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COLOR MONITOR
SERVICE MANUAL
CHASSIS NO. : CL-29
FACTORY MODEL: LB801H
MODEL: L1811B(LB801H-GL)
*( ) ID LABEL MODEL No.

CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
L1811B
CONTENTS
SPECIFICATIONS ................................................... 2 ADJUSTMENT ...................................................... 12
PRECAUTIONS ....................................................... 4 TROUBLESHOOTING GUIDE .............................. 13
TIMING CHART ....................................................... 5 PRINTED CIRCUIT BOARD................................... 18
OPERATING INSTRUCTIONS ................................ 6 EXPLODED VIEW...................................................22
WIRING DIAGRAM ................................................. 8 REPLACEMENT PARTS LIST ...............................24
BLOCK DIAGRAM ................................................... 9 PIN CONFIGURATION............................................30
DESCRIPTION OF BLOCK DIAGRAM...................10 SCHEMATIC DIAGRAM ......................................... 32

SPECIFICATIONS
1. LCD CHARACTERISTICS 4. POWER SUPPLY
Type : TFT SXGA LCD
Size : 18inch 4-1. Power Adaptor(Built-in Power)
Pixel Pitch : 0.2805(H) x 0.2805(V) Input : AC 100~240V, 50/60Hz , 1.0A
Color Depth : 8-bit, 16,777,216 colors 4-2. Power Consumption
Electrical Interface : LVDS MODE H/V SYNC VIDEO POWER CONSUMPTION LED COLOR
Surface Treatment : Anti-Glare, Hard Coating(3H)
POWER ON (NORMAL) ON/ON ACTIVE less than 53 W GREEN
Operating Mode : Normally Black
Backlight Unit : Six-CCFL (Cold Cathode STAND-BY OFF/ON OFF less than 3 W AMBER
Fluorescent Lamp) SUSPEND ON/OFF OFF less than 3 W AMBER

OFF OFF/OFF OFF less than 3 W AMBER
2. OPTICAL CHARACTERISTICS
2-1. Viewing Angle by Contrast Ratio 10 POWER OFF - - less than 3 W OFF
Left : -60° min., -80°(Typ)
Right : +60° min., +80°(Typ) 5. ENVIRONMENT
Top : +60° min., +80°(Typ) 5-1. Operating Temperature: 10°C~35°C (50°F~95°F)
Bottom : -60° min., -80°(Typ) (Ambient)
5-2. Relative Humidity : 10%~80%
2-2. Luminance : 200(min), 250(Typ) (Non-condensing)
2-3. Contrast Ratio : 200(min), 350(Typ) 5-3. MTBF : 50,000 Hours(Min)

3. SIGNAL (Refer to the Timing Chart) 6. DIMENSIONS (with TILT/SWIVEL)
3-1. Sync Signal
· Type : Separate, Positive/Negative Width : 406 mm (15.98'')
Composite, SOG (Sync On Green) Depth : 223 mm (8.78')
Digital Height : 431 mm (16.97'')
3-2. Video Input Signal
7. WEIGHT (with TILT/SWIVEL)
1) Type : R, G, B Analog
2) Voltage Level : 0~0.71 V Net. Weight : 7.8kg (17.19 lbs)
a) Color 0, 0 : 0 Vp-p Gross Weight : 10.0kg (22.04 lbs)
b) Color 7, 0 : 0.467 Vp-p
c) Color 15, 0 : 0.714 Vp-p 8. USB
3) Input Impedance : 75 Upstream : 1 port, Downstream : 2 port
Speed : Full-12Mbps, Low-1.5Mbps
3-3. Operating Frequency
Horizontal : 30 ~ 80kHz
Vertical : 56 ~ 85Hz




-2-
Signal Connector Pin Assignment


· DVI-I Connector (Digital/Analog)
Pin Signal (DVI-I) Pin Signal (DVI-I)
1 T. M. D. S. Data2- 16 Hot Plug Detect
8 C1 C2 2 T. M. D. S. Data2+ 17 T. M. D. S. Data0-
1
9 16 C5 3 T. M. D. S. Data2/4 Shield 18 T. M. D. S. Data0+
17 24 C3 C4 4 T. M. D. S. Data4- 19 T. M. D. S. Data0/5 Shield
5 T. M. D. S. Data4+ 20 T. M. D. S. Data5-
6 DDC Clock 21 T. M. D. S. Data5+
7 DDC Data 22 T. M. D. S. Clock Shield
8 Analog Vertical Sync. 23 T. M. D. S. Clock+
9 T. M. D. S. Data1- 24 T. M. D. S. Clock-
10 T. M. D. S. Data1+ C1 Analog Red
11 T. M. D. S. Data1/3 Shield C2 Analog Green
12 T. M. D. S. Data3- C3 Analog Blue
13 T. M. D. S. Data3+ C4 Analog H. Sync.
14 +5V Power C5 Analog Ground
15 Ground (return for +5V,
H. Sync. and V. Sync.)

T. M. D. S. (Transition Minimized Differential Signaling)




-3-
PRECAUTION
WARNING FOR THE SAFETY-RELATED COMPONENT. WARNING
· There are some special components used in LCD BE CAREFUL ELECTRIC SHOCK !
monitor that are important for safety. These parts are
· If you want to replace with the new backlight (CCFL) or
marked on the schematic diagram and the
inverter circuit, must disconnect the AC adapter
replacement parts list. It is essential that these critical
because high voltage appears at inverter circuit about
parts should be replaced with the manufacturer's
650Vrms.
specified parts to prevent electric shock, fire or other
hazard.
· Handle with care wires or connectors of the inverter
· Do not modify original design without obtaining written circuit. If the wires are pressed cause short and may
permission from manufacturer or you will void the burn or take fire.
original parts and labor guarantee.


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 are
grounded through wrist band.
· Do not leave the module in high temperature and in
areas of high humidity for a long time.
· The module not be exposed to the direct sunlight.
· Avoid contact with water as it may a short circuit within
the module.
· If the surface of panel become dirty, please wipe it off
with a softmaterial. (Cleaning with a dirty or rough cloth
may damage the panel.)

CAUTION
Please use only a plastic screwdriver to protect yourself
from shock hazard during service operation.




-4-
TIMING CHART

VIDEO
B A


E
C
F
D
SYNC



<< Dot Clock (MHz), Horizontal Frequency (kHz), Vertical Frequency (Hz), Horizontal etc... (µs), Vertical etc... (ms) >>
H/V Sync Dot Total Period Video Active Time Front Porch Sync Duration Back Porch
Mode Clock Frequency Resolution
Sort Polarity (E) (A) (C) (D) (F)
H + 31.469 800 640 16 96 48 640x350
1 25.175
V ­ 70.8 449 350 38 2 59 70Hz
H ­ 31.468 900 720 18 108 54 720x400
2 28.321
V + 70.8 449 400 12 2 35 70Hz
H ­ 31.469 840 640 16 96 48 640x480
3 25.175
V ­ 59.94 525 480 10 2 33 60Hz
H ­ 37.5 840 640 16 64 120 640x480
4 31.5
V ­ 75 500 480 1 3 16 75Hz
H ­ 43.269 832 640 56 56 80 640x480
5 36.0 85Hz
V ­ 85.0 509 480 1 3 25
H + 37.879 1056 800 40 128 88 800x600
6 40.0
V + 60.317 628 600 1 4 23 60Hz
H + 46.875 1056 800 16 80 160 800x600
7 49.5
V + 75.0 625 600 1 3 21 75Hz
H + 53.674 1048 800 32 64 152 800x600
8 56.25 85Hz
V + 85.061 631 600 1 3 27
H +/­ 49.725 1152 832 32 64 224 832x624
9 57.283 75Hz
V +/­ 74.55 667 624 1 3 39
H ­ 48.363 1344 1024 24 136 160 1024x768
10 65.0 60Hz
V ­ 60.0 806 768 3 6 29
H ­ 60.123 1312 1024 16 96 176 1024x768
11 78.75 75Hz
V ­ 75.029 800 768 1 3 28
H + 68.677 1376 1024 48 96 208 1024x768
12 94.5 85Hz
V + 84.997 808 768 1 3 36
H +/­ 68.681 1456 1152 32 128 144 1152x870
13 100.0 75Hz
V +/­ 75.062 915 870 3 3 39
H +/­ 61.805 1504 1125 18 134 200 1152x900
14 92.978 65Hz
V +/­ 65.96 937 900 2 4 31
H + 63.981 1688 1280 48 112 248 1280x1024
15 108.0 60Hz
V + 60.02 1066 1024 1 3 38
H + 79.976 1688 1280 16 144 248 1280x1024
16 135.0
V + 75.035 1066 1024 1 3 38 75Hz


-5-
OPERATING INSTRUCTIONS

FRONT VIEW REAR VIEW



L1811B




Power Connect




Front Control Panel USB Port
DVI Connect D-Sub Signal
Connect

Front Control Panel




6 3 4 5 1 2




1. Power ON/OFF Button 4. Button
Use this button to turn the monitor on or off. Use these buttons to choose or adjust items in the On Screen
Display.
2. Power Indicator
This indicator lights up green when the monitor
5. AUTO/SELECT Button
operates normally. If the display is in DPM(Energy
Use this button to enter a selection in the On Screen Display.
Saving)mode, this indicator color change to amber.
6. SOURCE Button
3. MENU Button
Use this button to make Dsub or DVI connector active.
Use these buttons to enter or exit the On Screen Display.
This feature is used when two computers are connected to the
monitor. The default setting is Dsub.




-6-
Making use of USB (Universal Serial Bus)*
USB (Universal Serial Bus) is an innovation in connecting your different desktop peripherals conveniently to your computer.
By using the USB, you will be able to connect your mouse, keyboard, and other to your monitor instead of having to
connect them to your computer. This will give you greater flexibility in setting up your system. USB allows you to connect
chain up to 120 devices on a single USB port, and you can "hot" plug (attach them while the computer is running) or unplug
them while maintaining Plug and Plug auto detection and configuration. This monitor has an integrated BUS-powered USB
hub, allowing up to 2 other USB devices to be attached it.



USB connection
1. Connect the upstream port of the Display to the downstream port of the USB compliant PC or another hub using the
USB cable. (Computer must have a USB port)
2. Connect the USB compliant peripherals to the downstream ports of the monitor.




This is a simplified representation
of rear view.




To USB downstream port
of the USB compliant PC or
another hub cable



USB downstream Port
connect the cables from USB
compliant peripherals-such as
keyboard, mouse, etc




NOTE
To activate the USB hub function, the monitor must be connected to a USB compliant PC(OS) or another hub with the USB
cable(enclosed).
When connecting the USB cable, check that the shape of the connector at the cable side matches the shape at the connecting
side.
Even if the monitor is in a power saving mode, USB compliant devices will function when they are connected the USB ports(both
the upstream and downstream) of the monitor.




-7-
WIRING DIAGRAM




Connector Ass'y P/N: 6631T25008Q




MAIN PCB


Connector Ass'y P/N:
6631T20015R

P902
MATAL FRAME J705
J801
J702
J710
Connector Ass'y P/N:
6631T20008U
CN3
CN2
CN1 CN7

CN6
CN5
CN4
CN_C02
CN_C01
CN301



MODULE




Connector Ass'y P/N: 6631T11012P




-8-
12V LCD Module

R,G,B




Inverte r CTL
Po we r CTL
Module CTL
differential LVDS:Low Voltage Differential Signaling

Micom Memory 3.3 VM
68HC08-BD48 LVDS (KM416S1 02B T)
Inverter (THC63LVD823)


M-CLK Address Data 48 Bit
Out - CLK
H/V-Sync DE ,H/V Sync out
12V 5V 5V 5V
R,G,B Even/Odd



Gm5020 2.5V 3.3V 3.3V
12V
including Reg. Reg. Reg.
(ADC / T MDS Rx )




-9-
H-Sy nc
5V
DVDD2.5V PVDD 3.3V DVDD 3.3V
AVD D2.5V 3.3 VM AVD D 3.3V




Power Board
H-Sync A Hsync
BLOCK DIAGRAM




V-Sync R,G,B
Switch
(A or B)
BA7657 Digital Signal
H-Sync B (Video Switch)

H-Sync B DVI-Analog Signal
H-Sync A
D-SUB R,G,B R,G,B DVI-I
V-Sync B
V-Sync A
DESCRIPTION OF BLOCK DIAGRAM

1. Input signal switching part(BA7657).
There are two anolog inputs which are D-Sub analog and DVI-anolog input.
They come from each 15 pin D-Sub and 29 pin DVI-I connector.

2. Video Controller Part(GM5020).
This part amplifies the level of video signal for the anolog to digital conversion and converts from the analog video
signal to the digital video signal using a pixelclock.
The pixel clock for each mode is generated by the PLL.
The range of the pixel clock is from 25MHz to 135MHz.
This part consists of the Scaler and frame buffers which converts frame rate of input signal to 60Hz frame rate.
The Scaler gets the video signal converted analog to digital, interpolates input to1280 X 1024 resolution signal and
outputs 8-bit R, G, B signal to transmitter.
Especially pre-amp / ADC / Video controller are merged to one chip `Gm5020' by Genesis.
Also FRC is separate.

3. Display Data Transmitter Part(LVDS).
This part transmit digital signal from the Scaler to the receiver of module.

4. Power Part.
This part consists of the one 5V, two 3.3V and one 2.5 regulators to convert power which is provided 12V, 5V in
Power Board.
12V is provided for inverter and LCD Panel, 5V is provided for Micom.
Also, 5V is converted 3.3V and 2.5V by regulator. Converted power is provided for IC in the main board.

5. MICOM Part.
This part consists of EEPROM IC which stores control data, Reset IC and the Micom.
The Micom distinguishes polarity and frequency of the H/V sync are supplied from signal cable.
The controlled data of each modes is stored in EEPROM.

6. Inverter
The inverter converts from DC12V to AC 700Vrms and operate back-light lamp of module.




- 10 -
12V
50 ~ 60Hz


HVDC 100KHz 5V
EMI INPUT RECTIFIER ENERGY OUTPUT RECTIFIER
COMPONENTS AND FILTER TRANSFER AND FILTER
LINE GND
100 ~ 240V




PWM CONTROL PHOTO-COUPLER SIGNAL
CIRCUIT ISOLATION COLLECTION




PRIMARY SECONDA RY




Operation description_Power
1. EMI components.
This part contains of EMI components to comply with global marketing EMI standards like FCC, VCCI CISPR,
the circuit included a line-filter, across line capacitor and of course the primary protection fuse.

2. Input rectifier and filter.
This part function is for transfer the input AC voltage to a DC voltage through a bridge rectifier and a bulk capacitor.

3. Energy Transfer.
This part function is transfer the primary energy to secondary through a power transformer.

4. Output rectifier and filter.
This part function is to make a pulse width modulation control and to provide the driver signal to power switch, to
adjust the duty cycle during different AC input and output loading condition to achive the dc output stablize, and also
the over power protection is also monitor by this part.

5. Photo-Coupler isolation.
This part function is to feed back the dc output changing status through a photo transistor to primary controller to
achive the stablized dc output voltage.

6. Signal collection.
This part function is to collect the any change from the dc output and feed back to the primary through photo
transistor




- 11 -
ADJUSTMENT
All adjustment are thoroughly checked and corrected 3. Adjustment for White Balance
when the monitor leaves the factory, but sometimes 1) Display color 0,0 pattern at Mode 15.
several minor adjustment may be required. 2) Set External Bright to MAX position and Contrast to
Adjustment should be following procedure and after MAX Position.
warming up for a minimum of 10 minutes. 3) Select PRESET START BIAS CAL command
and Enter.
· Alignment appliances and tools.
4) No attempt to manually adjust, BIAS data is auto-
- IBM compatible PC
matically adjusted and saved to the EEPROM.
- Programmable Signal Generator.
5) Display color 15,0 pattern at Mode 15.
(eg. VG-819 made by Astrodesign Co.)
6) Select DRIVE CAL command and Enter.
- E(E)PROM with each mode data saved.
7) 5800K and 9300K are automatically adjusted and
saved to the EEPROM.
1. Adjustment Start
8) Select PRESET EXIT command and Enter.
1) Display any pattern at any Mode.
2) Run alignment program for LB801H on the IBM
4. Adjustment for EDID
compatible PC.
1) Use this procedure only when there is some
3) Select EEPROM ALL INIT command and Enter
probelm on EDID data.
4) This will make all data to default state
2) Connect the D-sub cable.
5) Select COMMAND PRESET START command
3) Select EEPROM EDID Write command and
and Enter
Enter.
2. Adjustment for Factory Preset Mode 4) Select DDC(A) Write command and Enter.
1) Select DIST. ADJ FOS DEFAULT command 5) Connect the DVI-I cable.
and Enter 6) Select DDC(D) Write command and Enter.
2) It will copy all factory default data to EEPROM
automatically.




A

9 6
IBM 5 1
15 11
Video Signal Compatible PC 10 6
Generator 5 1
C

PARALLEL PORT 13 1
d
se




25 14
tu


2C
No




OFF ON
23




5V
RS




F
L
Control Line




E
LL




C
RA
PA




5V
Power inlet (required) 4.7K
220
ON 5V 4.7K
Power Select Switch
E
ER




VG
W




S 74LS06
(110V/220V)
PO




OFF 4.7K
A
ST




MO Power LED
C




NI
YN




TO
74LS06
V-S




R



E ST Switch
B B

F V-Sync On/Off Switch
(Switch must be ON.)

Figure 1. Cable Connection


- 12 -
TROUBLESHOOTING GUIDE
1. NO POWER


NO POWER
(POWER INDICATOR OFF)




CHECK J801 NO TROUBLE IN
INPUT VOLTAGE
BULT-IN POWER
(12V) ?



YES




CHECK J801 NO TROUBLE IN
5VST VOLTAGE
BULT-IN POWER
(5V) ?



YES



CHECK
U501's PIN 6. NO TROUBLE IN
IS THIS PIN
U501 or X501
OSCILLATED?



YES




TROUBLE
SOMEWHERE ELSE




- 13 -
2. NO RASTER


NO RASTER




CHECK NO TROUBLE IN
J702 PIN 1, 2, 3
POWER ADATER
(12V) ?
or L703, L704
YES


CHECK NO TROUBLE IN
J702 PIN 8 (5V) ? INVON PATTERN


YES


CHECK
NO TROUBLE IN
X501
X501
H. PULSE ?

YES


CHECK NO TROUBLE IN
U201(GM5020) ?
U201

YES


CHECK
NO TROUBLE IN
L201, L202, L203
PULSE? U201

YES


CHECK
U301, U302, U303 NO TROUBLE IN
PIN 35 U201
MEMORYCLK?




- 14 -
YES


CHECK
L204 NO TROUBLE IN
PULSE ? U201


YES



CHECK
NO CHECK DOT CLOCK
U401 PIN 10
PULSE ? PATTERN



YES


CHECK
U401 PIN 8 NO CHECK
V.PULSE? DVS PATTERN


YES



CHECK NO
U401 PIN 7 CHECK
V.PULSE? DHS PATTERN


YES




TROUBLE IN
LCD MODULE




- 15 -
3. NO CLOCK (CLOCK GENERATOR)



NO DOT CLOCK


YES


CHECK
NO TROUBLE IN
X201 24MHz ?
X201


YES


CHECK
NO TROUBLE IN
L201
CLOCK ? U201




- 16 -
4. TROUBLE IN DPM


TROUBLE IN DPM




CHECK NO CHECK PC
R233, R234? PC IS NOT GOING
INTO DPM OFF MODE


YES



CHECK
U501 PIN 6 NO TROUBLE IN
WAVEFORM X501
(24MHz) ?


YES



CHECK NO TROUBLE IN
U501 PIN 11
SIGNAL CABLE
(0V) ?


YES




TROUBLE IN PC




- 17 -
PRINTED CIRCUIT BOARD

1. MAIN BOARD (Component Side)



L820




L810




R807
1
J705
J801 U802
L821 C817
J702
C845 C850
L811 R809

C531 C844
R810
C701 U503
C526
C409
C840




R745 R581
C707




C834


R582
C516 U821
R702




C517
R746




R406
U401




60
70
RA212
R701 R514 R543
L402
R545
R515
R520

R517




50
C706




CA211
R542 R544
C410




80
RA210




CA210
C521




40
RA208 RA206




90
CA209
C522




30
CA208




100
RA204




U501 C413 C408




20
1




10
CA207
RA202




R236
C501 R501 C502
R502 CA206
C503




J706




1
R508



R510




CA205 CA204 CA203 CA212 CA202




L403