Download Black Box IC108C Specifications

Direct View LCD
42LG60
Fall 2008
OUTLINE
Section 1
Contact Information, Preliminary Matters, Specifications,
LCD Overview, General Troubleshooting Steps,
Signal Distribution, Disassembly Instructions and Voltages
Section 2
Circuit Board Operation, Troubleshooting of :
• Switch mode Power Supply
• Main Board
• Control Board
• T-CON Board
• Ft Control Board
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42LG60
Overview of Topics to be Discussed
42LG60 LCD Direct View Display
Section 1
This Section will cover Contact Information and remind the Technician of Important Safety Precautions for
the Customers Safety as well as the Technician and the Equipment.
Basic Troubleshooting Techniques which can save time and money sometimes can be overlooked. These
techniques will also be presented.
This Section will get the Technician familiar with the Disassembly, Identification and Layout of the LCD
Display Panel.
At the end of this Section the Technician should be able to Identify the Circuit Boards and have the ability
and knowledge necessary to safely remove and replace any Circuit Board or Assembly.
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Preliminary Matters (The Fine Print)
IMPORTANT SAFETY NOTICE
The information in this training manual is intended for use by persons possessing an adequate background in
electrical equipment, electronic devices, and mechanical systems. In any attempt to repair a major Product,
personal injury and property damage can result. The manufacturer or seller maintains no liability for the
interpretation of this information, nor can it assume any liability in conjunction with its use. When servicing this
product, under no circumstances should the original design be modified or altered without permission from LG
Electronics. Unauthorized modifications will not only void the warranty, but may lead to property damage or
user injury. If wires, screws, clips, straps, nuts, or washers used to complete a ground path are removed for
service, they must be returned to their original positions and properly fastened.
CAUTION
To avoid personal injury, disconnect the power before servicing this product. If electrical power is required for
diagnosis or test purposes, disconnect the power immediately after performing the necessary checks. Also be
aware that many household products present a weight hazard. At least two people should be involved in the
installation or servicing of such devices. Failure to consider the weight of an product could result in physical
injury.
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ESD Notice
(Electrostatic Discharge Notice)
Today’s sophisticated electronics are electrostatic discharge (ESD) sensitive. ESD can weaken or damage
the electronics in a manner that renders them inoperative or reduces the time until their next failure.
Connect an ESD wrist strap to a ground connection point or unpainted metal in the product. Alternatively,
you can touch your finger repeatedly to a ground connection point or unpainted metal in the product. Before
removing a replacement part from its package, touch the anti-static bag to a ground connection point or
unpainted metal in the product. Handle the electronic control assembly by its edges only. When
repackaging a failed electronic control assembly in an anti-static bag, observe these same precautions.
REGULATORY INFORMATION
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to
Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference when the equipment is operated in a residential installation. This equipment generates, uses,
and can radiate radio frequency energy, and, if not installed and used in accordance with the instruction
manual, may cause harmful interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation. If this equipment does cause harmful interference to
radio or television reception, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate
the receiving antenna; Increase the separation between the equipment and the receiver; Connect the
equipment to an outlet on a different circuit than that to which the receiver is connected; or consult the
dealer or an experienced radio/TV technician for help.
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CONTACT INFORMATION
Customer Service (and Part Sales)
(800) 243-0000
Technical Support (and Part Sales)
(800) 847-7597
USA Website (GCSC)
aic.lgservice.com
Customer Service Website
us.lgservice.com
LG Web Training
lge.webex.com
LG CS Academy
lgcsacademy.com
http://136.166.4.200
LCD-DV: 32LG40, 32LH30, 42LG60, 42LG70, 42LH20, 42LH40, 42LH50, 47LG90
PLASMA: 42PG20, 42PQ20, 42PQ30, 50PG20, 50PS80, 50PS60
Also available on the
Plasma page
Plasma Panel
Alignment Handbook
New Training Materials on
the Learning Academy site
Published August 2009 by LG Technical Support and Training
LG Electronics Alabama, Inc. 201
James Record Road, Huntsville,
AL, 35813.
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Safety and Handling and Checking Points
Safety and Handling Regulations
1. Approximately 20 minute pre-run time is required before any adjustments are performed.
2. Refer to the Voltage Sticker on the Switch Mode Power Supply silk screening. (+/- ½ volt).
3. Be cautious of electric shock from the Backlight section, it uses high voltage AC. Check that
the Power Supply and Drive Circuits are completely discharged because of residual current
stored before Circuit Board removal.
4. C-MOS circuits are sensitive to static electricity.
Use caution when dealing with these IC and circuits.
5. Exercise care when making voltage and waveform checks to prevent costly short circuits
from damaging the unit.
6. Be cautious of lost screws and other metal objects to prevent a possible short in the
circuitry.
Checking Points to be Considered
1. Check the appearance of the Replacement Panel and Circuit Boards for both physical damage
and part number accuracy.
2. Check the model label. Verify model names and board model matches.
3. Check details of defective condition and history. Example: Oscillator failure dead set, etc…
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Basic Troubleshooting Steps
Define, Localize, Isolate and Correct
•Define
Look at the symptom carefully and determine what circuits could be causing
the failure. Use your senses Sight, Smell, Touch and Hearing. Look for burned parts and
check for possible overheated components. Capacitors will sometimes leak dielectric material
and give off a distinct odor. Frequency of power supplies will change with the load, or listen for
relay closing etc. Observation of the front Power LED may give some clues.
•Localize
After carefully checking the symptom and determining the circuits to be
checked and after giving a thorough examination using your senses the first check should
always be the DC Supply Voltages to those circuits under test. Always confirm the supplies
are not only the proper level but be sure they are noise free. If the supplies are missing check
the resistance for possible short circuits.
•Isolate
To further isolate the failure, check for the proper waveforms with the
Oscilloscope to make a final determination of the failure. Look for correct Amplitude Phasing
and Timing of the signals also check for the proper Duty Cycle of the signals. Sometimes
“glitches” or “road bumps” will be an indication of an imminent failure.
•Correct
The final step is to correct the problem. Be careful of ESD and make sure to
check the DC Supplies for proper levels. Make all necessary adjustments and lastly always
perform a Safety AC Leakage Test before returning the product back to the Customer.
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42LG60 PRODUCT INFORMATION SECTION
Side View
This section of the manual will discuss the specifications of the 42LG60
“Thin” LCD Direct View Display Panel.
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42LG60
Basic Specifications
• Full HD 1080p Resolution (1920 x 1080)
• 50,000:1 Dynamic Contrast Ratio
• TruMotion 120Hz
• 4x HDMI™ V.1.3 with Deep Color
• Intelligent Sensor
• 24p Real Cinema
• AV Mode (Cinema, Sports, Game)
• Clear Voice
• LG SimpLink™ Connectivity
• Invisible Speaker System
• USB 2.0 (JPEG, MP3)
• ISFccc
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LOGO Familiarization
Full HD 1080p Resolution
Displays HDTV programs in full 1920 x 1080p resolution for a more detailed picture.
TruMotion 120Hz
Advance 120Hz panel provides clear, smooth images, even during fast action
scenes creating a stable structure for a crisper picture.
Intelligent Sensor
Unlike other sensors which can only sense brightness of ambient light, LG’s
“Intelligent Sensor” uses 4,096 sensing steps to evaluate its surroundings. Using a
sophisticated algorithm, the LG processes picture quality elements including
brightness, contrast, color, sharpness and white balance. The result is a picture
optimized for it’s surroundings, more pleasing to watch and which can also save up
to 50% in power consumption.
24p Real Cinema
Hi-def movies run at exactly 24 frames per second speed that they were originally
filmed in, making your home-cinema experience one step closer to a “Real Cinema”
experience.
Clear Voice Technology
Automatically enhances and amplifies the sound of the human voice frequency
range to provide high-quality dialogue when background noise swells.
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Remote Control
BOTTOM PORTION
TOP PORTION
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Accessing the Service Menu
REMOTE
TOP PORTION
SIDE KEYS
To access the Service Menu.
1) Turn the Set On
2) Simultaneously, Press and
“Hold” the Menu Key on the
Side Key pad and Press and
“Hold” the Menu Key on the
Remote approximately 5
seconds.
3) If Customer’s Menu appears,
continue to hold until it
disappears.
4) The Service Menu appears
Note: Dependant upon the Software Version, a Password
may be required to enter the Service Menu.
If a password is required, enter
0000
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42LG60
Rear and Side Input Jacks
Rear Input Jacks
Side Input Jacks
Main PWB
Orientation
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42LG60
USB Download Screen (Software Update)
1) Create an LG_DTV folder on the USB Flash Drive
Shows the
Currently
Installed
Version
2) Copy new software (xxx.epk) to "LG_DTV"
folder. Make sure to have correct software file.
3) With TV turned on, insert USB flash drive.
4) You can see the message
“TV Software Upgrade” (See figure to right)
5) Cursor left and highlight "START" Button and
push “Enter” button using the remote control.
6) You can see the download progress Bar.
7) Do not unplug until unit has automatically
restarted.
8) When download is completed, you will see
“COMPLETE”.
9) Your TV will be restarted automatically.
Shows the
Software
Version
found on the
USB Flash
Drive
Shows the
Software file found
on the USB Flash
Drive
* CAUTION:
Do not remove AC power or the USB Flash Drive.
Do not turn off Power, during the upgrade
process.
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42LG60 Dimensions
There must be at least 4 inches of Clearance on all sides
40-7/8"
1038.86mm
7-7/8"
200mm
15-13/16"
402mm
8"
204.4mm
6-5/8"
168.78mm
Center
31-5/16"
795mm
29-3/8"
746.76mm
14-11/16"
373.38mm
2-3/8"
60.96mm
11-7/8"
301mm
3-7/8"
100mm
Model No.
Serial No.
Label
Remove 4 screws to
remove stand for
wall mount
1-15/16"
49.2mm
Weight without Stand: 45 lb
Weight with Stand: 53.1 lb
20-1/2"
520.7mm
16
14-7/8"
376.46mm
DISASSEMBLY AND TROUBLESHOOTING SECTION
This section of the manual
will discuss disassembly and
troubleshooting.
Upon completion of this section the Technician will have a
better understanding of how to diagnosis and resolve problems.
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Removing the Back Cover
The Stand does not need to be removed
Remove the 13 screws indicated.
Pay attention to the size and type of screw
as there are many different types.
Putting in the improper screw when
reassembling may Cause damage.
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Circuit Board Layout
T-CON EAT56803901
(Shield Removed)
LVDS
Cables
Backlight
Power Connection
Backlight
Power Connection
LVDS Cables
TruMotion
Board
Ft Control Board
Side
Key
Board
Side
Inputs
POWER SUPPLY
(SMPS) Board
Touch LED
Main “Digital” Board
Invisible Speakers
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42LG60
Backlight Information
Back View 18 Bulbs
To Backlights
Over 1.2KV
Power Supply with Ballast
EEFL (External Electrode Fluorescent Lamp)
LOW COST Large number of lamps driven by a single inverter
2.8V~3.1V RMS
20
58Khz
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42LG60
Introducing EEFL and CCFL
Simple structure, Low price
Simple structure
Complicated structure
Lamp manufacturing process
Lamp assembly structure
21
Low Cost
Large number of Lamp
Drive by single inverter
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42LG60
Electrode Differences between the EEFL and CCFL
Key: Long Life Time
• For CCFL, Hg gas is consumed mainly near the internal electrode
• For EEFL, longer life time is expected because there is no internal electrode consuming Hg gas
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POWER SUPPLY (SMPS) PWB SECTION
P2
To Main
P401
Heat Sink is
Hot Ground
Shock Hazard
Ballast
Section
P402
F700
5A/250V
335V
INPUT AC 100V ~ 240V (50/60Hz) 3A
OUTPUT
P401 and P402
TO BACKLIGHT
CONNECTORS
AC IN
F101
8A/250V
AC IN
St-by 5.2V (5A)
12V (2A)
16.5V (1.3A)
P401-P402 950V / 135mA
MODEL PLHL-T715A
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42LG60
42LG60 POWER SUPPLY
TURN ON COMMANDS FROM MAIN PWB
POWER SUPPLY (SMPS)
In Stand-By Primary
Side is 178V
In Run it is 380V
BALLAST SECTION
Drive Sig
Bridge
Rectifyer
AC Det
Circuit
6
Stand
By 5V Reg
Inverter
On
12V/24V
Regulators
8
1.2Kv
45Khz
1.2Kv
Ballast
Driver FETs
160V/380V
Regulators
AC In
1
6
Inverter On
Starts the Ballast
Drive Signal
Manipulates
Backlights
Backlights
turn On
9
11
P-DIM
AC
Det
At point 4 TV is in
Stand-By state.
Energy Star compliant.
Less than 1 Watt
Stand
By 5V
12V 16V
DC Up, Backlight brightness Up
11
Inv
On
PWR
2
3
6
Other
Regs
3.3V
Other Circuits
+5V
General 6
5V Reg
6
2
Releases Reset
Microprocessor
Main Board
4
6
8
16V
Audio
12V Video
Processing
Microprocessor
IC407
7
Intelligent Sensor feedback
LVDS
Cables
Tru-Motion
Video
Processing Video 10
BCM IC100
12V
Video
12V
10
LVDS
12V
MAIN PWB
8
P-DIM
LVDS
Cables
Other Circuits
Relay On (PWR)
3.3V Reg
for Micon
6
A-DIM
Fixed
Cust Menu for Backlight
11
Picture Content
7
Video Mute
Is Released
7
Inv On/Off
LVDS Panel Control
Ft Control
5
Reset Circuit
3.3V
PG 24
TFT Controler
Section
12V
7
To
Panel
LD1
(Blue LED)
Blue LED lights to assist
Backlight Lamp Firing
Then goes off.
Remote or Key
Power On
42LG60 P801 ON MAIN PWB TO SMPS
16V
SMPS PWB
P2
ERR
ACD
PWR
INV
ADIM
PDIM
SEL
SYNC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
ERROR
AC DET
PWR
STV
ADM
PDS
SEL
SYNC
C813
10uF
P801
16V
16V
Gnd
Gnd
12V
12V
Gnd
Gnd
5V
5V
5V
5V
Gnd
Gnd
Gnd
Gnd
3.3V
4.57V
2.86V
3.29V
1.68V
3.38V
3.2V
0V
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
PDS (PWM Dimming) Manipulates the
Backlight Brightness via Customer’s OSD.
Manipulates the Backlight Brightness via the
BCM Chip Video content . Darker Picture,
Darker Backlights to facilitate improved
Contrast Ratio. Also the Intelligent Sensor
0.9V ~ 3.2V Range
VBR-B, P-DIM all the same meaning
ADM (Analog Dimming not used)
VBR-A, ADIM all the same meaning
12V
MAIN PWB
C852
0.1uF
C895
0.1uF
C851
100uF
SBY5V
C846
100uF
C897
0.1uF
3.3VST Micon
5V MNT
0
C845
1uF
R832
R7028
C848
0.1uF
4.7K
3.3K
R462
6.8K
AC DET
R488
30K
22
R838
C847
0.1uF
RL ON
R485
0
R834
100
INV ON/OFF
0
R831
0
C844
0.1uF
R860
C880
10uF
0.9V ~ 3.2V
25
P4.2/AD2
29
P7.0/
HBLANK
30
P5.7/
CLK02
31
P5.6
BCMPWM_VBR-A
R174
22
L29
GPI0_27
IC100
BCM
R859
C878
10uF
R487
39
1K
6.8K This Output Value is Fixed
0
C843
0.1uF
IC407
uP
R465
R458
BCMPWM_VBR-B
R175
22
J34
GPI0_28
Power Supply
Backlight Drive
Signal Effects
PWMDIM
manipulates
the Burst
Triangle
Oscillator in
the ballast
drive IC.
ADIM also
manipulates
the Burst
Triangle
Oscillator
But it is not
used.
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42LG60
Power Supply PWB Test (1ST Test All But Backlights)
P2 Connector disconnected from the Main PWB
AC: Not applied when adding jumpers. Applied when making test.
The Power Supply “MUST” be producing STAND-BY +5V and AC Det.
(1) Short either pin 9, 10, 11 or 12 (5V) to Pin 19 (PWR) using a 10K resistor.
(2) Apply AC to the PWB.
This turns on the power supply except for the Ballast Section.
Check the following:
Pins 1 and 2 for +16V
Pins 5 and 6 for +12V
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42LG60
Power Supply PWB Test (2nd Test All Including Backlights)
P2 Connector disconnected from the Main PWB. Apply AC after adding jumpers.
If the 1st test was successful, continue. Leave original 10K in place.
(2): Test the Backlights, jump Pin 19 (PWR) to Pin 20 (INV) and apply AC Power to the PWB.
Observe the Backlights. If normal, the backlights should turn on and off 4 times then go off.
If only ½ the backlights light, (Right side or Left Side), confirm connectors are OK. Check
Transformer Left and Right center pins for signal. If OK, panel defective, backlight failure. If
pulse is missing on one side (L or R Center) of the transformer, power supply defective.
If no backlight activity, confirm the Fuse F700 has approx. 300V on both sides.
If only on one side, check fuse for open. If no 300V, replace Power Supply.
If 300V DC is present, observe the L and R center legs on the left hand side of ballast
transformer T701. Look for 58Khz pulse at 8.7V p/p. If yes, confirm connectors to backlight
OK. If OK, then panel is defective. If no pulse is found, replace the Power Supply.
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42LG60
Power Supply Ballast Board Field Issue
Back Side of Power Supply PWB
T701
Long leads from T701 are arcing through the insulator to ground
Mounting Tabs may be bent
T701
29
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42LG60
Power Supply Connector P2 Odd Pins Voltage and Resistance
P2 Odd "SMPS" to P801 "Main PWB"
Not Used
Not Used
Pin
Label
STBY
Run
Diode Check
1
16V
0V
16V
0.94V
3
Gnd
Gnd
Gnd
0V
5
12V
0V
11.8V
1.32V
7
Gnd
Gnd
Gnd
0V
9
5V
5V
5.15V
1.49V
11
5V
5V
5.15V
1.49V
13
Gnd
Gnd
Gnd
0V
15
Gnd
Gnd
Gnd
0V
17
ERR
3.19V
3.3V
OL
19
PWR
0V
2.86V
OL
21
ADIM
0.1V
1.68V
OL
23
SEL
0V
3.2V
OL
Resistance taken in Diode Mode with Connectors Removed
30
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42LG60
Power Supply Connector P2 Even Pins Voltage and Resistance
P2 Even "SMPS" to P801 "Main PWB"
Not Used
Pin
Label
STBY
Run
Diode Check
2
16V
0V
16V
0.94V
4
Gnd
Gnd
Gnd
0V
6
12V
0V
11.8V
1.32V
8
Gnd
Gnd
Gnd
0V
10
5V
5.15V
5.15V
1.49V
12
5V
5.15V
5.15V
1.49V
14
Gnd
Gnd
Gnd
0V
16
Gnd
Gnd
Gnd
0V
18
ACD
4V
4.57V
1.85V
20
INV
0V
3.29V
OL
22
PDIM
0V
3.38V
OL
24
SYNC
0V
0V
OL
PDIM Pin 22 can vary
according to OSD Backlight
setting. 0.9V 0% to 3.3V
100%
Resistance taken in Diode Mode with Connectors Removed
31
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42LG60
SMPS PWB Connector P401 or P402 Voltage and Resistance
P401 or P402 Backlights
Pin
STBY
Run
Diode Check
1
0V
>1Kvac
0V
2
0V
>1Kvac
0V
Caution: AC over 1Kv. Use extreme caution when reading this voltage.
Operating Frequency 54Khz.
Pins 1 and 2 are actually shorted together. (Either Plug)
Reading between P401 and P402 actually reads the Transformer T701 windings. (0.1V)
For a simple and safe test:
Place the Oscilloscope Probe along side the wire from P401 and P402 connectors
to the Ballast and a 17.5μ sec sine waveform should be measured this would be
an indication that the ballast supply is functioning.
Resistance taken in Diode Mode with Connectors Removed
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42LG60
TRUMOTION PWB SECTION
The Control PWB contains the MICRONAS chip IC101.
This IC is a Full-HD Rate Converter with Motion Blur Removal and Film DeJuddering for 1080p 100/120 Hz LCD panels.
•Vector Based Motion Compensation with Frame Rate Conversion
(eliminates the need for 3:2 Pull Down)
•Dual 10 bit LVDS input
•Quadruple 12 bit LVDS output
Motion Blur Removal increases the video frames by Interpolating a new
image frame between each original frame (Motion Estimated Data Insertion) MEDI.
Juddering is a phenomenon which appears on film based programming
due to the 24 frames per second system used for recording, the picture
develops visual artifacts when converted to 60 frames per second. 3:2 Pull
Down was developed to eliminate this problem. Frame Rate Conversion (Real
Cinema) eliminates the need for 3:2 Pull Down.
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42LG60
TruMotion 120Hz ( Vector Based Motion Compensation)
TruMotion 120 Hz can reduce blurring on fast moving scenes. TruMotion carefully
analyses the picture signal by using advanced algorithms to automatically calculate
a new image frame between each original frame (MEDI).
Conventional
34
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42LG60
24P Real Cinema
Frame Rate Conversion eliminates the need for 3:2 Pull Down Conversion
35
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42LG60
TruMotion PWB (With Shield)
36
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42LG60
TruMotion PWB Removing the LVDS Cable
Disconnect P101, P103 and P104 LVDS Cables
CAUTION: When removing LVDS Cables, be careful.
Press the release Tabs to avoid damage to PWB or to the Cable itself.
LVDS Connectors
Press in from the sides and lift out.
37
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42LG60
TruMotion PWB (Layout with Shield Removed)
X101
IC108
IC109
IC110
38
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42LG60
TruMotion PWB Regulators Identified and Voltages
(1)
(1)
(1)
IC108
IC109
IC110
5 (1.2V)
4 (1.3V)
3 (0V)
2 (3.37V)
1 (3.29V)
5 (0V)
4 (1.79V)
3 (0V)
2 (3.36V)
1 (3.29V)
5 (2.5V)
4 (0V)
3 (0V)
2 (3.3V)
1 (3.37V)
39
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42LG60
TruMotion PWB Crystal X101 Check
1.7Vp/p
20.25Mhz
Only when set is on
Control PWB
X101 Location
40
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42LG60
T-CON (TFT DRIVE) PWB SECTION
LCD Controller Board
The T Con IC UC1 receives from the Control Board at CN1 and CN2 Quadruple 12 Bit
LVDS Signals which it processes into TFT Drive Signals which through connectors
CN4 and CN5 control the LCD Panel. IC’s U15 and U16 are “Dynamic Ram IC’s which
are High Speed Storage Devices used to store the data until it is time to be addressed.
12V is supplied to the T Con Board on connector CN1 from the Control Board
( easily measured at fuse F1). Diode LD1 is a boot up indicator and is helpful in
troubleshooting as a quick indication of a loss of supply and or a Boot Up problem.
LG Philips LCD Drive IC
U15
UC1
U16
Next Slide
gives greater
layout details
F1
41
T CON IC TL22970D
LCD DV
42LG60
T-CON (TFT Drive) PWB (Shield Removed) p/n EAT56803901
To TFT Panel
To TFT Panel
CN5
CN4
US1
UC1
U15
U16
Remember to replace
screws for ground
purposes if turning on the
set.
F1
CN1
CN2
LD1
To
Control
42
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42LG60
T-CON (TFT DRIVE) PWB CHECKS
Check the Regulator
US1 for Correct Voltage
0V
US1
1.8V
3.2V
T-CON PWB
LD1
F1
CN1
Check Fuse
F1 for 12V
Power Off
Anode 0V
Cathode 0V
LED OFF
43
Use LD1 to determine if
The boot up sequence of
The T-CON is OK.
This LED will turn bright Blue
Shortly after power is applied
then go out shortly after
backlights illuminate if all is OK.
Power 1st On
Anode 11.6V
Cathode 0V
LED ON
Power On
Anode 11.6V
Cathode 9.5V
LED OFF
LCD DV
42LG60
MAIN PWB SECTION
Input Signal Processing
The Broadcom or BCM IC100 is the main signal processing IC. and is responsible for :
• ATSC, NTSC, and QAM
• RS 232 service only Port
• Wired Remote Port
• (2) Component Inputs Y, Pr, Pb and Audio L R
• (3) HDMI Inputs (back) (1) HDMI (Side Input)
• RGB PC
• USB (Side Input)
• AV Composite
• SIF and SAP
Output Signals
• Dual 10 Bit LVDS to the Control Board
• Audio output signals to the Speakers
• Digital Audio Output Coaxial and Optical
• ON OFF Control
44
LCD DV
42LG60
Main PWB Layout
Troubleshooting
42LG60
VIDEO PROCESSOR IC100 RUNS HOT, THIS IS NORMAL.
LD803 3.3V-BCM OK
LD803
1
16
If odd Video problems are found, use some freeze spray about IC100 and its circuits,
If video returns to normal, PWB needs to be replaced.
45
LCD DV
42LG60
Main PWB (Back View) Regulator Layout
IC400
1
2
3
SBY
0.4V
0V
0.4V
RUN
3.37V
0V
3.39V
IC805
BCM Reset
IC100 Video
Processor
1
2
3
4
5
SBY
0.V
0V
0V
0.4V
0.1V
RUN
3.3V
5V
0V
3.39V
1.2V
3.3V BCM
IC400
LVDS 12V Switch
Output 5~8 (12V)
Q902
Q901
LVDS 12V Switch Control
IC805
IC802
IC101
IC405
IC810
IC405
1
2
3
SBY
3.29V
0V
0.6V
RUN
3.31V
0V
0.6V
IC802
1
2
3
SBY RUN
0V
5V
0.3V 3.3V
0V
0V
46
IC810
1
2
3
SBY
0V
0V
0.3V
LCD DV
RUN
0V
1.8V
3.31V
42LG60
Main PWB X400 and X200 Check
Video Processor
Crystal
X200
780mVp/p
54Mhz
Only when set is on
Main PWB
X200 Location
Use left
side of
L206
X400
2.4Vp/p
24Mhz
MAIN
PWB
Main PWB
X400 Location
Set on or off
Microprocessor Crystal
47
LCD DV
42LG60
Main PWB LD803 Check
LD803
MAIN
PWB
Main PWB
LD803 Location
Use LD803 as a visual aid.
This lets you know if the +5V is being
converted to 3.3V for the BCM chip IC100.
If LD803 is illuminated, +3.3V is OK.
Note: Only ½ of the dual LED is used.
48
LCD DV
42LG60
Main PWB Tuner Video and SIF Output Check Pin Location
For Easy Access, pop the shield off the tuner
Pin 14
Pin 16
Pin 16 Composite Video
Pin 14 Audio SIF
Pin 1
If you leave the shield on you can
still access the same pins.
Be careful not to accidentally
ground out your test lead on the
shield.
(Note: This is a picture from a
different model, but the concept is
the same)
Pin 3 Tuner B+ (5V)
49
LCD DV
42LG60
Main PWB Tuner Video and SIF Output Check
USING SMTE COLOR BAR SIGNAL INPUT
Pin 14
“SIF”
Signal
850mVp/p 20nSec rate
Pin 16
“Video”
Signal
MAIN
PWB
1Vp/p 20uSec rate
Tuner Location
50
LCD DV
42LG60
Main PWB LVDS P900 Output Check
To confirm that the Main PWB is outputting Picture Content signals, check P900 (LVDS)
cable for output. Check 11-22 and 27-38. This signals vary from each other, but looking for
signals like the ones shown below on any of these pins will confirm the output of video
content. This signal is using standard SMTE Color Bar output from a generator as the input
source.
Pin 11
P900
Location
MAIN PWB
This is just a sample
of two pins on the LVDS.
There are 24 pins carrying video.
Pin 16
51
LCD DV
42LG60
Main PWB Connector P801 Odd Pins Voltage and Resistance
P801 CONNECTOR "Main" Odd Pins to P2 "SMPS PWB"
Pin
Label
STBY
Run
Diode Check
1
16V
0V
16V
OL
3
Gnd
Gnd
Gnd
Gnd
5
12V
0V
11.8V
3V
7
Gnd
Gnd
Gnd
Gnd
9
5V
5V
5.15V
1.47V
11
5V
5V
5.15V
1.47V
13
Gnd
Gnd
Gnd
Gnd
15
Gnd
Gnd
Gnd
Gnd
17
ERR
3.19V
3.3V
2.89V
19
PWR
0V
2.86V
1.1V
21
ADM
0.1V
1.68V
OL
23
SEL
0V
3.2V
OL
Resistance taken in Diode Mode with Connectors Removed
Pin 17 ERR is not used.
Pin 21 ADIM is a fixed voltage.
Pin 23 SEL is not used.
52
LCD DV
42LG60
Main PWB Connector P801 Even Pins Voltage and Resistance
P801 CONNECTOR "Main" Even Pins to P2 "SMPS PWB"
Pin
Label
STBY
Run
Diode Check
2
16V
0V
16V
OL
4
Gnd
Gnd
Gnd
Gnd
6
12V
0V
11.8V
3V
8
Gnd
Gnd
Gnd
Gnd
10
5V
5.15V
5.15V
1.47V
12
5V
5.15V
5.15V
1.47V
14
Gnd
Gnd
Gnd
Gnd
16
Gnd
Gnd
Gnd
Gnd
18
AC Det
4V
4.57V
OL
20
STV
0V
3.29V
1.8V
22
PDS
0V
3.38V
OL
24
SYNC
0V
0V
OL
Pin 22 PDIM can vary according to OSD Backlight setting. 0.9V 0% to 3.3V 100%
Pin 24 is not used
Resistance taken in Diode Mode with Connectors Removed
53
LCD DV
42LG60
Main PWB Connector P401 Voltage and Resistance
P401 CONNECTOR "MAIN PWB" to "Front PWB Assy"
Pin
LABEL
STBY
Run
Diode Check
1
EYEQ-SCL
3.25V
3.25V
2.26V
2
EYEQ-SDA
3.25V
3.25V
2.26V
3
Gnd
0V
0V
Gnd
4
Gnd
0V
0V
Gnd
5
Key1
3.3V
3.3V
1.85V
6
Key2
3.3V
3.3V
1.85V
7
3.3V
3.3V
3.3V
0.71V
8
5V
5V
5V
1.47V
9
EYEQ-Reset
0V
0V
Gnd
10
IR
3.92V
3.92V
1.35V
11
SPKN
0V
0V
OL
12
Gnd
0V
0V
Gnd
13
SPKP
0V
0V
OL
14
n/c
0V
0V
OL
15
Gnd
0V
0V
Gnd
Resistance taken in Diode Mode with Connectors Removed
54
LCD DV
42LG60
Main PWB Connector P800 and P501 Voltage and Resistance
P800 CONNECTOR "Main" Odd Pins to P102 "Control PWB"
Pin
SBY
Run
Diode Check
1
0V
5V
0.8V
2
0V
5V
0.8V
P501 CONNECTOR "Main" to "Speakers"
3
0V
0V
Gnd
Pin
SBY
Run
Diode Check
4
0.5V
3.3V
0.55V
1
0V
8V
2.58V
5
0V
0V
Gnd
2
0V
8V
2.58V
6
0V
16V
OL
3
0V
8V
2.58V
7
0V
16V
OL
4
0V
8V
2.58V
8
0V
0V
Gnd
9
3.3V
3.3V
1.39V
10
3.3V
3.3V
1.28V
11
3.3V
3.3V
1.24V
12
3.3V
3.3V
1.29V
13
3.3V
0V
1.35V
Use speaker out to test for
defective Audio Amp
IC501
Resistance taken in Diode Mode with Connectors Removed
55
LCD DV
42LG60
Main PWB Connector P900 “Odd Pins” Voltage and Resistance
Switched LVDS 12V
SCL
Video Signal Pins
n/c
Video Signal Pins
n/c
Pin
SBY
Run
Diode Check
1
0V
11.7V
OL
3
0V
11.7V
OL
5
0V
0V
Gnd
7
0V
0V
Gnd
9
0.47V
3.3V
1V
11
0V
1.14V
1V
13
0V
1.11V
1V
15
0V
1.12V
1V
17
0V
1.11V
1V
19
0V
1.16V
1V
21
0V
1.14V
1V
23
0V
0V
OL
25
0.5V
3.15V
2.98V
27
0V
1.14V
1V
29
0V
1.12V
1V
31
0V
1.14V
1V
33
0V
1.07V
1V
35
0V
1.16V
1V
37
0V
1.16V
1V
39
0V
0V
OL
56
P900 CONNECTOR
"Main" Odd Pins to P104
"Control PWB"
Resistance taken in Diode
Mode with Connectors
Removed
LCD DV
42LG60
Main PWB Connector P900 “Even Pins” Voltage and Resistance
Switched LVDS 12V
SDA
Video Signal Pins
FRC Reset
Video Signal Pins
Resistance taken in Diode Mode
with Connectors Removed
Pin
SBY
Run
Diode Check
2
0V
11.7V
OL
4
0V
11.7V
OL
6
0V
0V
Gnd
8
0V
0V
Gnd
10
0V
3.3V
1V
12
0V
1.14V
1V
14
0V
1.11V
1V
16
0V
1.05V
1V
18
0V
1.11V
1V
20
0V
1.07V
1V
22
0V
1.05V
1V
24
0V
3.25V
1.28v
26
0V
3.3V
3V
28
0V
1.14V
1V
30
0V
1.09V
1V
32
0V
1.07V
1V
34
0V
1.13V
1V
36
0V
1.07V
1V
38
0V
1.07V
1V
40
0V
0V
Gnd
57
P900 CONNECTOR
"Main" Even Pins to P104
"Control PWB"
Resistance taken in
Diode Mode with
Connectors Removed
LCD DV
42LG60
FRONT TOUCH AND LED PWB SECTION
J1
Front PWB
Assembly
To Main
58
LCD DV
42LG60
Front Touch LED Connector J1 Voltage and Resistance
J1 CONNECTOR “Ft LED Touch" to J2 “Ft Control PWB"
Pin
STBY
Run
1
3.3V
3.3V
2
3.3V
3.3V
3
5V
5V
4
0V
0V
5
0V
0V
6
0V
0V
7
3.3V
3.3V
8
0V
0V
9
3.3V
3.3V
With all Connectors Removed, no ground return.
59
LCD DV
42LG60
Front PWB Assembly Layout
Right Tweeter
The Intelligent Sensor
and IR Sensor are
located on the front of
this PWB
J2
To Front Touch
LED PWB
J1
To Main PWB
Light Diffuser for the
Intelligent Sensor
To Side Key
Control PWB
J3
IR Sensor
60
LCD DV
42LG60
Front Control Connector J1 Voltage and Resistance
J1 CONNECTOR "Front Control PWB" to "MAIN PWB" P401
Pin
LABEL
STBY
Run
1
EYEQ-SCL
3.25V
3.25V
2
EYEQ-SDA
3.25V
3.25V
3
Gnd
0V
0V
4
Gnd
0V
0V
5
Key1
3.3V
3.3V
6
Key2
3.3V
3.3V
7
3.3V
3.3V
3.3V
8
5V
5V
5V
9
EYEQ-Reset
0V
0V
10
IR
3.92V
3.92V
11
SPKN
0V
0V
12
Gnd
0V
0V
13
SPKP
0V
0V
14
n/c
0V
0V
15
Gnd
0V
0V
61
With all Connectors
Removed, no ground return.
LCD DV
42LG60
Front Control Connector J2 Voltage and Resistance
J2 CONNECTOR “Ft Control” to “Ft Touch LED" J1
Pin
STBY
Run
1
3.3V
3.3V
2
3.3V
3.3V
3
5V
5V
4
0V
0V
5
0V
0V
6
0V
0V
7
3.3V
3.3V
8
0V
0V
9
3.3V
3.3V
J3 CONNECTOR “Ft Control” to “Side Controls" P100
Pin
STBY
Run
1
3.3V
3.3V
2
0V
0V
3
3.3V
3.3V
4
0V
0V
With all Connectors Removed, no ground return.
62
LCD DV
42LG60
SIDE KEYBOARD (FUNCTION KEYS) SECTION
P100
To Front
Control PWB
63
LCD DV
42LG60
Side Control Connector P100 Voltage and Resistance
P100 CONNECTOR “Side Control” to “Front Control" J3
Pin
STBY
Run
1
3.3V
3.3V
2
0V
0V
3
3.3V
3.3V
4
0V
0V
With all Connectors Removed, no ground return.
64
LCD DV
42LG60
INVISIBLE SPEAKER SECTION
Right
Tweeter
Left
Tweeter
Right
Speaker Box
Left
Speaker Box
65
LCD DV
42LG60
Speaker Box Assembly Removed
Speaker Box
Removed
To
Tweeters
To Remove Speaker Box, remove the 4 screws show in circles remove wire harness.
Carefully disconnect both Tweeters. Unplug P500 from Main PWB.
66
LCD DV
42LG60
DISASSEMBLY SECTION
This section of the manual
will discuss Disassembly,
Layout and Circuit
Board Identification, of the
42LG60 LCD Direct View
Television.
Upon completion of this section the Technician will have a
better understanding of the disassembly procedures, the layout
of the printed circuit boards and be able to identify each board.
67
LCD DV
42LG60
Power Supply PWB Removal
Disconnect P2, AC In, P402 and P402
Remove the 6 screws indicated below in red.
68
LCD DV
42LG60
MAIN PWB Removal
Disconnect P401, P501, P800, P801 and P900
Note: In the bottom right is a connector P200. This is an open connection.
Remove the 2 screws securing the Side input decorative plastic piece on the right.
Remove the 6 screws securing the Main PWB indicated below in red.
The Main PWB can also be lifted off the mounting frame by;
Disconnect P401 and P501.
Remove the 1 screw securing the top mounting frame. Swing the PWB away.
69
LCD DV
42LG60
TruMotion PWB Removal
LVDS Cables
Press in from sides
to release
Disconnect P101, P102 P103 and P104
Remove the 4 screws indicated below in red.
70
LCD DV
42LG60
T-CON (TFT Drive) PWB Removal
Disconnect CN1, CN2, CN3 and CN4
Remove the 3 screws indicated below in red.
71
LCD DV
42LG60
11 X 17 FOLDOUT SECTION
This section shows the 11X17 foldout that’s available in the Paper
and Adobe version of the Training Manual.
The Adobe version of this Training Manual allows the viewer to
zoom in and out making reading of the small text easier.
This Power Point shows a graphical representation of the 11 X 17
foldout page so clarity is limited.
72
LCD DV
42LG60
42LG60 CIRCUIT INTERCONNECT DIAGRAM
TFT PANEL
LD1 Blue LED TFT Drive PWB Check
SET 0FF
LED OFF
Anode 0V
Cathode0V
BOOT OK
LED ON
Anode 11.6V
Cathode 0V
US1
SET ON
LED OFF
Anode 11.6V
Cathode 9.5V
0V
3.2V
CN5
U15
The appearance of LD1 when the set is on appears to be lit dimly.
However there is a small hole in the back panel frame and the
T-CON PWB that allows the backlight to make it appear lit.
1.8V
FRONT SIDE OF MAIN PWB
CN4
LD1
UC1
U16
TFT-Drive (T-CON)
P2 "SMPS" to P801 "Main PWB"
Odd Pins
Label
STBY
Run
Pin
Label
16V
0V
16V
2
16V
Gnd
Gnd
Gnd
4
Gnd
12V
0V
11.8V
6
12V
Gnd
Gnd
Gnd
8
Gnd
5V
5V
5.15V
10
5V
12
5V
5V
5V
5.15V
14
Gnd
Gnd
Gnd
Gnd
16
Gnd
Gnd
Gnd
Gnd
18
ACD
ERR
3.19V
3.3V
20
INV
PWR
0V
2.86V
22
*PDIM
ADIM
0.1V
1.68V
24
SYNC
SEL
0V
3.2V
Pin
1
3
5
7
9
11
13
15
17
19
21
23
Left
Backlight
Plug
CN1
STBY
0V
Gnd
0V
Gnd
5.15V
5.15V
Gnd
Gnd
4V
0V
0V
0V
Run
16V
Gnd
11.8V
Gnd
5.15V
5.15V
Gnd
Gnd
4.57V
3.29V
3.38V
0V
Pins 17, 23 and 24
Not Used
1
4
3
6
5
8
7
10
9
12 11
14 13
16 15
10K
18 17
20 19
22 21
24 23
IC802 (On Back)
3.3V Regulator
Function Pin
Volts
1 0V
Gnd
Out
2 3.3V
In
3 5V
n/c
Gnd
IC805 (On Back)
3.3V Switching Regulator A3.3V-BCM
4
5
0.0V
0.0V
Use L801 left side to test output
Use any top pin of IC807 to test input
IC806
IC820
1.2V Switching Regulator A1.2V-BCM
9V Regulator
Function
Pin Volts Function
Pin
Volts
Name
In (+12V)
1 11.6V In
6,7,8,10 5V
Gnd
Out
2
3
0.0V
9V
Out
On/Off
IC404
3.3V Regulator
LVDS
Function
Gnd
Pin 21 is a
Fixed Voltage
Out
In
1,2,3,4,5 1.2V
17
Pin Volts
1 0V
2
3
3.3V
5V
P103
X101
20.25Mhz
IC103
1st” short either pin 9, 10, 11 or 12 (5V) to Pin 19 (PWR) using a 10K resistor.
This turns on the power supply.
2nd: To test the Backlights, jump Pin 20 (INV) to Pin 19 (PWR)
Observe the Backlights.
If normal, the backlights should turn on and off 4 times. Then they go off.
If only ½ the backlights light, (Right side or Left Side), confirm connectors are OK.
If yes, panel defective.
If no backlight activity, confirm the Fuse F700 has approx. 300V on both sides.
If on one side, check fuse for open.
If no 300V, replace Power Supply.
If 300V present, observe the center leg on the left hand side of ballast transformer
T701. Look for 45Khz pulse at 8.7V p/p.
If yes, confirm connectors to backlight OK, if OK, then panel defective.
If no pulse, replace the Power Supply.
Scope
test point
Backlight pulse over
1000V p/p (45KhZ)
P402
Ballast
Section
POWER SUPPY
F700
5A 250V
335V
P401
Side Control Keys
P100
P2
F101
8A 250V
AC
AC In
F700 90V in Stand-By
Function Pin
In
3
Out
Gnd
Pin
3
Volts
5V
Name
ST_+5V
2
1
3.3V
0V
Reset
Gnd
2
1
B
E
Volts
ST-5V
RL-ON (PWR)
0V
Pin
1
2
3
Volts
3.3VST-MICOM
0.0V
Low to High to B Q400
Q902 (On Back)
12V LVDS control to Q901
Function
Source
1.8V (+1.8V-NTP)
0V
Control
Gnd
Pin
C
Volts
12V
B
E
LVDS-Panel-Control
0V
Q901 (On Back)
12V LVDS On control to P900 Pins 1~4
Q802 (On Back)
5V Switch control to Q801
Control
Gnd
P101
Function
In
Gnd
Out
Volts
3.3V from IC802
Function Pin
In
C ST-5V
P104
Volts
RL-ON (PWR)
0V
Function
Source
Pin
1, 3
12V
Volts
Control
Output
2, 4
5~8
Low from Q902
12V
LVDS
IC101
TRU-MOTION
P102
Right
Backlight
Plug
Tuner Pin 16 SMTE Color bar In
IC108 IC109 IC110
IC109
IC108
5 (0V)
5 (1.2V)
4 (1.79V)
4 (1.3V)
3 (0V)
3 (0V)
2 (3.37V) 2 (3.36V)
1 (3.29V) 1 (3.29V)
IC110
5 (2.5V)
4 (0V)
3 (0V)
2 (3.3V)
1 (3.37V)
See back side of page for Waveforms for
P900 using SMTE Color bar as the Input.
MAIN PWB
Pin 24
Pin 23
Function Pin
Volts
In
2 5V
Out
4
3.3V (A3.3V-BCM)
On/Off
1
Power Control-3.3V
Pin
C
B
E
IC405 uP Reset (On Back)
Reset by Charge of C431
IC810 (On Back)
IC404 uP 3.3V
3.3VST-MICOM
Function
In
Q801 (On Back)
5V Switch
Function
Source
Control
Gnd
Power Control 1.8V Switching Regulator +1.8V-NTP
Use L014 left side to test output
Use any top pin of IC820 to test input
Out
Gnd
IC102
P2
CN2
3A 125V
11.6V
PDIM Pin 22 can vary according to OSD Backlight
setting. 0.9V 0% to 3.3V 100%
2
F1
BACK SIDE OF MAIN PWB
IC800
IC807
5V Switching Regulator
2.6V Switching Regulator A2.6V-BCM
Function
Pin Volts Function Pin
Volts
Name
In from IC806 1 8.95V In
6,7,8,10 5V
On/Off
2 3.3V
Out
1,2,3,4,5 2.6V
Power Control
Out (+5V-TU) 3 5.0V
On/Off
17
IC600
P801
Tweeter
Spk
Tweeter
Ft. PWB
Assy. J1
J2
J3
IC503
IC701
LG
J1
Ft. TOUCH
LED/Push Sw
IC500
Pin 1 ~ 16
TUNER
5V Pin 3
Video Pin 16
Audio SIF Pin 14
1
16
TUNER
ATSC/QAM/
NTSC
IC900
IC806
IC800
P501
IC302
IC100
BCM
*IC805
*IC802
X200 (54Mhz)
*IC810
IC501
IC807
IC1201
P900
P800
*Q902 *Q901
LD803
3.3V BCM *IC400
Reset
IC805
BCM
OK LED
IC402
Spk
IC820
IC300
IC1200
IC303
IC202
IC301
24Mhz
X400
IC1000
P401
IC304
IC404
Q400
E
B
uP
IC407 *IC405
P200
Not Used
*Grayed out components on the back
LVDS CABLE P900 FROM MAIN PWB TO CONTROL
PWB P101 USING SMTP COLOR BAR INPUT
LAST TWO WAVEFORMS ARE FROM THE TUNER
Measurements +/- 5%
42LG60
Conclusion
This concludes the
42LG60
training package
presentation.