 EXP-CLK CHECK2 EXP-DATA CHECK4 PIN 15 PIN EACH PORT STATECHECKEXPEND IC OKMUTEEXPEND IC(IC305) 5PIN HIGH STATECHECKQ752(A102)STATE CHECKQ752(A102) FAULTY IS CHANGEEACH PART TR CHANGED332/D553/D551(1SS133) CHECKD332/D553/D551(1SS133)CHANGEPCB PATTERN CHECKPCB PATTERN CHECKMICOM (IC304) 4/84/85 PINCHECK(CLK1/2/3)MICOM (IC304) 3 PIN CHECKEXPEND IC FAULTY IS CHANGENONONONONONONONONOYESYESYESYESYESYESYESYESYESYESYESYES- 2-4 -SPECIFIC FUNCTION MODE HAS NO SOUND (NJW1190) IC601IC201 INPUT CHECK(HEADINPUT)ADECK 32,39 BDECK 34,37DECK HEAD WIRECONNECTION STATE CHECKIC502 10PIN(PB MUTE) STATESTATE CHECKIC502 4PIN(REC SW) LOWSTATE RECQ212 (C) HIGH CHECKQ213 (C) LOW CHECKIC502 13 PIN REC-BAIS HIGHCHECKL203(4.7MH) COIL VIBRATIONSIGNAL CHECKIC601 7 /32 INPUT REC SIGNAL CHECKIC502 4PIN(REC SW) HIGHCHECKIC601(NJW1190)TROUBLESHOOTING CONSULTIC502 2 PIN/3 PINCHECK(DATA/CLIC502 16 PIN VDD CHECKIC502 EXPEND IC CHANGEIC201 OUTPUT CHECK(5,26 PIN)IC601 3,36PIN INPUT SIGNAL CHECKIC601 17,22 PIN OUTPUT SIGNALCHECKDECK OUTPUT1)1)YESYESYESYESYESYESYESYESYESYESYESYESNONONONONO- 2-5 -AUXJK601 SIGNALINPUT CHECKIC601 5,34 PIN SIGNALINPUTCHECKIC601 17,22 PIN OUTPUT SIGNALCHECKMAIN PCB PATTERN CHECKIC601(NJW1190)TROUBLESHOOTING CONSULTMAIN PCB PATTERN CHECKIC601(NJW1190)TROUBLESHOOTING CONSULTAUX OUTPUTCDCN709 1,3PIN SIGNALCHECK CDTROUBLESHOOTINGCONSULTIC601 4,35PIN SIGNALINPUTCHECKIC601 17,22 PIN OUTPUT SIGNALCHECKCD OUTPUTYESYESYESYESYESYESYESYESNONONONO- 2-6 -TUNERTU101 3 /5 SIGNAL CHECKIC601 2,37 PIN SIGNALINPUTCHECKIC601 17,22 PIN OUTPUT SIGNALCHECKTU101 2 PIN +9VVOLTAGE CHECKTU101 6,7,8,9 PIN CHECK(PLL-CE, PLL-DI, CLK, PLL-DO)TUNER MODULE CHANGETUNER OUTPUTMICCN303 7 PIN MIC-SIGNAL CHECKIC601 44 PIN SIGNAL CHECK(OW601PATTERN)IC601 17,22 PIN OUTPUT SIGNALCHECKCN303 4 MIC-SENSE CHECKPN400 3 PIN +12VCHECKTR CHANGEMIC MUTE CHECK(Q409/ Q408)IC402 8 PIN SIGNAL INPUT CHECKPN400 9 VOL-INCHECKIC402 2 PIN SIGNAL INPUT CHECKPN400 10 PIN VOL-OUTCHECKMIC OUTPUTYESYESYESYESYESYESYESYESYESYESYESYESNONONONONO- 2-7 -IC601(NJW1190) TROUBLESHOOTINGIC601 24PIN VOLTAGE INPUT CHECKIC601 19,20 SDA, SCA PULSE WAVECHECK (VOL UP, DOWN TURN CHECK)IC601 17.22 PIN WAVE OUTPUT CHECKIC601 OKFUNCTION INPUT PORT SIGNALCHECK(NJW1190 TROUBLESHOOTING)SMPS VOLTAGE CHECK CONSULTIC301 10,8PIN CHECKIC301 TROUBLESHOOTINGIC601 CHANGENONONOYESYESYESYESYESYESYESYESYESAMP MODULE TROUBLESHOOTINGIC501 9 PIN(AMP-PWR)HIGH CHECKEXPEND IC TROUBLESHOOTING CONSULTPROTECTION HIGH SMPS VOLTAGEAND AMP ON/ OFF STATE CHECKAMP MODULE CHECK : MOS FET BOTHARE READ SHORT AMP DEADAMP MODULE CHANGEIC305 9 PIN(AMP-PWR) HIGH CHECKIC701 11 PIN AMP-ON/OFF HIGHCHECKIC701 12 PIN PROTECTION LOWCHECKPN702 3 PIN PROTECTIONCHECK(HIGH LOW)NONONOIC701 3 ,20 & 5 ,18 EACH +65V &-65VCHECKSMPS TROUBLESHOOTING CONSULTYESNO- 2-8 -IC701 9 ,14 9V CHECKIC701 10 , 13 INPUT SIGNAL CHECKIC701 5 ,17 OUTPUT SIGNAL CHECKOKSMPS TROUBLESHOOTING CONSULTREC INPUTCHECK CHECKINPUT LINE CHECKIC202 4PIN STATECHECKQ205 BASE 0.6V CHECKVOLTAGE CHECK CONSULTIC202 TROUBLESHOOTING CHECKQ204 CHANGEL203 CHANGEQ204 COLLECTOR LOWQ203 CHANGEOKREC OUTPUTCHECK AFTER FAULTY IS ICCHANGEYESYESYESYESYESYESYESYESYESYESNOREC CHECK (Q252,Q202 ON :R273