42LG60-Fall 2008-v25 - Diagramas dediagramas.diagramasde.com/otros/LG Flat TV 42LG60...

42LG6042LG60

Direct View LCD

LCD DV 42LG602

OUTLINEOUTLINE

• Main Board

• T-CON Board• Control Board

• Ft Control Board

Circuit Board Operation, Troubleshooting of :• Switch mode Power Supply

Section 1

Section 2

Contact Information, Preliminary Matters, Specifications,LCD Overview, General Troubleshooting Steps, Signal Distribution, Disassembly Instructions and Voltages

LCD DV 42LG603

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.

Overview of Topics to be DiscussedOverview of Topics to be Discussed

LCD DV 42LG604

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 42LG605

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 42LG606

CONTACT INFORMATIONCONTACT INFORMATION

Customer Service (and Part Sales) (800) 243-0000

Technical Support (and Part Sales) (800) 847-7597

USA Website (GCSC) aic.lgservice.comCustomer Service Website us.lgservice.com

LG CS Academy lgcsacademy.com

LG Web Training lge.webex.com

Published March 2009 by LG Technical Support and Training

LG Electronics Alabama, Inc. 201 James Record Road,

Huntsville, AL, 35813.

LCD DV 42LG607

Safety & Handling Regulations

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…

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

TroubleshootingSECTION 1: SECTION 1: LCD OVERVIEWLCD OVERVIEW

LCD DV 42LG608

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 42LG609

This section of the manual will discuss the specifications of the 42LG60“Thin” LCD Direct View Display Panel.

42LG60 Product Information42LG60 Product Information

Side View

LCD DV 42LG6010

Basic SpecificationsBasic 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

LCD DV 42LG6011

Basic SpecificationsBasic Specifications

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.

LCD DV 42LG6012

Remote ControlRemote Control

1 2 3

4 5 6

7 8 9

0

VOL CH

FAV

MUTE

PAGE

LG

TOP PORTION

BOTTOM PORTION

LCD DV 42LG6013

Accessing the Service MenuAccessing the Service Menu

REMOTETOP PORTION

SIDE KEYS

To access the Service Menu.1) Turn the Set On2) 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, enter0000

LCD DV 42LG6014

Side Input Jacks

Rear and Side Input JacksRear and Side Input Jacks

Main PWB

Orientation

Rear Input Jacks

LCD DV 42LG6015

Side Input Jacks

Software release 7/10/08Software release 7/10/08

USB

Service Bulletin: 0IVL20080332Current Software Release

LG6061-MERGE-LU-FHD128-v0315.epk

Symptoms1) When tuned to CADTV 1-1, TV Set Locks-up

(Frozen, will not respond to the remote or Video/Audio).2) DTV Closed captions Lock-up on Channel 20 in

Washington DC (DTVCC Service1 On => VideoFreezes or TV set reboots).

Update the firmware using a USB flash drive. For warranty work, you have to write this service bulletin number 0IVL20080332 in the remark or description cell.

LCD DV 42LG6016

42LG60 Product Dimensions42LG60 Product Dimensions

LCD DV 42LG6017

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.

DISASSEMBLY SECTIONDISASSEMBLY SECTION

LCD DV 42LG6018

This section of the manual will discuss troubleshooting.

Upon completion of this section the Technician will have a better understanding of how to diagnosis and resolve problems.

TROUBLESHOOTING SECTIONTROUBLESHOOTING SECTION

LCD DV 42LG6019

Removing the Back CoverRemoving the Back Cover

The Stand does not need to be removedRemove the 13 screws indicated.

Pay attention to the size and type of screwas there are many different types.

Putting in the improper screw when reassembling may Cause damage.

LCD DV 42LG6020

Circuit Board LayoutCircuit Board Layout

POWER SUPPLY Main “Digital”

Control “Logic”

SideInputs

T-CON EAT56803901Shield Removed

Touch LEDAnd Ft Control

BacklightPower Connection

BacklightPower Connection

LVDSCables

LVDS Cable

SideControls

LCD DV 42LG6021

Backlight InformationBacklight Information

Back View 18 Bulbs

Power Supply with Ballast

To Backlights Over 1.2KV

58Khz

EEFL (External Electrode Fluorescent Lamp)LOW COST Large number of lamps driven by a single inverter

2.8V~3.1V RMS

LCD DV 42LG6022

CCFL (Cold Cathode Fluorescent Lamp) EEFL (External Electrode Fluorescent Lamp)

V

I

StatingVoltage

OperatingVoltage

V

I

Starting&

OperatingVoltage

......

...

Simple structureComplicated structure

Simple structure, Low price

Low CostLamp manufacturing processLamp assembly structure

Large number of Lamp Drive by single inverter

Introducing EEFL

LCD DV 42LG6023

CCFL (Cold Cathode Fluorescent Lamp)

Introducing EEFL Long Life Time

ElectrodeGlass Bead

Kov

Lead

: Hg

: electron

EEFL (External Electrode Fluorescent Lamp)

External electrodePhosphor

: Hg

: electron

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

LCD DV 42LG6024

Power Supply (SMPS) PWB LayoutPower Supply (SMPS) PWB Layout

P2

AC INP402

P401

Ballast Section

To Main

P401 and P402TO BACKLIGHT CONNECTORS

INPUT AC 100V ~ 240V (50/60Hz) 3A

OU

TPU

T St-by 5.2V (5A) 12V (2A) 16.5V (1.3A)P401-P402 950V / 135mA

MODEL PLHL-T715A

F1018A/250V

AC IN

F7005A/250V

335V

Heat Sink isHot Ground

Shock Hazard

LCD DV 42LG6025

Power Supply Control SignalsPower Supply Control Signals

LCD DV 42LG6026

Power Supply Power Supply Backlight Drive Backlight Drive Signal EffectsSignal Effects

PWMDIMmanipulates

the Burst Triangle

Oscillator in the ballast drive IC.

ADIM also manipulates

the Burst Triangle

OscillatorBut it is not

used.

LCD DV 42LG6027

Power Supply PWB Test (1Power Supply PWB Test (1STST Test All But Backlights)Test All But Backlights)

The Power Supply “MUST” be producing STAND-BY +5V.

P2 Connector disconnected from the Main PWBAC: Not applied when adding jumpers. Applied when making test.

(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 +16VPins 5 and 6 for +12V

LCD DV 42LG6028

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.

Power Supply PWB Test (2Power Supply PWB Test (2ndnd Test All Including Backlights)Test All Including Backlights)

P2 Connector disconnected from the Main PWB. Apply AC after adding jumpers.

LCD DV 42LG6029

Power Supply Ballast Board Field Problem

T701

Long leads from T701 are arcing through the insulator to ground

Mounting Tabs may be bent

T701

Back Side of Power Supply PWB

LCD DV 42LG6030

Power Supply Connector P2 Odd Pins Voltage and ResistancePower Supply Connector P2 Odd Pins Voltage and Resistance

Resistance taken in Diode Mode with Connectors Removed

OL3.2V0VSEL23

OL1.68V0.1VADIM21

OL2.86V0VPWR19

OL3.3V3.19VERR17

0VGndGndGnd15

0VGndGndGnd13

1.49V5.15V5V5V11

1.49V5.15V5V5V9

0VGndGndGnd7

1.32V11.8V0V12V5

0VGndGndGnd3

0.94V16V0V16V1

Diode CheckRun STBYLabelPin

P2 Odd "SMPS" to P801 "Main PWB"

Not Used

Not Used

LCD DV 42LG6031

Power Supply Connector P2 Even Pins Voltage and ResistancePower Supply Connector P2 Even Pins Voltage and Resistance


OL0V0VSYNC24

OL3.38V0VPDIM22

OL3.29V0VINV20

1.85V4.57V4VACD18

0VGndGndGnd16

0VGndGndGnd14

1.49V5.15V5.15V5V12

1.49V5.15V5.15V5V10

0VGndGndGnd8

1.32V11.8V0V12V6

0VGndGndGnd4

0.94V16V0V16V2


P2 Even "SMPS" to P801 "Main PWB"

PDIM Pin 22 can vary according to OSD Backlight setting. 0.9V 0% to 3.3V 100%Not Used

LCD DV 42LG6032

SMPS PWB Connector P401 or P402 Voltage and ResistanceSMPS PWB Connector P401 or P402 Voltage and Resistance


P401 or P402 Backlights

0V>1Kvac0V20V>1Kvac0V1

Diode CheckRun STBYPin

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 connectorsto the Ballast and a 17.5μ sec sine waveform should be measured this would be

an indication that the ballast supply is functioning.

LCD DV 42LG6033

Control PWB IC101 InfoControl PWB IC101 Info Troubleshooting

The Control PWB contains the MICRONAS chip IC101. This IC is a Full-HD Rate Converter with Motion Blur Removal and Film De-Juddering 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

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 PullDown was developed to eliminate this problem. Frame Rate Conversion (Real Cinema) eliminates the need for 3:2 Pull Down.

Motion Blur Removal increases the video frames by Interpolating a new image frame between each original frame (Motion Estimated Data Insertion) MEDI.

LCD DV 42LG6034

TruMotion 120Hz ( Vector Based Motion Compensation)TruMotion 120Hz ( Vector Based Motion Compensation)

Conventional (60Hz)

True Motion (120Hz)

Conventional

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).

LCD DV 42LG6035

24p Real Cinema

A A A A A B B B B B C C C C C5:5 TruCinema

(120Hz)

Conventional(60Hz)

Scene A Scene B Scene C

A B C

A A A B B C C C

24P(Film)

1/24[sec]

Judder1/60[sec]

1/120[sec]

Time

An irregular sequence of frames in a movie or video image

Judder

Frame Rate Conversion eliminates the need for 3:2 Pull Down Conversion

LCD DV 42LG6036

Control PWB RemovalControl PWB Removal Troubleshooting

Disconnect P101, P103 and P104 LVDS CablesCAUTION: When removing LVDS Cables, be careful. Press the release Tabs to avoid damage to PWB or to the Cable itself.

LVDS ConnectorsPress in from the sides and lift out.

LCD DV 42LG6037

Control PWB (WITH SHIELD)Control PWB (WITH SHIELD) Troubleshooting

LCD DV 42LG6038

Control PWB (WITHOUT SHIELD)Control PWB (WITHOUT SHIELD) Troubleshooting

IC108 IC109 IC110

X101

LCD DV 42LG6039

Control PWB Regulators Identified and VoltagesControl PWB Regulators Identified and Voltages

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)

(1) (1) (1)

LCD DV 42LG6040

Control PWB Crystal X101 CheckControl PWB Crystal X101 Check

Control PWBX101 Location

1.7Vp/p20.25Mhz

Only when set is on

LCD DV 42LG6041

TT--CON (TFT DRIVE) PWB CON (TFT DRIVE) PWB

LCD Controller BoardThe 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 connectorsCN4 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 introubleshooting as a quick indication of a loss of supply and or a Boot Up problem.

T CON IC TL22970D

LG Philips LCD Drive IC

UC1

U15

U16 F1

Next Slidegives greater layout details

LCD DV 42LG6042

TT--CON (TFT Drive) PWB (Shield Removed) CON (TFT Drive) PWB (Shield Removed) p/np/n EAT56803901 EAT56803901

U15

U16

LD1

US1

F1

CN5 CN4

CN1 CN2

UC1

ToControl

To TFT Panel To TFT Panel

Remember to replace screws for ground

purposes if turning on the set.

LCD DV 42LG6043

TT--CON (TFT DRIVE) PWB CHECKSCON (TFT DRIVE) PWB CHECKS

T-CON PWB

0V

3.2V

1.8V

US1

LD1

Use LD1 to determine ifThe boot up sequence ofThe T-CON is OK.This LED will turn bright BlueShortly after power is applied then go out shortly after backlights illuminate if all is OK.

Power Off Power 1st OnAnode 0VCathode 0V

Anode 11.6VCathode 0V

Power OnAnode 11.6VCathode 9.5V

LED OFF LED ON LED OFF

Check the Regulator US1 for Correct Voltage

Check FuseF1 for 12V

F1

CN1

LCD DV 42LG6044

Main PWBMain PWB

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

LCD DV 42LG6045

Main PWB LayoutMain PWB Layout Troubleshooting42LG60

VIDEO PROCESSOR IC100 RUNS HOT, THIS IS NORMAL.

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.

LD803

1 16

LD803 3.3V-BCM OK

LCD DV 42LG6046

Main PWB (Back View) Regulator LayoutMain PWB (Back View) Regulator Layout

BCM ResetIC100 Video Processor

IC805

IC400

IC400

IC405

IC4053.29V

0V0.6V

3.31V0V

0.6V

123

SBY RUN IC8100V0V

0.3V

0V1.8V

3.31V

123

SBY RUN

0.4V0V

0.4V

3.37V0V

3.39V

123

SBY RUN

IC101

IC8020V

0.3V0V

5V3.3V

0V

123

SBY RUN

IC802

Q901 Q902 LVDS 12V Switch ControlLVDS 12V SwitchOutput 5~8 (12V)

IC810

IC805 0.V0V0V

0.4V0.1V

3.3V5V0V

3.39V1.2V

12345

SBY RUN3.3V BCM

LCD DV 42LG6047

2.4Vp/p24Mhz

Main PWB X400 and X200 CheckMain PWB X400 and X200 Check

Main PWBX200 Location

780mVp/p54Mhz

Main PWBX400 Location

Only when set is on

Set on or off

Use left side of L206

MAIN PWB

X200

X400

Microprocessor Crystal

Video Processor Crystal

LCD DV 42LG6048

Main PWB LD803 CheckMain PWB LD803 Check

Main PWBLD803 Location

MAIN PWB

LD803

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.

LCD DV 42LG6049

Main PWB Tuner Video and SIF Output Check Pin LocationMain PWB Tuner Video and SIF Output Check Pin Location

For Easy Access, pop the shield off the tuner

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 14 Audio SIF

Pin 16 Composite Video

Pin 14 Pin 16

Pin 3 Tuner B+ (5V)

Pin 1

LCD DV 42LG6050

MAIN PWB

Main PWB Tuner Video and SIF Output CheckMain PWB Tuner Video and SIF Output Check

Tuner Location

1Vp/p 20uSec rate

Pin 16 “Video”Signal

Pin 14 “SIF”Signal

850mVp/p 20nSec rate

USING SMTE COLOR BAR SIGNAL INPUT

LCD DV 42LG6051

Main PWB LVDS P900 Output CheckMain PWB LVDS P900 Output Check

P900Location

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.

MAIN PWB

Pin 11

Pin 16This is just a sample

of two pins on the LVDS.There are 24 pins carrying video.

LCD DV 42LG6052

Main PWB Connector P801 Odd Pins Voltage and ResistanceMain PWB Connector P801 Odd Pins Voltage and Resistance


Pin 17 ERR is not used.Pin 21 ADIM is a fixed voltage.Pin 23 SEL is not used.

P801 CONNECTOR "Main" Odd Pins to P2 "SMPS PWB"

OL3.2V0VSEL23

OL1.68V0.1VADM21

1.1V2.86V0VPWR19

2.89V3.3V3.19VERR17

GndGndGndGnd15

GndGndGndGnd13

1.47V5.15V5V5V11

1.47V5.15V5V5V9

GndGndGndGnd7

3V11.8V0V12V5

GndGndGndGnd3

OL16V0V16V1


LCD DV 42LG6053

Main PWB Connector P801 Even Pins Voltage and ResistanceMain PWB Connector P801 Even Pins Voltage and Resistance


P801 CONNECTOR "Main" Even Pins to P2 "SMPS PWB"

OL0V0VSYNC24

OL3.38V0VPDS22

1.8V3.29V0VSTV20

OL4.57V4VAC Det18

GndGndGndGnd16

GndGndGndGnd14

1.47V5.15V5.15V5V12

1.47V5.15V5.15V5V10

GndGndGndGnd8

3V11.8V0V12V6

GndGndGndGnd4

OL16V0V16V2


Pin 22 PDIM can vary according to OSD Backlight setting. 0.9V 0% to 3.3V 100%Pin 24 is not used

LCD DV 42LG6054

Main PWB Connector P401 Voltage and ResistanceMain PWB Connector P401 Voltage and Resistance


P401 CONNECTOR "MAIN PWB" to "Front PWB Assy"

Gnd0V0VGnd15

OL0V0Vn/c14

OL0V0VSPKP13

Gnd0V0VGnd12

OL0V0VSPKN11

1.35V3.92V3.92VIR10

Gnd0V0VEYEQ-Reset9

1.47V5V5V5V8

0.71V3.3V3.3V3.3V7

1.85V3.3V3.3VKey26

1.85V3.3V3.3VKey15

Gnd0V0VGnd4

Gnd0V0VGnd3

2.26V3.25V3.25VEYEQ-SDA2

2.26V3.25V3.25VEYEQ-SCL1

Diode CheckRun STBYLABELPin

LCD DV 42LG6055

Main PWB Connector P800 and P501 Voltage and ResistanceMain PWB Connector P800 and P501 Voltage and Resistance


P800 CONNECTOR "Main" Odd Pins to P102 "Control PWB"

2.58V8V0V4

2.58V8V0V3

2.58V8V0V2

2.58V8V0V1

Diode CheckRunSBYPin

P501 CONNECTOR "Main" to "Speakers"

1.35V0V3.3V13

1.29V3.3V3.3V12

1.24V3.3V3.3V11

1.28V3.3V3.3V10

1.39V3.3V3.3V9

Gnd0V0V8

OL16V0V7

OL16V0V6

Gnd0V0V5

0.55V3.3V0.5V4

Gnd0V0V3

0.8V5V0V2

0.8V5V0V1


Use speaker out to test for defective Audio Amp

IC501

LCD DV 42LG6056

Main PWB Connector P900 Main PWB Connector P900 ““Odd PinsOdd Pins”” Voltage and ResistanceVoltage and Resistance

Resistance taken in Diode Mode with Connectors

Removed

P900 CONNECTOR "Main" Odd Pins to P104

"Control PWB"

OL0V0V39

1V1.16V0V37

1V1.16V0V35

1V1.07V0V33

1V1.14V0V31

1V1.12V0V29

1V1.14V0V27

2.98V3.15V0.5V25

OL0V0V23

1V1.14V0V21

1V1.16V0V19

1V1.11V0V17

1V1.12V0V15

1V1.11V0V13

1V1.14V0V11

1V3.3V0.47V9

Gnd0V0V7

Gnd0V0V5

OL11.7V0V3

OL11.7V0V1


Video Signal Pins

Video Signal Pins

Switched LVDS 12V

SCL

n/c

n/c

LCD DV 42LG6057

Main PWB Connector P900 Main PWB Connector P900 ““Even PinsEven Pins”” Voltage and ResistanceVoltage and Resistance


P900 CONNECTOR "Main" Even Pins to P104

"Control PWB"

Gnd0V0V40

1V1.07V0V38

1V1.07V0V36

1V1.13V0V34

1V1.07V0V32

1V1.09V0V30

1V1.14V0V28

3V3.3V0V26

1.28v3.25V0V24

1V1.05V0V22

1V1.07V0V20

1V1.11V0V18

1V1.05V0V16

1V1.11V0V14

1V1.14V0V12

1V3.3V0V10

Gnd0V0V8

Gnd0V0V6

OL11.7V0V4

OL11.7V0V2


Video Signal Pins

Video Signal Pins

Switched LVDS 12V

SDA

FRC Reset

Resistance taken in Diode Mode with

Connectors Removed

LCD DV 42LG6058

Front Touch and LED PWB LayoutFront Touch and LED PWB Layout

J1

Front PWBAssembly

To Main

LCD DV 42LG6059

Front Touch LED Connector J1 Voltage and ResistanceFront Touch LED Connector J1 Voltage and Resistance

J1 CONNECTOR “Ft LED Touch" to J2 “Ft Control PWB"

3.3V3.3V90V0V8

3.3V3.3V70V0V60V0V50V0V45V5V3

3.3V3.3V23.3V3.3V1Run STBYPin

With all Connectors Removed, no ground return.

LCD DV 42LG6060

Front PWB Assembly LayoutFront PWB Assembly Layout

J3

J2

J1

To Front Touch LED PWB

To Main PWB

To Side KeyControl PWB

Right Tweeter

The Intelligent Sensor and IR Sensor are

located on the front of this PWB

Light Diffuser for the Intelligent Sensor

Light Diffuser for the Intelligent Sensor

IR Sensor

LCD DV 42LG6061

Front Control Connector J1 Voltage and ResistanceFront Control Connector J1 Voltage and Resistance


J1 CONNECTOR "Front Control PWB" to "MAIN PWB" P401

0V0VGnd15

0V0Vn/c14

0V0VSPKP13

0V0VGnd12

0V0VSPKN11

3.92V3.92VIR10

0V0VEYEQ-Reset9

5V5V5V8

3.3V3.3V3.3V7

3.3V3.3VKey26

3.3V3.3VKey15

0V0VGnd4

0V0VGnd3

3.25V3.25VEYEQ-SDA2

3.25V3.25VEYEQ-SCL1

Run STBYLABELPin

LCD DV 42LG6062

Front Control Connector J2 Voltage and ResistanceFront Control Connector J2 Voltage and Resistance

J2 CONNECTOR “Ft Control” to “Ft Touch LED" J1

3.3V3.3V90V0V8

3.3V3.3V70V0V60V0V50V0V45V5V3

3.3V3.3V23.3V3.3V1Run STBYPin


J3 CONNECTOR “Ft Control” to “Side Controls" P100

0V0V43.3V3.3V30V0V2

3.3V3.3V1Run STBYPin

LCD DV 42LG6063

Side Control Key PWB LayoutSide Control Key PWB Layout

To FrontControl PWB

P100

LCD DV 42LG6064

Side Control Connector P100 Voltage and ResistanceSide Control Connector P100 Voltage and Resistance

P100 CONNECTOR “Side Control” to “Front Control" J3


0V0V43.3V3.3V30V0V2

3.3V3.3V1Run STBYPin

LCD DV 42LG6065

Invisible Speaker System LayoutInvisible Speaker System Layout

RightTweeter

LeftTweeter

Right Speaker Box

LeftSpeaker Box

LCD DV 42LG6066

Speaker Box Assembly RemovedSpeaker Box Assembly Removed

ToTweeters

Speaker BoxRemoved

To Remove Speaker Box, remove the 4 screws show in circles remove wire harness.Carefully disconnect both Tweeters. Unplug P500 from Main PWB.

P900P800

P401P501

P801

TUNERATSC/QAM/

NTSC

IC100BCM

IC302

IC300

IC303

IC301 IC404

IC1000

X200 (54Mhz)

IC800IC806

IC402

IC503

IC701

IC600 IC820

42LG60 CIRCUIT INTERCONNECT DIAGRAM

CN5 CN4

TFT-Drive (T-CON)CN1 CN2

P103 P104

CONTROL P102

P101

LVDS

POWER SUPPY J1

J2

J1J3

P2

LVDS

Ft. TOUCHLED/Push Sw

SpkSpk

Ft. PWB Assy.

AC In

LeftBacklight

Plug

RightBacklight

Plug

TFT PANEL

IC101IC103

IC102

IC108 IC109 IC110

5 (2.5V)4 (0V)3 (0V)2 (3.3V)1 (3.37V)

5 (0V)4 (1.79V)3 (0V)2 (3.36V)1 (3.29V)

5 (1.2V)4 (1.3V)3 (0V)2 (3.37V)1 (3.29V)

X10120.25Mhz

UC1LD1U15

U16

US10V

3.2V 1.8V

3A 125V11.6V

SET 0FFLED OFF

SET ONLED OFF

LD1 Blue LED TFT Drive PWB Check

AnodeCathode

0V0V

BOOT OKLED ON

AnodeCathode

11.6V0V

AnodeCathode

11.6V9.5V

F1018A 250V

ACF700

5A 250V335V

Backlight pulse over 1000V p/p (45KhZ)

IC500

X400

IC407

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.

Side Control Keys

MAIN PWB

P200Not Used

F1

IC900

IC807IC1201

IC304

IC1200IC202

LD8033.3V BCM

IC805OK LED

IC501

Pin 1 ~ 16

Q400E B

24Mhz

P2

3

1

7

5

11

9

15

13

19

17

23

21

4

2

8

6

12

10

16

14

20

18

24

22

10K

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.

PDIM Pin 22 can vary according to OSD Backlight setting. 0.9V 0% to 3.3V 100%

P2 "SMPS" to P801 "Main PWB"

Pin Label STBY Run 1 16V 0V 16V3 Gnd Gnd Gnd5 12V 0V 11.8V7 Gnd Gnd Gnd9 5V 5V 5.15V11 5V 5V 5.15V13 Gnd Gnd Gnd15 Gnd Gnd Gnd17 ERR 3.19V 3.3V19 PWR 0V 2.86V21 ADIM 0.1V 1.68V23 SEL 0V 3.2V

Pin Label STBY Run 2 16V 0V 16V4 Gnd Gnd Gnd6 12V 0V 11.8V8 Gnd Gnd Gnd10 5V 5.15V 5.15V12 5V 5.15V 5.15V14 Gnd Gnd Gnd16 Gnd Gnd Gnd18 ACD 4V 4.57V20 INV 0V 3.29V22 *PDIM 0V 3.38V24 SYNC 0V 0V

Odd Pins

Pins 17, 23 and 24 Not Used

IC109IC108 IC110

1 16

*Q901*Q902

*IC400

*IC802

*IC810

*IC405

*Grayed out components on the back

Function Pin Volts Function Pin Volts Name Function Pin Volts Function Pin VoltsIn from IC806 1 8.95V In 6,7,8,10 5V 1 0V Source C ST-5VOn/Off 2 3.3V Out 1,2,3,4,5 2.6V Out 2 3.3V Control B RL-ON (PWR)Out (+5V-TU) 3 5.0V On/Off 17 Power Control In 3 5V Gnd E 0Vn/c 4 0.0VGnd 5 0.0V

Function Pin Volts Function Pin VoltsIn 2 5V In 1 3.3VST-MICOM

Function Pin Volts Function Pin Volts Name Out 4 3.3V (A3.3V-BCM) Gnd 2 0.0VIn (+12V) 1 11.6V In 6,7,8,10 5V On/Off 1 Power Control-3.3V Out 3 Low to High to B Q400Gnd 2 0.0V Out 1,2,3,4,5 1.2VOut 3 9V On/Off 17 Power Control

Function Pin Volts Function Pin VoltsIn 3 3.3V from IC802 Source C 12V

Function Pin Volts Out 2 1.8V (+1.8V-NTP) Control B LVDS-Panel-Control1 0V Gnd 1 Gnd E 0V

Out 2 3.3V Function Pin Volts NameIn 3 5V In 3 5V ST_+5V

Out 2 3.3V Reset Function Pin Volts Function Pin VoltsGnd 1 0V Gnd In C ST-5V Source 1, 3 12V

Control B RL-ON (PWR) Control 2, 4 Low from Q902Gnd E 0V Output 5~8 12V

Q901 (On Back)12V LVDS On control to P900 Pins 1~4

IC404 uP 3.3V3.3VST-MICOM

IC404

IC806 IC8201.2V Switching Regulator A1.2V-BCM

Use L014 left side to test output

Q802 (On Back)5V Switch control to Q801

IC8072.6V Switching Regulator A2.6V-BCM

Use L801 left side to test outputUse any top pin of IC807 to test input

Use any top pin of IC820 to test input

9V Regulator

3.3V Regulator

Q801 (On Back)5V Switch

IC405 uP Reset (On Back)Reset by Charge of C431

IC802 (On Back)3.3V Regulator

Q902 (On Back)

FRONT SIDE OF MAIN PWB

IC810 (On Back)1.8V Switching Regulator +1.8V-NTP

3.3V Switching Regulator A3.3V-BCMIC805 (On Back)

IC800BACK SIDE OF MAIN PWB

5V Switching Regulator

12V LVDS control to Q901

Gnd

Gnd

0V

P100

See back side of page for Waveforms forP900 using SMTE Color bar as the Input.

Tuner Pin 16 SMTE Color bar In

uP5V Pin 3Video Pin 16Audio SIF Pin 14

TUNERBallastSection

*IC805

ResetBCM

P402

P401

Scope test point

Tweeter Tweeter

Pin 24 Pin 23

LG

Pin 21 is a Fixed Voltage

F700 90V in Stand-By

LVDS CABLE P900 FROM MAIN PWB TO CONTROL PWB P101 USING SMTP COLOR BAR INPUT

LAST TWO WAVEFORMS ARE FROM THE TUNER

Measurements +/- 5%

LCD DV 42LG6074

Power Supply PWB RemovalPower Supply PWB Removal

Disconnect P2, AC In, P402 and P402Remove the 6 screws indicated below in red.

LCD DV 42LG6075

MAIN PWB RemovalMAIN PWB Removal

Disconnect P401, P501, P800, P801 and P900Note: 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.

LCD DV 42LG6076

Control PWB RemovalControl PWB Removal

Disconnect P101, P102 P103 and P104Remove the 4 screws indicated below in red.

LVDS CablesPress in from sidesto release

LCD DV 42LG6077

TT--CON (TFT Drive) PWB RemovalCON (TFT Drive) PWB Removal Troubleshooting42LG60

Disconnect CN1, CN2, CN3 and CN4Remove the 3 screws indicated below in red.

42LG6042LG60Direct View LCD

This concludes the 42LG60training session.

42LG60-Fall 2008-v25 - Diagramas dediagramas.diagramasde.com/otros/LG Flat TV 42LG60...

Documents

Transcript of 42LG60-Fall 2008-v25 - Diagramas dediagramas.diagramasde.com/otros/LG Flat TV 42LG60...