Dell 1908FPC User manual

19" LCD Color Monitor Dell 1908FPC
1
Service
Service
Service
HorizontalFrequency
30kHzto81kHz
Table of Contents
Description Page Description Page
SAFETY NOTICE
ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE
CHASSIS AND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING
ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.
7. Schematic Diagram………………..............................31
7.1 Main Board..........…………......................................31
7.2 Power Board……………....................................36
7.3 USB Board……….…….……………………………..38
7.4 Key Board…………………….……………………….40
8. PCB Layout......................…......................................41
8.1. Main Board………………........................................41
8.2. Power Board…….………........................................43
8.3. Key Board………………….....................................44
8.4 USB Board……..………………………………………45
9. Maintainability…..……….......................................46
9.1.Equipments and Tools Requirement.…….…...........46
9.2.Trouble Shooting…………………............................48
10.White-Balance, Luminance adjustment...……......53
11.ISP Instruction…………….…….................................54
12. Monitor Exploded View…………….………............60
13. BOM List…………....................................................61
14. Different Parts List…………………….……………...77
CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING
Table Of Contents.......…….................……...........…........1
Revision List.….........................………................……......2
Important Safety Notice.….……….…..................……......3
1.Monitor Specifications.....…........................………........4
2.LCD Monitor Description…………………………….......5
3.Operation Instructions……………...............……...........6
3.1.General Instructions…………………………………….6
3.2.Control Buttons……………...............……...............7
3.3 Adjusting the Picture...........…………….........………..9
4. Input/Output Specification.............……………........…15
4.1.Input Signal Connector............………….................15
4.2.Factory Preset Display Modes...…..…......................16
4.3.Power Supply Requirements..........……...................16
4.4.Panel Specification…….....……………..................17
4.5.Definition of Pixel Defects…………...............……….18
5.Block Diagram…….…...................…………................20
5.1.Software Flow Chart………..………………....….......20
5.2.Electrical Block Diagram………………..…..….......22
6. Mechanical Instructions…..........................................24

19" LCD Color Monitor Dell 1908FPC
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Revision List
Revision Release Date Revise history TPV model
A00 Jan.-08-2006 Initial Release
T96GGCHKFDDGDP
T96GGCHKFDDEDP
T96SGCHKFDDEDP
T96SGCHKFDDFDP
T96SGCHKFDDGDP
T96SGCHKFDDMDP
A01 FEB-01-2007 Add the torque setting at page 49 All

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Important Safety Notice
Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service
procedures recommended by AOC and described in this service manual are effective methods of performing
service operations. Some of these service operations require the use of tools specially designed for the purpose.
The special tools should be used when and as recommended.
It is important to note that this manual contains various CAUTIONS and NOTICES which should be carefully read
in order to minimize the risk of personal injury to service personnel. The possibility exists that improper service
methods may damage the equipment. It is also important to understand that these CAUTIONS and NOTICES ARE
NOT EXHAUSTIVE. AOC could not possibly know, evaluate and advise the service trade of all conceivable ways in
which service might be done or of the possible hazardous consequences of each way. Consequently, AOC has not
undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not
recommended by AOC must first satisfy himself thoroughly that neither his safety nor the safe operation of the
equipment will be jeopardized by the service method selected.
Hereafter throughout this manual, AOC Company will be referred to as AOC.
WARNING
Use of substitute replacement parts, which do not have the same, specified safety characteristics may create
shock, fire, or other hazards.
Under no circumstances should the original design be modified or altered without written permission from AOC.
AOC assumes no liability, express or implied, arising out of any unauthorized modification of design.
Servicer assumes all liability.
FOR PRODUCTS CONTAINING LASER:
DANGER-Invisible laser radiation when open. AVOID DIRECT EXPOSURE TO BEAM.
CAUTION-Use of controls or adjustments or performance of procedures other than those specified herein may
result in hazardous radiation exposure.
CAUTION -The use of optical instruments with this product will increase eye hazard.
TO ENSURE THE CONTINUED RELIABILITY OF THIS PRODUCT, USE ONLY ORIGINAL MANUFACTURER'S
REPLACEMENT PARTS, WHICH ARE LISTED WITH THEIR PART NUMBERS IN THE PARTS LIST SECTION
OF THIS SERVICE MANUAL.
Take care during handling the LCD module with backlight unit
-Must mount the module using mounting holes arranged in four corners.
-Do not press on the panel, edge of the frame strongly or electric shock as this will result in damage to the screen.
-Do not scratch or press on the panel with any sharp objects, such as pencil or pen as this may result in damage to
the panel.
-Protect the module from the ESD as it may damage the electronic circuit (C-MOS).
-Make certain that treatment person’s body is grounded through wristband.
-Do not leave the module in high temperature and in areas of high humidity for a long time.
-Avoid contact with water as it may a short circuit within the module.
-If the surface of panel becomes dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth
may damage the panel.)

19" LCD Color Monitor Dell 1908FPC
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1. Monitor Specifications
Screen type Active matrix - TFT LCD
Panel Type LM190E08-TLB2 LPL
Size 19 inches (19-inch viewable image size)
Pixel pitch 0.294 mm
Viewable angle 160° (vertical) typ, 160° (horizontal) typ
LCD Panel
Response time 5ms typical
Video R, G, B Analog Interface, DVI digital Interface
Separate Sync H/V TTL
H-Frequency 30 kHz to 81 kHz (automatic)
Input
V-Frequency 56 Hz to 76 Hz (automatic)
Display Colors 16.7M
Dot Clock 165MHz (Max.)
Max. Resolution 1280 x 1024 at 75 Hz
Plug & Play VESA DDC
ON Mode 35 W (typical)
EPA ENERGY
STAR®OFF Mode <1W
Input Connector 15-pin D-subminiature, blue connector;
DVI-D, white connector
Maximum Screen Size Horizontal : 473.76 mm (18.65 inches)
Vertical: 296.1 mm (11.66 inches)
Power Source 100 to 240 VAC / 50 or 60 Hz + 3 Hz / 2.0A (Max.)
Environmental
Considerations
Operating Temp: 5° to 35°C
Operating Humidity: 10% to 80%
Storage Temp.: -20° to 60°C
Weight
Weight with packaging: 16.3 lbs (7.4kg)
Weight with stand assembly and cables: 12.64 lbs (5.74 kg)
Weight without stand assembly: 8.81 lbs (4 kg)
Weight of stand assembly: 3.75 lbs (1.7 kg)

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2. LCD Monitor Description
The LCD monitor will contain a main board, power board, key board, which house the flat panel control logic,
brightness control logic and DDC.
The power board will provide AC to DC Inverter voltage to drive the backlight of panel and the main board chips
each voltage.
Video signal, DDC
Power board
Flat Panel and
CCFL backlight
Main Board
Key board
RS232 Connector
For white balance
adjustment in factory
mode
CCFL Drive.
AC-IN
100-240V
Monitor Block Diagram
Host Computer

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3. Operation instructions
3.1 General Instructions
NOTE: If you change the settings and then either proceed to another menu or exit the OSD menu, the
monitor automatically saves those changes. The changes are also saved if you change the settings and then
wait for the OSD menu to disappear.
1. Push the MENU button to open the OSD menu and display the main menu.
Main Menu for Analog (VGA) Input Main Menu for digital (DVI) Input
Main Menu for Analog (VGA) Input Main Menu for Digital (DVI) Input
or
or

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NOTE: Auto Adjust, Positioning and Image Settings are only available when you are using the analog (VGA)
connector.
2. Push the - and + buttons to move between the setting options. As you move from one icon to another, the option
name is highlighted. See the table below for a complete list of all the options available for the monitor.
3. Push the MENU button once to activate the highlighted option.
4. Push - and + button to select the desired parameter.
5. Push MENU to enter the slide bar and then use the - and + buttons, according to the indicators on the menu, to
make your changes.
6. Push the MENU button once to return to the main menu to select another option or push the MENU button two
or three times to exit from the OSD menu.
When the OSD is locked, pressing the menu button takes the user directly to the OSD settings menu, with OSD
Lock selected. Select No (-) to unlock and allow user access to all applicable settings.
3.2 Control Buttons
1
Video input select
Use the Input Select button to select between two different video
signals that may be connected to your monitor.
If both VGA and DVI caables are connected to one PC, this monitor
will display an image automatically just as long as a video signal is
present in either VGA or DVI outputs. When connecting one display to
two PCs, if using screen savers, best to set both to the exact times.
Whichever mouse is moved first will activate that video input first.
NOTE: The floating 'Dell Self-test Feature Check' dialog
appears on a black background if the monitor cannot sense a video
signal. Using the input select button, select the desired input to be
tested either Analog Input or Digital Input. Disconnect the video cable
from the video card and the Dell Self-test Feature Check dialogue box
will appear if the display is operating correctly.

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2
OSD menu / select
The Menu button is used to open and exit the on-screen display
(OSD), and exit from menus and sub-menus. See Using the OSD
Menu.
3
Brightness Menu
Use this button to launch Brightness menu.
3,4
Down (-) and Up (+)
Use these buttons to adjust (decrease/increase ranges) items in the
OSD menu.
4
Auto Adjust
Use this button to activate automatic setup and adjustment. The
following dialog appears on a black screen as the monitor self-adjusts
to the current input:
Auto Adjust In Progress
Auto Adjustment button allows the monitor to self-adjust to the
incoming video signal. After using Auto Adjustment, you can further
tune your monitor by using the Pixel Clock (Coarse), Phase (Fine)
controls in the OSD.
NOTE: Auto Adjust does not occur if you press the button while
there are no active video input signals or attached cables.
or
or

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5
Power Button and Indicator
Use the power button to turn the monitor on and off.
The green light indicates the monitor is on and fully functional. An
amber light indicates power save mode.
3.3 Adjusting the Picture
Icon Menu and
Submenus Description
Exit Select to exit the Main menu.
Brightness/
Contrast
Brightness adjusts the luminance of the backlight.
Adjust Brightness first, then adjust Contrast only if further adjustment is necessary.
Push the + button to increase luminance and push the - button to decrease
luminance (min 0 ~ max 100).
Contrast adjusts the degree of difference between darkness and lightness on the
monitor screen.
Push the + button to increase the contrast and push the - button to decrease the
contrast (min 0 ~ max 100).
Positioning:
Horizontal
Vertical
Positioning moves the viewing area around on the monitor screen.
When making changes to either the Horizontal or Vertical settings, no changes
occur to the size of the viewing area. The image shifts in response to your
selection.
Minimum is 0 (-) and maximum is 100 (+).
NOTE: When using DVI source, the Positioning option is not available.

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Auto Adjust Even though your computer recognizes your monitor on startup, the Auto
Adjustment function optimizes the display settings for use with your particular
setup.
Select to activate automatic setup and adjustment. The following dialog appears
on a black screen as the monitor self-adjusts to the current input:
Auto Adjust In Progress
Auto Adjustment allows the monitor to self-adjust to the incoming video signal.
After using Auto Adjustment, you can further tune your monitor by using the Pixel
Clock (Coarse) and Phase (Fine) controls under Image Settings.
NOTE: In most cases, Auto Adjust produces the best image for your
configuration.
Image settings:
Pixel Clock
(Coarse)
Phase (Fine)
The Phase and Pixel Clock adjustments allow you to more closely adjust your
monitor to your preference. These settings are accessed through the main OSD
menu, by selecting Image Settings.
Use the - and + buttons to make adjustments. (Minimum: 0 ~ Maximum: 100)
If satisfactory results are not obtained using the Phase adjustment, use Pixel
Clock (Coarse) and then use Phase (fine), again.
NOTE: This function may change the width of the display image. Use the
Horizontal function of the Position menu to center the display image on the
screen.
NOTE: When using DVI source, the Image Settings option is not available.
Color Settings
Color Settings adjusts the color temperature, color hue, and saturation.
The color hue is most noticeable in areas of white.

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Normal Preset
Blue Preset
Red Preset
User Preset
Normal Preset is selected to obtain the default (factory) color settings. This setting
is also the “sRGB” standard default color space.
Blue Preset is selected to obtain a bluish tint. This color setting is typically used for
text based applications (spreadsheets, programming, text editors, etc.).
Red Preset is selected to obtain a redder tint. This color setting is typically used
for color-intensive applications (photograph image editing, multimedia, movies,
etc.).
User Preset: Use the plus and minus buttons to increase or decrease each of the
three colors (R, G, B) independently, in single digit increments, from 0 to 100.
OSD Settings:
Horizontal
Position
Vertical Position
OSD Hold Time
OSD Lock
Adjust the settings for the OSD, including the location, the amount of time the
menu remains on-screen, and the rotation of the OSD.
Position of the OSD:
●To adjust the horizontal position of the OSD, use the - and + buttons, and move
OSD to the left and right.
●To adjust the vertical position of the OSD, use the - and + buttons, and move
OSD down and up.
OSD Hold Time:
The OSD stays active for as long as it is in use. Adjusting the hold time, sets the
length of time the OSD remains active after the last time you pressed a button.
Use the - and + buttons to adjust the slider in 5 second increments, from 5 to 60
seconds.
OSD Lock:
Controls user access to adjustments. When Yes (+) is selected, no user
adjustments are allowed. All buttons are locked except the menu button.
NOTE: When the OSD is locked, pressing the menu button takes the user
directly to the OSD settings menu, with OSD Lock selected. Select No (-) to unlock
and allow user access to all applicable settings.

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NOTE: You can also lock or unlock the OSD by pushing and holding the
Menu button for 15 seconds.
Language Select to have the OSD display in one of five languages (English, French,
Spanish, German, or Japanese).
NOTE: The change only affects the OSD. It has no effect on any software
running on the computer.
Audio (optional) You can select to have the audio on or off when the monitor is in power saving
mode.
Yes — enables audio
No — disables audio (default)
Factory Reset: Reset the OSD menu options to the factory preset values.
Exit — Select to exit out of Reset to Factory Settings menu without resetting any
OSD options.
Position settings only — Change the settings for Image Position back to original
factory settings.
Color settings only — Change the Red, Green, and Blue settings back to their
original factory settings and set the default setting for Normal Preset.
All settings — Change all the user-adjustable settings including color, position,

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brightness, and contrast and OSD hold time to the factory defaults. The language
of the OSD does not change.
IR — This feature will help reduce minor cases of image retention.
Enable LCD Conditioning: If an image appears to be stuck on the monitor, select
LCD Conditioning to help eliminate any image retention. Using the LCD
Conditioning feature may take several hours. Severe cases of image retention are
known as burn-in, the LCD Conditioning feature does not remove burn-in.
NOTE: Use LCD Conditioning only when you experience a problem with
image retention.
Below warning message appears once user select “Enable LCD Conditioning”:
NOTE: Press any button on the monitor to terminate LCD Conditioning at any
time.
DDC/CI — Enable the DDC/CI control function.
DDC/CI (Display Data Channel/Command Interface) allows you to adjust the
monitor parameters (brightness, color balance, etc) via software applications on
your PC.
Default is "Enable". You can disable this feature by selecting "Disable".
For best user experience and optimum performance of your monitor, keep this
feature enabled.
NOTE: If user select "Disable", display Warning message box as below.
Select "Yes" disables DDC/CI and return to "Factory Reset" menu. Warning
message time-out in 20 sec.

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or
or
OSD Warning Messages
One of the following warning messages may appear on the screen indicating that the monitor is out of
synchronization.
This means that the monitor cannot synchronize with the signal that it is receiving from the computer. Either the
signal is too high or too low for the monitor to use. See specifications for the Horizontal and Vertical frequency
ranges addressable by this monitor. Recommended mode is 1280 X 1024 @ 60Hz.
NOTE: The floating Dell Self-test Feature Check dialog appears on-screen if the monitor cannot sense a
video signal.
Occasionally, no warning message appears, but the screen is blank. This could also indicate that the monitor is not
synchronizing with the computer.
1. Auto Detect (Digital Input)
Cannot Display This Video Mode
Optimum Resolution 1280 x1024 60Hz
1. Auto Detect (Analog Input)
Cannot Display This Video Mode
Optimum Resolution 1280 x1024 60Hz
or
3. Digital Input
Cannot Display This Video Mode
Optimum Resolution 1280 x1024 60Hz
2. Analog Input
Cannot Display This Video Mode
Optimum Resolution 1280 x1024 60Hz
or

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4. Input/Output Specification
4.1 Input Signal Connector
VGA Connector:
Pin No. Description Pin No. Description
1. Red Video 9. DDC +5V
2. Green Video 10. GND-sync
3. Blue Video 11. GND
4. GND 12. DDC data
5. Self-test 13. H-Sync
6. R-Ground 14. V-Sync
7. G-Ground 15. DDC clock
8. B-Ground
VGA Connector layout
DVI Connector:
Note: Pin 1 is at the top right.
Pin Signal Assignment Pin Signal Assignment Pin Signal Assignment
1 T.M.D.S. Data 2- 9 T.M.D.S. Data 1- 17 T.M.D.S. Data 0-
2 T.M.D.S. Data 2+ 10 T.M.D.S. Data 1+ 18 T.M.D.S. Data 0+
3 T.M.D.S. Data 2 Shield 11 T.M.D.S. Data 1 Shield 19 T.M.D.S. Data 0 Shield
4 No Pin 12 No Pin 20 No Pin
5 No Pin 13 No Pin 21 No Pin
6 DDC Clock 14 +5V Power 22 T.M.D.S. Clock Shield
7 DDC Data 15 Ground (for +5V) 23 T.M.D.S. Clock +
8 No Connect 16 Hot Plug Detect 24 T.M.D.S. Clock -

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Universal Serial Bus (USB) Interface
This monitor supports High-Speed Certified USB 2.0 interface.
USB ports:
•1 upstream - rear
•4 downstream - 2 on rear; 2 on left side
4.2 Factory Preset Display Modes
4.3 Power Supply Requirements
A/C Line voltage range : 100 V ~ 240 V
A/C Line frequency range : 50 ±3Hz, 60 ±3Hz
Current : 1.5A max at 100V; 0.8A max at 240 V
Peak surge current : < 60A peak at 240 VAC and cold starting
Leakage current : < 3.5mA
Power line surge : No advance effects (no loss of information or defect)
with a maximum of 1 half-wave missing per second
DC output Voltage : 5VDC ± 5％; 13VDC± 10％,12VDC± 5％
Data Rate Power Consumption
High speed 480 Mbps 2.5W (Max., each port)
Full speed 12 Mbps 2.5W (Max., each port)
Low speed 1.5 Mbps 2.5W (Max., each port)

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4.4 Panel Specification
M220Z1-L01C1 ZBD
4.4.1 Display Characteristics
4.4.2 Optical Characteristics
Ta= 25°C, VLCD=5.0V, fV=60Hz, fCLK=54MHz, IBL=7.5mA

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4.5 Definition of Pixel Defects
4.5. 1.Description
These inspection standards shall be applied to LCD Module supplied by CHI MEI Optoelectronics Corporation.
4.5.2 The environmental condition of inspection
The environmental condition and visual inspection shall be conducted as below.
Ambient conditions
a. Temperature: 25±5 ℃
b. Humidity: 65 ±10% RH
c. Illumination: Single 20W fluorescent lamp non-directive
(300 to 700 Lux)
Viewing distance
The distance between the LCM and the inspector’s eyes shall be at least 30-50㎝.
Viewing Angle
The inspection shall be conducted within normal viewing angle range.
Refer to the CAS for viewing angle.※
4.5.3. Dot Defect
Bright Dot
Dots (sub-pixels) which appeared brightly in the screen when the LCM displayed with Full Black pattern.
-R, G or B 1 dot ---------------------------------0 Max
-Adjacent 2 dots --------------------------------0 Max
-Total amount of Bright dots --------------------0 Max
Partial Bright Dot
-Partial bright dot (tiny dot) --------------------5 Max
* Bright dot and Partial dot definition is referred to the Appendix B
Dark Dot
Dots (sub-pixels) which appeared darkly in the screen when the LCM displayed with bright pattern.
-1 dot --------------------------------------------5 Max
-Adjacent 2 dots --------------------------------2 Max
-Adjacent 3 dots --------------------------------1 Max
-Total amount of Dark dot ----------------------5 Max
-Minimum distance of Dark dots ---------------5mm
Total amount of Dot Defects --------------------5 Max (except Partial bright dot)
4.5.4. Polarizer Defects

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Note) continued
c. Extraneous substances which can be wiped out, like Finger Print, Particles, are not considered as a defect.
b. Defects which is on the Black Matrix(outside of Active Area) are not considered asa defect.
4.5.5 Foreign Material
* Maximum allowable number of defects for 3.2 & 3.3 : N<=8
4.5.6. Line Defect
All kinds of line defects such as vertical, horizontal or cross are not allowed.
4.5.7. Bezel Appearance
Scratches, minor bents, stains, particles on the Bezel frame are not considered as a defect.
4.5.8. Others
Issues which is not defined in these criteria shall be discussed with both parties, Customer and Supplier, for better
solution.

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5. Block Diagram
5.1 Software Flow Chart
1
2
N
Y
5
Y
N
10
Y
N
12
Y
N
7
Y
N
6
4
3
8
9
14
11
13
Y
N
15
Y
N
16
17
19
Y
N
18