Vieta-VMD55USB-cs-sm 维修电路原理图.pdf

Service manual?VMD55USB?contents1? Debug element scheme -12? Triode integrated circuit outside drawing -23? Malfunction follow check list -3-4 4? ltems lf safety attention -5-7 5?PCB layout-8-116?Elements layout -12-137?-148?Wiring diagram-159?Exploded view-16-1710?Electronic specification-18-2211?Part list-23-38This service manual is just for your reference(it just contains a little service contents and items of safety attention,And the use of technical service is up to the service level of repairman himself),If any changes we wont inform. RadioFans.CN 收音机爱 好者资料库FM receiver frequency covermedium wave AM frequency coverDEBUG ELEMENT SCHEMELC72130LA18231RadioFans.CN 收音机爱 好者资料库D e b u g e l e m e n t s c h e m e?8050SA7264AT24C02LA18237812LM7805PT6311ICLC72130NE008PT2579TDA2822LM2576PT2314IC ? TRANSISTOR LEAD IDENTIFICATION2T r i o d e i n t e g r a t e d c i r c u i t o u t s i d e d r a w i n gFOLLOW-UP FAULT RECORD CHARTCheck if the sound source (speaker) is good or not?Confirm to change the speaker or output wirenoyesMake sure to change the transformer of power supply and thepower commutate circuit.No sound is heard for radio receptionCheck if the DVD output is good ornot? Check if the radio reception circuit IC 1823 and the componentaround it is regular or not?yesnoCheck the public circuit and power circuit.no Check the radio reception controledcircuityesCheck if the power supply circuit of radio reception isregular or not?noyesyesnoyesCheck if the output public circuit?amplified circuit is good or mtfor the whole unitnoyesCheck if the power supply circuit is good or not?no?yesCheck the amplified integrate circuit 7265 andchange it.Make sure to change the IC 1823 and the componentaround itMake sure to change the concerned component of radioreception controled circuit.nonoyesMake sure to change the concerned component of powersupply circuit?No sound is heard for DVDCheck if the output of radio reception is good or not?Check the public circuit?power circuit and change theconcerned componentCheck if the DVD controled circuit is good or not?Make sure to change the concerned component of DVDcontroled circuitCheck the concemed components?row wire ?socketsof DVD signal channel?Make sure to change the concerned components?rowwire?sockets of DVD .Change the decode board.No sound is heardfor the whole unit.3M a l f u n c t i o n f o l l o w c h e c k l i s tnononononononoyeNo search for DVDCheck if power supply of decode board +3v?+5v isregular or not?Check the stable voltage.Check if the light head component can give out lightregular or not?The decode board isbroken.Check if the light head component row wire is loose ornot?Check and change the betler light head row wire.The lithting head component is broken.No picture for DVDCheck if the audio video socket?video line is regularor not?The decode board is broken.Make sure to change the video line and socket.4M a l f u n c t i o n f o l l o w c h e c k l i s tSAFETY ATTENTION Common Controlling During maintenance, please take common controlling to protect component system and electronic parts and prevent damages to the circuit due to improper operation . led out wire should be kept away from high-pressure or high-temperature parts. MAINENANCE ATTENTION Attention: please read ?SAFETY ATTENTION?carefully. If there are unexpected conflicts between safety attention and maintenance attention, please abide to safety attention: Safety first. Common Maintenance Attention1. Before using, please unplug the power cord of the component system.a. Disassemble any parts the parts of circuit board and other parts.b. Cut-off and re-connecting component machine plug and other inserting parts.c. Abreast electrolysis capacitance and checking parts, Note: anti-polarity and changed wrong will cause explosion.2. dont spray chemical dose on the component system, surroundings and any parts.3. Except other specification of this manual, clean the appliance with a cotton swab of dedicated detergent. Notes: a. It is a kind of inflammable mixing.b.Except other specifications of the manual, soldering point doesnt use lubricant.ES Some semi-conductor parts are easily damaged by static charges, these parts are called: ES are mainly the cores of transistor lead identification. The following technical ways can be used to reduce the damages by static charges.1. Before connecting semi-conductor or the parts. Let off the static charges of the body by connecting the earth. In the other hand, To prevent potential shock hazard, please use industrial static handle before connecting power to the checking equipment.2. After discharging the ES parts, put it on connecting appearance, for example. Aluminium surface preventing accumulating static charges to damage the parts. 3. Only use anti-static charges grounded soldering irons to discharge the parts and connecting ES parts and connecting ES parts.4. Some soldering pads called “Anti-static charges” can also generate charges to damage ES parts.5. Dont use poisonous and caustic agent these chemicals can generate static charges to damage the ES parts.6. KEEP ES components in conductive packages until they are used ( mostly replacing ES components with conductive electronic-plating. metal box or similar conductive materials).7. After taking repaired ES components from Anti-static charges cone, please Insert the ES components to the parts of circuit light now.8. During handling sealed ES components, trying to reduce the movement of the body ( clothes rubbing and moving on the rag can generate static charges to damage the ES parts).Common Soldering rules1. Use only grounded low-voltage soldering irons, and proper size and shape, these will maintain the soldering iron temperature of 230?280?.2. USE RMA specified resin flux, include 60% Tin 40% lead.3. To maintain soldering iron and including tin very well.4. Cl ean the soldering surface, use metal brush to do it, not use poisonous and caustic agent to clean.5. Adopt the melting ways:a.Make soldering iron head to reach normal temperature from 230?280?.b. Heat lead wire of the parts, until soldering pads melt.c.Quickly melt soldering tin by anti-static charges.Notes: Quickly operation, prevent heating the electronic-plating copper.6. Adopt the following soldering technology.a.Make soldering iron head to reach normal temperature from 230?280?.b. Firstly hold the soldering iron and the soldering iron to the led wire of the part, until soldering pads melt.c.Quickly make soldering iron head move forwards led pins of the parts and 5It e m s o f s a f e t y a t t e n t i o nelectro-plating copper.Notes: Quickly operating, avoid heating electronic-plating copper of printed circuit board.d. Check the soldering zone strictly, use iron brush to clean more sprayed soldering tin. ICs discharging changing IC pins inserting chute some printed circuit board. Through chute to insert IC pins will be bolded and flat along electrons-plating copper when the hole is slot you can discharge and change IC.Discharging 1.Flat the discharging IC pins, point the soldering iron head to the pins, make the soldering tin melt.2.Before discharging IC, suck off the loaded solder pads by tin with Anti static charges.Changing 1. Replaced IC is inserted in circuit board carefully.2. Bold each IC pin point the circuit board and solder.3. Clean soldering zone by a small hard brush ( lover protective layer)What items do you need attention on charging IC and chip? Because IC and chip are slim and damaged easily by static charges. Pay attend to the following items when changed.1. Prevent damages for chip parts by heat. dont exposed soldering iron.2. Pre heating soldering iron at about 100?when some parts are easily damages suddenly.3. To prevent some parts heated hurried, soldering iron head temperature from 240?280?.4. Because small parts cant hold too much solder tin, so use small soldering tin 0.3mm soldering. According to the situation, adding soldering.5. Be careful of charging parts, soldering speed should be quick to prevent damages for circuit board.6. To re-connecting well, clean the basic board.7. Prevent tin spray on the board to make printed circuit board short circuit.8. Point the first end to make solder easily.9. To prevent damages for parts and circuit board, please confirm damaged parts.10.During soldering , check the soldering connecting specially for many pins small parts.11.Checking is very important after changing use enlarger soldering leakage ,false soldering, short circuit upper of printed circuit board, breaking. Not touching very well because of soldering.“Small Type” detachable transistor discharge and charging1. Heat the round pins and clean tin of transistor .2. Discharge heat-radiator. Screw it.3. Discharge the heat-radiator from printed circuit board.4. Insert new transistor to the circuit board. 5. Solder each transistor pins and cut/more led wire.6. Re- install the heat-radiator.diode discharge /charging1. Chip the pins of led, better to chip the led, discharging the wrong led.2. Bold two pins. Which are vertical to circuit board.3. Check the polarity of the led, then place led pins into the soldering plate.4. Press the connecting point and solder them.5. Check two soldering points. If not smooth, and more soldering, re-soldering. Electro-plating copper repairs When soldering time is too long , the more heat will upper electronic-plating copper please abide to the following rules and programs. IC connecting electronic-plating copper repairs. Use led wire to solder electronic-plating copper repairing IC connecting electronic-plating copper (only for IC).1. Use sharp knife to scrape the damaged (electronic-plating copper).2. Strip the remind tin soldering agent from reminder.3. Bold the skip wire to be a small “U”, soldering with IC pins.4. Along breaking electronic-plating copper to good electronic-plating copper after soldering, cut the more skip wires.Repairing other electronic-plating copper. Using the following technology to repair other wrong electronic-plating copper including installing 6It e m s o f s a f e t y a t t e n t i o nskip wires on circuit board.1. Use sharp knife to scrape wrong skip wire of electronic-plating copper at least 1/4 inchs copper to ensure once skip wire working.2. From both sides of broken electro-plating copper soldering led wire with the nearest parts along the electronic-plating copper wire.3. Use insulating wire soldering the near two parts (20# wire).Notes: Ensure insulating wires insulation, not happened (to parts or sharp edge).Checking progress of DVD part When the DVD is playing if music continuous unstable or without sound, that means the DVD part is out of order, and it should be checked and repaired. Notes: DVD part checking progress.Discharging laser head need to pay attention In order to prevent the laser head being destroyed by the static charges that came from human body or clothes when it read the laser light led from units, the following measures should be taken when it is discharge:1. To lay a electric blanket on the working desk and pack the exchange parts with black color packing material.2. Put the conducting electric blanket on the conductor base, make the conducting electric blanket in a good earth connecting state.3. Put a head on the conducting electric blanket, make it the same electric potential as the earth.4. Then discharge the laser led and check the unit parts.5. Complete the requirement on the conducting electric blanket. Be careful dont let clothes or other static charges resource touch the laser head parts.6. The conducting electric ring which is on the wrist should be connected with the conducting electric blanket.7. The conducting electric blanket and the working desk that made of copper or other conductor should be properly connected to earth when being used.8. When charging laser head components, printed boards and ends.9. After finishing changed laser head components, should cut off the short circuit s ends.7It e m s o f s a f e t y a t t e n t i o n8PCB t o p p a n e l d i a g r a m9PCB b o t t o m p a n e l d i a g r a m10PCB t o p p a n e l d i a g r a m11PCB b o t t o m p a n e l d i a g r a m1234ABCD4321DCBA3317-Jun-200515:48:18F:My design1302dab.ddb - MCD700PCBT-003.schSIZE:MODEL:DATE:FILE:REV:SheetofTIME:A4drawh by:xiaojiehengApproved by:?checked by:123456789101112131415161718192021222324AM RFREGAM OSCVCC1FM IF OUTGND1IF BUFFSTAMIF OUTFMIF INAMIF INAGCDETST/MOFM/AML OUTR OUTMPXINDET OUTFM OSCVCC2RF OUTGND2RF IN1.21.24.54.52.204.54.54.51.21.20.13.74.54.51.21.21.20.13.74.44.400.9IC3LA1823X-INBO5CEDICLDOBO1BO2BO3BO4IO1IF INIO2AM INFM INVDDAOUT1AIN1PD1PD2AIN2AOUT2VSSX-OUT123456789101112131415161718192021222324IC4LC72130123456T205B BLACKC147PC230PC410uFC53.3uF12345T511812345T303B12345T403BD1SCV220D2SCV220D3I384CF110.7MCF3450JCF210.7MX14.5MC80.22uFC90.33uFC63.3uFC103.3uFC114.7uFC120.47uFC13100uFC14100uFC17100PC22223C26223C23223C18100PC27203C32102C28103C24223C33103C19102C25203C35222C29103C363PC377PC3836PC395PC20102C4036PC30103C41102C31103C42501C34102C4318PC2118PC4415PC347PR147KR7100kR93.3KR10 100R121KR13 1KR19 10KR141KR2010KR22180R2110KR151KR247KR347KR232.2KR24 330R161KR251.5KR27220R261.5KR28220R447KR11100R8100KR17 1KR2910R547KR3010R647KR181KQ19014Q29014ANT1?L110uHL25T5L36T5L46T5DZ25V1DZ15V1C73.3uF1234J1CON412345J2CON5C15100uFC16100uFAM ANTDOCLDICEGND9VR OUTGNDL OUTC48203C47223C45470PC46100uFC49103R362.2KR352.2KC51682C50682R?82KR34100KQ39014R?100K1K12El e m e n t s l a y o u t123456789101112ABCD121110987654321DCBATitleNumberRevisionSizeA1Date:7-Dec-2005 Sheet of File:D:1302bu1302du.DdbDrawn By:123Q1078550R1111K132Q1038050C10347uFR1024K712CN1082.5/2PD1074001Vdd1AGND2TREB-L3TREB-R4R-IN5R-OUT6LOUD-R7AUX-R8VCD-R9TUNER-R10TAPE-R11LOUD-L12AUX-L13VCD-L14TUNER-L15TAPE-L16L-IN17L-OUT18BASSIN-L19BASSOUT-L20BASSIN-R21BASSOUT-R22OUT-R23OUT-L24DGND25SDA26SCL27REF28U104PT2314SDASCLR1351KR1321K123456131581112101416791718192021222324252627282930CN11330PAUX1-LAUX1-RAUX2-RAUX2-LMUTE123CN1063.95/3P+ACAC-D101KBL406F101F4AL250VF102F4AL250VC1012200uF/35VC1022200uF/35V+21V-21V123Q101772R1064K7R10147K132Q1028050R10547KOUTGNDINU103 7812C11547uF/35VC12247uFOUTPUT11+Vs2OUTPUT23MUTE4-Vs5IN26GND7IN18TDA7264U105TDA7264C143683(M)C144683(M)C130 10uF/50VR13415KQ1068050R10915KQ1058050R11547KD1054148AMP-MUTE+21V-21V+12VC145104(M)C157104(M)R1464.7/0.5R1474.7/0.5J104PST-416(UP RED DOWN BLACK)C10922uFC11110uFC11210uFC12610uFC1402.2uFC1412.2uFC1342.2uFC1352.2uFC1362.2uFC1372.2uFC1382.2uFC1392.2uFC12410uFC10747uFR1275K6R1265K6C129104(M)C125104(M)C120104(M)C116104(M)R120270C131104(M)C128104(M)C118272(M)C114272(M)TO FANKEYDDGND12345678CN1112.5/8PR13915/0.5C12310uFC13210uFR13722KR13822KR1406K8+12V1G1234G256J103RCA-4071243L105JKB7525_011234CN1092.0/4PAGND16.5V+16.5V-AGNDV_FAN10V+10V-VF1VF2VF12_0VDDGND21V-21V+1243L104JKB7525_01AGNDAGNDFM_LFM_RCD-LLCD-RR10V+10V-SCLSDAVF1VF2-28VDDGNDAUDIOKEYSTANDBY+12VMUTE_AMPR180120CD-LLCD-RRFM_RFM_LMUTER1814K7R18222KF103F2AL250VNF11IN12OUT13GND4ALCC5Vcc6OUT27IN28NF29U101N