Samsung LE26A41B, LE32A41B Service manual

TFT-LCD TV/MONITOR

Chassis Model DU26EO LE26A41B DU32EO LE32A41B

Manual

SERVICE

TFT-LCD TV/MONITOR CONTENTS

1. Precautions

2. Product Specifications

3. Disassembly & Reassembly

4. Alignment & Adjustments

5. Troubleshooting

6. Exploded View & Parts List

7. Parts List

8. Block Diagram

9. Wiring Diagram

10. PCB Layout

11. Schematic Diagrams

12. Panel Description

1 Precautions

LE26A41B/LE32A41B 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 Ser vicing the LCD Monitor

1. When servicing the LCD Monitor 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 monitor 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 monitor.

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

DEVICE UNDER TEST

TEST ALL

EXPOSED METAL

SURFACES

(READING SHOULD

NOT BE ABOVE 0.5mA)

LEAKAGE CURRENT

TESTER

2-WIRE CORD

ALSO TEST WITH

PLUG REVERSED (USING AC ADAPTER PLUG AS REQUIRED)

EARTH

GROUND

1 Precautions

1-2 LE26A41B/LE32A41B

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.

1-3 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

LE26A41B/LE32A41B 2-1

2 Product Specifications

2-1 LE26A41B, LE32A41B Specifications

LCD Panel

TFT-LCD panel, RGB vertical stripe, normaly white, 26-Inch viewable, 0.4425 (H) x 0.264(V)mm pixel pitch

TFT-LCD panel, RGB vertical stripe, normaly white, 32-Inch viewable, 0.537(H) x 0.537(V) mm pixel pitch

Scanning Frequency Horizontal : 30 kHz ~ 68 kHz (Automatic) Horizontal : 30 kHz ~ 61 kHz (Automatic)

Vertical : 50 Hz ~ 85 Hz (Automatic) Vertical : 56 Hz ~ 75 Hz (Automatic)

Display Colors 16.2 Million colors Maximum Resolution Horizontal : 1280 Pixels Horizontal :1366 Pixels

Vertical : 768 Pixels Vertical : 768 Pixels Input Video Signal Analog 0.7 Vp-p ± 5% positive at 75 Ω, internally terminated Input Sync Signal Type : Seperate H/V

Level : TTL level Maximum Pixel Clock rate

80 MHz 80 MHz

Active Display Horizontal/Vertical

AC power voltage & Frequency

AC 100 ~ 240V, 50 ~ 60 Hz Power Consumption 130 W 130 W Dimensions(W x D x H)

Set

32.6 x 10.9 x 20.5 Inches (827.0 X 278 X 520mm) After installation Stand 38.2 x 12.5 x 22.7 Inches (972.0 X317.0 X 577.5 mm) After installation Stand

37.0 x 13.3 x 27.4 Inches (827.5 X 112.5 X504.5 mm) Without stand 38.2 x 4.6 x 22.2 Inches (972.0 X 116.0 X 565.0 mm) Without Stand

Package

37.0 x 13.3 x 27.4 Inches (965 X 338 X 695 mm) 44.5 x 16.0 x 22.9 Inches (1130 X 408 X 760 mm)

Weight

Set

(After installation Stand)

/ Package 18 Kg (39.7 Ibs) / 24 Kg (52.9 lbs) 21.5 Kg (54.0Ibs) / 28 Kg (61.7 lbs)

Environmental Considerations

Operating Temperature : 50 °F ~ 104 °F (10 °C ~ 40 °C)

Operating Humidity : 10 % ~ 80 %

Storage Temperature : -4 °F ~ 113 °F (-20 °C ~ 45 °C)

Storage Humidity : 5 % ~ 95 %

TV System

Antena Input 75Ω

– MAX Internal speaker Out : LN-P267W : Right => 5W, Left => 5W

LN-P327W : Right => 10W Left => 10W

Sound Characteristic

– BASS Control Range : -8 dB ~ + 8dB – TREBLE Control Range : -8 dB ~ +8 dB – Headphone Out : 10 mW MAX – Output Frequency : RF : 80 Hz ~ 15 kHz

A/V : 80 Hz ~ 20 kHz

System NTSC-M

Item

Description

LE26A41B

LE32A41B

556.4 mm / 339.8 mm 697.7 mm / 392.4 mm

Tunning Frequency Synthesize

Sound MONO, STEREO, SAP

2 Product Specifications

2-2 LE26A41B/LE32A41B

2-2 Pin Assignments

2-2-1 DVI-D (Digital)

Ref) DVI-D : Digital only

Pin No.

Signal Assignment

Pin No.

Signal Assignment

No.

Signal Assignment

1 2 3 4 5 6 7 8 9

RX2RX2+ GND NC NC DDC Clock (SCL) DDC Data (SDA) Analog Vertical Sync. RX1RX1+

11 12 13 14 15 16 17 18 19 20

GND NC NC DDC Input Power(+5V) IDENT_PC

5V RX0RX0+ GND NC

21 22 23 24

NC GND RXC+ RXC-

1234567 8

9 10111213141516

17 18 19 20 21 22 23 24

2 Product Specifications

LE26A41B/LE32A41B 2-3

Separate

1 2 3 4 5

GND

C GND GND

RCA Green

RCA Blue

RCA Red

RCA White

RCA Red

GND

Pb (Cb)

GND

Pr (Cr)

GND

Audio L

GND

Audio R

GND

2-2-3 S-Video

2-2-2 Component 1, 2

RCA White

RCA Red

CVBS

Audio L

GND

Audio R

GND

2-2-4 A/V

RCA Yellow

2 Product Specifications

2-4 LE26A41B/LE32A41B

2-3 Timing Char t

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

LN-P267W LN-P327W

47.712kHz

20.959

15.906

5.053

0.000

15.906

0.749

1.702

2.994 Positive

60.015Hz

16.662

16.097

0.566

0.000

16.097

0.063

0.105

0.377

85.500MHz

2-3-1 LCD Panel Mode1 mode

2 Product Specifications

LE26A41B/LE32A41B 2-5

2-3-1 Supported Modes (1)

2 Product Specifications

2-6 LE26A41B/LE32A41B

2-3-1 Supported Modes (2)

2 Product Specifications

LE26A41B/LE32A41B 2-7

2-3-1 Supported Modes (3)

(Only LN-P327W)

1360/60Hz 1360x768

47.712kHz

20.959

15.906

5.053

0.000

15.906

0.749

1.702

2.994 Positive

60.015Hz

16.662

16.097

0.566

0.000

16.097

0.063

0.105

0.377

85.500MHz

2 Product Specifications

2-8 LE26A41B/LE32A41B

Memo

3 Disassembly and Reassembly

LE26A41B/LE32A41B 3-1

3 Disassembly and Reassembly

This section of the service manual describes the disassembly and reassembly procedures for the LE26A41B/LE32A41B LCD TV.

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

handling these components.

3-1 LE26A41B Disassembly

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

2. Remove the stand and lift up the rear cover.

3. Disconnect speaker cable, function cable from the shield and remove 18 screws from the shield and lift up the shield.

4. Disconnect CN811 connecter, LVDS cable, inverter cable from the boards.

1. Place LCD TV face down on cushioned table.

Remove 9 screws from the rear cover. Remove 4 screws from grip on the stand. and remove the stand.

3 Disassembly and Reassembly

3-2 LE26A41B/LE32A41B

5. Remove 6 screws from the Main board and lift up the board.

6. Remove 6 screws from the Sub power board and lift up the board.

7. Disconnect inverter cable. Remove 6 screws from the main power board and lift up the board.

8. Remove 8 screws

9. Remove 6 screws from the panel BRKT. Remove 16 screws from the cabinet BRKT and lift up the panel.

3 Disassembly and Reassembly

LE26A41B/LE32A41B 3-3

3-2 LE32A41B Disassembly

8. Lift up the panel. Remove 4 screws from the panel BRKT. (Lelt/Right) Disconnect BRKT from the panel.

2. Remove the stand and lift up the rear cover.

3. Disconnect speaker cable, function cable from the

shield and remove 18 screws from the shield and lift up the shield.

4. Disconnect CN811 connecter, LVDS cable, inverter

cable from the boards.

1. Place LCD TV face down on cushioned table. Remove 9 screws from the rear cover. Remove 4 screws from grip on the stand. and remove the stand.

3 Disassembly and Reassembly

3-4 LE26A41B/LE32A41B

5. Remove 6 screws from the Main board and lift up the board.

6. Remove 6 screws from the Sub power board and lift up the board.

7. Disconnect inverter cable. Remove 6 screws from the main power board and lift up the board.

8. Remove 13 screws

9. Remove 6 screws from the panel BRKT. Remove 14 screws from the cabinet BRKT and lift up the panel.

3 Disassembly and Reassembly

LE26A41B/LE32A41B 3-5

3-3 Reassembly

Reassembly procedures are in the reverse order of dissasembly procedures.

8. Lift up the panel. Remove 4 screws from the panel BRKT. (Lelt/Right) Disconnect BRKT from the panel.

Memo

3 Disassembly and Reassembly

3-6 LE26A41B/LE32A41B

4 Alignments and Adjustments

LE26A41B/LE32A41B 4-1

4 Alignments and Adjustments

4-1 General Alignment Instuction

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.

4 Alignments and Adjustments

4-2 LE26A41B/LE32A41B

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

- The buttons are active in the service mode.

1. Remote - Control Key : Power, Arrow Up, Arrow Down, Arrow Left Arrow Right, Menu, Enter, Number Key(0~9)

2. Function - Control Key : Power, CH +, CH -, VOL +, VOL -, Menu, TV/VIDEO(Enter)

INFO

MENU MUTE

T-DUO26OPEU-0033 07/22/2004 10:17:54 T-DUO32OPEU-0022 07/22/2004 10:17:54

4 Alignments and Adjustments

LE26A41B/LE32A41B 4-3

T-DUO26OPEU-0033 07/22/2004 10:17:54 T-DUO32OPEU-0022 07/22/2004 10:17:54

4 Alignments and Adjustments

4-4 LE26A41B/LE32A41B

T-DUO26OPEU-0033 07/22/2004 10:17:54 T-DUO32OPEU-0022 07/22/2004 10:17:54

4 Alignments and Adjustments

LE26A41B/LE32A41B 4-5

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