Philips-MCD-755-Service-Manual电路原理图.pdf

Version 1.0MCD7553141 785 32120DVD Micro theatreall versionsPublished by LX 0737 Service Audio Subject to modification© Copyright 2007 Philips Consumer Electronics B.V. Eindhoven, The NetherlandsAll rights reserved. No part of this publication may be reproduced, stored in a retrievalsystem or transmitted, in any form or by any means, electronic, mechanical, photocopying,or otherwise without the prior permission of Philips.Service Aids .1-1Info. about lead-free soldering.1-1Service Instruction .1-1CD Playability Check .2-1.2-3Disassembly digram .3-1.3-5Software version check and upgrading .4-1Block diagram .5-1Wiring diagram .6-1Tuner Boardcircuit diagram .7-1 layout diagram .7-2VFD Board circuit diagram .8-1 layout diagram .8-2CPU Board circuit diagram. .9-1layout diagram .9-2.9-3 AMP Boardcircuit diagram .10-1 layout diagram .10-2.10-3Exploded view diagram .11-1Service partslist .12-1.12-2Commercial partslistTABLE OF CONTENTS1-1Service Tools:Universal Torx driver holder .4822 395 91019Torx bit T10 150mm .4822 395 50456Torx driver set T6-T20 .4822 395 50145Torx driver T10 extended .4822 395 50423Compact Disc:SBC426/426A Test disc 5 + 5A .4822 397 30096SBC442 Audio Burn-in test disc 1kHz .4822 397 30155SBC429 Audio Signals disc .4822 397 30184Dolby Pro-logic Test Disc .4822 395 10216SERVICE AIDSGB WARNINGAll ICs and many other semi-conductors aresusceptible to electrostatic discharges (ESD).Careless handling during repair can reduce lifedrastically.When repairing, make sure that you areconnected with the same potential as the massof the set via a wrist wrap with resistance.Keep components and tools also at thispotential.ESDCLASS 1LASER PRODUCTGBSafety regulations require that the set be restored to its originalcondition and that parts which are identical with those specified,be usedSafety components are marked by the symbol !.Lead freeSet remains closed!Standard repair procedureNYPlay a CD for at least 10 minutesYplayabilityok ?Nplayabilityok ?add Info for customer“SET OK“playabilityok ?YNcheck playabilityNYplayabilityok ?check playabilitycheck playabilityEYE-Patternok ?NYcheck “EYE-Pattern“replace CD DriveLaser currentok ?NYcheck Laser currentCD Drive offsetsok ?NYcheck CD Drive offsetsclean the lenscheck playabilityreturn setCustomer complaint“CD related problem“return setreturn setreplace CD Drivereturn setreplace CD Drivereturn setreplace Signal Processorreturn set“fast“ lens cleaning1234567For flap loaders (= access to CD drive possible) cleaning method 4 is recommended1 - 7 For description - see following pagesCD PLAYABILITY CHECK2 -1 1PLAYABILITY CHECKFor sets which are compatible with CD-RW discsuse CD-RW Printed Audio Disc.7104 099 96611TR 3 (Fingerprint)TR 8 (600µ Black dot) maximum at 01:00 playback of these two tracks without audible disturbanceplaying time for: Fingerprint 10secondsBlack dot from 00:50 to 01:10 jump forward/backward (search) within a reasonable timeFor all other sets use CD-DA SBC 444A.4822 397 30245TR 14 (600µ Black dot) maximum at 01:15TR 19 (Fingerprint)TR 10 (1000µ wedge) playback of all these tracks without audible disturbanceplaying time for: 1000µ wedge 10secondsFingerprint 10secondsBlack dot from 01:05 to 01:25 jump forward/backward (search) within a reasonable time2CUSTOMER INFORMATIONIt is proposed to add an addendum sheet to the set whichinforms the customer that the set has been checkedcarefully - but no fault was found.The problem was obviously caused by a scratched, dirty orcopy-protected CD. In case problems remain, the customeris requested to contact the workshop directly. The lens cleaning (method 3) should be mentioned in theaddendum sheet.The final wording in national language as well as the printingis under responsibility of the Regional Service Organizations.3FAST LENS CLEANING (dry brush)Use lens cleaning CDSBC AC300.9082 100 00043Insert the lens cleaning CD, press PLAY and follow thevoice guide´s instructions on the CD.4LIQUID LENS CLEANINGBecause the material of the lens is synthetic and coatedwith a special anti-reflectivity layer, cleaning must be donewith a non-aggressive cleaning fluid. It is advised to use“Cleaning Solvent B4-No2”, available with codenumber4822 389 10026.The actuator is a very precise mechanical component andmay not be damaged in order to guarantee its full function.Clean the lens gently (dont press too hard) with a soft andclean cotton bud moistened with the special lens cleaner.The direction of cleaning must be in the way as indicated inthe picture below.Before touching the lens it is advised to clean thesurface of the lens by blowing clean air over it.This to avoid that little particles make scratches onthe lens.CD PLAYABILITY CHECK2-25EYE-PATTERN SIGNAL JITTER MEASUREMENTMeasure the signal on the input of the Signal processorusing an analog oscilloscope. Please find the exactmeasuring point in your Service Manual.See below examples of the signal. Amplitude should read atleast 700mVpp using SBC444A.goodbadIf the oscilloscope shows a signal like the bad one, and/orthe amplitude decreases within 1 minute - the CD drive hasto be replaced.6CD DRIVE LASER CURRENT MEASUREMENTThe laser current can be measured as a voltage drop on aresistor. The resistor is marked in every Service Manual.The value depends on the type of CD drive.typical value most probably defectVAMxxxx : 150-230mV 350mVMCDxx : 170-230mV 300mVDA1x : 210-250mV 350mVDA2x : 175-200mV 250mVUse SBC444A (CD-DA) for measurement.7CD DRIVE OFFSET MEASUREMENTThe photodiodes of the CD-drive may have an offset. Theseoffsets have to be compensated by the signal processor.High offsets can lead to poor playability of some CDs(skipping tracks).To measure the offset values, start the Service TestProgram - section “Focus Test” without a CD.The offsets can be measured with a DC Millivoltmeterdirectly on the connector (see drawing below). Pinnumbering varies from drive to drive.The values from diode A-D should read 0±10mV.Diodes E and F are less critical.If one of the offsets is higher than ±10mV the CD drive hasto be replaced. Otherwise replace the Signal Processor.Sanyo DA12T3CD DriveAAFCBECDEVCCBVREFFD9101112131415161800+5V_HFVrefCD10ADEBCFGND 8EDABCFLaser power control100n2878470n287638211R1K3823288033p+5VBC807-407879381747R38204R747R38191n28792877 47u1847811-ALM358D3210K382247R38182841 100n47n2869+5V_HFLASER DIODEU >250mV->Laser damaged !4,6V3V3,3V3,9V2V0,17V0,17VSanyoDA12T3HF-AmplifierD3D2D1Drive detection680R390539033K3BC847B787747n28181K53902574216364891011470R3893+3.3V2K23908 10K3923BC847B7878BC847B78764n728133896100R220u28852881560p47n2887560R39012883470n28174u73n328143898220R389527K470n2884+3.3V3909820R3907100R392033K3897288282p3K339042K738993906470R+5V_HFHFINVrefCD10100p2815281622nLDONto 3826,3827VREF GEVDDA1VRINVSSA1ISLICELDOND1D2D3D4HFINHFREFIREFCD_DA: 0V / CD_RW: 3V (A-D)800mVppTB = 0.5µs/divEYE-PATTERN1,8V1,2V2,4V2,6V0,65VCD PLAYABILITY CHECK2-3MCD755 Disassembly-DVD layer A. Remove bottom cover B.Remove top cover and loosen screws 3×10PTH(4PCS), 3×8FT(2PCS) A1.Loosen screws 2.5×7PWMTT(3PCS),2.6×5PWMTT(7PCS) B1. Loosen screws 3×10FA（ 1PCS） C. Remove side plate and loosen screws 3×6BTH(4PCS),3×6FMTT(2PCS) C1. Loosen screws where is the back of side plank 3×4FMTT(4PCS) Remove bezal panel and loosen screws 3×5FMTT(2PCS) ABB1CC1 Disassembly diagramPage:62D.Loosen screws 3×10PWA(2PCS),3×8PWMTT(2PCS)and then remove mechanism core E.Loosen screws 3×10FA(7PCS),3×6FMTT(1PC),and remove rear plate F. Remove motor and loosen screws where is the front of side plate 3×6FT(2PCS), 3×10BT（ 2PCS） G.Loosen screws 3×6PM(6PCS), remove CPU card and decode card D EF GDisassembly diagramPage:63H. Loosen screws 2×6PWT(2PCS), remove slide plate J.Loosen screws J1 2.6×8PT(7PCS) J2 2.6×5PT(4PCS) J3 2.6×6PT(2PCS), and remove top cover I. Loosen screws2.6×8PT(8PCS), and remove VFD board H I J2 J1 J3 Disassembly diagramPage:64MCD755 Disassembly-AMP layer A.Looen screws2.6×5PWMTT(8PCS), remove plastic bottom cover B. Loosen screws 3×10PTH(6PCS) 3×6BTH(4PCS), remove side plank and top cover C. Loosen screws3×6FMTT(5PCS), remove bezal plank D.Loosen screws 3×12FA(4PCS), 3×10FT(1PC), 3×5FMTT(4PCS), remove rear plank ABC D Disassembly diagramPage:65E. Loosen screws 3×5BM(3PCS), remove connection card F. Loosen screws 3×5BM(4PCS), remove AMP board G. Loosen screws 3×5BM(4PCS), remove power board E F G Disassembly diagramPage:66