LG Electronics 20LS7D(C)-UB User manual
- Category
- TVs & monitors
- Type
- User manual
LCD TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : LA74E
MODEL : 20LS7D(C) 20LS7D(C)-UB
website:http://biz.LGservice.com
- 2 -
CONTENTS
CONTENTS .............................................................................................. 2
PRODUCT SAFETY ..................................................................................3
SPECIFICATION ........................................................................................6
ADJUSTMENT INSTRUCTION ...............................................................10
TROUBLE SHOOTING ............................................................................14
BLOCK DIAGRAM...................................................................................19
EXPLODED VIEW ...................................................................................20
REPLACEMENT PARTS LIST ............................................................... 22
SVC. SHEET ...............................................................................................
- 3 -
SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the
Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent
Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance
An isolation Transformer should always be used during the
servicing of a receiver whose chassis is not isolated from the AC
power line. Use a transformer of adequate power rating as this
protects the technician from accidents resulting in personal injury
from electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
When replacing a high wattage resistor (Oxide Metal Film Resistor,
over 1W), keep the resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Before returning the receiver to the customer,
always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc., to
be sure the set is safe to operate without damage of electrical
shock.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source, connect an
electrical jumper across the two AC plug prongs. Place the AC
switch in the on position, connect one lead of ohm-meter to the AC
plug prongs tied together and touch other ohm-meter lead in turn to
each exposed metallic parts such as antenna terminals, phone
jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter
with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC voltage
measurements for each exposed metallic part. Any voltage
measured must not exceed 0.75 volt RMS which is corresponds to
0.5mA.
In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
1.5 Kohm/10W
To Instrument’s
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
IMPORTANT SAFETY NOTICE
0.15uF
- 4 -
CAUTION: Before servicing receivers covered by this service
manual and its supplements and addenda, read and follow the
SAFETY PRECAUTIONS on page 3 of this publication.
NOTE: If unforeseen circumstances create conflict between the
following servicing precautions and any of the safety precautions on
page 3 of this publication, always follow the safety precautions.
Remember: Safety First.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power
source before;
a. Removing or reinstalling any component, circuit board
module or any other receiver assembly.
b. Disconnecting or reconnecting any receiver electrical plug or
other electrical connection.
c. Connecting a test substitute in parallel with an electrolytic
capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity
installation of electrolytic capacitors may result in an
explosion hazard.
2. Test high voltage only by measuring it with an appropriate high
voltage meter or other voltage measuring device (DVM,
FETVOM, etc) equipped with a suitable high voltage probe.
Do not test high voltage by "drawing an arc".
3. Do not spray chemicals on or near this receiver or any of its
assemblies.
4. Unless specified otherwise in this service manual, clean
electrical contacts only by applying the following mixture to the
contacts with a pipe cleaner, cotton-tipped stick or comparable
non-abrasive applicator; 10% (by volume) Acetone and 90% (by
volume) isopropyl alcohol (90%-99% strength)
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of
contacts in not required.
5. Do not defeat any plug/socket B+ voltage interlocks with which
receivers covered by this service manual might be equipped.
6. Do not apply AC power to this instrument and/or any of its
electrical assemblies unless all solid-state device heat sinks are
correctly installed.
7. Always connect the test receiver ground lead to the receiver
chassis ground before connecting the test receiver positive
lead.
Always remove the test receiver ground lead last.
8. Use with this receiver only the test fixtures specified in this
service manual.
CAUTION: Do not connect the test fixture ground strap to any
heat sink in this receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged easily
by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some field-effect transistors and
semiconductor "chip" components. The following techniques
should be used to help reduce the incidence of component
damage caused by static by static electricity.
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any electrostatic
charge on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to
prevent potential shock reasons prior to applying power to the
unit under test.
2. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such as
aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an anti-static type solder removal device. Some solder
removal devices not classified as "anti-static" can generate
electrical charges sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it.
(Most replacement ES devices are packaged with leads
electrically shorted together by conductive foam, aluminum foil
or comparable conductive material).
7. Immediately before removing the protective material from the
leads of a replacement ES device, 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 bodily motions when handling unpackaged
replacement ES devices. (Otherwise harmless motion such as
the brushing together of your clothes fabric or the lifting of your
foot from a carpeted floor can generate static electricity
sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded-tip, low-wattage soldering iron and appropriate
tip size and shape that will maintain tip temperature within the
range or 500°F to 600°F.
2. Use an appropriate gauge of RMA resin-core solder composed
of 60 parts tin/40 parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire-
bristle (0.5 inch, or 1.25cm) brush with a metal handle.
Do not use freon-propelled spray-on cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.
(500°F to 600°F)
b. Heat the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-
type solder removal device or with solder braid.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
6. Use the following soldering technique.
a. Allow the soldering iron tip to reach a normal temperature
(500°F to 600°F)
b. First, hold the soldering iron tip and solder the strand against
the component lead until the solder melts.
c. Quickly move the soldering iron tip to the junction of the
component lead and the printed circuit foil, and hold it there
only until the solder flows onto and around both the
component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
d. Closely inspect the solder area and remove any excess or
splashed solder with a small wire-bristle brush.
SERVICING PRECAUTIONS
- 5 -
IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through
which the IC leads are inserted and then bent flat against the
circuit foil. When holes are the slotted type, the following technique
should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique
as outlined in paragraphs 5 and 6 above.
Removal
1. Desolder and straighten each IC lead in one operation by gently
prying up on the lead with the soldering iron tip as the solder
melts.
2. Draw away the melted solder with an anti-static suction-type
solder removal device (or with solder braid) before removing the
IC.
Replacement
1. Carefully insert the replacement IC in the circuit board.
2. Carefully bend each IC lead against the circuit foil pad and
solder it.
3. Clean the soldered areas with a small wire-bristle brush.
(It is not necessary to reapply acrylic coating to the areas).
"Small-Signal" Discrete Transistor
Removal/Replacement
1. Remove the defective transistor by clipping its leads as close as
possible to the component body.
2. Bend into a "U" shape the end of each of three leads remaining
on the circuit board.
3. Bend into a "U" shape the replacement transistor leads.
4. Connect the replacement transistor leads to the corresponding
leads extending from the circuit board and crimp the "U" with
long nose pliers to insure metal to metal contact then solder
each connection.
Power Output, Transistor Device
Removal/Replacement
1. Heat and remove all solder from around the transistor leads.
2. Remove the heat sink mounting screw (if so equipped).
3. Carefully remove the transistor from the heat sink of the circuit
board.
4. Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.
6. Replace heat sink.
Diode Removal/Replacement
1. Remove defective diode by clipping its leads as close as
possible to diode body.
2. Bend the two remaining leads perpendicular y to the circuit
board.
3. Observing diode polarity, wrap each lead of the new diode
around the corresponding lead on the circuit board.
4. Securely crimp each connection and solder it.
5. Inspect (on the circuit board copper side) the solder joints of
the two "original" leads. If they are not shiny, reheat them and if
necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1. Clip each fuse or resistor lead at top of the circuit board hollow
stake.
2. Securely crimp the leads of replacement component around
notch at stake top.
3. Solder the connections.
CAUTION: Maintain original spacing between the replaced
component and adjacent components and the circuit board to
prevent excessive component temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit
board will weaken the adhesive that bonds the foil to the circuit
board causing the foil to separate from or "lift-off" the board. The
following guidelines and procedures should be followed whenever
this condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the
following procedure to install a jumper wire on the copper pattern
side of the circuit board. (Use this technique only on IC
connections).
1. Carefully remove the damaged copper pattern with a sharp
knife. (Remove only as much copper as absolutely necessary).
2. carefully scratch away the solder resist and acrylic coating (if
used) from the end of the remaining copper pattern.
3. Bend a small "U" in one end of a small gauge jumper wire and
carefully crimp it around the IC pin. Solder the IC connection.
4. Route the jumper wire along the path of the out-away copper
pattern and let it overlap the previously scraped end of the good
copper pattern. Solder the overlapped area and clip off any
excess jumper wire.
At Other Connections
Use the following technique to repair the defective copper pattern
at connections other than IC Pins. This technique involves the
installation of a jumper wire on the component side of the circuit
board.
1. Remove the defective copper pattern with a sharp knife.
Remove at least 1/4 inch of copper, to ensure that a hazardous
condition will not exist if the jumper wire opens.
2. Trace along the copper pattern from both sides of the pattern
break and locate the nearest component that is directly
connected to the affected copper pattern.
3. Connect insulated 20-gauge jumper wire from the lead of the
nearest component on one side of the pattern break to the lead
of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so the
it does not touch components or sharp edges.
- 6 -
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement
.
4. General Specification(TV)
No Item Specification Remark
1 Receiving System ATSC/64 & 256 QAM/ NTSC-M
2 Available Channel 1) VHF : 02~13
2) UHF : 14~69
3) DTV : 02-69
4) CATV : 01~135
5) CADTV : 01~135
3 Input Voltage 100-240V~, 50/60Hz
4 Market NORTH AMERICA
5 Screen Size 20 inch Wide For 20LC7D-UB
23 inch Wide For 23LC7D-UB
6 Aspect Ratio 16:9
7 Tuning System FS
8 LCD Module T200XW02 Wide, AUO
T230XW01 Wide, AUO
9 Operating Environment 1) Temp : 0 ~ 40 deg
2) Humidity : ~ 80 %
10 Storage Environment 1)Temp : -20 ~ 60 deg
2) Humidity : 0 ~ 90 %
1. Application range
1) This spec sheet is applied all of the 20/23" LCD TV with
LA74E chassis.
2) Not included spec and each product spec in this spec sheet
apply correspondingly to the following each country
standard and requirement of Buyer
2. Specification
Each part is tested as below without special appointment.
1) Temperature : 20±5°C
2) Relative Humidity : 65±10%
3) Power Voltage : Standard input voltage
(100-240V@50/60Hz)
* Standard Voltage of each product is marked by models
4) Specification and performance of each parts are followed
each drawing and specification by part number in
accordance with BOM.
5) The receiver must be operated for about 20 minutes prior to
the adjustment.
3. Test method
1) Performance : LGE TV test method followed
2) Demanded other specification
Safety : UL, CSA, IEC specification
EMC : FCC, ICES, IEC specification
5. Chroma & Brightness
5.1. FOR 23LC7D (CONDITION : EZ-Picture "Daylight")
- 7 -
No Item Min Typ Max Unit
1 White peak brightness 360 450 cd/m
260 450 cd/m
2 Contrast ratio 550 700
400 700 Refer to LCD SPEC.
3 Brightness uniformity 1.25
4 Color coordinate RED X Typ -0.03 0.638 Typ +0.03
5 Y Typ -0.03 0.337 Typ +0.03
6 GREEN X Typ -0.03 0.299 Typ +0.03
7 Y Typ -0.03 0.604 Typ +0.03
8 BLUE X Typ -0.03 0.145 Typ +0.03
9 Y Typ -0.03 0.059 Typ +0.03
10 WHITE X Typ -0.03 0.280 Typ +0.03
11 Y Typ -0.03 0.292 Typ +0.03
12 White Balance Target Cool X Typ -0.015 0.274 Typ +0.015
13 Y Typ -0.015 0.274 Typ +0.015
14 Medium X Typ -0.015 0.287 Typ +0.015
15 Y Typ -0.015 0.289 Typ +0.015
16 Warm X Typ -0.015 0.314 Typ +0.015
17 Y Typ -0.015 0.318 Typ +0.015
18 Viewing angle 140 176 Right / Left
19 140 176 Up / Down
20 Color Temperature Medium 8,300 9,300 10,300
Cool 11,000 12,000 13,000
Warm 5,500 6,500 7,500
- 8 -
5.1. FOR 20LC7D (CONDITION : EZ-Picture "Daylight")
6. Component Video Input (Y, CB/PB, CR/PR)
No Resolution H-freq(kHz) V-freq(Hz) Pixel clock Proposed
1. 720*480 15.73 59.94 SDTV ,DVD 480I
2. 720*480 15.73 60.00 SDTV ,DVD 480I
3. 720*480 31.47 59.94 SDTV 480P
4. 720*480 31.50 60.00 SDTV 480P
5. 1280*720 44.96 59.94 HDTV 720P
6. 1280*720 45.00 60.00 HDTV 720P
7. 1920*1080 33.72 59.94 HDTV 1080I
8. 1920*1080 33.75 60.00 HDTV 1080I
No Item Min Typ Max Unit Remark
1. White peak brightness 360 450 cd/m
2
250 450 cd/m
2
PSM : Daylight
2. Contrast Ratio 600 700
400 700 PSM : Daylight
3. Brightness uniformity 1.25 Refer to LCD SPEC.
4. Color coordinate RED X 0.640 +/- 0.03
Y 0.330 +/- 0.03
GREEN X 0.290 +/- 0.03
Y 0.600 +/- 0.03
BLUE X 0.150 +/- 0.03
Y 0.060 +/- 0.03
WHITE X 0.295 +/- 0.03
Y 0.305 +/- 0.03
5. White Balance Target Cool X 0.274 +/- 0.015
Y 0.274 +/- 0.015
Medium X 0.287 +/- 0.015
Y 0.289 +/- 0.015
Warm X 0.314 +/- 0.015
Y 0.318 +/- 0.015
6. Viewing angle 130 160 Right / Left
110 140 Up / Down
7. Color Temperature Medium 8,300 9,300 10,300 <Test Signal>
Cool 11,000 12,000 13,000 85 IRE
Warm 5,500 6,500 7,500
No. Item Content Remark
1 Product Dimension Width(W) Length(D) Height(H)
Before Packing 499.6 175.0 401.4 Head depth : 73.0mm
After Packing 563.0 173.0 423.0 (stand detachable, 3 piece type)
2 Product Weight Only SET 6.22 Kg
With Box 7.73 Kg
3 Container Loading Quantity Individual or Palletizing 20 ft 40 ft 40 ft_HC
Indi. Wooden Indi. Wooden Indi. Wooden
689 576 1443 1296 1665 1512
4 Appearance General
- 9 -
8. Mechanical specification
<20LC7D>
<23LC7D>
7. RGB input (PC/DTV)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed
PC
1 640*350 31.469 70.08 25.17 DOS O
2 720*400 31.469 70.08 28.32 DOS O
3 640*480 31.469 59.94 25.17 VESA(VGA) O
4 800*600 37.879 60.31 40.00 VESA(SVGA) O
5 1024*768 48.363 60.00 65.00 VESA(XGA) O
6 1280*768 47.776 59.87 79.50 VESA(WXGA) O
7 1360*768 47.712 60.01 85.50 VESA(WXGA) O
8 1366*768 60.023 60.00 80.00
No. Item Content Remark
1 Product Dimension Width(W) Length(D) Height(H)
Before Packing 581.5 198.8 458.3 Head depth : 82mm
After Packing 655.0 186.0 490.0 (stand detachable, 3 piece type)
2 Product Weight Only SET 7.9 Kg
With Box 9.8 Kg
3 Container Loading Quantity Individual or Palletizing 20 ft 40 ft 40 ft_HC
Ind. Wooden Indi. Wooden Indi. Wooden
468 396 1008 924 1176 1092
4 Appearance General
- 10 -
ADJUSTMENT INSTRUCTION
1. Application Object
These instructions are applied to all of the LCD TV, LA74E.
2. Notes
(1) Because this is not a hot chassis, it is not necessary to use
an isolation transformer. However, the use of isolation
transformer will help protect test equipment.
(2) Adjustments must be done in the correct order.
(3) The adjustments must be performed in the circumstance of
20±5°C of temperature and 65±10% of relative humidity if
there is no specific designation.
(4) The input voltage of the receiver be must kept 110V, 60Hz
when adjusting.
(5) The receiver must be operational for about 15 minutes
prior to the adjustments.
(6) Perform preliminary operation after receiving 100% White
Pattern (06CH). (Or 3. White Pattern status of Ez-Adjust)
- White Pattern entry method
1) Enter into Ez-Adjust by pressing the ADJ key on the
adjustment R/C.
2) 100% FULL WHITE PATTERN appears if pressing the
OK (
A
) key after selecting the 3.WHITE PATTERN with
the CH + / - KEY.
* It is possible to heat run the set without a separate signal
generator in this mode.
Caution : Care must be taken as afterimage phenomena
may occur about the black level part of screen If leaving
pause image turned on for more than 20 minutes
(especially inner digital pattern (13 CH), Cross Hatch
Pattern (09CH) with significant black/white contrast).
3. MICOM Download(Option)
3-1. Required Test Equipment
(1) JIG-LEVER TYPE for adjusting: 1EA
(2) PC & MONITOR: 2EA
(3) BOARD for INTERFACE: IIC & ISP BOARD: 2EA
(4) 15P D-SUB CABLE: 2EA
(5) Using the 12/15 line of D-SUB 15P
12-SDA/15-SCL
3-2. JIG Connection
3-3. Establishment Program
(1) Establish LGE Monitor Tools v1.1
(2) The program work and it is opened program window as
seen below.
(3) Click the first icon shown in fig.9. The window seen in
fig.10 should appear.
- 11 -
3-4. Set Method
(1) MCU Select: MTV512M64
(2) Option
R/W Option: Auto Write(Verity)
Jig Option: Myson
Transmit Speed: Medium
(3) Check: Just do it with blank micom.
(4) PORT
Chose Parallel Port (normal LPT1)
Attention:You must chose EPP when select Rom BIAS at LPT
3-5. Download Method
(1) Click the Load File.
(2) Locate and select the correct file from your computer.
(*.hex).
(3) Click the Send.
(4) When you see (ISP COMPLETE) the download is complete.
4. ADC-Set Adjustment
4-1. Synopsis
ADC-Set adjustment to set the black level and the Gain to
optimum.
4-2. Test Equipment
Service R/C, 801GF(802V, 802F, 802R) or MSPG925FA
Pattern Generator
(480i/1080i The Horizontal 100% Color Bar Pattern adjust to
within 0.7±0.1Vp-p)
4-3. Adjustment
(1) Select Component as the input with 100% Horizontal Color
Bar Pattern(HozTV31Bar) in 480i Mode
(2) After receiving signal for at least 1 second, press the ADJ
Key on the Service R/C to enter the ‘Ez - Adjust’ and select
the ‘2. ADC 480i Comp1’.
Pressing the Enter Key to adjust automatically.
(3) When the adjustment is over, 'MST3361 Component
Success’ is displayed. If the adjustment has errors,
'MST3361 Configuration Error’ is displayed.
(4) Select Component 1 as the input with 100% Horizontal
Color Bar Pattern(HozTV31Bar) in 1080i Mode.
(5) After receiving signal for at least 1 second, press the ADJ
Key on the Service R/C to enter the ‘Ez - Adjust’ and select
the ‘3. ADC 1080i Comp1/RGB’.
Pressing the Enter Key to adjust automatically.
(6) When the adjustment is over, 'MST3361 Component
Success’ is displayed. If the adjustment has errors,
'MST3361 Configuration Error’ is displayed.
(7) After the Component MST3361 adjustment is over, convert
the RGB-DTV Mode and display Pattern.
When the adjustment is over, 'MST3361 RGB_DTV
Success’ is displayed.
(8) Readjust after confirming the case Pattern or adjustment
condition where the adjustment errors.
(9) After adjustment is complete, exit the adjustment mode by
pressing the ADJ KEY.
Ez Adjust
1. CVBS ACC Adjust
2. ADC 480i Comp1
3. ADC 1080i Co mp1/ RGB
4. Reserved
5. Sub- Brightness/Contrast
6. White-Balance
7. Module Control
8. Temperature Threshold
9. White-Pattern
10. 2 Hour Off Option
<Adjustment Mode>
<Adjustment Pattern: 480i/1080i 60Hz HozTV31Bar Pattern>
5. EDID (The Extended Display Identification Data)
/ DDC (Display Data Channel) Download
This is the function that enables “Plug and Play".
5-1. HDMI EDID Data Input
(1) Required Test Equipment
1) PC, Jig for adjusting DDC. (PC serial to D-sub
Connection equipment)
2) S/W for writing DDC(EDID data write & read)
3) D-Sub cable
(2) Preparation for Adjustments & Setting of Device
1) Set devices as below and turn on the PC and JIG.
2) Open S/W for writing DDC (EDID data write & read).
(operated in DOS mode)
6-2. EDID DATA
(1) 23LS7D-UB : RGB
EDID Block 0, Byte 0 - 127 [00H-7FH]
Block Type : EDID 1.3
(2) 20LS7D-UB : RGB
EDID Block 0, Byte 0 - 127 [00H-7FH]
Block Type : EDID 1.3
(3) 23LS7D-UB : HDMI
EDID Block 0, Byte 0 - 127 [00H-7FH]
Block Type : EDID 1.3
EDID Block 1, Byte 128 - 255 [80H-FFH]
Block Type : CEA EDID Timing Extension Version 3
(4) 20LS7D-UB : HDMI
EDID Block 0, Byte 0 - 127 [00H-7FH]
Block Type : EDID 1.3
EDID Block 1, Bytes 128-255 [80H-FFH]
Block Type: CEA EDID Timing Extension Version 3
0123456789ABCDEF
0 00FFFFFFFFFFFF001E6D01 00 01 01 01 01
10 00 10 01 03 68 33 1D 96 0A E6 98 A3 54 4A 99 26
20 0F 4B 4E A1 08 00 01 01 01 01 01 01 01 01 01 01
30 01 01 01 01 01 01 64 19 00 40 41 00 26 30 18 88
40 36 00 98 07 32 00 00 18 0E 1F 00 80 51 00 1E 30
50 40 80 37 00 C4 8E 21 00 00 1C 66 21 50 B0 51 00
60 1B 30 40 70 36 00 C4 8E 21 00 00 1E 00 00 00 FC
70 00 32 33 4C 53 32 44 0A 20 20 20 20 20 20 00 6C
- 12 -
PDP TV SET
(or Digital Board)
<Fig. 2>
0123456789ABCDEF
0 00FFFFFFFFFFFF001E6D01 00 01 01 01 01
10 00 10 01 03 68 2C 19 96 0A E6 98 A3 54 4A 99 26
20 0F 4B 4E A1 08 00 01 01 01 01 01 01 01 01 01 01
30 01 01 01 01 01 01 64 19 00 40 41 00 26 30 18 88
40 36 00 98 07 32 00 00 18 0E 1F 00 80 51 00 1E 30
50 40 80 37 00 C4 8E 21 00 00 1C 66 21 50 B0 51 00
60 1B 30 40 70 36 00 C4 8E 21 00 00 1E 00 00 00 FC
70 00 32 30 4C 53 32 44 0A 20 20 20 20 20 20 00 7A
0123456789ABCDEF
0 00FFFFFFFFFFFF001E6D01 00 01 01 01 01
10 00 10 01 03 80 33 1D 96 0A CF 74 A3 57 4C B0 23
20 09 48 4C 2F CE 00 31 40 45 40 61 40 01 01 01 01
30 01 01 01 01 01 01 66 21 50 B0 51 00 1B 30 40 70
40 36 00 C4 8E 21 00 00 1E 0E 1F 00 80 51 00 1E 30
50 40 80 37 00 C4 8E 21 00 00 1C 00 00 00 FD 00 38
60 4B 1F 3C 09 00 0A 20 20 20 20 02 20 00 00 00 FC
70 00 32 33 4C 53 37 44 2D 55 42 0A 20 20 20 01 B5
0123456789ABCDEF
0 020315F1468405030220222315075065
10 03 0C 00 10 00 01 1D 00 72 51 D0 1E 20 6E 28 55
20 00 C4 8E 21 00 00 1E 01 1D 80 18 71 1C 16 20 58
30 2C 25 00 C4 8E 21 00 00 9E 8C 0A D0 8A 20 E0 2D
40 10 10 3E 96 00 C4 8E 21 00 00 18 8C 0A D0 8A 20
50 E0 2D 10 10 3E 96 00 13 8E 21 00 00 18 00 00 00
60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 A7
0123456789ABCDEF
0 00FFFFFFFFFFFF001E6D01 00 01 01 01 01
10 00 10 01 03 80 2C 19 96 0A CF 74 A3 57 4C B0 23
20 09 48 4C 2F CE 00 31 40 45 40 61 40 01 01 01 01
30 01 01 01 01 01 01 66 21 50 B0 51 00 1B 30 40 70
40 36 00 C4 8E 21 00 00 1E 0E 1F 00 80 51 00 1E 30
50 40 80 37 00 C4 8E 21 00 00 1C 00 00 00 FD 00 38
60 4B 1F 3C 09 00 0A 20 20 20 20 02 20 00 00 00 FC
70 00 32 30 4C 53 37 44 2D 55 42 0A 20 20 20 01 C3
0123456789ABCDEF
0 020315F1468405030220222315075065
10 03 0C 00 10 00 01 1D 00 72 51 D0 1E 20 6E 28 55
20 00 C4 8E 21 00 00 1E 01 1D 80 18 71 1C 16 20 58
30 2C 25 00 C4 8E 21 00 00 9E 8C 0A D0 8A 20 E0 2D
40 10 10 3E 96 00 C4 8E 21 00 00 18 8C 0A D0 8A 20
50 E0 2D 10 10 3E 96 00 13 8E 21 00 00 18 00 00 00
60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 A7
- 13 -
7. Adjustment of White Balance
7-1. Required Equipment
(1) Color analyzer (CA-100 or CA210 similar product)
(2) Automatic adjustor (with automatic adjustment necessity
and the RS-232C communication being possible)
7-2. Connection Diagram of Equipment
for Measuring (Automatic Adjustment)
* RS-232C Command (Automatic Adjustment)
7-3. Adjustment of White Balance(manual)
(1) Enter ‘Ez - Adjust’ by pressing ADJ KEY on the Service
Remote Control.
(2) Select "9. TEST PATTERN" using CH +/- Key and HEAT
RUN at least 30 minutes by pressing the ENTER Key.
(3) Calibrate of the CA100+, then attach sensor to LCD
module surface when you adjust.
(4) After attaching sensor to center of screen, select ‘6. White-
Balance’ of ‘Ez - Adjust’ by pressing the ADJ KEY on the
Service R/C. Then enter adjustment mode by pressing the
Right KEY (
G
).
(5) Set test-pattern on and display inside pattern. Control is
carried out on there color temperature, COOL, MEDIUM,
WARM.
* Fix all color temperature to 64.
* Color Temperature: Cool, Medium, Warm
1. When R GAIN is set to 192
- Control G GAIN and B GAIN by lowering from 192.
2. When B GAIN is set to 192
- Control R GAIN and G GAIN by lowering from 192.
3. When G GAIN is set to 192
- Control R GAIN and B GAIN by lowering from 192.
One of R Gain / G Gain / B Gain should be kept on 192, and
adjust other two lower than 192.
(When R/G/B GAIN are all 192, it is the FULL DYNAMIC
Range of Module)
Full White Pattern
COLOR
ANALYZER
TYPE; CA-210+
<Fig. 3> Connection Diagram of Automatic Adjustment
R Gain
G Gain
B Gain
R Cut
G Cut
B Cut
Jg
Jh
Ji
Cool
Ja
Jb
Jc
Mid
RS-232C COMMAND
[CMD ID DATA]
CENTER
(DEFAULT)(Decimal)
Jd
Je
Jf
00
00
00
192
192
192
Warm
Min
Max
(Deci
mal)
64
64
64
Cool
64
64
64
Mid
64
64
64
Warm
- 14 -
1. TV/CATV doesn't display
Check TU4002 Pin9(Video output)
Can you see the normal signal?
Could you measure voltage of
TU4002 & IIC lines?
Are they all normal?
You should replace TUNER.
You should check power line
& IIC lines.
Check the input(Pin63) of AV switch(IC5003).
Can you see the normal waveform?
After checking the Power of AV switch you should
decide to replace AV switch or not.
Yes
Yes
No No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Check the output(Pin56) of AV switch(IC5003).
Can you see the normal waveform?
After checking the Power of AV switch you should
decide to replace AV switch or not.
Check the input(Pin1) of LPF(IC4006).
Can you see the normal waveform?
After checking the Power of LPF you should
decide to replace LPF or not.
Check the output(Pin8) of LPF(IC4006).
Can you see the normal waveform?
After checking the Power of LPF you should
decide to replace LPF or not.
Check the input(PinH26) of BCM3550(IC4006).
Measure waveform at C1010 because it’s more
easy to check.
Can you see the normal waveform?
This board has big problem because Main chip
(BCM3550) have some troubles.
After checking thoroughly all path once again,
You should decide to replace BCM3550 or not.
TROUBLESHOOTING
- 15 -
2. Video doesn't display
Check J5007 Pin2
Can you see the normal waveform?
J5007 may have problem. Replace this Jack.
Check the input(Pin1) of AV switch (IC5003).
Pin1 is for video1,Pin8 is for video 2.
Can you see the normal waveform?
After checking the Power of AV switch you should
decide to replace AV switch or not.
Yes
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Check the output(Pin56) of AV switch(IC5003).
Can you see the normal waveform?
After checking the Power of AV switch you should
decide to replace AV switch or not.
Check the input(Pin1) of LPF(IC4006).
Can you see the normal waveform?
After checking the Power of LPF you should
decide to replace LPF or not.
Check the output(Pin8) of LPF(IC4006).
Can you see the normal waveform?
After checking the Power of LPF you should
decide to replace LPF or not.
Check the input(PinH26) of BCM3550(IC1001).
Measure waveform at C1010 because it’s more
easy to check.
Can you see the normal waveform?
This board has big problem because
Main chip(BCM3550) have some troubles.
After checking thoroughly all path once again, You
should decide to replace BCM3550 or not.
- 16 -
3. Component doesn't display
Check J5004
Can you see the normal waveform?
J5004 may have problem. Replace this Jack.
Check the input of Component switch(IC5001).
Can you see the normal waveform?
After checking the input TR of component, you
should decide to replace component switch or not.
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Check the output of Component switch(IC5001).
Can you see the normal waveform?
After checking the Power of component switch
you should decide to replace component switch or
not.
Yes
Check the input of MST3361(IC7012, Pin 6,9,12).
Can you see the normal waveform?
After checking the Power of MST3382M you
should
decide to replace MST3382M or not.
Check the output of MST3361(IC7012 ).
Can you see the normal waveform?
After checking the Power of MST3361 you should
decide to replace MST3361 or not.
Check the input and output of BCM3550(IC1001).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
This board has big problem because
Main chip(BCM3550) have some troubles.
After checking thoroughly all path once again,
You should decide to replace BCM3550 or not.
- 17 -
4. RGB_PC doesn't display
Check input connect P7004.
Can you see the normal waveform?
P7004 may have problem. Replace this Jack.
Check the input of Component switch(IC5001).
Can you see the normal waveform?
After checking the input TR of RGBHV, you
should decide to replace these components or
not.
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Check the output of Component switch(IC5001).
Can you see the normal waveform?
After checking the Power of RGB switch you
should decide to replace component switch or not.
Yes
Check the input of MST3361(IC7012, Pin 6,9,12).
Can you see the normal waveform?
After checking the Power of MST3382M you
should decide to replace MST3382M or not.
Check the input of MST3361(IC7012).
Can you see the normal waveform?
After checking the Power of MST3382M you
should decide to replace MST3382M or not.
Check the input and output of BCM3550(IC1001).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
This board has big problem because
Main chip(BCM3550) have some troubles.
After checking thoroughly all path once again,
You should decide to replace BCM3550 or not.
- 18 -
5. HDMI doesn't display
Check input connect J7101.
Can you see the normal waveform?
J7101 may have problem. Replace this Jack.
Check DDC communication lines(IC702 Pin5,6)
After checking the Power of this chip, you should
decide to replace this or not.
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Check HDCP communication lines(IC701 Pin5,6)
After checking the Power of this chip, you should
decide to replace this or not.
Yes
Check the input of MST3382M(IC7012).
This signal is TMDS.
Can you see the normal waveform?
After checking the trace of TMDS lines and power
of MST3382M, you should decide to replace
MST3382M or not.
Check the output of MST3361(IC7012)
Can you see the normal waveform?.
After checking the Power of MST3361 you should
decide to replace MST3361 or not.
Check the input and output of BCM3550(IC1001).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
This board has big problem because
Main chip(BCM3550) have some troubles.
After checking thoroughly all path once again,
You should decide to replace BCM3550 or not.
BLOCK DIAGRAM
- 19 -
CXA2069Q
(IC5003)
LCD
Module
SVHS
BCM3550KPB5G
(IC1001)
MST3382M
(IC7004)
EEPROM
CVBS
LCDS
TV Tuner
AT_TU_V
MM1731XVBE
(IC5001)
RGB
Y PB PR
COM_Y PB PR
Y CB CR
RGB_LR
AUO_LR
COM_LR
FMS6400S
(IC4006)
M_YC
MAIN Y
MAIN_C
SP (R)
SP (L)
SP_L SP_R
P7009
P7010
Earphone
MC33078DR
(IC7002)
C55331A
(IC7001)
I2S M_CLK
HY5DU561622ETP
DDR (IC2002)
HY5DU561622ETP
DDR (IC2003)
DDR_ADD
DDR_ADD
DDR_DATA
DDR_DATA
S29GL128N90TF
FLASH (IC2001)
EBI_ADD
EBI_PCI
THC63LVDM
(IC6004)
XDR_DATA
(0..7) x3
MP1593DN
IC6001
12V
5V
SI4925DY
Q6002
12V
12V
AUO 20
LPL 23
"
TPS2052B
(IC3001)
SIF
IF_P/ IF_N
IF_AGC
RF_AGC
MTV416GMF
(IC4015)
UCOM_Rx Tx
BCM_Rx Tx
RS-232
USB
EEPROM
74LVC14
KIA7029
BCM_RESET
KIA7029
EEPROM
AT24C512
I2C_0
I2C_1
I2C_2
DDC_I2C
I2C_3
12.0V
Power
Filter
12V
15V
Inverter(10Lamps)
24V
24V
3.3V
6V
P4003
P4007
KEY1
KEY2
IR
LRD_G
LRD_R
5V
5V_TU
SC1566
3.3V
2.6V
PQ05DZ
6.0V
5.0V
KA7809A
9.0V
SC4519S
3.3V
1.2V
AZ1117H
5.0V
3.3V
BA033FP
ST 5.0V
3.3VST
ST5V
IC3232
3.3V
3.3VST_MICOM
P4004
6.0V
5V_MNT
ST_5V
LIVE_ON
PWM_DIM
PDD/INV
INV_ON
AL_ON
AC_DET
3.3VST_MICOM
ST5V
2.6V_BCM
2.6V_BCM
3.3V
D3.3V_BCM
D2.6V_BCM A2.6V_BCM
3.3V
5V
9V
3.3V
A1.2V_BCM
A3.3V_BCM
15V
5V
9V
3.3V_MST
POWER
SC2595S
D2.5V_BCM
DDR_1.25V
KIA78R05
+6.0V
+5.0V
HDMI
CM2021
EEPROM
EEPROM
YDA-138
AMP (IC7017)
"
- 20 -
EXPLODED VIEW
300
200
580
520
521
530
531
400
431
430
440
450
120
590
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
-
1
-
2
-
3
-
4
-
5
-
6
-
7
-
8
-
9
-
10
-
11
-
12
-
13
-
14
-
15
-
16
-
17
-
18
-
19
-
20
-
21
-
22
-
23
-
24
-
25
-
26
-
27
-
28
-
29
-
30
-
31
-
32
-
33
-
34
-
35
-
36
LG Electronics 20LS7D(C)-UB User manual
- Category
- TVs & monitors
- Type
- User manual
Ask a question and I''ll find the answer in the document
Finding information in a document is now easier with AI
Related papers
-
LG Electronics 37LC2R User manual
-
LG 32LS5610/561T User manual
-
-
LG 32LG3000 User manual
-
-
-
-
-
LG 42LM620T-ZE User manual
-