Samsung LA15S51B Schematic

TFT-LCD TV

Chassis Model SP15SO LA15S51B

Manual

SERVICE

TFT-LCD TV CONTENTS

1. Precautions

2. Product Specifications

3. Disassembly & Reassembly

4. Alignment & Adjustments

5. Troubleshooting

6. Exploded View & Parts List

7. Electrical Parts List

8. Block Diagram

9. Wiring Diagram

10. PCB Layout

11. Schematic Diagrams

12. Panel Description

Samsung Electronics Co.,Ltd.

416, Maetan-3Dong, Yeongtong-Gu, Suwon City, Gyeonggi-Do, Korea, 443-742 Printed in Korea P/N : BN82-00131F-00 URL : http://itself.sec.samsung.co.kr/

- 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.

1 Precautions

1-1

1-1-1 Warnings

1. For continued safety, do not attempt to modify the circuit board.

2. Disconnect the AC power and DC Power Jack before servicing.

1-1-2 Servicing the LCD Monitor

1. When servicing the LCD TV Disconnect the AC line cord from the AC outlet.

2. It is essential that service technicians have an accurate voltage meter available at all times. Check the calibration of this meter periodically.

1-1-3 Fire and Shock Hazard

Before returning the LCD TV to the user, perform the following safety checks:

1. Inspect each lead dress to make certain that the leads are not pinched or that hardware is not lodged between the chassis and other metal parts in the LCD TV.

2. Inspect all protective devices such as nonmetallic control knobs, insulating materials, cabinet backs, adjustment and compartment covers or shields, isolation resistorcapacitor networks, mechanical insulators, etc.

3. Leakage Current Hot Check (Figure 1-1):

WARNING: Do not use an isolation

transformer during this test.

Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI C101.1, Leakage Current for Appliances), and Underwriters Laboratories (UL Publication UL1410,

59.7).

Figure 1-1. Leakage Current Test Circuit

4. With the unit completely reassembled, plug the AC line cord directly into a 120V AC outlet. With the unit’s AC switch first in the ON position and then OFF, measure the current between a known earth ground (metal water pipe, conduit, etc.) and all exposed metal parts, including: metal cabinets, screwheads and control shafts. The current measured should not exceed 0.5 milliamp. Reverse the power-plug prongs in the AC outlet and

repeat the test.

1-1-4 Product Safety Notices

Some electrical and mechanical parts have special safetyrelated characteristics which are often not evident from visual inspection. The protection they give may not be obtained by replacing them with components rated for higher voltage, wattage, etc. Parts that have special safety characteristics are identified by on schematics and parts lists. A substitute replacement that does not have the same safety characteristics as the recommended replacement part might create shock, fire and / or other hazards. Product safety is under review continuously and new instructions are issued whenever appropriate.

1 Precautions

Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock.

1-1 Safety Precautions

1-2-1 General Ser vicing

Precautions

1. Always unplug the unit’s AC power cord from the AC power source and disconnect the DC Power Jack before attempting to: (a) remove or reinstall any component or assembly, (b) disconnect PCB plugs or connectors, (c) connect a test component in parallel with an electrolytic capacitor.

2. Some components are raised above the printed circuit board for safety. An insulation tube or tape is sometimes used. The internal wiring is sometimes clamped to prevent contact with thermally hot components. Reinstall all such elements to their original position.

3. After servicing, always check that the screws, components and wiring have been correctly reinstalled. Make sure that the area around the serviced part has not been damaged.

1. Immediately before handling any semiconductor components or assemblies, drain the electrostatic charge from your body by touching a known earth ground. Alternatively, wear a discharging wrist-strap device. To avoid a shock hazard, be sure to remove the wrist strap before applying power to the monitor.

2. After removing an ESD-equipped assembly, place it on a conductive surface such as aluminum foil to prevent accumulation of an electrostatic charge.

3. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESDs.

4. Use only a grounded-tip soldering iron to solder or desolder ESDs.

5. Use only an anti-static solder removal device. Some solder removal devices not classified as “anti-static” can generate electrical charges sufficient to damage ESDs.

4. Check the insulation between the blades of the AC plug and accessible conductive parts (examples: metal panels, input terminals and earphone jacks).

5. Insulation Checking Procedure: Disconnect the power cord from the AC source and turn the power switch ON. Connect an insulation resistance meter (500 V) to the blades of the AC plug.

The insulation resistance between each blade of the AC plug and accessible conductive parts (see above) should be greater than 1 megohm.

6. Always connect a test instrument’s ground lead to the instrument chassis ground before connecting the positive lead; always remove the instrument’s ground lead last.

6. Do not remove a replacement ESD from its protective package until you are ready to install it. Most replacement ESDs are packaged with leads that are electrically shorted together by conductive foam, aluminum foil or other conductive materials.

7. Immediately before removing the protective material from the leads of a replacement ESD, touch the protective material to the chassis or circuit assembly into which the device will be installed.

Caution: Be sure no power is applied to

the chassis or circuit and observe all other safety precautions.

8. Minimize body motions when handling unpackaged replacement ESDs. Motions such as brushing clothes together, or lifting your foot from a carpeted floor can generate enough static electricity to damage an ESD.

1 Precautions

1-2

1-3 Electrostatically Sensitive Devices (ESD) Precautions

Some semiconductor (solid state) devices can be easily damaged by static electricity. Such components are commonly called Electrostatically Sensitive Devices (ESD). Examples of typical ESD are integrated circuits and some field-effect transistors. The following techniques will reduce the incidence of component damage caused by static electricity.

1-2 Ser vicing Precautions

WARNING: An electrolytic capacitor installed with the wrong polarity might explode. Caution: Before servicing units covered by this service manual, read and follow the Safety Precautions

section of this manual.

Note: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety

precautions, always follow the safety precautions.

2 Product Specifications

2-1

2 Product Specifications

2-1 Specifications

LCD Panel

TFT-LCD panel, RGB vertical stripe, normaly white, 15-Inch viewable, 0.297 mm pixel pitch

Scanning Frequency Horizontal : 30 kHz ~ 69 kHz (Automatic)

Vertical : 50 Hz ~ 75 Hz (Automatic) Display Colors 16.2 Million colors Maximum Resolution Horizontal : 1024 Pixels

Vertical : 768 Pixels Input Video Signal

Input Sync Signal Type : Seperate H/V

Level : TTL level Active Display

Horizontal/Vertical AC power voltage & Frequency

AC 100~240V, (50/60Hz) Power Consumption 40W (Maximum) (Power Saving : < 3W) Dimensions(W x D x H)

Set

14.2 x 2.5 x 13.3 Inches (360.2 x 64.2 x 338.6 mm)(State of stand disassembled)

14.2 x 7.6 x 15.6 Inches (360.2 x 192.9 x 396.5 mm)(State of stand installed)

Package 18.4 x 17.0 x 6.0 Inches (467 x 431 x 153 mm)

Weight

Set 3.6 Kg (7.9 Ibs)

Environmental Considerations

° ° ° °

TV System

Antena Input

–

Item

Description

304.1 mm / 228.1 mm

Tunning Frequency Synthesize

Sound MONO, STEREO, DUAL1,2, A2/NICAM

System PAL/SECAM/NTSC4.43, NTSC 3.58

2 Product Specifications

2-2

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15

2-2 Pin Assignments

RCA Green

RCA Blue

RCA Red

RCA White

RCA Red

GND

Pb (Cb)

GND

Pr (Cr)

GND

Audio L

GND

Audio R

GND

2-2-1 DVD

RCA White

RCA Red

CVBS

Audio L

GND

Audio R

GND

2-2-3 A/V

RCA Yellow

Separate

1 2 3 4 5

GND

C GND GND

2-2-2 S-Video

Separate

Red

Green

Blue

GND

GND (DDC Return)

GND-Red

GND-Green

GND-Blue

No Connection

GND-Sync / Self Test

GND

DDC Data

H - Sync V - Sync

DDC Clock

2-2-4 D-SUB

2 Product Specifications

2-3

Separate Sync

2-3 Timing Chart

- This section of the service manual describes the timing that the computer industry recognizes as standard for computer-generated video signals.

C D

Video

Sync

Video

Q R S

A : Line time total B : Horizontal sync width O : Frame time total P : Vertical sync width C : Back porch D : Active time Q : Back porch R : Active time E : Front porch S : Front porch

H/V Composite Sync

Sync-on-Green

1024/75Hz

1024 x 768

60.023

16.660

1.219

2.235

13.003

0.203

75.029

13.328

0.050

0.466

12.795

0.017

78.750

Positive Positive

Separate

31.469

31.777

3.813

1.589

26.058

0.318

70.087

14.268

0.064

0.858

13.155

0.191

28.322

Negative

Positive

Separate

µ µ µ µ µ

IBM

640/75 Hz,

60Hz, 72Hz

640 x 480

800/75 Hz,

56Hz,

60Hz, 72Hz

800 x 600

1024/60Hz

1024 x 768

VGA2/

70 Hz

720 x 400

VGA3/

60 Hz

640 x 480

Table 2-1 Timing Chart

31.469

31.778

3.813

1.589

26.058

0.318

59.940

16.683

0.064

0.794

15.761

0.064

25.175

Negative Negative

Separate

37.500

26.667

2.032

3.810

20.317

0.508

75.000

13.333

0.080

0.427

12.800

0.027

31.500

Negative Negative Separate

46.875

21.333

1.616

3.232

16.162

0.323

75.000

13.333

0.064

0.448

12.800

0.021

49.500

Positive Positive

Separate

48.363

20.677

2.092

2.462

15.754

0.369

60.004

16.666

0.124

0.600

15.880

0.062

75.000

Negative Negative Separate

Mode

VESA

Timing

Memo

2 Product Specifications

2-4

3 Disassembly and Reassembly

3-1

3 Disassembly and Reassembly

This section of the service manual describes the disassembly and reassembly procedures for the LA15S51B TFT-LCD TV.

WARNING: This monitor contains electrostatically sensitive devices. Use caution

when handling these components.

3-1 Disassembly

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

2. Follow these directions carefully; never use any metal instrument except provided jig to separate the cabinet.

3. R/Cover opening jig : BH81-00001A

1. Place monitor face down on cushioned table. Remove 6 screws from the rear cover and lift up the rear cover.

2. Disconnect Lamp wire, LVDS cable and Speaker cable.

3 Disassembly and Reassembly

3-2

3. Remove 11 screws from the boards and lift up the boards.

4. Remove 6 screws from the shield PCB.

5. Lift up the shield PCB and lift up the LCD panel.

3 Disassembly and Reassembly

3-3

1. After confirm there is nothing on the desk, turn the LCD module over and put it on a flat desk set to the ground.

2. Remove 2 screws for the lamp unit.

3-2 Replacement Order of Lamp Assemblies

3 Disassembly and Reassembly

3-4

3-3 Reassembly

Reassembly procedures are in the reverse order of disassembly procedures.

4. Please fix the new lamp units on the LCD module : opposite process 2 and 3.

3. Slide the lamp unit out. Please take out the lamp unit from the LCD module.

Slide the lamp unit out.

4 Alignments and Adjustments

4-1

4 Alignments and Adjustments

4-1 General Alignment Instuction

1. Usually, a color LCD TV 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 DC 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.

4 Alignments and Adjustments

4-2

4-2 Factory Mode Adjustments

4-2-1 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

4-2-2 Factory Mode Tree

4 Alignments and Adjustments

4-3

4 Alignments and Adjustments

4-4

7. Test Pattern (Test Patter n of VCTi)

1) VCTi

2) Toshiba

3) Gray Bar

4) Gray

5) Green

6) Color Bar

7) Cross

8. Bus Stop

- Bus stop is used data communication.

9. Chcek Sum

- Display the current check sum size of the MICOM.

10. Reset

- Initializes the data in the MICOM.

11. T-VNC15PEA-1009 2004/08/31

- Display the MICOM program version.

4-2-3 White Balance

- COMPONENT & PC MODE NO ADJUST W/B

± ±

4 Alignments and Adjustments

4-5

4-2-4 Calibration

+ 37 hidden pages