LG 808K User manual

AUTO SOURCE/SETOSD
COLOR MONITOR
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS NO. : CL-42
FACTORY MODEL: LG808K
MODEL: FPD1830

1. LCD CHARACTERISTICS
Type : TFT Color LCD Module
Size : 18.1inch(45.974cm diagonal)
Pixel Pitch : 0.2805(H) x 0.2805(V)
Color Depth : 8-bit, 16,777,216 colors
Electrical Interface : LVDS
Surface Treatment : Anti-Glare, Hard Coating(3H)
Operating Mode : Normally Black
Backlight Unit : Six-CCFL (Cold Cathode
Fluorescent Lamp)
2. OPTICAL CHARACTERISTICS
2-1. Viewing Angle by Contrast Ratio
≥ 10
Left : -60° min., -80°(Typ)
Right : +60° min., +80°(Typ)
Top : +60° min., +80°(Typ)
Bottom : -60° min., -80°(Typ)
2-2. Luminance : 200(min), 250(Typ)
2-3. Contrast Ratio : 200(min), 350(Typ)
3. SIGNAL (Refer to the Timing Chart)
3-1. Sync Signal
Type : Separate Sync, Digital
3-2. Video Input Signal
1) Type : R, G, B Analog
2) Voltage Level : 0~0.70 V
a) Black : 0.0 Vp-p
b) 128 Gray : 0.35 Vp-p
c) Full White : 0.70 Vp-p
3) Input Impedance : 75 Ω
3-3. Operating Frequency
Horizontal : 30 ~ 83 kHz
Vertical : 56 ~ 75 Hz
4. MAX. RESOLUTION
Analog : 1280 x 1024@75Hz
Digital : 1280 x 1024@75Hz
4. POWER SUPPLY
4-1. Power
AC 100~240V, 50/60Hz , 1.0A
4-2. Power Consumption
5. ENVIRONMENT
5-1. Operating Temperature: 10°C~35°C (50°F~95°F)
(Ambient)
5-2. Relative Humidity : 10%~80%
(Non-condensing)
5-3. MTBF : 50,000 Hours(Min)
6. DIMENSIONS (with TILT/SWIVEL)
Width : 422 mm (16.61'')
Depth : 205 mm (8.07'')
Height : 424 mm (16.69'')
7. WEIGHT (with TILT/SWIVEL)
Net. Weight : 7.5kg (16.54 lbs)
Gross Weight : 9.3kg (20.50 lbs)
CONTENTS
SPECIFICATIONS
- 2 -
SPECIFICATIONS ................................................... 2
PRECAUTIONS ....................................................... 3
TIMING CHART ....................................................... 4
OPERATING INSTRUCTIONS ................................ 5
WIRING DIAGRAM ................................................. 6
BLOCK DIAGRAM ................................................... 7
DESCRIPTION OF BLOCK DIAGRAM.....................8
ADJUSTMENT ...................................................... 10
TROUBLESHOOTING GUIDE .............................. 11
PRINTED CIRCUIT BOARD................................... 16
EXPLODED VIEW...................................................19
REPLACEMENT PARTS LIST ...............................21
SCHEMATIC DIAGRAM......................................... 25
MODE
POWER ON (NORMAL)
STAND-BY
SUSPEND
DPM OFF
H/V SYNC
ON/ON
OFF/ON
ON/OFF
OFF/OFF
POWER CONSUMPTION
less than 55 W
LED COLOR
GREEN
AMBER
VIDEO
ACTIVE
OFF
OFF
OFF
less than 2 W
(at 115V/60Hz)

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

- 4 -
TIMING CHART
VIDEO
SYNC
B
D
CFE
A
<< Dot Clock (MHz), Horizontal Frequency (kHz), Vertical Frequency (Hz), Horizontal etc... (µs), Vertical etc... (ms) >>
H + 31.469 800 640 16 96 48
V–70.09 449 350 37 2 60
H + 37.879 1056 800 40 128 88
V + 60.317 628 600 1 4 23
H–31.469 800 640 16 96 48
V–59.94 525 480 10 2 33
H–37.5 840 640 16 64 120
V–75 500 480 1 3 16
H–31.468 900 720 18 108 54
V + 70.08 449 400 12 2 35
H + 46.875 1056 800 16 80 160
V + 75.0 625 600 1 3 21
H+/–49.725 1152 832 32 64 224
V+/–74.55 667 624 1 3 39
H–48.363 1344 1024 24 136 160
V–60.0 806 768 3 6 29
H–60.123 1312 1024 16 96 176
V–75.029 800 768 1 3 28
H+/–68.681 1456 1152 32 128 144
V+/–75.062 915 870 3 3 39
H+/–61.805 1504 1152 18 134 200
V+/–65.96 937 900 2 4 31
H + 63.981 1688 1280 48 112 248
V + 60.02 1066 1024 1 3 38
H + 79.976 1688 1280 16 144 248
V + 75.035 1066 1024 1 3 38
Mode H/V
Sort
1
2
3
4
5
6
7
8
9
10
11
12
13
25.175
28.321
25.175
31.5
40.0
49.5
57.283
65.0
78.75
100.0
92.978
108.0
135.0
640x350
70Hz
800x600
60Hz
640x480
60Hz
640x480
75Hz
720x400
70Hz
800x600
75Hz
832x624
75Hz
1024x768
60Hz
1024x768
75Hz
1152x900
75Hz
1152x900
65Hz
1280x1024
60Hz
1280x1024
75Hz
Sync
Polarity Frequency
Dot
Clock Total Period
(E)
Video Active Time
(A)
Sync Duration
(D)
Back Porch
(F)
Front Porch
(C)
Resolution

- 5 -
OPERATING INSTRUCTIONS
FRONT VIEW REAR VIEW
Front Control Panel
1. Power ON/OFF Button
Use this button to turn the monitor on or off.
2. Power Indicator
This indicator lights up green when the monitor
operates normally; in DPMS (Energy Saving)
mode, -stand-by, suspend, or power off mode -its
color changes to amber.
3. Button
Use these buttons to choose or adjust items in the on screen
display.
4. SOURCE/SET Button
Use this button to make Dsub or DVI connector active.
This feature is used when two computers are connected to
the monitor. The default setting is Dsub.
Use this button to enter a selection in the on screen display.
5. OSD Button
Use this button to enter or exit the on screen display.
AUTO SOURCE/SETOSD
Buttons
OSD Button SOURCE/SET Button
Power Button
Power Indicator
D-Sub Signal
Connector
Power Connecter
DVI-D Signal
Connector
AUTO SOURCE/SETOSD
1
54
3
2

CN4
CN3
CN6CN5
CN1
CN7
CN2
J702
J710
J1
J801
P902
P705
- 6 -
WIRING DIAGRAM
Connector Ass’y P/N: 6631T20015G
Connector Ass’y P/N: 6631T11016D
Connector Ass’y P/N:
6631T20015B
Connector Ass’y P/N:
6631T25008Q

- 7 -
BLOCK DIAGRAM

- 8 -
DESCRIPTION OF BLOCK DIAGRAM
1. Input signal switching part.
There are two inputs which are analog and digital input.
They come from each 15 pin D-Sub and 24 pin DVI-D connector.
2. Video Controller Part.
This part amplifies the level of video signal for the 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, Flash-ROM IC which stores program data,Reset IC.
The Scaler gets the video signal converted analog to digital, interpolates input to1280 X 1024 resolution signal and
outputs R, G, B signal to transmitter.
The controlled data of each modes and user setting is stored in EEPROM
Especially Micom/pre-amp / ADC / Video controller are merged to one chip ‘Gm5120’by Genesis. .
3. Display Data Transmitter Part.
This part transmit digital signal from the Scaler to the receiver of module.
4. Power Part.
This part consists of the one 5V, one 3.3V and one 2.5 regulators to convert power which is provided 12V, 5V in
Power Board.
12V is provided for LCD Panel.
Also, 5V is converted 3.3V and 2.5V by regulator. Converted power is provided for IC in the main board.

- 9 -
EMI
COMPONENTS
LINE
100 ~ 240V
INPUT RECTIFIER
AND FILTER ENERGY TRANSFER OUTPUT RECTIFIER AND FILTER
12V
5V
GND
SIGNAL
COLLECTION
PHOTO-COUPLER
ISOLATION
PWM CONTROL
CIRCUIT
HVDC 100KHz
PRIMARY SECONDARY
50 ~ 60Hz
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
POWER BOARD

- 10 -
ADJUSTMENT
All adjustment are thoroughly checked and corrected
when the monitor leaves the factory, but sometimes
several minor adjustment may be required.
Adjustment should be following procedure and after
warming up for a minimum of 10 minutes.
•Alignment appliances and tools.
- IBM compatible PC
- Programmable Signal Generator.
(eg. VG-819 made by Astrodesign Co.)
- E(E)PROM with each mode data saved.
1. Adjustment Start
1) Display any pattern at any Mode.
2) Run alignment program for LG808K on the IBM
compatible PC.
3) Select INIT →Initialize command and Enter
4) This will make all data to default state
5) Select COLOR →PRESET START command
and Enter
2. Adjustment for Factory Preset Mode
1) Select DIST. ADJ →FOS DEFAULT command
and Enter
2) It will copy all factory default data to EEPROM
automatically.
3. Adjustment for White Balance
1) Display color 0,0 pattern at Mode 13.
2) Select COLOR → BIAS CALIBRATION command
and Enter.
3) No attempt to manually adjust, BIAS data is auto-
matically adjusted and saved to the EEPROM.
4) Display color 15,0 pattern at Mode 13.
5) Select GAIN CALIBRATION command and Enter.
6) 6500K and 9300K are automatically adjusted and
saved to the EEPROM.
7) Select COLOR → PRESET END command and
Enter.
4. Adjustment for EDID
1) Use this procedure only when there is some
probelm on EDID data.
2) Connect the D-sub cable.
3) Select EDID →Write EDID[A0] command and
Enter.
4) Select DDC(A) Write command and Enter.
5) Connect the DVI-I cable.
6) Select DDC(D) Write command and Enter.
Figure 1. Cable Connection
220
IBM
Compatible PC
PARALLEL PORT
Power inlet (required)
Video
Signal
Generator
Power LED
ST Switch
Power Select Switch
(110V/220V)
Control Line
Not used
RS232C
PARALLEL
V-SYNC POWER
ST
VGS MONITOR
E
E
V-Sync On/Off Switch
(Switch must be ON.)
F
F
A
A
B
B
C
C
1510
5
569
1
1
1
14
13
25
6
5V
5V
5V
4.7K
4.7K
4.7K
74LS06
74LS06
OFF ON
OFF
ON
11

- 11 -
TROUBLESHOOTING GUIDE
1. NO POWER
TROUBLE IN
POWER
CHECK J703
5V VOLTAGE
(5V) ?
NO
NO POWER
(POWER INDICATOR OFF)
TROUBLE
SOMEWHERE ELSE
TROUBLE IN
POWER
CHECK J703
INPUT VOLTAGE
(12V) ?
NO
TROUBLE IN
U203 or X201
NO
YES
YES
YES
CHECK
U203’s PIN 151.
IS THIS PIN
OSCILLATED?

- 12 -
2. NO RASTER
TROUBLE IN
POWER
CHECK
J703 PIN 5, 6
(5V) ?
NO
NO RASTER
TROUBLE IN
POWER
CHECK
J703 PIN 1, 2
(12V) ?
NO
TROUBLE IN
U801
CHECK
U801
(3.3V)?
NO
TROUBLE IN
U201
CHECK
U201 ? NO
TROUBLE IN
U203
NO
YES
YES
YES
YES
CHECK
R234, R235, R237
PULSE?

- 13 -
CHECK DOT CLOCK
PATTERN
NO
CHECK
DVS PATTERN
NO
CHECK
DHS PATTERN
NO
YES
YES
YES
YES
TROUBLE IN
LCD MODULE
CHECK
U401 PIN 8
V.PULSE?
CHECK
U401 PIN 7
H.PULSE?
CHECK
U401 PIN 10
PULSE ?

- 14 -
3. NO CLOCK (CLOCK GENERATOR)
NO DOT CLOCK
TROUBLE IN
X201
CHECK
X201 20MHz ? NO
TROUBLE IN
U203
CHECK
R237
CLOCK ?
NO
YES
YES

- 15 -
4. TROUBLE IN DPM
TROUBLE IN DPM
TROUBLE IN PC
CHECK PC
PC IS NOT GOING
INTO DPM OFF MODE
NO
TROUBLE IN
X201
NO
TROUBLE IN
SIGNAL CABLE
NO
YES
YES
YES
CHECK
U203 PIN 152
WAVEFORM
(20MHz) ?
CHECK
R713, R716?
CHECK
U203 PIN 49
?

PRINTED CIRCUIT BOARD
- 16 -
1. MAIN BOARD (Component Side)
30
J710
1
C734 C733 C732 C731 C730 C729
C801
R202
5
R249
Q701
R740
R741
B
1
R715
J706
C413
20
R401 R402
C401
R407
1
10
R745
R404 R405
R403
U803
R748 R742R747
B
R743 R744
C802 R286
R266
R265
R284
R285
R267
10
25
R782
R777
R248
R776
Q702
R783
R779
R778
R786
Q704
R716
R787
C736
R714
ZD707
ZD706
1
30
90100
R260 R276 R272 R214 R208 R210
R802
A
R288
R287
R706
15
20
R277
U201
R253
R201
R251
Q202
U207
R784
Q703
R713
R785
C735
D703 D704
1
40 50
80
R250 R217 R216 R215 R207 R209 R211
R275
R206
C806
C807
R205
Q201
A
R264
R752
R252
C232
R753
ZD710
U703
D701 D702
C819
C817
L823
60 70
U401
1
C207
U205
40 50
20 30
10
R243 R242
1
R292 R244
R241
R240
R247
R246
C740
C714
ZD704
R712
R711
C715
ZD703
J704
L830
R408
R406
RA210
RA211
RA209
60
R290
200
R278
R291
R228
R227
C280
C211
R734
R733
C703
U702
1
C408
C860
R409
RA208RA206
RA207
U203
70 80
180 190
R223
R224
R226
R225
C282
C281
C204
C210
R718
ZD711
R719
D739 D738
R809
C845
J703
U802
C410
R814
R813
U801
MODEL:LG808K P/N :6870T573A11 DATE :2002.10.10
RA204
RA205RA203
90
170
R775
R774
R773
R772
R771
R770
D737
D735
D736D734
L811
C840
C818
R810
R819
R812
R811
R818
R817
R801
RA202RA200
RA201
100
110 120 130 140 150
160
R268
C202
C739
C702
U701
D733
ZD701
D732
R830
1
J702 C706
C811 C808
R820
R816
R815
C809
R800
C810
R289 R220 R219
R233
R232
R231
R230
R229 R221
C201
U704
C738
C737
R788
ZD702
1
ZD705
C812 C813
C285
R299 R298
R297 R281
R280
X201
J708

- 17 -
2. MAIN BOARD (Solder Side)
R259
C203
R257
R258
R256
R255
R254
C402
C404
R705
R704
R703
C403
C406
R274
C205
C407
C405
R203
R204
R273C206
R218
C214
C245
C247
C244 C246
D709
C215
C227
R239
C235
C234
D710
C209
R234
C217
C218
C219
C228
C229
C237
C236
C238
R729
D723
D724
C212
C213
R236
R235
R237
C230
C284
C283 R282
C241
C240
C239
C727
D722
D721
C221
C216
C222
C220
R283
C224
C225
C223
C226
C233
C242
C728
R732
R726 R727
D718
D720
D717 D719
C231
R702
D711

- 18 -
3. POWER B OARD (Component Side)
4. POWER B OARD (Solder Side)

- 19 -
EXPLODED VIEW
1
5
8
14
13
11
6
9
12
4
3
b
a
7
10
2

- 20 -
EXPLODED VIEW PARTS LIST
Ref. No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
a
b
Part No.
3091TKL052C
6304FLP034A
3809TKL033B
3043TKK078L
4814TKK230B
4951TKS093E
6633TZA015A
6871TPT230A
3313TL8026A
6631T11016D
6871TST352A
3846TKK053A
6866TDV004J
6850TD9001G
1SZZTER001H
332-113S
Description
CABINET ASSEMBLY, LG808H G/WAY 3090TKL052 (CKD)
LCD(LIQUID CRYSTAL DISPLAY) LM181E06-A4M1 LG PHILPS TFT COLOR SXGA 18.1"
BACK COVER ASSEMBLY, LG808H 3808TKL038 MX
TILT SWIVEL ASSEMBLYLG883D . BK, MX(LOCAL), HINGE, COVER(CKD)
SHIELD INVERTER SHIELD LG808K-SKD
METAL ASSEMBLY, FRAME LG808K(CKD)
INVERTER ASSEMBLY, AMBIT K11I010.00 6 LAMPS FOR LG808H
PWB(PCB) ASSEMBLY, POWER, LG808H POWER TOTAL G/WAY
MAIN TOTAL ASSEMBLY LG808K G/WAY CL-42
CONNECTOR ASSEMBLY, 30P H-H 200MM UL20276 18" STD LG808H
PWB(PCB) ASSEMBLY, SUB, LG708K & LG808K CONTROL TOTAL G/WAY
MARK, PIECE G/WAY LOGO STICKER
CABLE, DVI, UL20276 DT 2000MM BLACK(9930) LG883D DM
CABLE,D-SUB, UL 2990-9C(7.5) DT 1870MM BLACK(9930) , DM
SCREW,DRAWING, D3.0 L10.0 MSWR/BK
SCREW,DRAWING, D3.0 L12.0 MSWR/BK
* Note: Safety mark