LG 782LS User Manual

COLOR MONIT OR
SER VICE MANUAL
Website:http://biz.LGservice.com
E-mail:http://www.LGEservice.com/techsup.html
CAUTION
BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
MODEL: LCD 782LS (LB782G-GD)
*( ) ID LABEL MODEL No.
CONTENTS
- 2 -
SPECIFICATIONS ................................................... 2
PRECAUTIONS ....................................................... 3
TIMING CHART ....................................................... 4
OPERATING INSTRUCTIONS ................................ 5
WIRING DIAGRAM ................................................. 6
DISASSEMBLY ....................................................... 7
BLOCK DIAGRAM AND DESCRIPTION ................ 8
ADJUSTMENT ....................................................... 11
TROUBLESHOOTING GUIDE .............................. 12
PRINTED CIRCUIT BOARD................................... 17
EXPLODED VIEW...................................................19
REPLACEMENT PARTS LIST ...............................21
PIN CONFIGURATION............................................25
SCHEMATIC DIAGRAM......................................... 26
SPECIFICATIONS
1. LCD CHARACTERISTICS
Type : TFT Color LCD Module Size : 17.0 inch (43.2 cm diagonal) Pixel Pitch : 0.264(H) x 0.264(V) Elecctrical Interface : LVDS Color Depth : 6-bits+FRC, 16,194,277 colors Size (mm) : 383.5(H) x 306(V) x 21.0(D) Typ Surface Treatment : Anti-Glare, Hard Coating (3H) Operating Mode : Normally white Backlight Unit : Four-CCFL (Cold Cathode
Fluorescent Lamp)
2. OPTICAL CHARACTERISTICS
2-1. Viewing Angle by Contrast Ratio
10
Left : 70° Typ. , Right : -70° Typ. Top : 45° Typ. , Bottom : -65° Typ.
2-2. Luminance : 200 (min.) 250 (typ.)
2-3. Contrast Ratio : 250 (min) 400 (typ.)
3. SIGNAL (Refer to the Timing Chart)
3-1. Sync Signal
• Type : Separate TTL (Positive/Negative)
3-2. Video Input Signal
1) Type : R, G, B Analog
2) Voltage Level : 0~0.714 V a) Color 0, 0 : 0 Vp-p b) Color 7, 0 : 0.467 Vp-p c) Color 15, 0 : 0.714 Vp-p
3) Input Impedance : 75
3-3. Operating Frequency
Horizontal : 30 ~ 83 kHz Vertical : 56 ~ 75 Hz
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 : 5% ~ 95%
(Non-condensing)
6. DIMENSIONS (with TILT/SWIVEL)
Width : 419 mm (16.49'') Depth : 205 mm (8.07'') Height : 410 mm (16.14'')
7. WEIGHT (with TILT/SWIVEL)
Net. Weight : 6.8 kg (14.99 lbs) Gross Weight : 8.4 kg (18.52 lbs)
MODE
POWER ON (NORMAL)
STAND-BY
SUSPEND
OFF
POWER OFF
H/V SYNC
ON/ON OFF/ON ON/OFF
OFF/OFF
-
POWER CONSUMPTION
less than 45 W
less than 3 W less than 3 W
less than 3 W less than 3 W
LED COLOR
GREEN AMBER AMBER AMBER
OFF
VIDEO
ACTIVE
OFF OFF OFF
-
- 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.
TIMING CHART
- 4 -
VIDEO
SYNC
B
D
C
F
E
A
H + 31.469 800 640 16 96 48 V 70.09 449 350 37 2 60
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 + 37.879 1056 800 40 128 88 V + 60.317 628 600 1 4 23 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 1125 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
640x480
60Hz
640x480
75Hz
720x400
70Hz
800x600
60Hz
800x600
75Hz
832x624
75Hz
1024x768
60Hz
1024x768
75Hz
1152x870
75Hz
1152x900
65Hz
1280x1024
60Hz
1280x1024
75Hz
<< Dot Clock (MHz), Horizontal Frequency (kHz), Vertical Frequency (Hz), Horizontal etc... (µs), Vertical etc... (ms) >>
Sync
Polarity
Frequency
DOT
Clock
Total Period
(E)
Video Active
Time (A)
Sync Duration
(D)
Back Porch
(F)
Front Porch
(C)
Resolution
- 5 -
1. MENU Button
Use this button to enter or exit the on screen display.
2.
Use these buttons to choose or adjust items in the on screen display
3.
AUTO Button
Use this button to enter a selection in the on screen display.
4.
OPERATING INSTRUCTIONS
Front Control Panel
FRONT VIEW REAR VIEW
D
AUDIO DC OUT
D-Sub Signal Port
Power Connector
AUDIO DC OUT
Power (DPMS) Indicator
Power ON/OFF Button
Button
AUTO Button
Power Button
MENU Button
Power Indicator
SET Button
Button
<Shortcut Keys>
Brightness and Contrast can be adjusted directly without entering the On Screen Display (OSD) system. Touch the buttons to adjust the settings and then the OSD button to save all changes. The Brightness and Contrast functions are also available in the On Screen Display (OSD) menu.
100
100
* AUTO adjustment function
TO the AUTO button before using OSD menu. This button is for the automatic adjustment of the screen position, clock and phase. Note: Some signal from some graphics boards may not function properly. If the results are unsatisfactory, adjust your monitors Position, Clock and Phase manually.
PROCESSING
AUTO CONFIGURATION
MENU, Button
CONTROLS LOCKED
CONTROLS UNLOCKED
Press the hold the MENU button and
button for 3 seconds: the message
CONTROLS LOCKED appears.
You can unlock the OSD controls
at any time by pushing the MENU,
button for 3 seconds:
the message CONTROLS UNLOCKED will appear.
- 6 -
WIRING DIAGRAM
J801
PG4
J702
CN1
CN3
J1
CN2
Connector Ass’y P/No.: 6631T11012W
Connector Ass’y P/No.:
6631T25008R
Connector Ass’y P/No.:
6631T20015A
Connector Ass’y P/No.:
6631T20008P
J706
J710
- 7 -
DISASSEMBLY
(a)
(a)
(a)
(a)
1) Set the Monitor face downward.
2) Remove four screws (a).
BACK COVER REMOVAL
3) Set the Monitor as picture.
4) Release the bottom & side latch.
7) Release the center positon latch.
5) Set the Monitor face upward.
6) Release the up side latch.
8) Set the Monitor face downward.
9) Remove the Back cover.
Caution: When you open the Back cover, Be careful! Dont stress the Control Board Connector.
(b) Latch Point
(b)
(b)
(b)
(b)
(b)
(b)
(b)
(b)
(b)
(b)
BLOCK DIAGRAM
- 8 -
To
Inverter
12V
BRT-CTL
Tx+/-,Hs,Vs,CLK,DEN
INV-CTL
EEPROM
(SYSTEM)
Analog
Signal
ADC
+ PLL
OSD
Scaling
GM5020
DC/DC Block
Regulator
Regulator
2.5V
3.3V
MCU
L VDS Tx
POWER BOARD
DDC
(EDID)
12V(Inverter)
5.0V
90-264V
12V
Module Power (5V)
DSUB
(H/V Sync)
(R,G,B)
SDA, SCL
H SYNC
AC INPUT
DESCRIPTION OF BLOCK DIAGRAM
- 9 -
1. Input signal part.
There is one input which is analog. It comes from 15 pin D-Sub connector.
2. Pre-amp/ ADC / PLL / Video Controller.
This part amplifies the level of video signal from the analog video signal to the digital video signal using a pixel clock. The pixel clock for each mode is generated by the PLL. The range of the pixel clock is from 25MHz to 135.0MHz. The Scaler gets the video signal converted analog to digital, interpolates input to 1280 X 1024 resolution signal and outputs 8-bit R, G, B signal to LCD module. Especially pre-amp / ADC / Video controller are merged to one chip gm5020 by Genesis.
3. Power Part.
This circuit is working of 90~260VAC(50/60Hz). The operation procedure is as follows:
1) AC Input voltage is rectified and smoothed by the bridge diodes(BD901) and the capacitor(C905).
2) The Rectified voltage(DC) is applied to the primary coil of the transformer(T901).
3) The control IC(IC901) generates switching pulse to turn on and turn off the primary coil of the transformer(T901).
4) Depending on turn ratio of the transformer, the secondary voltages appear at the secondary coils of the transformer(T901).
5) These secondary voltages(12V,5V) are rectified by each diodes(D903,D906) and operates other circuit.(Inverter,Scaleretc)
4. 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.
5. Inverter
The inverter converts from DC12V to AC 700V and operate back-light lamp of module.
BLOCK DIAGRAM
- 10 -
EMI
COMPONENTS
LINE
100 ~ 240V
INPUT RECTIFIE R
AND FILTER
ENERGY
TRANSFER
OUTPUT RECTIFIE R
AND FILTER
12V
5V
GND
SIGNAL
COLLENTION
PHOTO-COUPLER
ISOLATION
PWM CONTROL
CIRCUIT
HVDC
100KHz
PRIMARY
SECONDARY
50 ~ 60Hz
POWER BOARD
DESCRIPTION OF BLOCK DIAGRAM
1. EMI components.
This part contains of EMI components to comply with global marketing EMI standards like FCC 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
Loading...
+ 23 hidden pages