Samsung LE20S81BX Schematic

TFT-LCD TV

Chassis GJA20SEU

Model LE20S81BX

Manual

SERVICE

TFT-LCD TV Fashion Feature

- Luxurious Slim Design

- Supreme Picture Quality

- Supreme Sound Quality

- Supreme Convenience Quality

- Convenience for Users

ii

Copyright

ⓒ 2007 by Samsung Electronics Co., Ltd.
All rights reserved.
This manual may not, in whole or in part, be copied,

photocopied, reproduced, translated, or converted to any
electronic or machine readable form without prior
written permission of Samsung Electronics Co., Ltd.

LE26S81BX/LE32S81BX/LE37S81BX/LE40S81BX /
LE46S81BX Service Manual

First edition June 2007.
Printed in Korea.

Trademarks

Samsung is the registered trademark of Samsung
Electronics Co., Ltd.
LE26S81BX/LE32S81BX/LE37S81BX/LE40S81BX /
LE46S81BX and Macmaster Cable Adapter are
trademarks of Samsung Electronics Co., Ltd.

Macintosh and Power Macintosh are trademarks of
Apple Computer, Inc.

All other trademarks are the property of their respective
owners.

Contents

11. Precautions

………………………………………………………………………………………………………………………………………

11-1

1-1 Safety Precautions ……………………………………………………………………………………………………………………… 1-1

1-2 Servicing Precautions …………………………………………………………………………………………………………………… 1-2

1-3 Static Electricity Precautions …………………………………………………………………………………………………………… 1-2

1-4 Installation Precautions…………………………………………………………………………………………………………………… 1-3

2

2. Product specifications

…………………………………………………………………………………………………………………………

22-1

2-1 Fashion Feature…………………………………………………………………………………………………………………………… 2-1

2-2 LE26S81BX Specifications ……………………………………………………………………………………………………………… 2-2

2-3 LE32S81BX Specifications ……………………………………………………………………………………………………………… 2-3

2-4 LE37S81BX Specifications ……………………………………………………………………………………………………………… 2-4

2-5 LE40S81BX Specifications ……………………………………………………………………………………………………………… 2-5

2-6 LE46S81BX Specifications ……………………………………………………………………………………………………………… 2-6

2-7 Spec Comparison ………………………………………………………………………………………………………………………… 2-6

2-8 Option Specification ……………………………………………………………………………………………………………………… 2-7

3

3. Alignments and Adjustments

…………………………………………………………………………………………………………………

33-1

3-1 Service Instruction ……………………………………………………………………………………………………………………… 3-1

3-2 How to Access Service Mode …………………………………………………………………………………………………………… 3-2

3-3 Factory Data ……………………………………………………………………………………………………………………………… 3-3

3-4 Service Adjustment ……………………………………………………………………………………………………………………… 3-12

3-5 Software Upgrade ……………………………………………………………………………………………………………………… 3-15

4

4. Troubleshooting

………………………………………………………………………………………………………………………………

44-1

4-1 First Checklist for Troubleshooting ………………………………………………………………………………………………………4-1

4-2 Checkpoints by Error Mode ……………………………………………………………………………………………………………… 4-2

5

5. Exploded View and Parts List

…………………………………………………………………………………………………………………

55-1

5-1 LE26S81BX Exploded View……………………………………………………………………………………………………………… 5-1

5-2 LE26S81BX Parts list …………………………………………………………………………………………………………………… 5-2

5-3 LE32S81BX Exploded View……………………………………………………………………………………………………………… 5-3

5-4 LE32S81BX Parts list …………………………………………………………………………………………………………………… 5-4

5-5 LE37S81BX Exploded View……………………………………………………………………………………………………………… 5-5

5-6 LE37S81BX Parts list …………………………………………………………………………………………………………………… 5-6

5-7 LE40S81BX Exploded View……………………………………………………………………………………………………………… 5-7

5-8 LE40S81BX Parts list …………………………………………………………………………………………………………………… 5-8

6

6. Electrical Parts List

……………………………………………………………………………………………………………………………

66-1

6-1 LE26S81BX Parts List …………………………………………………………………………………………………………………… 6-1

6-2 LE32S81BX Parts List ………………………………………………………………………………………………………………… 6-22

6-3 LE37S81BX Parts List ………………………………………………………………………………………………………………… 6-38

6-4 LE40S81BX Parts List ………………………………………………………………………………………………………………… 6-55

7

7. Block Diagram

…………………………………………………………………………………………………………………………………

77-1

Contents

88. Wiring Diagram

…………………………………………………………………………………………………………………………………

88-1

8-1 LE26S81BX / LE32S81BX / LE37S81BX / LE40S81BX / LE46S81BX Wiring Diagram …………………………………………8-1

8-2 Main Board Layout ……………………………………………………………………………………………………………………… 8-2

8-3 PIN characteristic ………………………………………………………………………………………………………………………… 8-3

8-4 Power Board Layout ……………………………………………………………………………………………………………………… 8-6

99. Schematic Diagrams

……………………………………………………………………………………………………………………………

99-1

10. O

Operating Instructions and Installation

………………………………………………………………………………………………………

110-1

10-1 Front …………………………………………………………………………………………………………………………………… 10-1

10-2 Connection Panel ……………………………………………………………………………………………………………………… 10-2

10-3 Remote control ………………………………………………………………………………………………………………………… 10-4

10-4 Installing the Stand …………………………………………………………………………………………………………………… 10-5

10-5 Installing the Wall Mount Kit ………………………………………………………………………………………………………… 10-5

1

11. Disassembly and Reassembly

………………………………………………………………………………………………………………

111-1

11-1 Disassembly …………………………………………………………………………………………………………………………… 11-1

11-2 Reassembly …………………………………………………………………………………………………………………………… 11-5

1

12. PCB Diagram

…………………………………………………………………………………………………………………………………

112-1

13. CCircuit Descriptions

……………………………………………………………………………………………………………………………

113-1

13-1 Block description ……………………………………………………………………………………………………………………… 13-1

13-2 Main Block ……………………………………………………………………………………………………………………………… 13-3

13-3 SMPS Board …………………………………………………………………………………………………………………………… 13-4

1

14. Reference Infomation

………………………………………………………………………………………………………………………

114-1

14-1 Technical Terms ……………………………………………………………………………………………………………………… 14-1

14-2 Pin Assignments ……………………………………………………………………………………………………………………… 14-4

14-3 Timing Chart …………………………………………………………………………………………………………………………… 14-7

14-4 Panel Description …………………………………………………………………………………………………………………… 14-11

©2007 Samsung Electronics Co.,Ltd.
All rights reserved.

Printed in Korea
P/N : BN82-00245A-00

This Service Manual is a property of Samsung
Electronics Co.,Ltd.

Any unauthorized use of Manual can be punished under
applicable International and/or domestic law.

Area

GSPN(Global Service Partner Network)

North America
Latin America
CIS
Europe
China
Asia
Mideast & Africa

http://service.samsungportal.com
http://latin.samsungportal.com
http://cis.samsungportal.com
http://europe.samsungportal.com
http://china.samsungportal.com
http://asia.samsungportal.com
http://mea.samsungportal.com

Web Site

3 Alignments and Adjustments

3-1

3 Alignments and Adjustments

3-1 Ser vice Instr uction

1. Usually, a color TV-VCR needs only slight touch-up adjustment upon installation.
Check the basic characteristics such as height, horizontal and vertical sync.

2. Use the specified test equipment or its equivalent.

3. Correct impedance matching is essential.

4. Avoid overload. Excessive signal from a sweep generator might overload the front-end
of the TV. When inserting signal markers, do not allow the marker generator to distort
test result.

5. Connect the TV only to an AC power source with voltage and frequency as specified on
the backcover nameplate.

6. Do not attempt to connect or disconnect any wire while the TV is turned on. Make sure
that the power cord is disconnected before replacing any parts.

7. To protect aganist shock hazard, use an isolation transform.

3 Alignments and Adjustments

3-2

3-2 How to Access Service Mode

3-2-1 Entering Factory Mode

1. To enter “Service Mode” Press the remote -control keys in this sequence :

- If you do not have Factory remote - control

- If you have Factory remote - control

3-3 Factory Data

▶
▶
▶
▶
▶
▶
▶
▶
▶
▶
▶

▶
▶
▶
▶
▶
▶

▶
▶
▶
▶
▶
▶
▶
▶
▶
▶
▶

-. OSD which the basic adjustment is added.
PC Auto Color
Video Auto Color
Reset
DLC/MWE Part
SFR PART
Sub Adjust
Adjust
Option
Checksum
Panel Information
Bus Stop : OFF
*. 2005/06/23: MCU firmware date.
*.

T-PLUS25NUS-0906: MCU firmware version information

(this information must be appended due to a compatibility problem report.)

1) Reset: Factory reset

2) Bus Stop: The communication Line ON / OFF
Move to the ( - ) / (+) key, select the 'Enter' key.

3) Auto adjustment

4) PC Auto Color/ Video Auto Color :in case that color
of all screen is wrong, excute the PC Auto color at
16 gray pattern(refer to attach left 16gray pattern)

5) Checksum: MCU firmware checksum information
(this information must be appended due to a compatibility problem report.)

POWER OFF POWER ONMUTE 1 8 2

POWER ON

Service
PC Auto Color

Video Auto Color
Reset
DLC/MWE Part
SFR PART
Sub Adjust
Adjust
Option
Checksum
Panel Information
Bus Stop : OFF

2006/01/02

-l

T-PLS23PEU-1002

INFO

FACTORY

Service
PC Auto Color

Video Auto Color

Service Function
Reset
Adjust

DLC/MWE Part
PC Auto Color

SFR PART
Option

Sub Adjust
Checksum

Adjust
Panel Information

Option
Reset

Checksum
Bus Stop

Panel Information
Bus Stop : OFF

2005/04/20
TM-BRHMS20WW-0714

2006/01/02
T-PLS23PEU-1002

3 Alignments and Adjustments

3-3

▶

6) Dynamic Luma Adjustment

" - " : RF, AV, S_Video -> all store
" + " : RF, AV, S_Video -> apart store

7) Special Function Register

DLC/MWE Part

NVRAM Reset
DLC- 0-10 0
MWE- 0-1 1
Demo 0-1 0
Brightness+ 0-255 100
Contrast+ 0-255 113
Sharpness+ -10-10 1
Hue+ 0-100 50
Saturation+ 0-255 125
R Offset 46
G Offset 50
B Offset 56
R Gain 58
G Gain 50
B Gain 51

SFR Part

DCXO Sel. 0
DCXO Tune 64
OVMADAPT 0-1 1
OVMTHR 0-3 2
IF Demod 0-63 38
F FI 0-1 0

R0:77 R1:71 R2:81
R3:18 R4:0 R5:1F

Sub Adjust
R Blk Lvl+ 0-63 28

G Blk Lvl+ 0-63 20
Peak Frq/DLY+0-3 0
Peak+ 0-63 40
Soft Clp Lvl- 0-3 0
W Limit- 0-15 8
R White Pnt+ 0-63 37
G White Pnt+ 0-63 31
B White Pnt+ 0-63 31
AGC T-O- 0-63 23

3 Alignments and Adjustments

3-4

8) UOC Adjustment

BKS : Black stretch
Wsx : White stretch

9) Option: Spread Step / Spread Span (for EMI test )

10) Panel Information

various function are included in information.

- Monitor On Time : Power On Time

- Panel Cycle : Panel On/off time (Power off, Mode
change, DPMS on/off ...)

- Panel : Panel on Time
(when the panel is changed , select the Reset )

- Lower lamp : Lower lamp on time

(when the Lower lamp is changed , select the Reset )

- Upper lamp : Upper Lamp on time
(when the Upper Lamp is changed , select the Reset)

UOC Adjust
BKS- 0-1 1

WSx- 0-3 2

0 0 0 0 0 20 20 2
0 20 20 20 20 20 20 20 2
0 20 20 20 19 26 …..

3 Alignments and Adjustments

3-5

3-4-1 EDID input method

3-4 Ser vice Adjustment

3-4-2 EDID input method (Windows Progr am)

-SAMSUNG LCD TV support the DDC control JIG.

-You can see the connection between PC and LCD TV.

1. Execute "WinDDC.EXE"

2. Click "Open[F5]"

3 Alignments and Adjustments

3-6

3. Select Connected Port#1 and Click Next OK.

4. Select Connected Port#1 and Click Next OK.
Find file name : VC20

5. Click Next (OK) button.

6.

Select enter button (on Key-Board) After Monitor S/N input

.

3 Alignments and Adjustments

3-7

8. Check "DDC OK".

3-4-3 Micom ( TDA15001H) Program Upgrade

1. Program Upgrade Jig

2. Connect the parallel Port

3 Alignments and Adjustments

3-8

3. Connect Jig to CN905 on PCB Ass'y

4. Click " WISP " Icon on Computer

5. Check "Automatic mode on".

6. Click "Browser" button : Select the

Code , Click "Auto Execute" button
Check Erase and Write OK In "General"
window and check Verify OK in "ISP status"
window.

7 Block Diagrams

7-1

7 Block Diagram

Memo

7 Block Diagrams

7-2

13 Circuit Descriptions

13-1

13 Circuit Descriptions

13-1 Overall Block Structure

13 Circuit Descriptions

13-2

13-2-1 MAIN BOARD POWER TREE

13-2 Partial Block Description

13 Circuit Descriptions

13-3

13-2-2 WIRING DIAGRAM

CN100(9P) : To IP Board
CN402(50P) : To 20" Panel
CN905(5P) : To Program Download Jig
CN906(20P) : To Scart
CN600(3P) : Speaker
CN907(12P) : To Function Board

CN100

CN402 CN906CN905

CN907CN600

13 Circuit Descriptions

13-4

11 Disassembly and Reassembly

11-1

11 Disassembly and Reassembly

This section of the service manual describes the disassembly and reassembly procedures for the TFT-LCD
TV.

WARNING : This monitor contains electrostatically sensitive devices. Use caution when

handling these components.

11-1 Disassembly

Cautions : 1. Disconnect the monitor from the power source before disassembly.

2. Follow these directions carefully; never use metal instruments to pry apart the
cabinet.

Description Picture Description

1. Place monitor face down on cushioned table.
Remove screws from the rear cover.
Remove screws from the stand.

11 Disassembly and Reassembly

11-2

3. Remove Screws from the stand BRKT and lift
up the stand BRKT.

Description Picture Description

2. Lift up the rear cover and remove the stand.

11 Disassembly and Reassembly

11-3

5. Remove screws from the boards and lift up the
boards.

Description Picture Description

4. Disonnect cable from the boards.

11 Disassembly and Reassembly

11-4

7. Lift up the BRKT.

Description Description Picture

6. Remove screws.

11 Disassembly and Reassembly

11-5

Description Description Picture

11-2 Reassembly

Reassembly procedures are in the reverse order of disassembly procedures.

11 Disassembly and Reassembly

11-6

Memo

6 Electrical Parts List

6-1

Level Loc. No. Code No. Description & Specification Q'ty SA/SNA

LE22S81BX/XEH LE22S81B,N40B/22S80-GJA,22,LCD-TV,HUNGAR

0.1 M0001 BN90-01372B ASSY COVER FRONT;LE22S81BX/XEC 1 S.N.A
..2 T0003 BN96-05965B ASSY COVER P-FRONT;22S81,EO,,ABS+PMMA,HB 1 S.A
...3 M0081 6003-001024 SCREW-TAPTITE;RWH,+,-,B,M4,L12,ZPC(WHT), 4 S.A
...3 M0081 6003-001188 SCREW-TAPTITE;BH,+,-,B,M4,L10,ZPC(WHT),S 2 S.N.A
...3 M0081 6003-001188 SCREW-TAPTITE;BH,+,-,B,M4,L10,ZPC(WHT),S 2 S.N.A
...3 T0060 BN61-01655A SPRING ETC;STS-304 SUS,D8,L12,T0.5 1 S.N.A
...3 CCM1 BN63-02183D COVER-SHEET;Rhcm,PE Vinyl,T0.05,680mm,20 0.6 S.N.A
...3 M0112 BN63-03796B COVER-FRONT;22S81,EO,ABS+PMMA,HB,BK23,S/ 1 S.N.A
...3 T0023 BN64-00589A KNOB POWER;32S81,PC,-,-,-,-,VIOLET,-,- 1 S.N.A
...3 M0145 BN96-03466A ASSY BOARD P-FUNCTION;SONOMA,SJ06-01-008 1 S.A
...3 M0025 BN96-04634A ASSY DECORATION P;22S86,-,ABS HB,IV16,BK 1 S.N.A

....4 BN61-03261C BOSS-TAPE;Tulip,ACRYL,T1.1,W24mm,GRAY,TA 0.5 S.N.A

....4 BN64-00709A DECORATION-BOTTOM;JASMINE22,ABS HB,IV16, 1 S.N.A

...3 M0146 BN96-04884G ASSY BOARD P-POWER & IR;LE22S86BDX,CT500 1 S.A
...3 T0175 BN96-06066A ASSY SPEAKER P;16ohm,4pin,3W,350/750 1 S.A
...3 T0054 BN64-00590A KNOB-DECORATION;JASMINE 32,ABS,-,-,-,HB, 1 S.N.A
...3 T0059 BN64-00366A INDICATOR LED;ROME-I,PC,CLEAR,ALL MODEL 1 S.N.A
...3 T0022 BN64-00467E KNOB CONTROL;37S62,SONOMA26,32,40,ABS,HB 1 S.N.A

0.1 M0002 BN90-01373B ASSY COVER REAR;LE22S81BX/XEC 1 S.N.A
..2 T0081 6002-001294 SCREW-TAPPING;BH,+,,M4,L16,ZPC(BLK) 9 S.A
..2 M0013 BN96-05966B ASSY COVER P-REAR;22S81,EO,,HIPS,HB,,BK5 1 S.A
...3 M0081 6003-001188 SCREW-TAPTITE;BH,+,-,B,M4,L10,ZPC(WHT),S 4 S.N.A
...3 T0101 BN61-03346A BRACKET-WALL;LCD TV,SECC,T1.2 4 S.N.A
...3 M0006 BN63-03806B COVER-REAR;22S81,EO,HIPS,HB,BK500,Ready 1 S.N.A
...3 T0071 BN64-00671C INLAY-TERMINAL;19R81,EO,PS SHEET,T0.5,Re 1 S.N.A
...3 T0064 BN65-00002A CLAMPER CORE;BORDEAUX,LDPE,-,-,BLK,- 1 S.N.A

0.1 M0216 BN90-01375A ASSY STAND;LE22S86BDX/XEC 1 S.N.A
..2 M0027 BN96-04745A ASSY STAND P-BASE;-,22,23,26S81,-,ABS+PM 1 S.A
...3 T0081 6002-001294 SCREW-TAPPING;BH,+,,M4,L16,ZPC(BLK) 4 S.A
...3 M0081 6003-001239 SCREW-TAPTITE;FH,+,-,B,M4,L10,ZPC(WHT),S 4 S.A
...3 T0920 BN61-03024A GUIDE-STAND;JASMINE 26,ABS,-,-,-,BK500,V 1 S.N.A
...3 BN61-03028A BRACKET-STAND BOTTOM;JASMINE 26",SECC,T1 1 S.N.A
...3 CCM1 BN63-02183D COVER-SHEET;Rhcm,PE Vinyl,T0.05,680mm,20 0.2 S.N.A
...3 T0004 BN63-03178A COVER-STAND BASE;JASMINE 26",ABS+PMMA,HB 1 S.N.A
...3 T0132 BN73-00052A RUBBER FOOT;ARES 17,CR Rubber Gray,T1.5 4 S.N.A
..2 T0524 6902-000561 BAG PE;HDPE+NITRON(DOUBLE),T0.015+T0.5,W 1 S.N.A

0.1 M0106 BN91-01035Z ASSY LCD-STZ;LS22DPWCSQ/EDC 1 S.N.A
..2 M0215 BN07-00346A LCD-PANEL;LTM220M1-L01,Doppler,8BIT,493. 1 S.A

0.1 M0017 BN91-01757A ASSY CHASSIS;LE22S81BX/* 1 S.N.A
..2 M0014 BN94-01464A ASSY PCB MAIN-AMLCD;LE22S81BX/* 1 S.A
...3 JA3002 3701-001400 CONNECTOR-DSUB;15P,3R,FEMALE,STRAIGHT,Ni 1 S.A
...3 CN330 3711-000058 HEADER-BOARD TO CABLE;BOX,4P,1R,2.5MM,AN 1 S.A
...3 CN330 3711-003846 HEADER-BOARD TO CABLE;BOX,8P,1R,2mm,ANGL 1 S.A
...3 CN330 3711-004712 HEADER-BOARD TO CABLE;BOX,9P,1R,2mm,STRA 1 S.A
...3 CN330 3711-005606 HEADER-BOARD TO CABLE;BOX,30P,2R,2mm,STR 1 S.A
...3 JA4001 3722-000498 JACK-SCART;21P,-,SN,BLK,NO 1 S.A
...3 JA330 3722-001061 JACK-PHONE;1P,3.6PI,AG,BLK,N 1 S.A
...3 JA330 3722-001061 JACK-PHONE;1P,3.6PI,AG,BLK,N 1 S.A
...3 JA332 3722-001734 JACK-VHS;4P,SN,BLK,STRAIGHT 1 S.A
...3 JA333 3722-002360 JACK-PIN;3P,AU,GRN/BLU/RED,STRAIGHT 1 S.A

6 Electrical Parts List

You can search for updated part codes through ITSELF web site.

URL : http://itself.sec.samsung.co.kr/

6-1 LE22S81BX Parts List