Samsung 800TFT Service Manual

COLOR MONITOR

SyncMaster 800TFT

Manual

SERVICE

COLOR MONITOR CONTENTS

1. Precautions

2. Product Specifications

3. Disassembly & Reassembly

4. Alignments & Adjustments

5. Troubleshooting

6. Exploded View & Parts List

7. Electrical Parts List

8. Block Diagram

9. Wiring Diagram

10. Schematic Diagrams

Samsung Electronics Co., Ltd. September 1999 Printed in Korea Code No.: BN68-00049A

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 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 resistor-capacitor 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 safety-related 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 may create shock, fire and / or other hazards. Product safety is under review continuously and new instructions are issued whenever appropriate.

SyncMaster 800TFT 1-1

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

1-2-1 General Servicing 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 wriststrap 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 SyncMaster 800TFT

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 components are integrated circuits and some field-effect transistors. The following techniques will reduce the incidence of component damage caused by static electricity.

1-2 Servicing Precautions

WARNING: An electrolytic capacitor installed with the wrong polarity may 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 Specifications

LCD Panel TFT-LCD panel, RGB vertical stripe, normally white transmissive,

18-Inch viewable, 0.28 mm pixel pitch

Scanning Frequency Horizontal : 30 kHz to 81 kHz (Automatic)

Vertical : 56 Hz to 85 Hz (~XGA), 76 Hz (SXGA)

Display Colors 16.7 Million colors

Maximum Resolution Horizontal : 1280 Pixels @ 81 kHz

Vertical : 1024 Pixels @ 76 Hz

Input Video Signal Analog, 0.714 Vp-p ± 5% positive at 75 Ω, internally terminated

Input Sync Signal Type: Seperate H/V sync, Composite H/V, Sync-on-Green

Level: TTL level (V high ≥ 2.0 V, V low ≤ 0.8 V), Sync-on-Green (≤ –0.25 V)

Maximum Pixel Clock rate 135 MHz

Active Display 359 ± 3 mm / Horizontal/Vertical 287.2 ± 3 mm

AC power voltage & Frequency AC 90 to 264 Volts, 60/50 Hz ± 3 Hz

Power Consumption 42 W (max.), 40W (norminal)

Dimensions Unit (W x D x H) 17.7 x 18.2 x 7.2 Inches (449.4 x 461.2 x 182 mm)

Carton (W x D x H) 22.4 x 11.6 x 22.8 Inches (570 x 295 x 580 mm)

Weight (Net/Gross) 8.3 kg (18.28 lbs) / 11.8 kg ( 20.0 lbs)

Environmental Considerations Operating Temperature : 50°F to 104°F (10°C to 35°C)

Humidity : 10 % to 80 % Storage Temperature : -68°F to 113°F (-20°C to 45°C)

Humidity : 5 % to 95 %

• SyncMaster 800TFT complies with SWEDAC (MPR II) recommendations for reduced electromagnetic fields.

• Designs and specifications are subject to change without prior notice.

SyncMaster 800TFT 2-1

Item Description

2 Product Specifications

2-2 SyncMaster 800TFT

2-2 Pin Assignments

Sync Type

Pin No.

15-Pin D-Sub & 13W3 Signal Cable Connector

Separate Composite

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15

Red Green Blue GND DDC Return (GND) GND-R GND-G GND-B No Connection Self Raster GND Bi-Dr Data (SDA) H-Sync V-Sync DDC Clock (SCL)

Red Green Blue GND DDC Return (GND) GND-R GND-G GND-B No Connection Self Raster GND Bi-Dr Data (SDA) H/V-Sync Not Used DDC Clock (SCL)

Red Green + H/V Sync Blue GND DDC Return (GND) GND-R GND-G GND-B No Connection Self Raster GND Bi-Dr Data (SDA) Not Used Not Used DDC Clock (SCL)

13W3

A1 A2 A3 4 4 A1-GND A2-GND A3-GND 3, 8 10 4 6 5 7 1, 2

Sync-on-green

2 Product Specifications

SyncMaster 800TFT 2-3

QRS

Video

Sync

Horizontal

Vertical

CDE

Video

Sync

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

VIDEO

Horizontal

Vertical

H/V Composite Sync

Sync-on-Green

79.976

12.504

1.067

1.837

9.481

0.119

75.025

13.329

0.038

0.475

12.804

0.013

135.000

Positive

Separate

81.129

16.640

6.400

2.880

3.200

76.106

10.660

0.080

3.200

0.020

135.000

Negative

Com.

68.677

14.561

1.016

2.201

10.836

0.508

84.997

11.765

0.044

0.524

11.183

0.015

94.500

Positive

Separate

1024/85Hz

1024x768

1280/76Hz

1280x1024

1280/75Hz

1280x1024

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

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

fH (kHz)

A µsec

B µsec

C µsec

D µsec

E µsec

fV (Hz)

O msec

P msec

Q msec

R msec

S msec

Clock Freq. (MHz)

Polarity H.Sync

V.Sync

Remark

IBM

640/75 Hz

640 x 480

640/85 Hz

640 x 480

800/75 Hz

800 x 600

800/85 Hz

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

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

Separate

43.269

23.111

1.556

2.222

17.778

1.556

85.008

11.764

0.671

0.578

11.093

0.023

49.500

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

Separate

53.674

18.631

1.138

2.702

14.222

0.569

85.061

11.756

0.056

0.503

11.179

0.019

56.250

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

Separate

Mode

VESA

Timing

Green

Horizontal

Vertical

2 Product Specifications

2-4 SyncMaster 800TFT

Memo

3-1-1 Removing the Stand

1. Remove 4 screws on the Stand.

3-1-2 Main Body Disassembly

1. Remove 4 screws on the Rear Cover.

2. Pull the Rear Cover up and off the monitor.

3. Remove 4 screws on the BRKT-VESA and Remove the BRKT-VESA.

4. Remove 16 screws on the PCB Shield and remove the Shield.

5. Remove 7 screws on the Main PCB and 2 screws on the Inverter PCB and 2 screws on the 10P Harness.

6. Disconnect the connector (140P) between the Panel and the CN600 connector on the Main PCB.

7. Disconnect the Function PCB wire (10P) between the Function PCB and the CN102 connector on the Main PCB.

8. Disconnect 2 Inverter wires between the Panel and the CN2, CN3 connectors on the Inverter PCB.

9. Disconnect the 12P harness between CN1 connectors on the Inverter PCB and CN103 connector on the Main PCB.

10. Carefully lift the Main PCB Assembly and Inverter PCB and place them on a flat, level surface that is protected from static electricity.

11. Remove 10 screws on the PCB Bracket.

12. Remove the Bracket Assembly from the Front Cover.

13. Remove the 2 screws on the Function PCB from the Front Cover and remove the Function PCB and Function Knob.

SyncMaster 800TFT 3-1

3 Disassembly and Reassembly

This section of the service manual describes the disassembly and reassembly procedures for the SyncMaster 800TFT TFT-LCD monitor.

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 metal instruments to pry apart the cabinet.

3-2 Reassembly

Reassembly procedures are in the reverse order of Disassembly procedures.

Memo

3 Disassembly and Reassembly

3-2 SyncMaster 800TFT

SyncMaster 800TFT 4-1

4 Alignments and Adjustments

This section of the service manual explains how to use the DDC JIG to adjust the black, red, green, and blue levels of the FPD when you replace the AD Board, and how to update the microprocessor when you change the Panel or Lamp(s).

4-1 Required Equipment

The following equipment is necessary for adjusting the monitor:

• Oscilloscope with probe tool

• Computer with Windows 95 , Windows 98 , or Windows NT .

• DV18AS.exe software

• DDC Control JIG

4-2 Using the DDC Control JIG

After replacing the LCD Panel, Lamp(s), and / or AD Board, use the DDC Control JIG to complete your service. Attach the DDC Control JIG to the flat panel display (FPD) as shown in the diagrams, below.

MONITOR

INTERFACE BOARD VER. 2.0

SIGNAL GENERATOR

3-WIRE CABLE

SIGNAL CABLE

5V DC ADAPTOR

PARALLEL CABLE

Figure 4-1. Setup 1, With Signal Generator

MONITOR

INTERFACE BOARD VER. 2.0

3-WIRE CABLE

SIGNAL CABLE

PARALLEL CABLE

D-SUB CONNECTOR

5V DC ADAPTOR

Figure 4-2. Setup 2, Without Signal Generator

R R R

4-2-1 Main Menu

4-2-1 (a) Service JIG : DV18

4-2-2 Sub Menu

4-2-2 (a) Panel Information

No Label Definition

4 Alignments and Adjustments

4-2 SyncMaster 800TFT

Monitor On Time

Total hours that the monitor has been actively functioning.

Panel Cycle The total number of times the Panel has been

turned ON.

Time Total in Hours that this Panel or Lamp has been

ON. Reset this number to 000000 after replacing the part.

Panel Total number of hours that this Panel has

been ON.

Lamp, Upper Total number of hours that this Upper Lamp

has been ON.

Lamp, Lower Total number of hours that this Lower Lamp

has been ON.

Change No. The number of times this Panel or Lamp has

been replaced. The numbers are 00 if the item is the original factory part installed during manufacture of this monitor.

Panel Replacement times. This value is 00 if original

equipment.

Lamp, Upper Replacement times. This value is 00 if original

equipment.

Lamp, Lower Replacement times. This value is 00 if original

equipment.

Message Shows the message. Read Reads all Panel information data from the

AD Board

Write Writes the Panel Parameter Control values to the

AD Board

Read buffer Reload the Panel Parameter Control values from

the Program buffer

Return Main Returns to the Main menu

Figure 4-4. Control JIG Menu

Red max value Shows the red video signal max value

Green max value Shows the green video signal max value

Blue max value Shows the blue video signal max value

Red min value Shows the red video signal min value

Green min value Shows the green video signal min value

Blue min value Shows the blue video signal min value

Color Automatical screen contrast setting

Auto Adjustment

Red gain control Adjusts the red video signal gain control

Green gain control Adjusts the green video signal gain control

Blue gain control Adjusts the blue video signal gain control

Red cutoff control Adjusts the red video signal cutoff control

Green cutoff control Adjusts the green video signal cutoff control

Blue cutoff control Adjusts the blue video signal cutoff control

Panel information Shows the sub menu to panel information

(4-2-2 (a))

Scroll bar Changes the value or level of the selected

item. The window to the right shows the value as it changes.

SAVE Saves the current adjustment value of

the R,G,B video contrast gain and cutoff level

Setting Displays and allows you to adjust the

PC and Control JIG communication environment. Use this button to change the Delay parameter and Port Address of your PC system and to test the connection between the Control JIG and your computer

Exit Quits the DDC Control JIG

Figure 4-3.Service JIG Menu

1 2 3 4 5 6

8 9

10 11 12 13 14

16 17 18

4 5

10 11 12 13 14

k l

4-2-3 Adjustment Procedures

Use the following procedures whenever you replace the AD Board, Panel, or one or both of the Lamps.

4-2-3 (a) When Replacing the AD Board

1. Before replacing the AD Board, read all Panel information data by using the Read button on the DDC Control JIG.

2. Remove the old AD Board and replace it with a new board.

3. Perform the procedures described in section 4-2-3 (b).

4. Write the Panel information data to the new AD Board by using the Write button.

5. Perform other procedures using the DDC Control JIG, if necessary.

6. When all procedures are complete, select the Exit button ( ) to quit the DDC Control JIG software.

4-2-3 (b) Color Auto Adjustment

1. After displaying 16-Gray pattern or black and white mixed pattern, click “Color Auto Adjustment” button.

2. During normal execution of Auto Algorithm the screen image may flicker. If Auto Algorithm does not excute properly, check DDC Control JIG.

3. After normal execution of Auto Algorithm, confirm optimal settings by observing the contrast of several different patterns on the display.

4. If you want to check each color value, click the button from to and from to

4-2-3 (c) When Replacing the Panel

1. Select the Read Buffer button ( ) to gather the current information about this monitor.

2. Increment the number by clicking on the (+) button on the Panel row in the Change No. column. If they were not already 00, the numbers for the Upper and Lower Lamps will automatically change to 00.

3. Check all values. If there is an error, select Read Buffer again and increment the Change No. column to the correct number. When all values are correct, select the Write button ( ) to record the data in the firmware.

4. Select the Return Menu button ( ) to Return Main Menu.

4-2-3 (d) When Replacing the Upper and/or Lower Lamp

1. Select the Read Buffer button ( ) to gather current information about this monitor.

2. Increment the number by clicking on the (+) button on the Lamp Upper and/or Lamp Lower row in the Change No. column.

3. Check all values. If there is an error, select Read Buffer again and increment the Change No. column to the correct number(s). When all values are correct, select the Write button ( ) to record the data in the firmware.

4. Select the Return Menu button ( ) to Return Main Menu.

4 Alignments and Adjustments

SyncMaster 800TFT 4-3

6 8 13

1. To display the Service Function OSD, push and hold in for 8 seconds the Left and Right arrow buttons on the front panel of the

monitor.

2. If the Panel has been replaced during this servicing, use the Up or Down arrow button on the front panel to highlight the Panel row on the table. Increment the Change No. value by pushing and holding in (for 8 seconds) the Left and Right arrow buttons on the front panel. Incrementing the Panel value automatically changes both the Upper and Lower Lamp Change No. value to 00.

If you have changed the Upper and/or Lower Lamp(s) without changing the Panel, highlight the appropriate row(s) then push and hold in (for 5 seconds) both the Left and Right arrow buttons on the front panel. This action increments the Change No. value(s).

Note: Increment the Lamp value(s) only if one

or both of them were replaced, but the Lamp was not replaced.

3. After incrementing the appropriate values, power off the monitor.

4 Alignments and Adjustments

4-4 SyncMaster 800TFT

4-3 Using the OSD Service function

After replacement of the LCD Panel or Lamp(s), use the 800TFT’s OSD Service Function to complete your service.

Monitor On Time Panel Cycle

Panel Lamp Upper Lamp Lower

: 000049Hr

Service Function

: 000088

: 000050Hr 00 : 000050Hr 00 : 000050Hr 00

Time Change No.

Figure 4-5. Service Function Menu Screen

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