1080p direct view lcd training 42lh90
TRANSCRIPT
42LH90 42LH90
LED Backlights
1080PDirect View LCD
Training
Original February 09, 2010Updated July 28, 2010
LCD DV 42LH902 February 2010
OUTLINEOUTLINE
• Main Board
• Switch Mode Power Supply
Preliminary Section:
Troubleshooting Section: Board Operation Troubleshooting of :
Contact Information, Preliminary Matters, Specifications,LCD Overview, General Troubleshooting Steps, Signal Distribution, Disassembly Instructions and Voltages
• Ft Control Board
• T-CON (TFT Controller) Panel Driver board
• Side Keys
• Inverter Board (LED Backlight Driver)
• Speakers
Disassembly Section: Removal of Circuit Boards
LCD DV 42LH903 February 2010
42LH90 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.
Overview of Topics to be DiscussedOverview of Topics to be Discussed
LCD DV 42LH904 February 2010
IMPORTANT SAFETY NOTICEIMPORTANT 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.
CAUTIONCAUTION
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.
Preliminary Matters (The Fine Print)Preliminary Matters (The Fine Print)
LCD DV 42LH905 February 2010
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 InformationRegulatory 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.
ESD NoticeESD Notice (Electrostatic Static Discharge)(Electrostatic Static Discharge)
LCD DV 42LH906 February 2010
Customer Service (and Part Sales) (800) 243-0000
Technical Support (and Part Sales) (800) 847-7597
USA Website (GSFS) http://gsfs-america.lge.com
Customer Service Website us.lgservice.com
LG Web Training lge.webex.com
LG CS Academy lgcsacademy.com
Published February 2010 by LG Technical Support and TrainingLG Electronics Alabama, Inc.
201 James Record Road, Huntsville, AL, 35813.
32LG40, 32LH30, 37LH55, 42LG60, 42LG70, 42LH20, 42LH40, 42LH50, 42LH90, 42SL80, 47LG90, 47LH85, 47LE850042PG20, 42PQ20, 42PQ30, 50PG20, 50PJ350, 50PK750, 50PS80, 50PS60, 60PK750, 60PS11, 60PS60, 60PS80
LCD-DV:
PLASMA:
Also available on the Plasma Page:PDP Panel Alignment Handbook, Schematics with Bookmarks
Plasma Control Board ROM Update (Jig required)
LG Contact InformationLG Contact Information
Presentations with Audio/Video and Screen Marks
New Training Materials on New Training Materials on the Learning Academy sitethe Learning Academy site
http://136.166.4.200
LCD DV 42LH907 February 2010
Safety and Handling Regulations
1. Approximately 20 minute pre-run time is required before making any picture performance adjustments from the Menu.
2. Refer to the Voltage/Current silk screening on the Switch Mode Power Supply.3. C-MOS circuits are sensitive to static electricity.
Use caution when dealing with these IC and circuits.4. Exercise care when making voltage and waveform checks to prevent costly short circuits
from damaging the unit. 5. Be cautious of lost screws and other metal objects to prevent a possible short in the
circuitry.
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…
Checking Points to be Considered
LCD Direct View OverviewLCD Direct View Overview
LCD DV 42LH908 February 2010
Basic Troubleshooting StepsBasic 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.
LCD DV 42LH909 February 2010
This section of the manual will discuss the specifications of the42LH90
LCD Direct View Display
42LH90 PRODUCT INFORMATION SECTION42LH90 PRODUCT INFORMATION SECTION
LCD DV 42LH9010 February 2010
Basic SpecificationsBasic Specifications
Key TV Features• LED Backlight with Local Dimming• TruMotion 240Hz• Intelligent Sensor• Full HD 1080p• 2,000,000:1 Contrast Ratio• 2.4ms Response Time• 500 cd/m² Brightness• Wide Color gamut• Super IPS Panel• XD Engine• 24fps Real Cinema• ISFccc Ready• Picture Wizard• AV Mode II (Cinema, Sports, Game)• NTSC / ATSC / Clear QAM
• Audio Output Power 10W x 2• Invisible Speaker system• Clear Voice II• SRS TruSurround XT™• Smart Volume Controller• Dolby® Digital 5.1 Decoder• Backlight Control• Video Mute• ENERGY STAR® 3.0 Compliant• 4 HDMI™ v1.3 with Deep Color• SIMPLINK™ Connectivity• 2 HD Component Video Inputs• 2 Composite inputs• 1 Digital Audio Out• USB 2.0 (JPEG, MP3, MP4, Divx)• PC Connectivity (D-Sub 15pin)• RF Antenna Input
LCD DV 42LH9011 February 2010
Basic Specifications (LOGO Familiarization)Basic Specifications (LOGO Familiarization)
Full HD 1080p Resolution Displays HDTV programs in full 1920 x 1080p resolution for a more detailed picture.
LCD DV 42LH9012 February 2010
TOP PORTIONBOTTOM PORTION
Remote Control FamiliarizationRemote Control Familiarization p/n MKJ61841701
LCD DV 42LH9013 February 2010
Accessing the Service MenuAccessing the Service Menu
To access the Service Menu.1) You must have the Service
Remote. p/n 105-201M2) Press “In-Start”3) A Password screen appears.
Note: A Password is required to enter the Service Menu.
Enter; 0000
LCD DV 42LH9014 February 2010
TV Rear Input / Output JacksTV Rear Input / Output Jacks
Rear In/Out Jacks
USB PortSoftware Upgrades
Music, Photos
Side In/Out
MAIN BOARDRear and Side
Input/Output locations
LCD DV 42LH9015 February 2010
1) Create an LG_DTV folder on the USB Flash Drive
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.
Software DownloadSoftware DownloadShows the Currently Installed Version
Shows the Software Version
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.
42LH90 Dimensions
7-7/8"200mm
28-3/16"716.28mm
14-1/8"357.98mm
42"1066.8mm
Remove 4 screws to remove stand for
wall mount
16-15/16"430mm
17-7/8"454mm
30-5/8"777.88mm
Center7-7/8"
200mm
9-5/8"244mm
10-5/8"270mm
2-7/16"61.6mm
Weight without Stand: 43 lbWeight with Stand: 51.1 lb
3-11/16"93.98mm
14-3/16"360.68mm
21"533.4mm
14-1/8"357.98mm
16
42LH90 Product Dimensions42LH90 Product Dimensions
There must be at least 4 inches of Clearance on all sides WattageAverage 210WStand By <1W
Model No.Serial No.
Label
LCD DV 42LH9017 February 2010
DISASSEMBLY SECTIONDISASSEMBLY SECTION
Disassembly:This section of the manual will discuss Disassembly, Layout
(Circuit Board Identification) of the 42LH90 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.
LCD DV 42LH9018 February 2010
Remove the 23 screws indicated.Pay attention to the size and type of screw
as there are many different types.Putting in an improper screw when reassembling may Cause damage.
The Stand does not need to be removed before removing the back.
Removing the Back Cover Removing the Back Cover
Bottom two screws do not have to be
removed.
Decorative Plastic Cap (if used) must
be removed.
LCD DV 42LH9019 February 2010
Circuit Board LayoutCircuit Board Layout
POWER SUPPLY
IntelligentSensor / IR
AC Input
Right LEDConnection
Rear Inputs
Power Button
Main Board
Left LEDConnection
Tweeter R
Full Range Speaker R
Tweeter L
Side Keys
MovingLED
LVDS Cables
TFT PanelEAJ60694101
p/n EAY58584001
p/n EBR62151101
p/n EAB58534501 p/n EAB58536001
T-CON boardp/n EAT60665101
Full Range Speaker L
INVERTERp/n EAY60702001
SideInputs
p/n EAD60679428
p/n EAD60679364
T-CON
POWERSUPPLY
MAINBOARD
INVERTER
CN306
P203
P201
SK100SK101
CN1
CN3CN4
CN307 N/C
CN305 N/CCN1 CN2
CN5 CN4
P3500 P3502P3501
P700
P1200P600
Speakers (Front Left)Speakers (Front Right)
AC In
MainPower
IR
LED
KEY B
OA
RD
P100
P101IRP100
P103
J1
42LH90 Connector Identification Diagram42LH90 Connector Identification Diagram
P101N/C
LED
TFT PANEL
20
LCD DV 42LH9021 February 2010
Power Supply Power Supply Board RemovalBoard Removal
Disconnect P201, P203, AC In SK100 and SK101.
P201
PowerSwitch
Press inTwo tabsto release
lock
P201
SK101
SK100
Remove the 6 screws indicated
by the arrows.
AC In
P203
LCD DV 42LH9022 February 2010
Remove the 3 Screws in the T-CONshield and remove the shield
CN5 CN4
Disconnect CN1, CN2, CN4 and CN5.See next slide for details about removing cables.
The two screws shown in the picturebelow are for the Service Position.
They would have been removedwhen removing the shield.Be sure to reinstall them ifservicing the T-CON Board.
CN1 CN2
STEP (1)
STEP (2)
TT--CON Board RemovalCON Board Removal
Note: Chocolate (Heat Sink Material)
LCD DV 42LH9023 February 2010
To remove the LVDS cables CN1 and CN2; Press in on the two tabs and slowly rock the cable out of the connector.
(Shown by the arrows in Figure above)
(CN1) LVDS
Press InPull Out
(CN2) LVDS
Press InPull Out
Press In
TT--CON Board Removal Board Continued (Unlocking CN1 and CN2 LVDS CaCON Board Removal Board Continued (Unlocking CN1 and CN2 LVDS Cables)bles)
Note: The tabs are fragile, use caution, they may break.
LCD DV 42LH9024 February 2010
To remove the flex cables to the TFT Panel, CN4 or CN5, place a soft thin object like a fingernail underneath the black locking tab and gently pull forward.
(Shown by the arrows in Fig 1 and 2)
Fig 1
Fig 3
Unlocked
Flip the lock up and back from the flex cable. Then the flex cable can be easily removed.
The locking tab is flipped down
CN5 or CN4 Locked
Fig 2
TT--CON Board Removal Board Continued (Unlocking CN4 and CN5 LVDS CaCON Board Removal Board Continued (Unlocking CN4 and CN5 LVDS Cables)bles)
LCD DV 42LH9025 February 2010
Removing the Main BoardRemoving the Main Board
Remove any tape holding down any cables.
Remove the 6 screws indicated by the arrows.
P600
P700
Flip the locking tab upward, pull the LVDS ribbon out.
NOTE: Always check on top and behind the Large ICs. And look for a piece
of Chocolate(Heat Transfer Material).
Be sure to transfer to new Board if present.
Disconnect P3500, P3501, P3502, P1200,
P700 and P600P3500 P3502
Press in on the top and bottom release
tabs to remove.
P1200
n/c
n/c
Decorative Plastic
(See a and b)
(a)SlideRight
(b)Lift OutPull
Down
P3501
Remove decorative plastic and remove the
board.
LCD DV 42LH9026 February 2010
Removing the Inverter BoardRemoving the Inverter Board
Remove the 8 screws indicated by the arrows.
Remove the Inverter Shield.
NOTE: Always check for Chocolate(Heat Transfer Material).
Be sure to transfer to new Board if present and replace in the correct position.
There should be 8 pieces on the DC to DC converter coils near the bottom right.
Disconnect CN1, CN3, CN4 and CN306.Remove the Inverter.
CN306
CN4
CN1
CN3
Use caution, do not allow screws to fall.
NOTE: If Servicing the Board, return the screws into the board to provide stability
and grounding.
Inverter
Chocolate
LCD DV 42LH9027 February 2010
Removing the Inverter Board (Chocolate Notice) Back Side of the Removing the Inverter Board (Chocolate Notice) Back Side of the BoardBoard
On the back side of the Inverter are 5 pieces of
Chocolate, (Heat Transfer and Noise reduction pads). Be sure to replace these on the New Inverter if the board
is replaced.
Be sure they do not fall off if the Inverter is removed.
Chocolate
Chocolate Close Up
Chocolate LocationWhite Box Outline
LCD DV 42LH9028 February 2010
Removing Front Boards (IR Board and Moving LED Board)Removing Front Boards (IR Board and Moving LED Board)
P100 IR board / Intelligent Sensor
p/n EBR62128101
Moving LED board(Power LEDs)
p/n EBR61674001
p/n EBR62127501
Key board
Disconnect J1 or P100. Remove the LED board by lifting up on the two locking tabs and pull
backwards on the board.
Disconnect P101 and P102. Note P102 is behind the Power Switch.
Remove the IR board by removing the 1 screw and lift out the board.
P101
P102
J1
The Power Switch has been removed for easier
viewing of connectors and screws.
P100Tab
Tab
LCD DV 42LH9029 February 2010
Removing Front Key BoardRemoving Front Key Board
(A)Push In
p/n EBR62127501
Key Board
To Remove the Key Board, Apply Pressure at
point (A) on the Key Board itself while using an object to slightly pry
out from the top.
Disconnect P100
and remove the Key Board
P100
(B)Push In
Tab
Tab
Apply Pressure at point (B) on the Key Board itself while using an
object to slightly pry out from the bottom.
TabSlots
TabSlots
LCD DV 42LH9030 February 2010
TROUBLESHOOTING SECTIONTROUBLESHOOTING SECTION
Troubleshooting:This section of the manual will also discuss
troubleshooting.
Upon completion of this section the Technician will have a better understanding of how to diagnosis and resolve
problems.
LCD DV 42LH9031 February 2010
POWER SUPPLY SECTIONPOWER SUPPLY SECTION
This switch mode power supply develops Stand By 5V at all times when AC is applied.At power on, it develops 12V and 24V for the Main boardAnd 24V for the Inverter.
This power supply draws a little less that 1 watt during stand by mode. The fuse F101 reads 159.9V (from hot ground) during this time.
When the controller chip (IC501) receives the PWR-ON command via P201 Pin 19, the primary section increases its current supplying ability. The Primary fuse F101 now reads 390V.
P201 Connector: (To Main Board)12V is routed out P201 pins 5 and 6 and 24V is routed out P201 pins 1 and 2.
P203 Connector: (To Inverter Board)24V is routed out P203 pins 1 through 5.
LCD DV 42LH9032 February 2010
There are three types of Main Power switch used in LG televisions.
Type 1: Shuts off AC to the Power Supply.
Type 2: Opens ground to the front IR board. (Stand-By 5V Remains, the Main board stays alive).
This prevents any activity of the IR or the Key Board. When the Switch is opened, a line called Power Key pulls up high when ground opens. When the switch is closed, this same line called Power Key feeds back to the Microprocessor and the Micro. Turns on the Power.
Type 3: Opens ground to the front IR board. (Stand-By 5V turns off, the Main board is dead).
This prevents any activity of the IR or the Key Board. When the Switch is opened, a line called Power Key pulls up high when ground opens. This line feeds back to the Main board and from there it routes to the Power Supply. The high tells the Controller chip to turn off STBY-5V. When the switch is closed, this same line called Power Key now goes high and feeds back to the Power Supply and tells the controller chip to turn STBY-5V on.
Power Supply (Main Power Switch Type 1) LocationPower Supply (Main Power Switch Type 1) Location
On Off
If the TV won’t come on, be sure to check the Main Power Switch before assuming a failure has occurred.
This switch breaks AC to the SMPS.
MAIN POWER SWITCH LOCATIONTYPE 1
(Bottom Left Side viewed from rear)
LCD DV 42LH9033 February 2010
Hot Ground Shock Hazard
AC INSK101
F1005A/250V
AC IN
N
L
To Master Power SwitchSK101
Components Inside the
dashed line are Hot Gnd
F1013.15A/250VRun 390V
STBY 159.8VFrom Hot Gnd
Pin 1
To MainP201
Power Supply (SMPS) Power Supply (SMPS) Board LayoutBoard Layout
F101 (Diode Check)
Red Lead on Fuse (Open)Black Lead on Hot Ground
Black Lead on Fuse (0.608V) Red Lead on Hot Ground
The Left pin on SK101 goes to the Main Power Switch. The Right hand pin returns
from the Main Power Switch.
POWER SUPPLY (SMPS)Inverter On
Starts the InverterLED Drive Signal
24V B+ forInverter
Stand By 5V
Resets the Microprocessor
MAIN BOARD
PWRInvOn
MstarMicroprocessor
IC100(½)
24VRegulator
12V/24V Regulators
Other Regs
StandBy 5V Reg
1
2
5
66
8
8
6
2
4
42LH90 Power Supply Turn On Sequence42LH90 Power Supply Turn On Sequence
5
5
8
In Stand-By Primary side is
160VIn Run (PWR On)
Primary side is390V
3
24V Audio
12V 24V
8
LVDS12V12V
7
T-CON BOARD
7
LVDS Panel Control
Inv On/Off
Other Circuits
A-DIMNot
Used
P-DIM
Manipulates All Backlight LEDs
IC10039V Reg
9
9
INVERTER
Pow
er On/O
ff
Local Dimming Control Signal
Global Dimming
7
34
IC103, Q106
IC702Reg
3.3V_ST
Remote Power ButtonPower On/Off
12V
T-CON DC-to-DC Converter generates
3.3V 16V 26V -5V
10
Inverter On
P-DIM
24V
Inverter On
LocalDimming
Signal
7
11 Video ArrivesAt point TV is in Stand-By state. Energy Star compliant.Less than 1 Watt
3
MstarIC100
(½)
IC3502Dimming
IC
Cust Menu for BacklightPicture Content
Intelligent Sensor
Q706(½)
LVDS
LVDS
To Panel Left
Side LEDs
To Panel Right
Side LEDs
8AC In
Power Supply will not be on if Main
Power Switch is off.
Main (Master)Power SW
OnOff
L
L
2
4
Relay O
n
Q706 (½)5V Switch
IC10025V_TU Reg
PWM-DIM (PWM Dimming) Manipulates the Backlight Brightness via Customer’s OSD.Manipulates the Backlight Brightness via the Video Processor chip. Darker Picture, Darker Backlights to facilitate improved Contrast Ratio. 0.6V ~ 3.3V Range
42LH90 P700 on Main Board to SMPS Turn On Circuit42LH90 P700 on Main Board to SMPS Turn On Circuit
R189
R185100Ω
100
R7141
R704
C71115pF
P700
11.9V
Gnd
Gnd
Gnd
Gnd
0V
3.2V
5V
1.66V
P201
ERR
PWR
A.DIMINV.On
PWM-DIM
n/c
SMPS
AD12
100Ω
n/c
GndGndGndGnd
Analog Dimming (Fixed Value)
100Ω
H5R245100
SBY5V
MAIN BOARD
5.15V
GndGnd
12V
2
1
4
3
6
5
8
7
10
9
11
12
14
13
16
15
18
17
20
19
22
21
23
24
2
1
4
3
6
5
8
7
10
9
11
12
14
13
16
15
18
17
20
19
22
21
23
24
24.1V24V
GndGnd
GndGndGndGnd
n/c n/c
n/c n/c
L706
L70724V
C72247uF
C7281uF
L70412V
C72168uF
L701
R771 R257
G5R719 10KΩQ702
R713 0Ω
R717 3.3KΩ
P5.3R244 100Ω
+5V_General
INV_CTL
3
1
2
6
5
8
7
Q706
+5VL715
12V_TCON (LVDS 12V)
Q703
R757 0Ω
0.2V 0.6V
4Q705
PANEL_CTL
0.6V
12VR739 47KΩ
R740 47KΩ
AB13
Digital Dimming (Variable)
C726220uF
+5V_ST
L700
R760
0L705
RL_ON
PWM0
PWM2
5V_ST
4.7K
C7251uF
C7061uF
24.1V
4.65V
0Ω
35
Q701
L708
5.2V
n/c
n/c
INV ON/OFF
PWR ON
A-DIM
PWM-DIM
R707 4.7K P5.6
Error Out Stby = 0V Run = 0V
Error=5V: Normal 0V:Micro shuts off
television.
IC100Micro
RL_ON
R201 100Ω
31
Power Det H6
ResetD4
Key 1 A4
Key 2 B4
Power On/OffF6
GPIO-09
R70620K
Error Out
5.15V
5.15V
5.15V
11.9V
Q7040V
E5
100ΩR251R726
10KΩ
L728
+5V_GeneralL709
3.3V_STFrom IC702From
IC103,Q106 Reset
LCD DV 42LH9036 February 2010
Power Supply Board Low Voltage Test 1Power Supply Board Low Voltage Test 1
AC Should not be applied at any time while adding resistors or while unplugging connectors as damage to the circuit Board may occur.
a) When AC is applied, the SMPS “MUST” be producing STBY 5V on pins 7, 8, 9 or 10 of P201.
If 5V Standby is not being generated, the SMPS is defective andmust be replaced. There is no need to continue with the next test.But, make sure the Main Power Switch is On.
(b) Unplug P700 on the Main Board to make insertion of the Resistors much easier.
TEST 1:
(1) Add a 100Ω resistor between (5V STBY) pin 7, 8, 9 or 10 and Pin 2 (PWR). Apply AC. This will turn on the power supply.a) Check that the 24V and 12V power supplies are
turned on, • P201 (24V pins 17 and 18) • P201 (12V pins 13 and 14)• P203 (24V pins 1 through 5) to the Inverter.
(2) Remove AC power.Use P700
Side to insertresistors
No Backlights during this test
LCD DV 42LH9037 February 2010
Continue if the 1st test was OK. Leave original resistor in place.
(3) Add another 100Ω resistor between (5V) pin 7, 8, 9 or 10 and Pin 20 (INV On).
(4) Apply AC Power. Simulating a Power and Backlight On command.
Backlights Normal:a) If normal, the backlights should turn on. SMPS OK, Inverter OK.
Backlights Abnormal:a) Recheck all connections.b) Confirm the INV On/Off line pulling up to at least 3V.
REMOVE AC POWER:c) Check the connections to the Inverter.
If the 24V was arriving at the Inverter in Test 1 (pins 1~5 of P203) and the Inverter On command (INV-ON pin 12 of P203) is arriving, then see Inverter Section for further testing.
Power Supply Board Backlights Test 2Power Supply Board Backlights Test 2
P700 Connector disconnected from the Main Board. Apply AC after adding jumper.
Use P700Side to insert
resistors
LCD DV 42LH9038 February 2010
Diode Mode values taken with all Connectors Removed
1.6V5.0V0VPWR2
GndGndGndGnd4
GndGndGndGnd6
Open5.15V5.15V5.2V8
Open5.15V5.15V5.2V10
GndGndGndGnd12
0.98V11.9V0V12V14
GndGndGndGnd16
0.74V24.1V0V24V18
Open4.65V0VINV.ON20
Open0V0VErr Out22
Open3.2V0V2PDIM24
Diode CheckRun STBYLabelPin
P201 Even "SMPS" to P601 "Main"
Openncncnc1
GndGndGndGnd3
GndGndGndGnd5
Open5.15V5.15V5.2V7
Open5.15V5.15V5.2V9
GndGndGndGnd11
0.98V11.9V0V12V13
GndGndGndGnd15
0.74V24.1V0V24V17
Openncncnc19
Open1.66V0.47V1A.DIM21
Openncncnc23
Diode CheckRun STBYLabelPin
P201 Odd "SMPS" to P601 "Main"
1ADIM Pin 21 Fixed and not used 2PDIM Pin 24 can vary according to type of signal being processed and the OSD Backlight setting. 0.33V 0% to 3.3V 100%. Output from the Video Processor IC100.
Power Supply Connector P201 Voltage and Diode CheckPower Supply Connector P201 Voltage and Diode Check
LCD DV 42LH9039 February 2010
Power Supply Connector P203 Voltage and Diode CheckPower Supply Connector P203 Voltage and Diode Check
Diode Mode values taken with all Connectors Removed
0.74V24.0V0V24V1~5GndGndGndGnd6~10Open1.66V0.47V1A.DIM11Open4.65V0VINV_ON13Open3.2V*0V2P-DIM13Open0V0VERR14
Diode CheckRun STBYLabelPin
P203 "SMPS" to CN4 “Inverter"
1ADIM Pin 11 Fixed and not used
2P-DIM Pin 24 can vary according to type of signal being processed and the OSD Backlight setting.
*0.6V 0% to 3.3V 100%. Output from the Video Processor IC100.
P203
LCD DV 42LH9040 February 2010
Power Supply Connector SK100 and SK101 Voltage and Diode CheckPower Supply Connector SK100 and SK101 Voltage and Diode Check
Diode Mode values taken with all Connectors Removed
AC Voltage Readings (From Hot Ground)Pins 1 and 2 for STBY and RUN.
OLNE7
OL120Vac
LE3
Diode CheckRun STBYLabelPin
OLn/aE5
OL120Vac
n/aE4
Diode CheckRun STBYLabelPin
SK100 "SMPS" to AC IN SK101 "SMPS" to MASTER POWER SWITCH
SK101 SK100
Bottom Right of SMPS
Live
Neutral
With the Master Power SwitchClosed (On) AC flows.When Open (Off) AC open and does not flow.
F100
F1008A/250V
AC IN
F100 (Diode Check)Main Power Switch Closed
Red Lead on Fuse (Open)Black Lead on Hot Ground
Black Lead on Fuse (0.525V) Red Lead on Hot Ground
E4 E5
E3
E7
AC Voltage Readings for either pin 1 or pin 2 in STBY and RUN with one lead on Neutral of SK100. (Reading from Hot Ground)Note: With Main Power Switch Open, E5 has no AC. E4 does have AC.
LCD DV 42LH9041 February 2010
INVERTER (LED BACKLIGHTS) SECTIONINVERTER (LED BACKLIGHTS) SECTION
The Inverter receives 24V from the SMPS on CN1 pins 1~5..The Inverter On (INV ON) command from CN1 pin 12 starts the Inverter drive signals.P-DIM is delivered from the Main board through the SMPS to the Inverter on CN1 pin 13.The Inverter is responsible for delivering B+ (27.5V) to each ofthe 64 LED Blocks. This is accomplished by 4 DC to DC Converters (M1~M4) on the board, (easily identified by the 4 yellow capacitors on the lower left of the board.
• M1 and M3 are routed out CN4 • M2 and M4 are routed out CN3.
It also must deliver grounding pulses (Drive Signals) to each of the 64 LED Blocks. This is accomplished by the 32 switching components Q19~Q50 each controlling 2 blocks.
The Left hand connector CN3 connects the 4 LED Boards (32 blocks) on the right side of the screen and the Right hand connector CN4 connects to the 4 LED Boards (32 blocks) on the left.
T-CON
INVERTER
STBY 5V, 12V, 24V
PWR (Power On)Inv On/OffPWM-DIM
24V
P-D
IM
ON/OFF(Inverter On/Off)
VBR-BPWM-DIM
(Global Dimming)
Pulling CN306 will place all LEDs in full bright.
Quad 12 Bit LVDS Video
LVDS 12V
LVDS 12VT-CON develops-5V, 3.3V, 16V, 26V for Panel
PWM-DIM(Global Dimming)
12V24VSTBY 5V
MAIN BOARD
PWR
Relay O
n
LVDS 12V
Quad 12 Bit LVDS Video
To L
ED B
ackl
ight
s
24VINV-ON
Intelligent Sensor(Room Light Monitor) Only affects P-DIM
Customer’s MenuBrightness Selection
Only affects Luminance information
ON/OFF(Inverter On/Off)
IC3502Dimming
Tur-Motion
Luminance Manipulated by the Brightness Setting
Customer’s MenuBacklight Selection Only affects P-DIM
Luminance
I100MstarChip
Backlight setting determines the
Backlight brightness Ceiling
CN1
27.6V
8 LEDsPer/block
DriveSignal
Bright
Medium
Dim
CN4 Controls 4 Boards
Each board controls 2 rows
of 4 Blocks.Total 8 Blocks
DriveSignal
DC Voltage Manipulated by:
Video ContentIntelligent SensorCustomer’s Menu Backlight Setting
Freq: 120Hz
There are two DC to DC converters (27.6V) for each plugCN3/CN4
Called M1-M4
42
42LH90 LED Backlight Controls (Block Diagram)42LH90 LED Backlight Controls (Block Diagram)
P700P201
CN3 Controls 4 BoardsEach board controls 2 rows
of 4 Blocks.Total 8 Blocks
CN1P203
CN306
Drive Signals for CN3 and CN4 going to V1 through V64
(LED Blocks)
P3501
(Pin 1)3.54Vp/p
(Pin 4)3.48Vp/p
(Pin 6)3.46Vp/p
SMPS
CN3
CN4
CN2
CN5 CN4To Panel
CN4/CN5 carry-5V, 3.3V, 16V, 26V and
Video for Panel
12 BitLVDSVideo
IC801XD Engine
12V
Panel C
TL
LocalDimmingControlSignals
12VSwitchQ706
M1-M3
M2-M4
Error
Error
Error
120Hz Backlight Blanking Signal
LCD DV 42LH9043 February 2010
Inverter Connector IdentificationInverter Connector Identification
CN306
CN4
CN1
M1
Chocolate
M2
M3
M4
CN3
27.5VPower
Supplies
CN305 n/c
CN307 n/c
LCD DV 42LH9044 February 2010
General LED Backlight Board Information (As viewed from the FronGeneral LED Backlight Board Information (As viewed from the Front)t)
There are 4 LED Boards per/side, 8 Total.There are 2 Rows of LED blocks per/board.
There are 4 LED blocks per/row.
LCD DV 42LH9045 February 2010
General LED Backlight Block InformationGeneral LED Backlight Block Information
There are 8 LEDs per/block.There are a total of 512 LEDs.
9.4V p/p120 Hz
Connected to CN3 or CN4
LCD DV 42LH9046 February 2010
LED Backlight Basics (LED Layout)LED Backlight Basics (LED Layout)The picture below shows a close up of one of the 512 individual LEDs contained within the backlight boards. There are two sides each with 256 LEDs (32 blocks) in each side.An individual block is manipulated by the Main board Dimming IC IC3502 in accordance with the video intensity at the specific location of the block of LEDs for that video content (Local Dimming). In other words, if the video is dark in the area of the screen that is being illuminated by a block of LEDs, they will be dimmed.
Also, all blocks are manipulated simultaneously via (Global Dimming) by IC100 Video Processor. The Overall intensity of the backlights is manipulated by the “Global Dimming” signal from the Mstar (IC100) chip called Digital-Dimming (PWM-DIM).
Panel Disassembly required.(Not during warranty period.)A simple Forward Bias diode check will cause the diode to illuminate if it is good. Check any pin on the right to any pin on the left.
A minimum of 21V required to light all 8 LEDs in a blockPins 1,2,13,14,16,17,28,29,31,32,43,44,46,47,58,59
On CN3 and CN4
In the Diode Mode Check, the LED will light. (2.6V Reading)
This represents One Block.There are 4 boards per/side.Each board contains 8 Blocks.Totaling 32 Blocks per/side.64 Blocks over all.
LCD DV 42LH9047 February 2010
The graphics below show the relationship between the LEDs reaction to real time video on the screen, this is called “Local Dimming”.
Actual Video capture Actual LED reaction capture
(A) (A)(B) (B)(C) (C)
The areas in the picture on the left shown by A, B, C and D show the dark areas of the screen.The picture on the right shows the backlight LEDs. Note they are dimmed out in the same area as the dark video on the left.
To see a representation of the “Local Dimming” the TV has to be set to the “Store Mode”.
Note: These graphics are from the 47LG90 which has more LEDs than the 42LH90, but the explanation remains the same.
LED Backlight Basics (Local Dimming)LED Backlight Basics (Local Dimming)
LCD DV 42LH9049 February 2010
Inverter 27V (M 1Inverter 27V (M 1--M4 Power Supplies) InformationM4 Power Supplies) Information
There are actually 4 power supplies developing the operational B+ (27.5V) for the LED blocks. They are designated as “M1 through M4”.Each of the 4 have the same components.
M1
M2
M3
M4
27.5VTP
Each of the 4 capacitors C12, C27, C212 and C227 have a TP just above the (+) leg of the cap.
LCD DV 42LH9050 February 2010
Inverter Component Top Half IdentificationInverter Component Top Half Identification
Q35 - Q50Are LED Block Drivers for CN3
Q19 - Q34Are LED Block Drivers fro CN4
D302 blinks at 1Hz when all
is OK
Q19 through Q50Note: Each output driver (switch) has a TP
to the left and right representing a “V”which indicates a Block of LEDs.
In the example Q35 above; V34 represents Pin 23 of CN4V33 represents Pin 24 of CN4
Grounding these points when the 27.6V supplies are working will cause the entire
Block of Backlight LEDs to turn on.(100mA to light one block)
Example
CN327.5V Line on CN3
Pins 1-2 (Out_M2)Pins 13-14 (Out_M2)Pins 16-17 (Out_M2)Pins 26-29 (Out_M2)Pins 31-32 (Out_M4)Pins 43-44 (Out_M4)Pins 46-47 (Out_M4)Pins 58-59 (Out_M4)
CN427.5V Line on CN4
Pins 1-2 (Out_M3)Pins 13-14 (Out_M3)Pins 16-17 (Out_M3)Pins 26-29 (Out_M3)Pins 31-32 (Out_M1)Pins 43-44 (Out_M1)Pins 46-47 (Out_M1)Pins 58-59 (Out_M1)
Local Dimming Control SignalsTo P306 from Main
Example: Q35
Voltage Supplies to each connector.
LCD DV 42LH9051 February 2010
Inverter LED D302 InformationInverter LED D302 InformationLED D302
LED D302 blinks at 1Hz to indicate that the Inverter is running correctly.
When it blinks at any other rate, it indicates there is an abnormal state of the Inverter.
When it doesn’t blink, check the 24V arriving at the board on CN1 pins 1~5.Check the two fuses F1 and F2 for 24V.Check IC302 and IC303 regulator voltages (see page 56).
LCD DV 42LH9052 February 2010
Inverter Fuse F1 and F2 CheckInverter Fuse F1 and F2 Check
F12A/125VCenter of the Board
Left of CN1 Connector
F1 or F2 (Diode Mode Check)Open (Red Lead on Fuse)
0.46V (Black Lead on Fuse)
F212A/65V
F1 or F2Normal 24V in Run
LCD DV 42LH9053 February 2010
Inverter Crystal Y301 InformationInverter Crystal Y301 Information
Crystal Y301
LCD DV 42LH9054 February 2010
Inverter 27V (M 1Inverter 27V (M 1--M4 Power Supplies) ChecksM4 Power Supplies) Checks
Example of M3 (27.5V) Power SupplyThere are actually 4 power supplies developing 27.5V for the LED blocks. They are designated as “M1 through M4” This one is M3. Each of the 4 have the same components.
Q4, Q5, Q11, Q11, Q12, Q204, Q205, Q211, Q212
Gnd 3.67V
23.9V
D2, D3, D7, D8, D202, D203, D207, D208
Gnd26.4V28.0V Gnd
3.74V 3.73VGnd 4.0V 6.75V 4.0V
Q2, Q10,Q202, Q210
Q3, Q09Q203, Q209
LCD DV 42LH9055 February 2010
Inverter IC2, IC4 and IC15 ChecksInverter IC2, IC4 and IC15 Checks
Center of the Board
GND
IC2
4.6V GND
GND
1.0V 7V
24V
IC4
IC15
3.29V
6.99V
0.46V
1.71V
6.95V
LCD DV 42LH9056 February 2010
Inverter IC303 and IC302 Checks (Controller IC301 B+)Inverter IC303 and IC302 Checks (Controller IC301 B+)
Top of the Board
GND
IC303
GND
IC302
7.0V
3.3V
7.0V
1.8V
LCD DV 42LH9057 February 2010
Inverter Board Connector CN3, CN4 to the Panel (Voltage and DiodInverter Board Connector CN3, CN4 to the Panel (Voltage and Diode Check)e Check)
OPEN0Vn/c60OPEN27.0VOut_M458~59OPEN0Vn/c57OPEN0.7-1.2VV61~V6453~56OPEN0.7-1.2VV56~V5349~52OPEN0Vn/c48OPEN27VOut_M446~47OPEN0Vn/c45OPEN27VOut_M443~44OPEN0Vn/c42OPEN0.7-1.2VV45~V4838~41OPEN0.7-1.2VV40~V3734~37OPEN0Vn/c33OPEN27.0VOut_M431~32OPEN0Vn/c30OPEN27.0VOut_M228~29OPEN0Vn/c27: n/cOPEN0.7-1.2VV29~V3223~26OPEN0.7-1.2VV24~V2119~22OPEN0Vn/c18OPEN27.0VOut_M216~17OPEN0Vn/c15OPEN27.0VOut_M213~14OPEN0Vn/c12OPEN0.7-1.2VV13~V168~11OPEN0.7-1.2VV8~V54~7OPEN0Vn/c3OPEN27.0VOut_M21~2
ResistanceRunLabelPin
OPEN27VOut_M31~2OPEN0Vn/c3OPEN0.7-1.2VV57~604~7OPEN0.7-1.2VV52~V498~11OPEN0Vn/c12OPEN27.0VOut_M313~14OPEN0Vn/c15OPEN27.0VOut_M316~17OPEN0Vn/c18OPEN0.7-1.2VV41~V4419~22OPEN0.7-1.2VV34~V3323~26OPEN0Vn/c27OPEN27.0VOut_M328~29OPEN0Vn/c30OPEN27.0VOut_M131~32OPEN0Vn/c33OPEN0.7-1.2VV25~V2834~37OPEN0.7-1.2VV20~V1738~41OPEN0Vn/c42OPEN27.0VOut_M143~44OPEN0Vn/c45: n/cOPEN27.0VOut_M146~47OPEN0Vn/c48OPEN0.7-1.2VV9~V1249~52OPEN0.7-1.2VV4~V153~56OPEN0Vn/c57OPEN27VOut_M158~59OPEN0Vn/c60
ResistanceRunLabelPin
CN3 Inverter to Panel CN4 Inverter to Panel
Note 46-47Incorrect
Silk Screening on Board.
Inverter Run voltages taken
with built in test pattern full
white screen
Diode Mode values taken with all Connectors Removed
LCD DV 42LH9058 February 2010
Inverter Board Connector CN1 to the P203 Inverter Board Connector CN1 to the P203 ““SMPSSMPS”” (Voltage and Diode Check)(Voltage and Diode Check)
2.9V24.0V0VVIN1
2.9V24.0V0VVIN2
2.9V24.0V0VVIN3
2.9V24.0V0VVIN4
2.9V24.0V0VVIN5
GNDGNDGNDGND6
GNDGNDGNDGND7
GNDGNDGNDGND8
GNDGNDGNDGND9
GNDGNDGNDGND10
OPEN1.66V0.47VNC11
1.6V4.65V0VON/OFF12
OPEN0.33V-3.2V0VExt_VBR_B13
OPEN0V0VAGP14
Diode ModeRun STBYLabelPin
CN1 Connector “Inverter” to P203 “SMPS”
Inverter Run voltages taken with built in test pattern full white screen
Diode Mode values taken with all Connectors Removed
P-DIM
Ext_VBR_B(P-DIM) Pin 13
can vary according to type
of signal being processed and
the OSDBacklight setting.
0.33V 0% to 3.3V 100%.
Output from the Video Processor
IC100.
Error
LCD DV 42LH9059 February 2010
Inverter Board Connector CN306 to the P3501 Inverter Board Connector CN306 to the P3501 ““MainMain”” (Voltage and Diode Check)(Voltage and Diode Check)
CN306 Connector “Inverter” to P3501 “Main”
OPEN0.02V0VScel1
OPEN0V0VNC2
OPEN0V0VNC3
OPEN0.7 TO 3.0V*0V*Din4
OPEN0V0VGND5
OPEN0V0VDclk6
OPEN0V0VGND7
GND0V0VGND8
ResistanceRun STBYLabelPin
* Local Dimming Off 0.85V
Inverter Run voltages taken with built in test pattern full white screen
Diode Mode values taken with all Connectors Removed
LCD DV 42LH9060 February 2010
LCD Panel Controller BoardThe T-Con Processor UC1 receives from the Main Board via CN1 dual 12 Bit LVDS (Video) Signals and CN2 dual 12 Bit LVDS (Video) Signals. Both LVDS cables are carrying 24 bit signals.
UC1 then processes these signals into TFT Drive Signals. It delivers its output signals through connectors CN4 and CN5 to drive the LCD Panel.
12V is supplied to the T-Con Board on connector CN1 from the Main Board(easily measured at fuse F1).
There is one regulator that creates 1.8V developed at pin 2 (Center Leg) of U11.
U5 is a DC to DC converter IC which develops the Panels driver voltages. 16V, 3.3V, -5V and 26V.
These voltages can be read at the ribbon connector or at test points on the board which will be identified later.
TT--CON (TFT DRIVE) BOARD SECTIONCON (TFT DRIVE) BOARD SECTION
LCD DV 42LH9061 February 2010
TT--CON (TFT Drive) Board (Shield Removed)CON (TFT Drive) Board (Shield Removed)
F1
CN5 CN4
UC1
ToMain Board
To TFT Panel To TFT Panel
Remember to replace screws for ground purposes if testing the Board.
T-CON p/n: EAT60665101
CN1 CN2
U12
U11 U5
D9
D10
D8
D7
U10
Q1
FL2
FL1
42LH90 T-CON (TFT Drive) Board Drawing (Components and Voltages Identified)42LH90 T-CON (TFT Drive) Board Drawing (Components and Voltages Identified)
62
P/N EAT60665101
TO TFT MODULE
125V / 3A
CN5 CN4
TO TFT MODULE
UC1
FL1
D8
L1
F1 (12V)
TO TFT MODULE
T-CON(TFT Driver)
Gnd Protect
FL2Gnd Protect
CN1
U11
D7
L2D9
D10
Q1
U12
U10
Pin 2Pin 4
Pin 56,57,58Pin 53,54
U5
1) 0V2) 1.19V3) 3.3V B
2.78VE
3.3V
C3.3V
16V
20.5V 14.25V
-2.4V
12
32
R701R702
R70
4R
705
R70
6
16V26V
27V
26V16V -4.9V3.3VPin 59
Pin 57Pin 3,4,5
Pin 7,826V16V-4.9V3.3V
C74
4R
721
( 12V )
U5
Gnd -4.9V
U5 B+ ( 12V )
3.3VVCC
16V
3.3V
CN2
VDD1) Gnd2) Gnd3) Gnd4) Gnd
8) 3.34V7) 3.09V6) 3.34V5) 3.34V
12V LVDS Pins 48~51
LCD DV 42LH9063 February 2010
TT--CON (TFT Drive) Board ChecksCON (TFT Drive) Board Checks
Check Fuse F1 for 12V from CN1 Pins 48~51
Check the Regulator U11 for Correct Voltage
T-CON Board
0V
3.3V
1.8V
CN1
F1
U11
U11 has a piece of “Chocolate” which is heat
transfer material. Transfer if board is replaced.
F1 (Diode Mode Check)Open (Red Lead on Fuse)
0.46V (Black Lead on Fuse)
LCD DV 42LH9064 February 2010
T-CON Board
-5VSource
D9 Anode
26VSourcePin 8
16V (VDD)Pin 42
3.3V TPVCC
3.3V Source Pin 23, 24
16V (D6)Not for Panel Cathode
16.9V
D7Cathode 3.3V
12VPin 37,38Chip B+
TT--CON (TFT Driver) Board CN4 and CN5 (Voltage Sources)CON (TFT Driver) Board CN4 and CN5 (Voltage Sources)
12VPin 25,26Chip B+
D7
U5
LCD DV 42LH9065 February 2010
CN5 CN4
T-CON Board
CN5 CN4
-5VPin 59
26VPin 57
16VPin 3,4,5
3.3VPin 7,8
16VPin 56,57,58
3.3VPin 53,54
-5VPin 2
26VPin 4
TT--CON (TFT Driver) Board CN4 and CN5 (Voltage Check)CON (TFT Driver) Board CN4 and CN5 (Voltage Check)
LCD DV 42LH9066 February 2010
TT--CON Board Connector CN1 to the Main Board (Voltage and Diode ChCON Board Connector CN1 to the Main Board (Voltage and Diode Check)eck)Diode Mode values taken with all Connectors RemovedCN1 “T-CON“ to P3500 CONNECTOR "Main"
Diode TestRunLabelPin
Open1.26VURSA-ACKM20
Open1.25VURSA-ACKP19
GndGndGnd18
Open1.4VURSA-A2M17
Open1.4VURSA-A2P16
Open1.2VURSA-A1M15
Open1.3VURSA-A1P14
Open1.2VURSA-A0M13
Open1.3VURSA-A0P12
Openn/cOPC-Out211
Openn/cOPC-EN10
Openn/cOPC-Out9
Openn/cPWM-DIM*8
Gndn/cLVDS-Sel7
n/cn/cn/c6
n/cn/cn/c5
n/cn/cn/c4
n/cn/cn/c3
n/cn/cn/c2
GndGndGnd1
Diode TestRunLabelPin
Open1.44VURSA-B4P40
Open1.21VURSA-B3M39
Open1.2VURSA-B3P38
GndGndGnd37
Open1.22VURSA-BCKM36
Open1.21VURSA-BCKP35
GndGndGnd34
Open1.22VURSA-B2M33
Open1.21VURSA-B2P32
Open1.1VURSA-B1M31
Open1.4VURSA-B1P30
Open1.1VURSA-B0M29
Open1. 4VURSA-B0P28
n/cn/cn/c27
GndGndGnd26
Open1.1VURSA-A4M25
Open1.4VURSA-A4P24
Open1.1VURSA-A3M23
Open1.4VURSA-A3P22
GndGndGnd21
Diode TestRunLabelPin
Open12VLVDS 12V51
Open12VLVDS 12V50
Open12VLVDS 12V49
Open12VLVDS 12V48
n/cn/cn/c47
GndGndGnd46
GndGndGnd45
GndGndGnd44
GndGndGnd43
GndGndGnd42
Open1.09VURSA-B4M41
LCD DV 42LH9067 February 2010
TT--CON Board Connector CN2 to the Main Board (Voltage and Diode ChCON Board Connector CN2 to the Main Board (Voltage and Diode Check)eck)Diode Mode values taken with all Connectors RemovedCN2 “T-CON“ to P3502 CONNECTOR "Main"
Diode TestRunLabelPin
Open1.3VURSA-C3P20
GndGndGnd19
Open1.23VURSA-C2M18
Open1.23VURSA-C2P17
GndGndGnd16
Open1.2VURSA-C2M15
Open1.3VURSA-C2P14
Open1.2VURSA-C1M13
Open1.3VURSA-C1P12
Open1.2VURSA-C0M11
Open1.28VURSA-C0P10
GndGndGnd9
n/cn/cn/c8
n/cn/cn/c7
n/cn/cn/c6
n/cn/cn/c5
n/cn/cn/c4
n/cn/cn/c3
n/cn/cn/c2
n/cn/cn/c1
Diode TestRunLabelPin
GndGndGnd41
GndGndGnd40
Open1.15VURSA-D4M39
Open1.4VURSA-D4P38
Open1.25VURSA-D3M37
Open1.3VURSA-D3P36
GndGndGnd35
Open1.29VURSA-DCKM34
Open1.23VURSA-DCKP33
GndGndGnd32
Open1.2VURSA-D2M31
Open1.3VURSA-D2P30
Open1.3VURSA-D1M29
Open1.29VURSA-D1P28
Open1.25VURSA-D0M27
Open1.29VURSA-D0P26
GndGndGnd25
GndGndGnd24
Open1.18VURSA-C4M23
Open1.13VURSA-C4P22
Open1.2VURSA-C3M21
LCD DV 42LH9068 February 2010
MAIN BOARD SECTIONMAIN BOARD SECTION
The Main board receives its operational B+ from the Power Supply via P400. There are two LVDS cable feeds that go to the T-CON (TFT Driver) section. These carry the duel 12 bit LVDS Video signals and the TruMotion 60Hz duel 12 bit LVDS. These signals have already been prepared for the T-CON board. The Main board also includes the Tuner, Audio and Audio/Video inputs and selection circuits.
STAND-BY• STBY 5V pins 7~10
The Main board also develops several B+ sources on the board.
LVDS• LVDS 12V (Not generated, but switched
from the 12V arriving from the SMPS. AUDIO• 3.3V• 1.8V
Mstar IC100 Video and Micro Processors• 1.2V
IC3502 Tru-Motion and Dimming IC.• 1.26V_MEMC, 1.8V_MEMC,
1.8V_DDR, and 3.3V
RUN • 12V pins 13 and 14 • 24V pins 17 and 18.
TUNER and VSB CIRCUIT • 9V which is used to make 5V TU • 5V TU• 3.3V• 1.2V
STAND-BY VOLTAGES• 3.3V_ST
GENERAL• 5V_General• 5V_EXT
Input Voltages from SMPS.
LCD DV 42LH9069 February 2010
Main Board LayoutMain Board Layout
VIDEO PROCESSOR
IC100 and Tru-Motion IC3502
runs Hot. This is normal.
P3501to Inverter
SW3500Not
used
X100
P3500
SW100Reset
IC100Micro/VideoProcessor
X800
IC3502Dimming
Tru-Motion
P600to Speakers
P1200to IR Board
TunerTU1001
n/c
HDMISelector
DDR
DDR
P700to SMPS
IC600Audio
IC801
X3500
USB
Rear Inputs
To Panel
P3502
70
P3500
IC3502Tru-
Motion/Dimming
P3502
IC3502 Operates at high temperature
P3501
P700
X350025Mhz
IC3503
IC3504
IC3500
Q706
E
C
B
Q702
IC706
E
C
BQ701
L718
L710
IC701
L726
IC705
IC704
IC2
SW3500Not Used
XDEngine
IC801
IC901
IC900
X80012Mhz
IC1
X10012Mhz
IC100Micro/VideoProcessor
Mstar
IC707
L712IC708
IC1000IC1001
IC101
SW100
EC B
Q100
IC105
IC502IC600
L607
L606
P1200E
C B
Q106
IC1002
Q1200
ECB
IC1203
TU1001 TunerTDVW-H103F
(1)
Analog Video (19)
Tuner 5V_TU (4)
Data (8)Clock (9)
Dig DIF+ (12)Dig DIF- (13)
SIF (16)
X100525Mhz
P101N/A
IC1004
D1000
12V LVDSPins 1~4
P600
42LH90MAIN
BOARD
42LH90Main Board (Front Side)
Component Layout
42LH90Main Board (Front Side)
Component Layout
42LH90 Main (Front Side) Component VoltagesIC101 Serial Flash IC705 +1.26V_VDDC IC1000 +1.26V_PVSB IC3503 +1.8V Reg Q706 +5V/12VLVDS
Pin Memory Pin Regulator Pin Regulator Pin Dimming Pin Switch[1] 0.05V [1] 0.8V [1] 0V [1] 0.58 [1] 5.1V[2] 3.2V [2] Gnd [2] 3.39V [2] 1.8V [2] 0.29V[3] 2.5V [3] 5V [3] 3.4V [3] 3.19V [3] 11.9V[4] Gnd [4] 6V [4] 0V [4] 5.99V[5] 0V [5] 3.2V [5] 0V IC3204 Dimming [5] 11.98V[6] 0V [6] 1.2V [6] 1.21V Pin EEPROM [6] 11.98V[7] 3.3V [7] 1.26V [7] 0.8V [1] Gnd [7] 5.06V
[8] 3.3V [8] 5V [8] Gnd [2] Gnd [8] 5.06V[3] Gnd
IC105 HDCP IC706 5V_EXT IC1001 +3.3V_PVSB [4] Gnd Q1200 IR RS232Pin EEPROM Pin Memory Pin +3.3V_FE [5] 3.3V Pin Buffer[1] Gnd [1] 0.8V [1] 4.94V [6] 3.3V B 0.634V[2] Gnd [2] Gnd [2] 4.94V [7] 0V C 0.97V[3] 3.29V [3] 12V [3] Gnd [8] 3.3V E Gnd[4] Gnd [4] 9.6V [4] 3.4V[5] 3.3V [5] 5V [5] 1.25V Q100 W/P IC101 D1000 Speed Up Reset[6] 3.3V [6] 4.97V Pin Pin IC1004[7] 0V [7] 4.97V IC1002 +5V_TU B 0V C 3.4V
[8] 3.3V [8] 1.9V Pin Tuner C 2.5V A 3.38V[1] 8.92V E Gnd
IC701 +1.8V_DDR IC707 +1.8V_MEMC [2] 1.88VPin Regulator Pin Regulator [3] 5.04V Q106 S5/S6 Reset[1] 0V [1] 0.8V [4] 0V Pin Mstar[2] 3.2V [2] Gnd [5] Gnd B 0V[3] 3.2V [3] 4.92V C 3.28V[4] n/c [4] 6.5V IC1203 SPIF Optical E 0V[5] n/c [5] 4.8V Pin Audio[6] 1.8V [6] 1.8V [1] 1.58V Q702 INV_ON[7] 0.8V [7] 1.8V [2] 3.2V Pin Inverter
[8] Gnd [8] 4.8V [3] Gnd B 0.05V[4] 1.61V C 4.66V
IC704 +3.3V_FE IC708 +1.26V_MEMC [5] 3.21V E GndPin Regulator Pin Regulator[1] 0.8V [1] Gnd IC3500 +3.3V_Dimming[2] Gnd [2] 0.8V Pin Regulator[3] 5V [3] 1.26V [1] Gnd[4] 7.5V [4] 1.26V [2] 3.3V[5] 5V [5] 1.8V [3] 5V[6] 3.3V [6] 5V[7] 3.3V [7] 1.26V
[8] 2.1V [8] 5V
71
42LH90Main Board (Back Side)
Component Layout
42LH90Main Board (Back Side)
Component Layout
72
1
TUN
ER TU
1001
(5V) 4TD
VW-H
103F
13 DIF -12 DIF +
16 SIF
19 Video
IC3505
C
A1
A2
D1223
IC1200
IC1201
D500
C
A1A2
EC B
Q1001 EC B
Q1000
IC1003IC703
ECB
C
A1
A2
EC B
23 1
Q105
IC103
IC702IC104
FLAS
H
IC102
IC800
IC1202
IC501
Q703 E CBQ704 E CBQ705 E CB
IC1072
3
1
Q600
D102
42LH90 MAIN BOARD(Back View)
42LH90 Main (Back Side) Component VoltagesIC103 Reset Gen IC1003 9V Reg IC3505 Reset Gen Q1001 Tuner Video
Pin Mstar IC100 Pin to IC1002 Pin for IC3502 Pin Buffer[1] Gnd [1] 12V [1] 3.3V B 3.09V[2] 0V [2] Gnd [2] Gnd C 0V[3] 3.3V [3] 8.9V [3] 3.22V E 3.72V
For Tuner Voltage 5VIC104 RGB (PC) Q105 PWR On Delay D102 Audio Mute
Pin EEPROM IC1200 RGB Pin Q2405 Pin Routing[1] Gnd Pin EEPROM B 0V A1 0.047V[2] Gnd [1] Gnd C 1.95V C 0.089V[3] Gnd [2] Gnd E Gnd A2 0V[4] Gnd [3] Gnd[5] 3.22V [4] Gnd Q600 Audio Mute D500 Shunt for[6] 3.22V [5] 4.82V Pin Switch Pin IC501[7] 0V [6] 4.82V B 0.08V A1 3.25V[8] 3.22V [7] 4.82V C 3.26V C 3.12V
[8] 4.82V E Gnd A2 0VIC107 Power Det
Pin Gen IC1201 RS232 Q703 5V Switch D1223 5V Routing[1] Gnd Pin Rx/Tx Pin Control Pin for IC1200[2] 3.9V [1] 3.3V B 0.6V A1 0V[3] 3.28V [2] 5.56V C 0.03V C 4.82V
[3] 0.02V E Gnd A2 5.11VIC702 +3.3V_ST [4] 0.03V
+3.3V_AVDD_MPLL [5] 5.46V Q704 12V LVDSPin Regulator [6] 5.5V Pin Switch Control[1] Gnd [7] 5.5V B 0.05V[2] 3.29V [8] 0V C 0.65V[3] 5.11V [9] 3.29V E Gnd
[10] 3.24VIC703 +3.3V_ST [11] 0.02V Q705 12V LVDS
Pin Regulator [12] 3.29V Pin Switch[1] 0V [13] 0V B 0.65V[2] 1.8V [14] 5.5V C 0.0V[3] 3.21V [15] Gnd E Gnd
[16] 3.29VQ1000 Tuner SIF
IC800 SPI Flash IC1202 USB +5V Pin BufferPin Pin Switch B 2.4V[1] 0.12V [1] 4.95V C 0V[2] 1.13V [2] Gnd E 3.85V[3] 3.26V [3] 3.21V[4] Gnd [4] 4.95V[5] 0.06V [5] 0V[6] 1.2V [6] 4.95V[7] 3.27V [8] 3.27V
31 2
3
73
LCD DV 42LH9074 February 2010
Main Board X100 and X800 Crystal ChecksMain Board X100 and X800 Crystal Checks
2.56Vp/p 12MhzSet on or off. Use bottom leg.
IC100 Microprocessor Crystal
MAIN Board
X100
X800
Set on. Use bottom leg.2.25Vp/p 12Mhz
IC800 XD Engine Crystal
1.58V
1.51V
1.54V
1.59V
LCD DV 42LH9075 February 2010
Main Board X3500 and X1005 Crystal CheckMain Board X3500 and X1005 Crystal Check
3.94Vp/p 25Mhz Set on. Use Left leg.
IC3502 Dimming IC Crystal
MAIN Board
X1005
Set on. Use Top leg.3.54Vp/p 25Mhz
IC1005 Tuner Control IC Crystal
X3500
1.64V
1.54V
Dimming/Tru-Motion
1.54V 1.57V
5.67Vp/p25MhzBottom
Leg
5.34Vp/p 25MhzRight Leg
LCD DV 42LH9076 February 2010
Main Board LD1000 FunctionMain Board LD1000 Function
Main BoardLD1000 Location
Use LD1000 as a visual aid.This lets you know the PLL (Phase Lock Loop)
circuit is working correctly in IC1004.This indicates the Tuner Crystal is Locked to the
Reference frequency in IC1004.
LD1000
LCD DV 42LH9077 February 2010
Main Board Connector P700 to Power Supply Voltage and Diode ChecMain Board Connector P700 to Power Supply Voltage and Diode Checkk
Diode Mode values taken with all Connectors Removed
2.6V5V0VPWR-ON2GndGndGndGnd4GndGndGndGnd61.1V5.15V5.15V5.2V81.1V5.15V5.15V5.2V10GndGndGndGnd122.2V12V0V12V14GndGndGndGnd16Open24V0V24V182.9V4.65V0VInv_On20Open0V0VErr Out221.3V2.43V0V2PDIM24
Diode CheckRun STBYLabelPin
Openncncnc1GndGndGndGnd3GndGndGndGnd51.1V5.15V5.15V5.2V71.1V5.15V5.15V5.2V9GndGndGndGnd112.2V12V0V12V13GndGndGndGnd15
Open24V0V24V17Openncncnc19Open1.66V0.47V1A.DIM21Openncncnc23
Diode CheckRun STBYLabelPin
1ADIM Pin 21 Fixed and not used.It is an Open connection on the Inverter Board.
2PDIM Pin 24 can vary according to type of signal being processed, OSD Backlight setting. 0.6V 0% to 3.3V 100% and the Intelligent Sensor. Output from the Video Processor IC100.
P700 “Main Board" to P201 “SMPS"Odd Pins Even Pins
P700
LCD DV 42LH9078 February 2010
Main Board Connector P3500 to the TMain Board Connector P3500 to the T--CON Voltage and Diode CheckCON Voltage and Diode CheckDiode Mode values taken with all Connectors RemovedP3500 CONNECTOR “Main" to “T-CON“ CN1
0.87V1.4VLVDS_CH2_C-20
1.23V1.13VLVDS_CH2_C+19
GndGndGnd18
1.25V1.21VLVDS_CH2_CLK-17
1.14V1.22VLVDS_CH2_CLK+16
GndGndGnd15
1.23V1.44VLVDS_CH2_D-14
1.23V1.09VLVDS_CH2_D+13
0.875V1.44VLVDS_CH2_E-12
1.23V1.09VLVDS_CH2_E+11
GndGndGnd10
GndGndGnd9
GndGndGnd8
GndGndGnd7
GndGndGnd6
n/cn/cn/c5
Open12VLVDS 12V4
Open12VLVDS 12V3
Open12VLVDS 12V2
Open12VLVDS 12V1
Diode TestRunLabelPin
1.05V1.3VLVDS_CH1_A-40
1.18V 1.2VLVDS_CH1_A+39
1.23V1.3VLVDS_CH1_B-38
1.11V 1.2VLVDS_CH1_B+37
1.22V1.4VLVDS_CH1_C-36
0.88V1.4VLVDS_CH1_C+35
GndGndGnd34
1.2V1.25VLVDS_CH1_CLK-33
1.20V1.26VLVDS_CH1_CLK+32
GndGndGnd31
1.23V1.4VLVDS_CH1_D-30
1.23V1.1VLVDS_CH1_D+29
1.23V1.4VLVDS_CH1_E-28
0.87V1.1VLVDS_CH1_E+27
GndGndGnd26
n/cn/cn/c25
0.88V1.4VLVDS_CH2_A-24
1.22V1.1VLVDS_CH2_A+23
1.2V1.4VLVDS_CH2_B-22
0.87V1.1VLVDS_CH2_B+21
Diode TestRunLabelPin
GndGndGnd51
Openn/cn/c50
Openn/cn/c49
Openn/cn/c48
Openn/cn/c47
Openn/cn/c46
Openn/cLVDS-Sel45
Openn/c*PWM-DIM44
Openn/cOPC-Out43
1.09Vn/cOPC-EN42
GndGndGnd41
Diode TestRunLabelPin
PWM-DIM (Pin 44) is Open on the Main Board.
1
P3500
LCD DV 42LH9079 February 2010
Main Board Connector P3502 to the TMain Board Connector P3502 to the T--CON Voltage and Diode CheckCON Voltage and Diode CheckDiode Mode values taken with all Connectors RemovedP3502 CONNECTOR “Main" to “T-CON“ CN2
1.07V1.13VLVDS_CH3_E-20
1.08V1.18VLVDS_CH3_E+19
GndGndGnd18
GndGndGnd17
0.87V1.29VLVDS_CH4_A-16
1.23V1.25VLVDS_CH4_A+15
0.87V1.29VLVDS_CH4_B-14
1.23V1.3VLVDS_CH4_B+13
0.87V1.3VLVDS_CH4_C-12
0.87V1.2VLVDS_CH4_C+11
GndGndGnd10
1.23V1.3VLVDS_CH4_CLK-9
1.22V1.29VLVDS_CH4_CLK+8
GndGndGnd7
1.12V1.3VLVDS_CH4_D-6
0.87V1.25VLVDS_CH4_D+5
1.24V1.4VLVDS_CH4_E-4
1.18V1.15VLVDS_CH4_E+3
GndGndGnd2
GndGndGnd1
Diode TestRunLabelPin
GndGndGnd41
n/cn/cn/c40
n/cn/cn/c39
n/cn/cn/c38
n/cn/cn/c37
n/cn/cn/c36
n/cn/cn/c35
n/cn/cn/c34
GndGndGnd33
0.87V1.28VLVDS_CH3_A-32
1.20V1.2VLVDS_CH3_A+31
1.23V1.3VLVDS_CH3_B-30
0.87V1.2VLVDS_CH3_B+29
0.87V1.3VLVDS_CH3_C-28
1.03V1.2VLVDS_CH3_C+27
GndGndGnd26
0.87V1.23VLVDS_CH3_CLK-25
0.87V1.3VLVDS_CH3_CLK+24
GndGndGnd23
1.23V1.3VLVDS_CH3_D-22
1.2V1.2VLVDS_CH3_D+21
Diode TestRunLabelPin 1P3502
LCD DV 42LH9080 February 2010
Main Board Connector P1200 to (Ft. IR/Intelligent Sensor) VoltagMain Board Connector P1200 to (Ft. IR/Intelligent Sensor) Voltage and Diode Checke and Diode Check
Diode Mode values taken with all Connectors Removed
P1200 CONNECTOR "MAIN Board" to P101 "Front IR / Intelligent Sensor Board"
Open3.2V0VPWR On120.67V3.2V3.2V3.3V_ST11OpenGndGndGnd10Open3.5V3.5VIR9GndGndGndWARM_ST8GndGndGndGnd71.1V5.1V5.1V5V_ST61.0V3.2V3.2VKey251.0V3.2V3.2VKey14GndGndGndGnd31.6V3.2V0.57VSDA21.6V3.2V0.57VSCL1
Diode CheckRun STBYLabelPinP1200
1
LCD DV 42LH9081 February 2010
Main Board Connector P600 to Speakers Voltage and Diode CheckMain Board Connector P600 to Speakers Voltage and Diode Check
Diode Mode values taken with all Connectors Removed
P400 CONNECTOR "Main" to "Speakers"
SPK-L(+)SPK-L(-)SPK-R(+)SPK-R(-)LABEL
2.63V12V0V42.63V12V0V32.63V12V0V22.63V12V0V1
Diode CheckRunSBYPin
Use speaker out to test for defective Audio Amp IC600Note: (Normal, ½ Audio B+)
P600
Q600Back of board
Audio B+24V
Pins 49-52
MutePin 25
Q400 (Mute) Active Low. Normal 3.3V Collector to Pin 25
IC600 Mute Driver
LCD DV 42LH9082 February 2010
FRONT (IR, INTELLIGENT SENSOR and MOVING LED) SECTIONFRONT (IR, INTELLIGENT SENSOR and MOVING LED) SECTION
The Intelligent Sensor and IR board (located on the bottom left as viewed from the rear) contains the IR (Infrared Remote Sensor) and the Intelligent Sensor. This board also connects with the Side Key Board and the Moving LED board which contains the 10 front Power LEDs.
The IR board receives it operating B+ via P101 pin 6 (STBY 5V) and pin 11 (3.3V) from connector P1200 on the Main board.
The Intelligent Sensor communicates with the Micro/Video Processor IC100 Mstar Chip via clock and data lines SCL1 and SDA1 (AA17 and AA18) arriving on connector P101 from P700 pins 1 and 2 on the Main board.
The Front Power LEDs are controlled by these same Clock and Data lines which communicate with the LED Driver IC U1 on the Moving LED board.
The IR pulses (5V p/p) P101 pin 9 are sent to P1200 on the Main board and on to the Microprocessor (IC100) via pin C4.
The Key board is routed to the IR board via P100 to P102 on the Key 1 and Key 2 lines, (Key 1 pin 1 and Key 2 pin 3). Then out P101 pins 4 and 5 to P1200 on the Main Board. Then to the Microprocessor A4 and B4 lines.
LCD DV 42LH9083 February 2010
Front Boards (Connections Identified)Front Boards (Connections Identified)
P100
P100
P101
Intelligent Sensor / IR board
p/n EBR62128101
P102
Moving LED board(Power LEDs)
p/n EBR61674001
p/n EBR62127501
Key board
J1
LCD DV 42LH9084 February 2010
Front Moving LED Board IdentifiedFront Moving LED Board Identified
The Front LED Board (located on the bottom left as viewed from the rear)
Contains the front Power LEDs.
Power LEDs
J1 ConnectorTo Intelligent
Sensor and IR Board
U1LED Driver
Pin 1
LCD DV 42LH9085 February 2010
Front Board Connectors P101 and P2 Voltage and Diode CheckFront Board Connectors P101 and P2 Voltage and Diode Check
Diode Mode values taken with all Connectors Removed
P101 CONNECTOR "Front IR / Intelligent Sensor" to P1200 " MAIN Board "
Open3.2V0VLED On12Open3.2V3.2V3.3V11GndGndGndGnd10Open3.5V3.5VIR9OpenGndGndWarm_ST8GndGndGndGnd7
Open5.1V5.1VST_5V6Open3.2V3.2VKey25Open3.2V3.2VKey14GndGndGndGnd3Open3.2V0.57VSDA2Open3.2V0.57VSCL1
DiodeCheckRun STBYLabelPin
P2 Connector to “Side Key" P100
Gnd
Open
Gnd
Open
DiodeCheck
GndKey 2Gnd
Key 1
Label
GndGnd43.2V3.2V3GndGnd232V3.2V1
Run STBYPin
LCD DV 42LH9086 February 2010
Front Board Connector P100 and J1 Voltage and Diode CheckFront Board Connector P100 and J1 Voltage and Diode Check
Diode Mode values taken with all Connectors Removed
P100 CONNECTOR "Front IR / Intelligent Sensor" to J1 "Moving LED Board"
Open0V0V8Open*3.27V*0V7GndGndGnd6
Open5V0.75V5GndGndGnd4
Open4.9V0.59V3GndGndGnd2
Open5V5V1
DiodeCheckRun STBYPin
*Pin 7: From Pin 12 of P101 IR boardFrom Pin 12 of P1200 Main boardFrom R196 Main boardFrom Pin GPIO96 of Micro IC100
J1 "Moving LED Board"P100 CONNECTOR "Front IR / Intelligent Sensor"
Open8Open7Gnd6Open5Gnd4Open3Gnd2Open1
DiodeCheckPin
Pin 7: From Pin 7 of P100
See P100Table for Voltages
LCD DV 42LH9087 February 2010
SIDE KEY BOARD SECTION p/n EBR62127501SIDE KEY BOARD SECTION p/n EBR62127501
SW106
SW104
SW102
SW100
SW107
SW105
SW103
SW101
P100 P100To Ft Control
LCD DV 42LH9088 February 2010
Side Key Assembly P100 Side Key Assembly P100 Voltage and Diode CheckVoltage and Diode Check P100 Resistance Measurements with Key pressed.
CH (Up)CH (Dn)
Volume (+)Volume (-)
KEY
10K Ohms4.8K Ohms1.8K Ohms270.5 Ohms
Pin 3 measured from Gnd
10K Ohms4.8K Ohms1.8K Ohms270.5 Ohms
Pin 1 measured from Gnd
EnterMenuInput
Power
KEY
P100 Voltage Measurements with Key pressed.
CH (Up)CH (Dn)
Volume (+)Volume (-)
KEY
2.24V1.65V
0.906V0.179V
Pin 3 measured from Gnd
2.24V1.65V
0.906V0.179V
Pin 1 measured from Gnd
EnterMenuInput
Power
KEY
P100 Connector “Side Key" to “IR/Intelligent Sensor Board“ P2
GndKey2GndKey1
Label
GndOpenGnd
Open
Diode Check
GndGnd43.3V3.3V3GndGnd23.3V3.3V1
Run STBYPin
P100
LCD DV 42LH9089 February 2010
INVISIBLE SPEAKER SECTIONINVISIBLE SPEAKER SECTION
The 42LH90 contains the Invisible Speaker system.The Full Range Speakers point downward, so there is no front viewable speaker grill or air ports.
Tweeterp/n EAB58536001
Full Rangep/n EAB58534501
Tweeter(High Frequencies)
Main Speaker(Full Range Frequencies)
LCD DV 42LH9090 February 2010
Invisible Speaker System Overview (Tweeters)Invisible Speaker System Overview (Tweeters)
Invisible Speaker has a adhesive surface which adheres to front bezel.
Invisible Speaker Tweetershown separately. The Front (down)
has an adhesive surface which adheres to front bezel. Note, there is
no diaphragm, only voice coil.Outlined
Circle
SpeakerAttachment
post
Cabinet works as a diaphragm.
Elimination of the conventional
speaker.
The front bezel is shown below. Note: the outlined circle is the location for the front adhesive pad on the Invisible Speaker. This prevent the coil from
bouncing off the plastic causing vibrations.
WARNING: Removing the Tweeter will destroy the speaker as shown above. The diaphragm/spider is glued to the
front bezel. When removing, it will tear.
Tweeter p/n EAB58536001
LCD DV 42LH9091 February 2010
Invisible Speaker System OverviewInvisible Speaker System Overview
Invisible SpeakerShown separately. Front (to left) has an adhesive surface which adheres to front bezel. Note, there is
no Cone (Diaphragm), only voice coil.
Spider
Dust Cap with
adhesive
Voice CoilInside
Magnet
Frequency Pass Capacitor
Mount
Mount
Speaker Wires
Speaker Terminals
Tweeter p/n EAB58536001
LCD DV 42LH9092 February 2010
INTERCONNECT DIAGRAM (11 X 17 FOLDOUT) SECTIONINTERCONNECT DIAGRAM (11 X 17 FOLDOUT) SECTION
This section shows the 11X17 foldout thatThis section shows the 11X17 foldout that’’s available in the Paper s available in the Paper and Adobe version of the Training Manual.and Adobe version of the Training Manual.
The Adobe version of this Training Manual allows the viewer to The Adobe version of this Training Manual allows the viewer to zoom in and out making reading of the small text easier.zoom in and out making reading of the small text easier.This Power Point shows a graphical representation of the 11 X 17This Power Point shows a graphical representation of the 11 X 17foldout page so clarity is limited.foldout page so clarity is limited.
P201
SK100
SK101
F100
SMPSSwitch Mode Power Supply
Hot Gnd
Hot Gnd
P203
LN
F101
AC IN
3.15A250V
5A250V
BD101
Bridge Rectifier
Q102
Q101
Q601
Q602
D601
D211
D213
D215
T101
L601
D201
T501
IC501
IC502
IC503
IC102
159.9V in Stand-By190 in Run
42LH90 INTERCONNECT DIAGRAM
SMPS TEST 1: To Force Power Supply On.Disconnect P700 on Main PWB.Jump pin 7,8,9 or 10 (5V) to pin 2 using a 100Ω resistor. (Test Voltage Outputs 12V, and 24V).
SMPS TEST 2: Jump pin 2 to pin 20 (INV-ON).(Backlights and all voltages should turn on).
P1200 "MAIN” to P101 "Front IR / LED
Main Power SW
Side (Key) C
ontrols P101
Front PWB AssemblyIR Receiver
Intelligent Sensor
P100P102
P102 "Front IR / LED PWB to P100 KeysTuner
2PDIM Pin 24 can vary according to type of signal being processed and the OSD Backlight setting. 0.6V 0% to 3.3V 100%. Output from the IC100 Video Processor.
1ADIM Pin 21 Fixed and not used
SpeakersJ1
P100GndKey2GndKey1
Label
GndOpenGndOpen
Diode Check
GndGnd43.2V3.2V3GndGnd23.2V3.2V1
Run STBYPin
Open3.2V0V12Open3.2V3.3V_ST11GndGndGndGnd10Open3.5V3.5VIR9
Open0V0VWarm ST8GndGndGndGnd7
5.1V5.1V5V ST63.2V3.2VKey253.2V3.2VKey14
GndGndGndGnd33.3VSDA2
Open3.3V0.57VSCL1Diode CheckRun STBYLabelPin
POWER On/Off3.2V
STBYLabel
0.57V
OpenOpenOpen
Open
TO TFT MODULE
125V / 3A
CN5 CN4
TO TFT MODULE
UC1
FL1
D8
L1
F1 (12V)
TO TFT MODULE
T-CON(TFT Driver)
Gnd Protect
FL2Gnd Protect
CN1
U11
D7
L2 D9
D10
Q1
U12
U10
Pin 2Pin 4
Pin 56,57,58
Pin 53,54
U5
1) 0V2) 1.19V3) 3.3V
B2.78V E
3.3V
C3.3V
16V
20.5V 14.25
V
-2.4V
12
32
R701R702
R70
4R
705
R70
6
16V26V
27V
26V16V -4.9V3.3VPin 59
Pin 57Pin 3,4,5
Pin 7,826V16V-4.9V3.3V
C74
4R
721
( 12V )
U5
Gnd -4.9V
U5 B+ ( 12V )
3.3VVCC
16V
3.3V
CN2
VDD
1) Gnd2) Gnd3) Gnd4) Gnd
8) 3.34V7) 3.09V6) 3.34V5) 3.34V
FLA
SH
P3500
IC3502Tru-
Motion/Dimming
P3502
IC3502 Operates at
high temperature
P3501
P700
X350025Mhz
IC3503
IC3504
IC3500
Q706
ECB
Q702
IC706
ECB
Q701
L718
L710
IC701
L726
IC705
IC704
IC2
SW3500Not Used
IC801
IC901
IC900
X80012Mhz
IC1
X10012Mhz
IC100Micro/VideoProcessor
Mstar
IC707
L712
IC708
IC1000IC1001
IC101
SW100
ECB
Q100
IC105
IC502
IC600
L607
L606
P1200
EC B Q106
IC1002
Q1200
ECB
IC1203
TU1001 TunerTDVW-H103F
(1)
Analog Video (19)
Tuner 5V_TU (4)
Data (8)Clock (9)
Dig DIF+ (12)Dig DIF- (13)SIF (16)
X100525Mhz
P101N/A
IC1004
D1000
12V LVDSPins 1~4
P600
IC3505
C A1
A2D1223
IC1200
IC1201
D500
C
A1 A2
Q1001
E CB
Q1000
IC1003
IC703
ECB
CA1
A2
ECB
2 31
Q105IC103
IC702IC104
IC102
IC800
IC1202
IC501
Q703
EC B
Q704
EC B
Q705
EC B
IC10723
1
D102
Q600E CB
42LH90MAIN BOARD
Grayed Out Components are on the Back
D1000
D208
D207Q212 Q211
L204
L203IC201
680u
F35
V
C203Q210
Q209
680uF35V
C212
D202
D203Q205 Q204
Q10
Q9
L202
L201
C27
D8
D7Q12 Q11
L4
L3
+
-
+ -
680u
F35
V
C3
+ -
Q202
Q203
680uF35V
-
+
C12
D2
D3
Q5 Q4
L2
L1
680uF35V
-
+
Q2
Q3
F112A/65V
ZD3
CN1
F22A/125V
L5
-
+
680uF35V
C40
CN3
CN4
IC1 IC3
21
322
1
32
IC4 IC15
Q35
Q36
Q37
Q34
Q33
Q32IC8IC9Q31
Q30
Q29
Q28
Q27
IC7IC10
Q38
Q39
Q40
Q41
Q42
IC6IC13
Q43
Q44
Q45
Q46
Q26
Q25
Q24Q23
ZD303ZD304
Q22
IC5
IC14
CN307
CN306
n/c
Q21
Q20
Q19CN305
n/c
Q47
Q48
Q49
Q50
IC301Processor
Y301 (12Mhz)213
221 3
2IC303
IC302
680uF35V
C227 +
-
12345
1.25Vp/p1.76Vp/p
D302
To Backlights
To B
ackl
ight
s
24V CN1 "INVERTER" TO P203 "SMPS"
For Voltages see CN1 Table
P203 "SMPS" TO CN1 "INVERTER"
1Ext_VBR_B same as (P-DIM)
OPENOPEN
OPENGNDGNDGNDGNDGND0.74V
Pin Label14 AGP13 Ext_VBR_B12 ON/OFF11 NC10 GND9 GND8 GND7 GND6 GND
1-5 VIN
OPEN
Diode Check
Pin Label STBY Run Diode Check
14 AGP 0V 0V OPEN
13 1Ext_VBR_B 0V 0.33V-3.2V OPEN
12 ON/OFF 0V 4.65V 1.6V
11 NC 0.47V 1.66V OPEN
10 GND GND GND GND
9 GND GND GND GND
8 GND GND GND GND
7 GND GND GND GND
6 GND GND GND GND
1-5 VIN 0V 24.0V 2.9V
LED Board
M1
M2
M3
M4
M1-M4 (27.5V)
24V
D302 blinks 1Hz OK
For Main board component Voltages see PG 3 of Interconnect Diagram
INVERTER Board
Q19 through Q50Note: Each output driver (switch) has a TP to the left and right
representing a “V” which indicates a Block of LEDs.V34 represents Pin 23 of CN4V33 represents Pin 24 of CN4
Grounding these points when the 27.6V supplies are working will cause the entire Block of Backlight LEDs to turn on.
(100mA to light one block)
P700 "Main" to P201 “SMPS"
For Voltages see P201
1.3V
Open
2.6V
Diode Check
2.9V
2.2V
1.1VGnd
Open
Open
1
19
21
23
2
20
22
24
3,4,5,67,8,9,1011,1213,14
15,1617,18
Gnd
Gnd
Open
Open
Open
12V LVDS Pins 1~4
12V LVDS Pins 48~51(Pin 1)
3.54Vp/p
(Pin 4)3.48Vp/p
(Pin 6)3.46Vp/p
P/N EAT60665101
P201 “SMPS" to P700 "Main"
ncncnc1
Gnd
nc
Diode Check
GndGndGnd
Open5.15V5.15V5V
GndGndGndGnd
0.98V12V0V12V
0.74V24V0V24V
ncncncnc19
Open1.66V0V1 A.DIM21
ncncnc23
Run STBYLabelPin
1.6V4.98V0VPWR-On2
Open4.65V0VINV.ON20
Open0V0VErr Out22
Open3.2V0V2PDIM24
7,8,9,10
11,12
13,14GndGndGndGnd15,16
17,18
nc
3,4,5,6
CN327.5V Line on CN3
Pins 1-2 (Out_M2)Pins 13-14 (Out_M2)Pins 16-17 (Out_M2)Pins 26-29 (Out_M2)Pins 31-32 (Out_M4)Pins 43-44 (Out_M4)Pins 46-47 (Out_M4)Pins 58-59 (Out_M4)
INVERTER CN3-CN4 INFO.CN4
27.5V Line on CN4Pins 1-2 (Out_M3)Pins 13-14 (Out_M3)Pins 16-17 (Out_M3)Pins 26-29 (Out_M3)Pins 31-32 (Out_M1)Pins 43-44 (Out_M1)Pins 46-47 (Out_M1)Pins 58-59 (Out_M1)
42LH90 MAIN (FRONT SIDE) SIMICONDUCTORS
IC101 Serial Flash IC704 +3.3V_FE IC707 +1.8V_MEMC IC1001 +3.3V_PVSB IC3500 +3.3V_Dimming Q100 W/P IC101 Q706 +5V/12VLVDSPin Memory Pin Regulator Pin Regulator Pin +3.3V_FE Pin Regulator Pin Pin Switch[1] 0.05V [1] 0.8V [1] 0.8V [1] 4.94V [1] Gnd B 0V [1] 5.1V[2] 3.2V [2] Gnd [2] Gnd [2] 4.94V [2] 3.3V C 2.5V [2] 0.29V[3] 2.5V [3] 5V [3] 4.92V [3] Gnd [3] 5V E Gnd [3] 11.9V[4] Gnd [4] 7.5V [4] 6.5V [4] 3.4V [4] 5.99V[5] 0V [5] 5V [5] 4.8V [5] 1.25V IC3503 +1.8V Reg Q106 S5/S6 Reset [5] 11.98V[6] 0V [6] 3.3V [6] 1.8V Pin Dimming Pin Mstar [6] 11.98V[7] 3.3V [7] 3.3V [7] 1.8V IC1002 +5V_TU [1] 0.58 B 0V [7] 5.06V
[8] 3.3V [8] 2.1V [8] 4.8V Pin Tuner [2] 1.8V C 3.28V [8] 5.06V[1] 8.92V [3] 3.19V E 0V
IC105 HDCP IC705 +1.26V_VDDC IC708 +1.26V_MEMC [2] 1.88V Q1200 IR RS232Pin EEPROM Pin Regulator Pin Regulator [3] 5.04V IC3504 Dimming Q702 INV_ON Pin Buffer[1] Gnd [1] 0.8V [1] Gnd [4] 0V Pin EEPROM Pin Inverter B 0.634V[2] Gnd [2] Gnd [2] 0.8V [5] Gnd [1] Gnd B 0.05V C 0.97V[3] 3.29V [3] 5V [3] 1.26V [2] Gnd C 4.66V E Gnd[4] Gnd [4] 6V [4] 1.26V IC1203 SPIF Optical [3] Gnd E Gnd[5] 3.3V [5] 3.2V [5] 1.8V Pin Audio [4] Gnd D1000 Speed Up Reset[6] 3.3V [6] 1.2V [6] 5V [1] 1.58V [5] 3.3V Pin IC1004[7] 0V [7] 1.26V [7] 1.26V [2] 3.2V [6] 3.3V C 3.4V
[8] 3.3V [8] 5V [8] 5V [3] Gnd [7] 0V A 3.38V[4] 1.61V [8] 3.3V
IC701 +1.8V_DDR IC706 5V_EXT IC1000 +1.26V_PVSB [5] 3.21VPin Regulator Pin Memory Pin Regulator[1] 0V [1] 0.8V [1] 0V[2] 3.2V [2] Gnd [2] 3.39V[3] 3.2V [3] 12V [3] 3.4V[4] n/c [4] 9.6V [4] 0V[5] n/c [5] 5V [5] 0V[6] 1.8V [6] 4.97V [6] 1.21V[7] 0.8V [7] 4.97V [7] 0.8V
[8] Gnd [8] 1.9V [8] Gnd
42LH90 MAIN (BACK SIDE) SIMICONDUCTORS
IC103 Reset Gen IC703 +3.3V_ST IC1200 RGB IC1202 USB +5V Q703 5V Switch Q1001 Tuner VideoPin Mstar IC100 Pin Regulator Pin EEPROM Pin Switch Pin Control Pin Buffer[1] Gnd [1] 0V [1] Gnd [1] 4.95V B 0.6V B 3.09V[2] 0V [2] 1.8V [2] Gnd [2] Gnd C 0.03V C 0V[3] 3.3V [3] 3.21V [3] Gnd [3] 3.21V E Gnd E 3.72V
[4] Gnd [4] 4.95VIC104 RGB (PC) [5] 4.82V [5] 0V Q704 1st 12V LVDS D102 Audio Mute
Pin EEPROM IC800 SPI Flash [6] 4.82V [6] 4.95V Pin Switch Control Pin Routing[1] Gnd Pin [7] 4.82V B 0.05V A1 0.047V[2] Gnd [1] 0.12V [8] 4.82V IC3505 Reset Gen C 0.65V C 0.089V[3] Gnd [2] 1.13V Pin for IC3502 E Gnd A2 0V[4] Gnd [3] 3.26V IC1201 RS232 [1] 3.3V[5] 3.22V [4] Gnd Pin Rx/Tx [2] Gnd Q705 2nd 12V LVDS D500 Shunt for[6] 3.22V [5] 0.06V [1] 3.3V [3] 3.22V Pin Switch Control Pin IC501[7] 0V [6] 1.2V [2] 5.56V B 0.65V A1 3.25V[8] 3.22V [7] 3.27V [3] 0.02V Q105 PWR On Delay C 0.0V C 3.12V
[8] 3.27V [4] 0.03V Pin Q2405 E Gnd A2 0VIC107 Power Det [5] 5.46V B 0V
Pin Gen IC1003 9V Reg [6] 5.5V C 1.95V Q1000 Tuner SIF D1223 5V Routing[1] Gnd Pin to IC1002 [7] 5.5V E Gnd Pin Buffer Pin for IC1200[2] 3.9V [1] 12V [8] 0V B 2.4V A1 0V[3] 3.28V [2] Gnd [9] 3.29V Q600 Audio Mute C 0V C 4.82V
[3] 8.9V [10] 3.24V Pin Switch E 3.85V A2 5.11VIC702 +3.3V_ST For Tuner Voltage 5V [11] 0.02V B 0.08V
+3.3V_AVDD_MPLL [12] 3.29V C 3.26VPin Regulator [13] 0V E Gnd[1] Gnd [14] 5.5V[2] 3.29V [15] Gnd[3] 5.11V [16] 3.29V
42LH90 LVDS P3500 WAVEFORMS
42LH90 P3500 LVDS CABLE WAVEFORMS:Waveforms taken using SMTP Color Bar input.All readings give the Scale 10mV and Time Base related to scope settings. Top waveform in each image gives a slower rate, 2us per division. Outlined area is shown in the bottom waveform at 500ns per division time base.
Pin 11 Pin 12 Pin 16
Pin 24
Pin 35
Pin 38Pin 37
Pin 30
Pin 23
Pin 20
Pin 13 Pin 14
Pin 17 Pin 21
Pin 27 Pin 28
Pin 36Pin 32
Pin 39 Pin 40
Pin 19 Pin 22
Pin 29
Pin 33
42LH90 LVDS P3502 WAVEFORMS
42LH90 P3502 LVDS CABLE WAVEFORMS:Waveforms taken using SMTP Color Bar input.All readings give the Scale 10mV and Time Base related to scope settings. Top waveform in each image gives a slower rate, 2us per division. Outlined area is shown in the bottom waveform at 500ns per division time base.
Pin 3
Pin 12
Pin 15
Pin 22
Pin 29 Pin 30
Pin 27
Pin 16
Pin 8Pin 4 Pin 5 Pin 6
Pin 11Pin 9 Pin 13 Pin 14
Pin 19 Pin 20 Pin 21
Pin 28Pin 24 Pin 25
Pin 31 Pin 32