Samsung 940Fn Service manual

SERVICE

Manual

LCD Monitor

Fashion Feature

LCD-Monitor

Chassis LHA19PS Model 940Fn

Lustrous/Colorful Appearance(Design)

- Integrated UI applied

- Built-in Scaler Sync Separator

- Connectivity : Analog (15p Dsub),

Dual (24p DVI-D)

- Power Consumption : 38W

- DPMS : under 1 W (230Vac)

Samsung Electronics Co.,Ltd.

416, Maetan-3Dong, Yeongtong-Gu, Suwon City, Gyeonggi-Do, Korea, 443-742 Printed in Korea P/N : BN82-00136C-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

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

1 Precautions

1-2

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 Static Electricity 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.

1 Precautions

1-3

1. For safety reasons, more than two people are required for carrying the product.

2. Keep the power cord away from any heat emitting devices, as a melted covering may cause fire or electric shock.

3. Do not place the product in areas with poor ventilation such as a bookshelf or closet. The increased internal temperature may cause fire.

4. Bend the external antenna cable when connecting it to the product. This is a measure to protect it from being exposed to moisture. Otherwise, it may cause a fire or electric shock.

5. Make sure to turn the power off and unplug the power cord from the outlet before repositioning the product. Also check the antenna cable or the external connectors if they are fully unplugged. Damage to the cord may cause fire or electric shock.

6. Keep the antenna far away from any high-voltage cables and install it firmly. Contact with the highvoltage cable or the antenna falling over may cause fire or electric shock.

7. When installing the product, leave enough space (10cm) between the product and the wall for ventilation purposes. A rise in temperature within the product may cause fire.

1-4 Installation Precautions

Memo

1 Precautions

1-4

2 Product Specifications

2-1

2 Product Specifications

2-1 Fashion Feature

- Develop Cost Effective Model

- LCD Monitor Standardization/Develop Concept-leading Product

- Develop New Design & Advanced Stand

- Apply integrated GUI for the user's convenience

2-2 LHA19PS Specifications

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

19-Inch viewable, 0.294 (H) x 0.294 (V) mm pixel pitch

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

Vertical : 56 Hz ~ 75 Hz Display Colors 16.7 Million colors Maximum Resolution Horizontal : 1280 Pixels

Vertical : 1024 Pixels Input Video Signal Analog, 0.7 Vp-p positive at 75Ω +/- 10%, internally terminated

Input Sync Signal Type : Seperate H/V sync, Composite H/V, Sync-on-Green (option), automatic

synchronization without external switch of sync type

Level : TTL level Maximum Pixel Clock rate 140 MHz Active Display

Horizontal/Vertical 396 mm / 324 mm AC power voltage & Frequency

AC 100 to 240 VAC(+/- 10%) ,60/50Hz ¡¾ 3Hz Power Consumption 42W (Max) Dimensions

Set (W x D x H) 403.6 x 65.4 x 331.9mm / 15.9 x 2.6 x 13.1inch (with Basic Stand)

Weight (Set) 3.85 kg 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 %

- Design and specifications are subject to change without prior notice.

Description

Item

2 Product Specifications

2-2

Item Item Name CODE.NO Remark

Quick Setup Guide

Warranty Card

(Not available in all

locations)

User's Guide,

Monitor Driver,

Natural Color software,

MagicTune¢â software

MagicRotation software

'DVI-A to D-SUB' Cable

(3EA)

Power Cord (3EA)

DVI Cable (3EA)

BH68-00376L

BH68-70438A

BN59-00486G

BN39-00310B

3903-000042

BN39-00246F

2-3 Option Specification

3 Alignments and Adjustments

3-1

3-1 Required Equipment

The following equipment is necessary for adjusting the monitor:

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

• MTI-2031,2055,2058 DDC Manager Jig are avalable if only #3pin of DVI Port in DDC manager jig should be

connected to GND)

• MTI-2059 is avalable for only using new DDC program(DDC ver : 4.65.12v--20050425)

3-2 Automatic Color Adjustment

To input video, use 16 gray or any pattern using black and white, XGA mode(1024*768@60Hz)

1. Select english for OSD language.

2. Press the " (Enter/Source)" key for 5 seconds.

3-3 DDC EDID Data Input

1. Input DDC EDID data when replacing AD PCB.

2. Receive/Download the proper DDC file for the model from HQ quality control department. Install the below jig (Figure 1) and enter the data.

3-4 OSD Adjustment When Replacing Panel

1. Adjust brightness and contrast to 0. Then, press the (Enter/Source) key for 5 second. Service function OSD will appear on screen.

2. Press the + key to place the cursor on the panel. Press the menu key for 5 seconds.

3-5 OSD Adjustment When Replacing Lamp Only

1. Adjust brightness and contrast to 0. Then, press the exit key for 5 seconds. Service function OSD will appear on the screen.

2. Press the + key. Select upper lamp and press the menu key for 5 seconds. Then, select lower lamp and press the menu key for 5 seconds.

-Note : Please be sure to read the following instructions for details on service function.

3 Alignments and Adjustments

This section of the service manual explains how to use the RS232 JIG. This function is needed for AD board change and program memory (IC110) change.

031

Figure 1.

TI-2

DDC Manager

Parallel Connector

(25P Cable)

Connect Monitor

(Signal Cable)

3 Alignments and Adjustments

3-2

3-6 Ser vice Function Spec.

3-6-1 How to Display Service Function OSD

1. The value for brightness and contrast should be changed to zero.

2. Within 5 seconds, press the (Enter/Source) key.

3. Service function OSD will be displayed.

-If you want to disable the service function OSD, you will have to power off.

Figure 2. The example of service function OSD

Figure 3.

Panel Information

Softward Version Checksum

The service function OSD is based on a grid of 29 columns x 12 rows. The service function OSD consists of panel information, software version and MICOM checksum.

3-6-2 How to Control Service Function OSD

1. With the panel selected on OSD, whenever you press the right key, the base color will change to blue from "Panel" to "Upper Lamp", "Lower Lamp".

3 Alignments and Adjustments

3-3

Figure 4.

3-6-3 How to Control Service Function OSD

•After change the panel or lamp, you must reset service function OSD.

•The case of panel change

After changeing the panel, press the menu key within 5 seconds,. Then, panel Ch. No increases one step and the panel time information is reset to zero. Simultaneously, other information is reset to zero (Upper/Lower lamp, Panel cycle).

Figure 5, 6.

3-6-4 How to Control Service Function OSD

•In the case of Upper Lamp or Lower Lamp change

After changeing the Upper Lamp or Lower Lamp,

1. Select the Upper Lamp or Lower Lamp

2. Press the Menu key within an 5 seconds.

Then, Ch. No and time will be reset to zero (selected item only).

3 Alignments and Adjustments

3-4

3-7 How to execute DDC

1. Open file.

2. Select Port #1.

3. Select DDC file.

4.Click, "Next" Button

5. Type in the monitor serial number and press Enter. *Repeat this step 2 to 5 times in digital inputs after the analog input.

4 Troubleshooting

4-1

4 Troubleshooting

’

•

• “ ”

4-1 No Power

When pin4 of CN600 is 0V does proper DC 5V appear at Pin 6.7 of CN600 separately?

Change IP Board.

Yes

When pin1 of IC600 is 5V

does proper DC 3.3V appear

at Pin 3 of IC600

Check IC600 related circuit

Yes

Does proper DC 3.3V appear

at pin of IC200

Check IC200 and related circuit

When pin3 of IC601,IC602

is 5V does proper DC 1.8V

appear at Pin 3 of IC601,

IC602 ?

Check IC601,IC602 related circuit

4 Troubleshooting

4-2

Do X401,X901 oscillate

like as figure 1 properly?

4-2 No Video (Analog)

Replace or check related circuit

check signal cable connection

and power

Yes

Is there R,G,B input at R11,R106,R108,R117,

R116,R115?

Check input part.

Yes

Do Hsync,Vsync waveformgnal

appear at R147,R830,R142,R145 ?

check input part

Yes

Does sync signal(figure 2,3) appear

at Pin 1, pin100 of IC400

check IC400 and related circuit

Yes

Does sync signal(figure 2,3)

appear at pin43,pin44 of IC200?

check IC200 and related circuit

Yes

Does the output signal appear at Pin 17 ~ 20,

22 ~ 27 of CN400?

check IC 400 and related circuit

Yes

Does DC 5V appear at pin

28,29,30 of CN400?

check the panel_En signal and

BL_En signal and related circuit

Yes

Replace LCD Panel.

2 3

4 Troubleshooting

4-3

WAVEFORMS

4 Troubleshooting

4-4

Do X401,X901 oscillate

like as figure 1 properly?

4-3 No Video (Digital)

Replace or check related circuit

check signal cable connection

and power

Yes

Is there R,G,B input at

R126 ~ R131 like as figure

4,5,6?

check input part

Yes

Is there waveform figure 7

at R132,R133,R140,R141?

check input part

Yes

Does the output signal appear at Pin

17 ~ 20, 22 ~ 27 of CN400?

check IC 400 and related circuit

Yes

Does DC 5V appear at pin

28,29,30 of CN400?

check the panel_En signal and

BL_En signal and related circuit

Yes

Replace LCD Panel.

4 5

4 Troubleshooting

4-5

1 4

5 6

WAVEFORMS

Memo

4 Troubleshooting

4-6

5 Exploded View & Parts List

5-1

5 Exploded View and Parts List

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

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

5-1 Exploded View

M0112

T0003

T0022

T0145

M0215

M0006

CIS

M0174

T0077

M0107

M0006

T0003

5 Exploded View & Parts List

5-2

Location Code.No Item & Specification Q'ty SA/SNA Remark

T0003 BN96-02239C ASSY COVER P-FRONT;HA19Fn,ABS HB,GR70,SI 1 SA

M0112 BN63-01967B COVER-FRONT;HA19TS,ABS,T1.5,403.2,331.9, 1 SNA

T0022 BN64-00377B KNOB CONTROL;HA17TS,PC CLEAR,T2.1,9,112, 1 SNA

M0145 BN96-02474C ASSY BOARD P-FUNCTION;HAYDN,YWP-VD-05-05 1 SA

M0215 BN07-00224A LCD-PANEL;M190EN03,Matisse,8BIT,396*324* 1 SA

M0006 BN63-02254A COVER-REAR;HA19Fn,HIPS,2.0,HB,BK24,2 DVI 1 SA

M0107 BN63-01974C SHIELD-COVER;HA19Fn,SECC,T0.8,398,222,2D 1 SNA

T0077 BN41-00633A PCB MAIN;HAYDN,FR4,2L,MP1.0,0.6T,105*8,1 1 SNA

M0174 BN44-00124C IP BOARD;IP-35135B (H),BI17VS,3.0 ~4.0mA 1 SA

CIS BN63-01781A SHIELD-LAMP;BI19BS,SPTE,T0.3 1 SNA

T0003 BN96-02239C ASSY COVER P-FRONT;HA19Fn,ABS HB,GR70,SI 1 SA

M0006 BN63-02254A COVER-REAR;HA19Fn,HIPS,2.0,HB,BK24,2 DVI 1 SA

5-2 Parts List

+ 46 hidden pages