Sharp LC-20B2UA Service Manual

Lcd color television

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Service manual (60 pages)

Operation manual (46 pages)

Operation manual (45 pages)

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Page 1: Table Of Contents
OUTLINE The 20" LCD panel used in the LC-20B2UA has been redesigned as from the April production. Accordingly, the circuitry and the adjustment procedures have been partially changed.
Page 2: Important Service Safety Precaution
LC-20B2UA LC-20B2UB IMPORTANT SERVICE SAFETY PRECAUTION Ë Service work should be perfomed only by qualified service technicians who are thor- oughly familiar with all safety checks and the servicing guidelines which follow: ground, such as electrical conduit or electrical ground WARNING connected to an earth ground.
Page 3 LC-20B2UA LC-20B2UB PRECAUTIONS A PRENDRE LORS DE LA REPARATION Ë Ne peut effectuer la réparation qu' un technicien spécialisé qui s'est parfaitement accoutumé à toute vérification de sécurité et aux conseils suivants. conduite électrique ou une prise de terre branchée à...
Page 4 LC-20B2UA LC-20B2UB Precautions for using lead-free solder 1 Employing lead-free solder "Digital PWB" of this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on the PWBs and service manuals. The alphabetical character following LF shows the type of lead-free solder.
Page 5: Specifications
LC-20B2UA LC-20B2UB Specifications Items LC-20B2UA/B Model LCD panel 19.7” TFT LCD Number of dots 921,600 dots VGA Video color systems N358, N443, PAL, PAL-M, PAL-N, SECAM, PAL-60 Destination USA/Latin A/Twn TV Standard (CCIR) NTSC/PAL-M/PAL-N TV function TV Tuning System PLL 181 ch.
Page 6: Operation Manual
LC-20B2UA LC-20B2UB Operation Manual...
Page 7 LC-20B2UA LC-20B2UB...
Page 8: Dimensions
LC-20B2UA LC-20B2UB Dimensions /630 /403 /379 /107.3 /72.6 VIDEO AV-IN1 AUDIO VIDEO AV-IN2/OUT S-VIDEO AUDIO COMPONENT H E A D PHONE ANT. AUDIO POWER INPUT DC13V /60.8 /229.4 (Unit: inch/mm)
Page 9: Removing Of Major Parts
LC-20B2UA LC-20B2UB REMOVING OF MAJOR PARTS 1. Remove the two back covers. 2. Remove the table stand fixing screws (4 pcs.). 3. Remove the rear cabinet fixing screws (14 pcs.) and detach the cabinet. : XBBSF30P06000, : XEBSF40P16000) 4. Remove the reinforcement angle fixing screws (4 pcs.).
Page 10 LC-20B2UA LC-20B2UB 6. Remove the digital PWB fixing screws (3 pcs.). 7. Remove the inverter-A PWB fixing screws (2 pcs.). 8. Remove the inverter-B PWB fixing screws (1 pc.). 9. Detach the chassis frame cover. 10. Remove the analog PWB fixing screws (3 pcs.).
Page 11 LC-20B2UA LC-20B2UB » Precautions in handling the LCD panels 1. Work in a clean room (with humidities below 50%). 2. Be sure to wear an anti-static armband. 3. Handle the panels on an electroconductive mat. 4. Be careful not to fall, shake and shock the panels.
Page 12: Adjusting Procedure Of Each Section
LC-20B2UA LC-20B2UB ADJUSTING PROCEDURE OF EACH SECTION The best adjustment is made before shipping. If any position deviation is found or after part replace is performed, adjust as follows. 1. Preparation for Adjustments (1)Use the exclusive-use AC adapter or stable DC power supply.
Page 13 LC-20B2UA LC-20B2UB 4. Adjustments Adjustment Adjusting conditions Adjusting method 1. Adjust the "B+ Adj" value to 1. Connect the DC voltmeter to B+ Adjustment pin 2 of P3702. 5.0±0.02V with R3760. Make exact (R3760) adjustment of the 5.00V level be- cause it will be the reference for all the other supply voltages.
Page 14 LC-20B2UA LC-20B2UB Adjustment Adjusting conditions Adjusting method 1. Call up the adjustment process menu If the wrong data has been sent: PROM data write and get Page 6 displayed onscreen. 1. Initialize the E PROM. (Take the 2. Enter “A40000002681” for the “I2C special mode setting procedure (1).)
Page 15 LC-20B2UA LC-20B2UB Test patterns in adjustment process mode [1] IC801 (Video decoder) test patterns 1-1. Getting the test patterns displayed Put the screen in AV1, AV2 or COMPONENT but keep out any signal. Call the adjustment process mode, select “TEST PATTERN” in the 3rd line of page 7, make the settings 1 thru 6, and the following test patterns show up.
Page 16 LC-20B2UA LC-20B2UB Pin functions of microprocessor IC (IC2001) RH-iXA154WJZZQ Pin name Function Pin name Function V HOLD Closed caption Adjustment process Closed caption AV/SY/DY2 US CCD input select MAIN SW FSMUTE Main switch ON[H]/OFF[L] Front mute TIMELED RSMUTE Off timer LED light-up...
Page 17 LC-20B2UA LC-20B2UB Adjustment process mode menus at a glance Page Item Initial setting Function Adjust/modify Basic settings INCH SIZE Inch unit select Adjustment MODEL B2UA Model number SYSTEM N358 Color system select NTSC PWN FREQ Dimmer frequency setting PAL PWM FREQ...
Page 18 LC-20B2UA LC-20B2UB Page Item Initial setting Function Adjust/modify Video adjustments (VPC settings) I2C DATA C bus control IC data write & read I2C DATA WAIT Write & read execution Chroma band pass setting NOSEL Comb filter setting Comb filter setting...
Page 19 LC-20B2UA LC-20B2UB Page Item Initial setting Function Adjust/modify Video adjustments (TV, composite & S video) PAL AV COLOR 2500 Color density setting (composite, S video) PAL AV TINT Color tone setting (composite, S video) PAL BRIGHTNESS Brightness setting (TV, composite, S video)
Page 20 LC-20B2UA LC-20B2UB Page Item Initial setting Function Adjust/modify Search AFT reference settings & LCD controller settings (NTSC) AFT UP AFT reference voltage AFT DOWN AFT reference voltage NTSC 01 Initial settings NTSC 02 Various settings NTSC 03 RCUTOFF NTSC 04...
Page 21 LC-20B2UA LC-20B2UB Page Item Initial setting Function Adjust/modify Gradation & COM settings V255 Gradation power reference voltage V255 BIAS Gradation power reference voltage V235 Gradation power reference voltage V235 BIAS Gradation power reference voltage V176 Gradation power reference voltage Change it to "130".
Page 22: Trouble Shooting Table
LC-20B2UA LC-20B2UB TROUBLE SHOOTING TABLE...
Page 23 LC-20B2UA LC-20B2UB TROUBLE SHOOTING TABLE (Continued)
Page 24 LC-20B2UA LC-20B2UB TROUBLE SHOOTING TABLE (Continued)
Page 25 LC-20B2UA LC-20B2UB TROUBLE SHOOTING TABLE (Continued)
Page 26: Chassis Layout
LC-20B2UA LC-20B2UB CHASSIS LAYOUT CONTROL Unit DIGITAL Unit ANALOG Unit RC/LED Unit...
Page 27 LC-20B2UA LC-20B2UB INVERTER-A Unit INVERTER-B Unit...
Page 28: Block Diagram
LC-20B2UA LC-20B2UB BLOCK DIAGRAM ANALOG UNIT TV-V TUNER TU3201 SIF-AMP. Q3201 Q3202 SY, SC S-VIDEO L1, R1 INPUT V2/VO TV-V VIDEO SWITCH AUDIO VIDEO L2, R2 IC402 INPUT IN/OUT IN/OUT OUTPUT SWITCH SWITCH VOUT IC3501 Q3501-Q3505 Q3500 6d B AMP.
Page 29 LC-20B2UA LC-20B2UB DIGITAL UNIT Y and C 3D Y/C REGULATOR SYOUT, SCOUT YO, CO SWITCH SEPARATOR IC7102 IC7101 IC7001 IC7701 IC7002 V1SY,V1SC RESET IC7004 SY, SC VIDEO DECODER AV1 V (VPC) IC801 V1SY CONTROLLER VOUT IC1201 VIDEO SWITCH AMP. IC7202...
Page 30: Description Of Schematic Diagram
LC-20B2UA LC-20B2UB DESCRIPTION OF SCHEMATIC DIAGRAM VOLTAGE MEASUREMENT CONDITION: CAUTION: 1. The voltages at test points are measured on This circuit diagram is original one, therefore there may be a exclusive AC adaptor and the stble supply voltage slight difference from yours.
Page 31: Schematic Diagramë Control And Rc/Led Unit
LC-20B2UA LC-20B2UB SCHEMATIC DIAGRAM Ë CONTROL and RC/LED Unit...
Page 32: Ë Digital Unit
LC-20B2UA LC-20B2UB Ë DIGITAL Unit-1/5...
Page 33 LC-20B2UA LC-20B2UB...
Page 34 LC-20B2UA LC-20B2UB Ë DIGITAL Unit-2/5...
Page 35 LC-20B2UA LC-20B2UB...
Page 36 LC-20B2UA LC-20B2UB Ë DIGITAL Unit-3/5...
Page 37 LC-20B2UA LC-20B2UB...
Page 38 LC-20B2UA LC-20B2UB Ë DIGITAL Unit-4/5...
Page 39 LC-20B2UA LC-20B2UB...
Page 40 LC-20B2UA LC-20B2UB Ë DIGITAL Unit-5/5...
Page 41 LC-20B2UA LC-20B2UB...
Page 42: Ë Analog Unit
LC-20B2UA LC-20B2UB Ë ANALOG Unit-1/2...
Page 43 LC-20B2UA LC-20B2UB...
Page 44 LC-20B2UA LC-20B2UB Ë ANALOG Unit-2/2...
Page 45 LC-20B2UA LC-20B2UB...
Page 46: Ë Inverter-A Unit
LC-20B2UA LC-20B2UB Ë INVERTER-A Unit...
Page 47: Ë Inverter-B Unit
LC-20B2UA LC-20B2UB Ë INVERTER-B Unit...
Page 48: Printed Wiring Board Assemblies
LC-20B2UA LC-20B2UB PRINTED WIRING BOARD ASSEMBLIES CONTROL Unit (Side-A) DIGITAL Unit (Side-A)
Page 49 LC-20B2UA LC-20B2UB CONTROL Unit (Side-B) DIGITAL Unit (Side-B)
Page 50 LC-20B2UA LC-20B2UB INVERTER-A Unit (Side-A) INVERTER-B Unit (Side-A) RC/LED Unit (Side-A)
Page 51 LC-20B2UA LC-20B2UB ANALOG Unit (Side-A)
Page 52 LC-20B2UA LC-20B2UB C701 P2003 D701 P2004 C702 R714 R705 C7104 Q2005 Q2006 R2057 R2024 R419 C409 C414 R415 R2033 R2062 L402 C408 C413 R414 L401 C411 C2020 R2055 R422 C412 R416 FB7105 R2026 R2036 R425 R2044 R2045 IC2001 FL401 R2017...
Page 53 LC-20B2UA LC-20B2UB P2003 C908 R1247 R712 C1208 R2060 C1217 L901 R2057 R2068 R1018 C1228 R2062 D1206 D1205 C1234 R2054 R2002 IC2001 R1257 R2063 R2028 R1258 R2031 R2032 R2051 R2011 C909 C821 R2029 P2001 C1205 R918 R916 C826 R1223 R1218 C706...
Page 54 LC-20B2UA LC-20B2UB D1211 D902 FB903 FB901 IC901 R1237 R1239 R911 R1249 R1248 R1240 D1209 D901 R910 Q1204 R1230 R1251 R1250 TP2005 C1233 R2059 IC2004 IC2002 R1225 R1254 TP2003 R2058 C840 C812 R2016 C1204 R831 R1256 R812 R837 R838 C810 IC2003...
Page 55 LC-20B2UA LC-20B2UB IC703 R715 R2066 D2005 R2065 R2064 R2052 R2049 TP2001 R2003 TP2002 TP2006 R2030 R413 TP2007 TP2009 IC2002 R407 R411 FB7102 TP2003 R406 R7113 C2002 C406 C2001 R402 C405 FB7101 C407 R410 R409 C2003 R7705 R7114 IC401 C7121 C401...
Page 56 LC-20B2UA LC-20B2UB P3704 R3756 R3701 FH3701 FH3702 FH3703 FH3704 C3700 D3703 R3718 FB3701 C3711 C3713 R3721 R3720 FB3709 R3717 C3703 R3768 R3706 IC3701 TU3201 R3703 R3707 C3706 R3708 R3705 C3705 R3711 C3707 R3709 R3760 C3719 R3727 R3732 C3725 C3716 L3704...
Page 57 LC-20B2UA LC-20B2UB P3602 P3601 P3500 P3502P3501 D3602 C3607 D3601 R3757 R3605 C3606 Q3602 C3603 C3605 R3604 R3608 R3607 C3602 C3604 C3601 Q3601 D3605 C3600 D3703 R3718 C3608 D3606 D3604 FB3701 C3609 C3711 C3713 D3607 R3721 R3720 R3722 FB3709 R3610 FB3700...
Page 58 LC-20B2UA LC-20B2UB FDC4 P6702 P6701 C6726 L6702 Q6706 Q6707 R6705 R6704 R6707 C6709 C6714 L6704 Q6708 R6711 FH6702 FH6703 FH6704 FH6705 P6705 INVERTER-A Unit (Chip Parts Side)
Page 59 LC-20B2UA LC-20B2UB FDC1 P6701 P6700 C6725 Q6702 L6700 C6704...
Page 60 LC-20B2UA LC-20B2UB T6709 C6721 T6708 C6720 T6707 Q6714 C6740 T6706 D6701 C6718 R6715 R6714 FH6707 FH6706 INVERTER-B Unit (Chip Parts Side)
Page 61 LC-20B2UA LC-20B2UB SW4008 P4005 SW4007 D4013 R4006 R4005 R4021 C4018 SW4002 SW4003 R4011 R4012 Q4003 SW4004 R4030 R4031 SW4006 D4008 D4009 D4010 RC/LED Unit (Chip Parts Side) P4004 CONTROL Unit (Chip Parts Side)
Page 62: Parts List
4. DESCRIPTION in USA: Contact your nearest SHARP Parts Distributor to order. in CANADA: Contact SHARP Electronics of Canada Limited For location of SHARP Parts Distributor, Please call Toll- Phone (416) 890-2100 Free; 1-800-BE-SHARP MARK: SPARE PARTS-DELIVERY SECTION MARQUE: SECTION LIVRAISON DES PIECES DE RECHANGE Ref.
Page 63 LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKA670FE12 C410 VCKYCY1EF104Z J 0.1 Ceramic C411 VCKYTV1AB105K Ceramic DIGITAL UNIT (Continued) C701 VCKYTV1CF105Z Ceramic C702 VCEAPF1CN226M J 22 Electrolytic Q2007 VSDTC144EE/-1 J DTC144EE C703 VCKYTV1CF105Z...
Page 64 LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKA670FE12 C7010 VCKYCY1EF104Z J 0.1 Ceramic C7012 VCKYCY1EF104Z J 0.1 Ceramic DIGITAL UNIT (Continued) C7013 VCKYCY1EF104Z J 0.1 Ceramic C7014 VCKYCY1EF104Z J 0.1 Ceramic C1134 VCKYCY1EF104Z J 0.1...
Page 65 LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKA670FE12 R1108 VRS-CY1JF103F J 10k 1/16W Metal Oxide R1109 VRS-CY1JF333J J 33k 1/16W Metal Oxide DIGITAL UNIT (Continued) R1110 VRS-CY1JF104J J 100k 1/16W Metal Oxide R1111 VRS-CY1JF683J...
Page 66 LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKA670FE12 R2068 VRS-CY1JF223J J 22k 1/16W Metal Oxide R7002 VRS-CY1JF471J J 470 1/16W Metal Oxide DIGITAL UNIT (Continued) R7003 VRS-CY1JF471J J 470 1/16W Metal Oxide R7004 VRS-CY1JF182J J 1.8k 1/16W Metal Oxide...
Page 67: Ë Analog Unit
LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKA670FE12 D3601 VHDiMN10///-1 J Diode D3602 VHDiMN10///-1 J Diode DIGITAL UNIT (Continued) D3603 VHDiMN10///-1 J Diode D3604 VHDiMN10///-1 J Diode FB7102 RBLN-0059CEZZ J Ferrite Bead D3605 VHDiMN10///-1...
Page 68 LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKB128DE03 C3711 VCKYCY1HB562K J 5600p 50V Ceramic C3712 VCAAPF1CJ826MY J 82 Electrolytic ANALOG UNIT (Continued) C3713 VCKYCY1HB562K J 5600p 50V Ceramic C3714 VCEASH1HN476MY J 47 Electrolytic C3334 VCKYCY1EF104Z J 0.1...
Page 69 LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKB128DE03 R3605 VRS-CB1JF824JY J 820k 1/16W Metal Oxide R3606 VRS-CA1JF824JY J 820k 1/16W Metal Oxide ANALOG UNIT (Continued) R3607 VRS-CB1JF562J J 5.6k 1/16W Metal Oxide R3608 VRS-CB1JF562J J 5.6k 1/16W Metal Oxide...
Page 70: Ë Control Unit
LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKB128DE03 DUNTKB132DE01 ANALOG UNIT (Continued) INVERTER-A UNIT TRANSISTORS J3701 QJAKE0193CEZZ J (DC POWER INPUT(DC 13V)) AK Q6700 VSFZT1053A/-1 J FZT1053A P3502 QPLGN0478GEZZ J Plug, 4-pin Q6701 VSFZT1053A/-1...
Page 71: Ë Inverter-B Unit
LC-20B2UA LC-20B2UB Ref. No. Part No. Description Code Ref. No. Part No. Description Code DUNTKB133DE01 INVERTER-B UNIT TRANSISTORS Q6709 VSFZT1053A/-1 J FZT1053A Q6710 VSFZT1053A/-1 J FZT1053A Q6711 VS2SA1530AR-1 J 2SA1530AR Q6712 VSFZT1053A/-1 J FZT1053A Q6713 VSFZT1053A/-1 J FZT1053A Q6714 VS2SA1530AR-1...
Page 72: Ë Cabinet And Mechanical Parts
LC-20B2UA LC-20B2UB CABINET AND MECHANICAL PARTS CONTROL UNIT INVERTER-A UNIT 1-12 DIGITAL UNIT 1-11 INVERTER-B UNIT 1-11 1-12 1-10 RC/LED UNIT ANALOG UNIT 5-10 5-20 5-19 5-12 5-11 5-16 5-17 3-11 5-18 5-21 5-15 3-17 5-14 5-19 5-20 5-13 3-18...
Page 73 — (LC-20B2UA) HiNDP5968CEZZ J Model Label(LC-20B2UA) GCOVA2103CEKB J Chassis Frame Cover HiNDPA078WJSA J Model Label(LC-20B2UB) (LC-20B2UB) TCAUH3096CESA J Caution Label(LC-20B2UA) AE GCOVA2106CEKA J Chassis Frame(LC-20B2UA) TCAUH3096CESB J Caution Label(LC-20B2UB) AE GCOVA2106CEKB J Chassis Frame(LC-20B2UB) JBTN-2066CEKA J Power Button CDAi-1122CE05 J Stand(LC-20B2UA)
Page 74: Ë Accessories Parts
Part No. Description Code Ref. No. Part No. Description Code PACKING PARTS SUPPLIED ACCESSORIES (NOT REPLACEMENT ITEM) LHLDW0109CESA J Cable Clamp, x2(LC-20B2UA) AD SPAKC5679CEZZ – Packing Case — LHLDW0109CESB J Cable Clamp, x2(LC-20B2UB) AD (LC-20B2UA) QACCD3097CEPA J AC Cord å SPAKCA110WJZZ –...
Page 75: Packing Of The Set
LC-20B2UA LC-20B2UB PACKING OF THE SET Operation Manual (TiNS-7604CEN1(LC-20B2UA)) (TiNS-A181WJZZ(LC-20B2UB)) Cable Clamp (2 pcs.) (LHLDW0119CESA(LC-20B2UA)) (LHLDW0119CESB(LC-20B2UB)) Dry Battery (2 pcs.) Wireless Remote Control AC Adapter (RRMCG1664CESA(LC-20B2UA)) (UADP-0243CEPZ) (RRMCG1664CESB(LC-20B2UB)) AC Cord (QACCD3097CESA) Antenna Cable (QCNWG0003CEPA) Buffer Material(Top and Bottom) (SPAKXA005WJZZ(LC-20B2UA)) (SPAKXA050WJZZ(LC-20B2UB))
Page 76 LC-20B2UA LC-20B2UB COPYRIGHT © 2002 BY SHARP CORPORATION ALL RIGHTS RESERVED. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher.

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Sharp LC-20B2UA Service Manual

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