LG 42LE5500 Schematic

1080P

Published October 8th, 2010

Direct View LCD

Training

42LE5500

42LE5500

LED Backlights

LCD-DV Troubleshooting

42" Class Full HD 1080P

LCD TV (42" diagonally)

OUTLINE

OUTLINE

Preliminary Section:

Disassembly Section: Removal of Circuit Boards

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

Troubleshooting Section:

• Switch Mode Power Supply with LED Backlight Driver Board

• Main Board

• Ft Control Board

• Soft Touch Keys

• Speakers

Board Operation Troubleshooting of :

2

October 2010 LCD TV 42LE5500

Overview of Topics to be Discussed

Overview of Topics to be Discussed

42LE5500 LCD Direct View Display

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

Section 1

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.

3

October 2010 LCD TV 42LE5500

IMPORTANT SAFETY NOTICE

IMPORTANT SAFETY NOTICE

CAUTION

CAUTION

Preliminary Matters (The Fine Print)

Preliminary Matters (The Fine Print)

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.

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.

4

October 2010 LCD TV 42LE5500

Regulatory Information

Regulatory Information

ESD Notice

ESD Notice

(Electrostatic Static Discharge)

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.

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.

(Electrostatic Static Discharge)

5

October 2010 LCD TV 42LE5500

LG Contact Information

LG Contact Information

Customer Service (and Part Sales) [phone]
Technical Support (and Part Sales) [phone]
USA Website (GSFS) http://gsfs-america.lge.com
Customer Service Website http://www.us.lgservice.com
Knowledgebase Website http://lgtechassist.com
LG Web Training https://lge.webex.com
LG CS Academy http://ln.lge.com/ilearn

LCD-DV:

PLASMA:

PDP Panel Alignment Handbook, Schematics with Bookmarks

32LG40, 32LH30, 37LH55, 42LG60, 42LG70, 42LH20, 42LH40, 42LH50, 42LH90, 42SL80,
47LG90, 47LH85, 42LE5500, 47LE8500

42PG20, 42PJ350, 42PQ20, 42PQ30, 50PG20, 50PJ350, 50PK250, 50PK750, 50PS80,
50PS60, 60PK750, 60PS11, 60PS60, 60PS80

Also available on the Plasma Page:

Plasma Control Board ROM Update (Jig required)

Published September 2010 by LG Technical Support and Training

LG Electronics Alabama, Inc.

201 James Record Road, Huntsville, AL, 35813.

New: 2010 Models Software
Downloads Technical Assistance

Presentations with Audio/Video
and Screen Marks

http://136.166.4.200

New Training Materials on

New Training Materials on

the Learning Academy site

the Learning Academy site

6

October 2010 LCD TV 42LE5500

LCD Direct View Overview

LCD Direct View Overview

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.

Checking Points to be Considered

1. Check the appearance of the Replacement Panel and Circuit Boards for both physical
damage and part number accuracy.

2. Check the model label. Verify model names and board model matches.

3. Check details of defective condition and history. Example: Oscillator failure dead set, etc…

7

October 2010 LCD TV 42LE5500

Basic Troubleshooting Steps

Basic Troubleshooting Steps

Define, Localize, Isolate and Correct

•Define
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
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
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.

Look at the symptom carefully and determine what circuits could be causing

After carefully checking the symptom and determining the circuits to be

To further isolate the failure, check for the proper waveforms with the

•Correct
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.

The final step is to correct the problem. Be careful of ESD and make sure to

8

October 2010 LCD TV 42LE5500

42LE5500 PRODUCT INFORMATION SECTION

42LE5500 PRODUCT INFORMATION SECTION

This section of the manual will discuss the specifications of the

42LE5500

LCD Direct View Display

9

October 2010 LCD TV 42LE5500

Wireless Media Box

Wireless Media Box

Wireless Media Box (Sold Separately)

The Wireless Media box communicates to the television via a wireless receiver

called a “Dongle”. The Dongle attaches to the Television via two connections:

1. HDMI Cable from the Dongle to the TV to transfer Audio and Video Signals.

2. Wired Remote cable between the TV and Dongle for Control Functions.

Media Box

Wired Remote to control the Media Box

Wireless Receiver/Transmitter

“Dongle”

Attaches via Velcro to

the back of the set

HDMI

10

TV A/V Inputs

October 2010 LCD TV 42LE5500

Wireless LAN (DLNA Adaptor)

Wireless LAN (DLNA Adaptor)

Wireless LAN (Sold Separately)

Using the LG Wireless LAN for Broadband/1DLNA Adaptor, which is sold separately, allows the TV
to connect to a wireless LAN network. The DLNA adaptor attaches to the Television via either of
the two USB connections:

1(DLNA: Digital Living Network Alliance)

Side A/V Inputs

DLNA Adaptor

“Dongle”

11

Wireless Router

October 2010 LCD TV 42LE5500

Basic Specifications

Basic Specifications

Key TV Features

• LED Plus w/Local Dimming

• NetCast™ Entertainment Access*
(Wi-Fi® Ready)

• Wireless 1080p Ready*

• DLNA Certified®

• TruMotion 120Hz

• Full HD 1080p Resolution

• 5M:1 Dynamic Contrast Ratio

• Picture Wizard II
(Easy Picture Calibration)

• Smart Energy Saving

• ENERGY STAR® Qualified

• Intelligent Sensor

• AV Mode II
(Cinema, Sports, Game)

• Clear Voice II

• ISFccc® Ready

• 24P Real Cinema

• USB 2.0 (JPEG, MP3, DivX HD)

• DivX® HD

• 4 HDMI™ V.1.3 w/Deep Color

• SIMPLINK™ Connectivity

• Dolby® Digital 5.1 Decoder

• Infinite Sound

12

October 2010 LCD TV 42LE5500

Logo Familiarization Page 1 of 4

Logo Familiarization Page 1 of 4

LED Plus

Prepare to be dazzled. Tired of dark scenes or dull colors?
LG’s LED Plus technology provides
even greater control of brightness through local
dimming to deliver amazing clarity and color
detail, as well as a more energy efficient TV
compared to conventional TVs.

TruMotion 120Hz

See sports, video games and high-speed action with virtually no motion blur and
in crystal clarity with LG’s TruMotion 120Hz technology. Now your TV can keep
up with the fastest moving scenes.

NetCast

Entertainment on tap. NetCast Entertainment Access
brings the best Internet services direct to your TV—no
computer required. Instantly access movies and TV
shows, news and weather and the world’s largest library of
HD movies in 1080p.

13

October 2010 LCD TV 42LE5500

Logo Familiarization Page 2 of 4

Logo Familiarization Page 2 of 4

FULL HD RESOLUTION 1080P HD Resolution Pixels: 1920 (H) × 1080 (V)
Enjoy twice the picture quality of standard HDTV with almost double the pixel
resolution. See sharper details like never before. Just imagine a Blu-ray disc
or video game seen on your new LG Full HD 1080p TV.

HDMI (1.3 Deep Color) Digital multi-connectivity

HDMI (1.3 Deep color) provides a wider bandwidth (340MHz,

10.2Gbps) than that of HDMI 1.2, delivering a broader range of
colors, and also drastically improves the data-transmission
speed.

Invisible Speaker
Personally tuned by Mr. Mark Levinson for LG

TAKE IT TO THE EDGE newly introduces ‘Invisible Speaker’
system, guaranteeing first class audio quality personally tuned by
Mr. Mark Levinson, world renowned as an audio authority. It
provides Full Sweet Spot and realistic sound equal to that of
theaters with its Invisible Speaker.

AV Mode "One click" Cinema,

TAKE IT TO THE EDGE is a true multimedia TV with an AV Mode
which allows you to choose from 4 different modes of Cinema, Sports
and Game by a single click of a remote control.

THX

Cinema, Sport, Game mode.

14

October 2010 LCD TV 42LE5500

Logo Familiarization Page 3 of 4

Logo Familiarization Page 3 of 4

Clear Voice Clearer dialogue sound

Automatically enhances and amplifies the sound of the human voice
frequency range to provide high-quality dialogue when background
noise swells.

Save Energy, Save Money

It reduces the plasma display’s power consumption.
The default factory setting complies with the Energy Star requirements
and is adjusted to the comfortable level to be viewed at home.
(Turns on Intelligent Sensor).

Save Energy, Save Money

Home electronic products use energy when they're off to power features like
clock displays and remote controls. Those that have earned the ENERGY
STAR use as much as 60% less energy to perform these functions, while
providing the same performance at the same price as less-efficient models.
Less energy means you pay less on your energy bill. Draws less than 1 Watt in
stand by.

15

October 2010 LCD TV 42LE5500

Logo Familiarization Page 4 of 4

Logo Familiarization Page 4 of 4

Wireless Ready

Wireless 1080p Connectivity lets you cut loose from messy wires and
still get a stunning Full HD picture. Disclaimer: Wireless media kit
required and sold separately.

Picture Wizard

Get easy self-calibration with on-screen reference points for key picture
quality elements such as black level, color, tint, sharpness and
backlight levels. Take the guesswork out of picture adjustments with
this simple-to-use feature. It's not actually magic, but it will sure seem
that way.

5M:1 Dynamic Contrast Ratio

Worrying about dark scenes is a thing of the past. The mega contrast
ratio of 5,000,000:1 delivers vivid colors and deep blacks.

Intelligent Sensor

The Intelligent sensor will monitor the room lighting environment. When
the room lights go out, the TV will automatically adjust the picture for
the best view enjoyment.

16

October 2010 LCD TV 42LE5500

42LE5500 Remote Control

42LE5500 Remote Control

p/n AKB72914003

TOP PORTION

BOTTOM PORTION

17

October 2010 LCD TV 42LE5500

Accessing the Service Menu

Accessing the Service Menu

To access the Service Menu.

1) You must have either Service Remote.
p/n 105-201M or p/n MKJ39170828

2) Press “In-Start”

3) A Password screen appears.

4) Enter the Password.

Note: A Password is required to enter the

Service Menu. Enter; 0000

105-201M

Note: If 0000 does not work use 0413.

18

October 2010 LCD TV 42LE5500

MKJ39170828

TV Rear Input / Output Jacks

TV Rear Input / Output Jacks

LAN

Rear In/Out Jacks

USB1 or USB2 for Software

Upgrades, Wireless Dungle,

Music and Photos

Component or

Composite

Video/Audio 3

Side In/Out

USB 2

USB 1

Wireless Media Box

Remote Jack

MAIN BOARD

Rear and Side

Input/Output locations

19

Head

Phones

HDMI 4

October 2010 LCD TV 42LE5500

Software Updates (New and Changed Functions)

Software Updates (New and Changed Functions)

A wireless Internet Connection will work for Automatic Software Downloads., however if there are
problems completing download, a Wired Internet Connection is preferred

For network setup assistance, press the
green button for the Simple Manual

Bring up the Customer’s
Menu then Press the Red
button on Remote

With Software Update
Highlighted, Press Select
on Remote

Continue on next page

20

Scroll down to item 9 Network Connections

October 2010 LCD TV 42LE5500

Software Updates (New and Changed Functions) Continued

Software Updates (New and Changed Functions) Continued

Automatic Internet Software Update

- Off : Automatic Software update does not work

- On : if new Software released, Software

Check Update version

- comparison current software version and
Released software version

Additional TV Checks can be made by
Scrolling down.
Picture, Sound and Network Test

After completion of the test, a Pop up menu is
displayed with preloaded back ground picture.
Select NO if everything is OK.

download notice appears at turn on with two
choices, Yes and Remind Me Later.

If you select Yes;
Service call number, Model name,
SW version and serial No. is displayed.
Note: Confirm the “Suffix” of the model
number.

If the Main board is replaced, the Model
and Serial number must be reinserted
into memory. See Model Number D/L.

21

October 2010 LCD TV 42LE5500

USB Automatic Software Download Instructions

USB Automatic Software Download Instructions

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.

Currently

Installed

Version

Software

Version

found on the

USB Flash

Drive

File found
on the USB
Flash Drive

* CAUTION:
Do not remove AC power or the USB Flash Drive.
Do not turn off Power, during the upgrade
process.

Software Files are now available from
LGTechassist.com

22

October 2010 LCD TV 42LE5500

Manual Software Download:

Manual Software Download:

Prepare the Jump Drive as described in the “USB Automatic Download” section and insert it into either of the USB ports.
Bring up the Customer’s Menu and scroll to “OPTIONS”.
Press the “FAV” key 7 times to bring up the Manual Download Screen.

Highlight the Software update file
and press “SELECT” to begin the
download process.

Example of files found
On the Jump Drive

WARNING:
Use extreme Caution
when using the
Manual “Forced”
Download Menu. Any
file can be
downloaded when
selected and may
cause the Main board
to become inoperative
if the incorrect file
was selected.

23

October 2010 LCD TV 42LE5500

Service Menu: Downloading EDID Data Pg 1 of 2

Service Menu: Downloading EDID Data Pg 1 of 2

1) Press “ADJ” key. 2) Select menu,
Either “PCM EDID D/L” or AC3 EDID D/L

24

October 2010 LCD TV 42LE5500

Service Menu: Downloading EDID Data Pg 2 of 2

Service Menu: Downloading EDID Data Pg 2 of 2

3) Highlight “Start”

then Press “Select” key.

When PCM EDID D/L was selected

When AC3 EDID D/L was selected

4) When Writing appears
Downloading in progress

5) Downloading Complete

Note: When PCM is downloaded, AC3 will be N/G and when AC3 is downloaded PCM will be N/G.
This means that when PCM is OK, PCM audio is priority and when AC3 is OK, AC3 audio is
priority.

25

October 2010 LCD TV 42LE5500

42LE5500 Product Dimensions

42LE5500 Product Dimensions

Wattage
Local Dimming TBD
Full White TBD
Stand By 0.1W

24.13/16"

629.92mm

27.3/16"

690.88mm

There must be at least 4 inches of Clearance on all sides

40"

1016mm

17.5/16"
440mm

Model No.

Serial No.

12.3/8"

314.96mm

7.7/8"

200mm

Label

Center

11.5/16"
288mm

5.9/16"

142mm

7.7/8"

200mm

Remove 4 screws to

remove stand for

1.3/16"

30.48mm

wall mount

2.3/8" (60.96mm)

Weight w/o Stand 36.8 lbs

Weight with Stand 43 lbs

20.7/16"
510mm

26

10.5/8"

269.24mm

October 2010 42LE5500 LCD-DV

DISASSEMBLY SECTION

DISASSEMBLY SECTION

This section of the manual will discuss Disassembly, Layout

(Circuit Board Identification) of the 42LE5500 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

Disassembly:

circuit boards and be able to identify each board.

27

October 2010 LCD TV 42LE5500

Removing the Back Cover

Removing the Back Cover

Pay attention to the size and type of screw

The AC Cord

Does Not unplug

Remove plastic

cover.

Remove the 28 screws indicated.

as there are many different types.

Putting in an improper screw when

reassembling may Cause damage.

The Stand has to be removed before removing the back.

28

October 2010 LCD TV 42LE5500

The Stand Bracket has a

plastic cover “Not Shown”

that must be removed to

expose the screws.

Circuit Board Layout

Circuit Board Layout

Clips hold the front glass in place, use caution. Add screws while servicing.

Power Supply

(SMPS)

To LEDs

LVDS Cables

Panel Connection

Points

Warning: The Frame has

very sharp edges

Main Board

IR/LED

Board

Soft Touch

Keyboard

Invisible

Speaker Right

LG Logo

Board

29

Invisible

Speaker Left

October 2010 LCD TV 42LE5500

42LE5500 Connector Identification Diagram

42LE5500 Connector Identification Diagram

TFT PANEL

p/n: EAJ60871201

To LEDs

If the Panel is replaced, reset the UTTTime.

Service Menu, System 1 Item 12

J3

POWER

SUPPLY

p/n: EAY60803101
p/n: EAY60803201

J2

J1

AC In

P204

P205

P201

SK101

White Plug

Black Plug

To

TFT

Panel

P7501 P7500

n/c

n/c

p/n: EBU60904603
p/n: EBR66101301
p/n: EBU60904602

P8800

P8200

P8000

MAIN

BOARD

IR LED

p/n: EBR64966201

Soft Touch Keys

p/n: EBR64966801

Speaker (Front Right)

p/n: EAB60961501 p/n: EAB60961501

p/n: EAV60793302

30

Speaker (Front Left)

October 2010 42LE5500 LCD-DV

Power Supply

Power Supply

Board Removal

Board Removal

Board is “Thin”, be

careful not to flex.

Disconnect

P201, P204,

P205 and AC

In SK101.

p/n EAY60803101

P

2

4

0

P

2

5

0

P

2

0

1

P201

Press in

gently on

the two

tabs

to release

lock

SK101 fits very

snug into it’s

connector.

Remove the 6

screws indicated

by the arrows.

31

AC In

SK101

Press in on the

two tabs

to release lock

October 2010 LCD TV 42LE5500

Removing the Main Board

Removing the Main Board

p/n EBU60904603

Flip the locking tab upward, pull the LVDS ribbon out.

Disconnect P7500,

P7501, P8000, P8200 and

P8800

Remove any tape holding

down any cables.

Remove the 7 screws

indicated by the arrows.

Remove decorative

plastic and remove the

board.

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.

N/C

N/C

P7501 P7500

P8000

Press in on the

side release

tabs to remove.

Decorative

Metal Plate

After removing the Main, there

are tabs sticking through the

Main board holding the Metal

plate in place.

P8800 P8200

32

October 2010 LCD TV 42LE5500

Removing Front IR Board

Removing Front IR Board

Tab

J3

Disconnect J1, J2 and J3 connectors.

Press upward on the two tabs at the top. Tilt the board downward.

Lift straight up To Clear the Tabs at the bottom.

Tab

J2

IR board / Intelligent Sensor

J1

Tab Tab

33

October 2010 LCD TV 42LE5500

p/n EBR64966201

TROUBLESHOOTING SECTION

TROUBLESHOOTING SECTION

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

Troubleshooting:

problems.

34

October 2010 LCD TV 42LE5500

POWER SUPPLY SECTION

POWER SUPPLY SECTION

This switch mode power supply develops Stand By 3.5V
at all times when AC is applied.
At power on, it develops 12V and 20V for the Main board.
It develops 120V for the LED Backlights.

This power supply draws less than 1 watt during stand by
mode. The fuse F101 and F103 reads 7.6V
(from hot ground) during this time.

When the controller chip receives the PWR-ON command

3.36V via P201 Pin 1, the primary section increases its
current supplying ability. Both Primary fuses F101 and
F103 now read a little more than 395V.
T102 delivers AC to D206 which develops the 120V for
the LED backlights.

P201 Connector: (To Main Board)

12V (11.43V) is routed out P201 pins 17, 19 and 21 and
20V (21.27V) is routed out P201 pins 2, 3 and 4.

P204 Connector: (To Panel LEDs)

120V is routed out P204 pins 1 and 12.

P205 Connector: (To Panel LEDs)

120V is routed out P205 pins 1 and 12.

35

October 2010 LCD TV 42LE5500

Power Supply (SMPS) Board Layout

Power Supply (SMPS) Board Layout

p/n EAY60803101

F101

3.15A/250V
F103

1A/250V

STBY 7.6V

Run 396V

From Hot Gnd

F100

5A/250V

F102

1A/250V

AC Protect

36

Hot Ground

Shock

Hazard

October 2010 LCD TV 42LE5500

42LE5500 Power Supply Start Up Sequence

42LE5500 Power Supply Start Up Sequence

AC In

No AC

Det in

this

T510 &

Rectifier

model

P201

At point TV is in
Stand-By state.
Energy Star compliant.
0 .1 Watts

3

P8000

3.5V_ST

2

Other Regs

Reset

Generator

C8108
R8184

Primary side fuses:

Stand-By 7.6V Run 396V (Hot Gnd)

1

BridgeRelays

Stand By

3.5V Reg

5

Stand By

3.5V

RL_ON

2 5 66 8

19~12 16

MAIN

BOARD

Note 1:

5

RL_On

5

5

Power On

Power

2

3

RL_ON

On

Model 1_Opt1 Panel Control

Microprocessor IC8101

5

12V

See

T102
D206

Inverter On

Starts the Inverters

12V/24V

Regulators

24V

17
19
21

IC8801

Audio Amp

12V

8

INV_CTL

Key 1 or IR

POWER SUPPLY (SMPS)POWER SUPPLY (SMPS)

On Board

Inverter

8

9

9

9

Local Dimming (SIN)

V-SYNC

Inv
On

Inverter On

7

4

P-DIM

Globar

9

Dimming

22182~4

IC9302

1.8V_L/

Dimming

P-DIM

Q8004

Panel

VCC

12V

7

9

Processor

7.8V

Video

IC900

IC9102

HVDD

7

IC9301

Dimming

IC9103

DC to

DC

16V, -5V,

9

23

IC

3.3V,
26V,

P8200

P204

8

P205

8

SIN

MOSI, CLK

12 Blocks

7

120V

6

To Panel Backlights

Local and

Global Dimming

Manipulates Backlight

120V

6

Local and

Global Dimming

P-DIM1 (PWM-DIM)

Pulse Width Dimming

Global Dimming

Manipulated by:

Cust Menu for Backlight

Note 1:
12V TURNS ON:
IC8000 5V_USB
IC8003 5V_Normal
IC8005 3.3V_Normal
IC8903 +3.3V_MEMC

IC8902 +1.26V_MEMC
MEMC=
Motion Estimated Motion Compensated
For Video Processor

VCC 3.3V, VDD 16V,

VGL -5V, VGH 26V,

HVDD 7.8V

P7500

P7501

4

Ft IRKey

and

Picture Content

Manipulate P-DIM

7

After Mute Released

LVDS Video

9

And Tru-Motion LVDS Video

LCD PANEL

120Hz

LEDs

Low = Bright

Right Side

Panel

Driver Board

Left Side

Panel

Driver Board

Soft Touch Key

37

Remote or Power Button Key

October 2010 42LE5500 LCD-DV

42LE5500 Television Turn On Commands Circuit Drawing

42LE5500 Television Turn On Commands Circuit Drawing

To IC9103 DC to DC

Conv T-CON

SBY3.5V

VSYNC

12V

INV_CTL

12V

12V

PWM-DIM

ERR OUT

PWR

24V

SCLK

SIN

SMPS

P201

1
2

3
4
5
6
7
8

9
10
11
12

13 13
14

15
16 16
17

18
19

20 20
21

22
23 23
24

3.36V

0.02V

11.43V

3.28V

11.43V

0.09V

11.43V

0.38V~3.3V

21.27V

21.27V

21.27V
Gnd
Gnd
Gnd
Gnd

3.5V

3.5V

3.5V

3.5V
Gnd
Gnd

Gnd

3.3V
Gnd

MAIN Board

P8000

1
2

3
4
5
6
7
8

9
10
11
12

14
15

17
18
19

21
22

24

PWM-DIM (PWM Dimming) can vary according to

incoming video IRE level, OSD Backlight setting
and Intelligent Sensor (room light condition).
Range 0.37V to 3.3V.

(Data) 3.25V p/p Data

Panel_Vcc (12V)

+3.3V_Normal

PWR-ON

L8005

PWM-DIM

3.64V
p/p

3.76V p/p

C8024

68uF

+3.5V_ST

L8015

3.36V

+24V

24.6V

L8003

C8001 100uF

L8002

INV_On

VSYNC

SCLK

SIN

Q8004

D

7

IC8005

8

Power_On/Off2_2

Q8002

3.3V

3.36V

C8000

100uF

+12V

11.9V

R8019

100

R8078

R8077 0

0V

R8004

4.7K

3.1V

0

R8076 0

38

S

R8010 10K

11.8V11.79V

G

2

3.36V

6

Q8000

0V

1.8V

11.8V

L8013

R8060

10K

0.66V

R8000

10K

+3.5V_ST

R8184

47K

R8026

1K

Q8005

0V

P-DIM: Digital

Dimming (Variable)

VSYNC / R_VS

M2_SCLK

M2_MOSI

October 2010 42LE5500 LCD-DV

R8011 1.8K

+12V

RL_ON

Reset

C8108

0.1uF

+3.3V_Normal

R8032

10K

R1041 0R8027 0

R9346

22

R9347 22

R8003 22K

Q8003

0.68V

R8176

22K

R8187

22

R8178

22

R8134

22

R9350

22

L8000

Q8001

Power

20

On/Off 2_2

IC8101

Micro

36

RL_ON

Model_Opt_1

Reset

40

Power Det

10

INV_CTL

R25

GPIO 09

IC900

BCM

U5

IC9301

Dimming

R6
T6

0V

IR

Key 1
Key 2

+12V

R8001

47K

R8103

100

16

11

R8135

22

14

25
26

R_VS
M2_SCLK
M2_MOSI

Power Supply Board Low Voltage Test 1

Power Supply Board Low Voltage Test 1

AC Should not be applied at any time while adding jumpers or
While unplugging connectors as damage to the circuit Board
may occur.

a) When AC is applied, the SMPS “MUST” be producing

STBY 3.5V on pins 9, 10, 11 or 12 of P201.

If 3.5V Standby is not being generated, the SMPS is defective
and must be replaced. There is no need to continue with the
next test.
But, make sure AC is arriving at the connector SK101.

(b) Unplug P8000 on the Main Board to make insertion of the Jumpers easier.

Use P700 Side to insert resistors

Pin 1 is the

Brown Wire

TEST 1:

(1) Add a jumper between (3.5V STBY) pin 7, 8, 9 or 10 and Pin 1 (PWR_ON). Apply AC.

This will turn on the power supply, relays will click.
a) Check that the 24V and 12V power supplies are turned on,

• P201 (12V pins 17, 19 and 21)

• P201 (24V pins 2, 3 and 4)

• P204 and P205 (120V pins 1 and 12) to the Panel. (Or check D206 + lead)

(2) Remove AC power

No Backlights during this test

39

October 2010 LCD TV 42LE5500

Power Supply Board Backlights Test 2

Power Supply Board Backlights Test 2

Continue if the 1sttest was OK.
Leave original jumper in place.

(3) Add another jumper between (STBY_3.5V)

pin 9, 10, 11 or 12 and Pin 18 (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.
c) Check the connections to the Panel.

If the Inverter On command is pulling up to 3V and the 120V is being generated
from D206 + lead, See the Inverter Section of the Power Supply for additional checks.
Note: If either P204 or P205 is disconnected, the backlights will come on,

but shut off in 4 seconds.

REMOVE AC POWER:

40

October 2010 LCD TV 42LE5500

Pin 1 is the

Brown Wire

42LE5500 Inverter Part of the SMPS

42LE5500 Inverter Part of the SMPS

Gnd

1V (100 IRE)

30V (0 IRE)

Inverter Top Left Connector

1VDD-33 3.5V
2 VLED-RANGE 0V
3Gnd Gnd
4 +12VS 12.44VPin 17-19-21 P201
5Gnd Gnd
6 +3.5VS 3.57VPin 9-12 P201

Inverter Center Left Connector

1 INV_ON 3.28VPin 18 P201
2Gnd Gnd
3Gnd Gnd
4 SCLK 0.09VPin 20 P201
5 FB_STR_VF 1V
6 P-DM1 1.9VPin 22 P201

Inverter Bottom Left Connector

1Error 0VPin 24 P201
2(L-DIM) SIN 3.3VPin 23 P201
3 POWER_ON 3.35VPin 1 P201
4 VSYNC_IN 0VPin 16 P201
5Gnd Gnd
6Gnd Gnd

Pin 23 P201

3.25V p/p

Local Dimming On

100uSec

L-DIM (SIN)

Pin 23 P201

3.25V p/p

Local Dimming Off

100uSec

L-DIM (SIN)

Gnd

INVERTER

Section of the

SMPS

Pin 16 P201

3.64V p/p

V-Sync Signal

Pin 20 P201

B

E

C

B

E

C

B

E

C

B

E

C

B

E

C

B

E

C

B

E

C

B

E

C

B

C

E

B

C

E

B

C

E

B

E

C

P204

120V

n/c

*1V~30V LED Drive

n/c

*1V~30V LED Drive

n/c

120V

P205

120V

n/c

*1V~30V LED Drive

n/c

*1V~30V LED Drive

n/c

120V

*White 100 IRE to Black 0 IRE

These drivers ground the LED blocks. (12 Total). If the

120V is present on Pins 1 and 12 of P204 and P205

you can ground these test points to turn on a block.

LED Drive Signal 50 IRE

3.76V p/p

41

SCLK Signal

32V p/p

10mSec

October 2010 42LE5500 LCD-DV

Power Supply Connector P201 Voltage and Diode Check

Power Supply Connector P201 Voltage and Diode Check

P201 Connector “SMPS” to “Main” P8000

Run STBYLabelPin

0.178V11.43V0V12V21

0.178V11.43V0V12V19

0.178V11.43V0V12V17

Diode

Check
*1.45VGndGndERROR24

Open3.3V0VL-DIM (SIN)23
Open0.38V~3.3V0VP-DIM122

Open0.09V0VSCLK20

Open3.28V0VINV-ON18

Open0.02V0VV_SYNC16

GndGndGndGnd13-15

Open3.5V3.57V3.5V9-12

P201 Label

P201 Connector

Odd pins

are on

front row

1

GndGndGndGnd5-8

1.10V21.27V0V24V2-4

1.02V3.36V0VPWR-ON1

*Pin 24 is grounded on the Main Board

Diode Mode values taken with all Connectors Removed

(1) PDIM1 Pin 22 can vary according to incoming video IRE
level, OSD Backlight setting and then Intelligent Sensor
(room light condition) Output from the Video Processor
IC900. Range 0.37V to 3.3V.
.

P-DIM1

3.66V p/p 50IRE

42

October 2010 LCD TV 42LE5500

Power Supply Connector P204 / P205 Voltage and Diode Check

Power Supply Connector P204 / P205 Voltage and Diode Check

P204 "SMPS" to “The Panel"

Run STBYLabelPin

(1)

1V~30V0V02-1C10

(1)

1V~30V0V02-2C9

(1)

1V~30V0V02-3C8

(1)

1V~30V0V01-3C5

(1)

1V~30V0V01-2C4

(1)

1V~30V0V02-1C3

Diode

Check

Open120V0V02.A12
Openn/cn/cn/c11
Open
Open
Open
Openn/cn/cn/c7-6
Open
Open
Open
Open0Vn/cn/c2
Open120V0V01.A1

P205 "SMPS" to “The Panel"

Run STBYLabelPin

(1)

1V~30V0V04-1C10

(1)

1V~30V0V04-2C9

(1)

1V~30V0V04-3C8

(1)

1V~30V0V03-3C5

(1)

1V~30V0V03-2C4

(1)

1V~30V0V03-1C3

Diode

Check

Open120V0V04.A12
Openn/cn/cn/c11
Open
Open
Open
Openn/cn/cn/c7-6
Open
Open
Open
Open0Vn/cn/c2
Open120V0V03.A1

P204

1

P205

1

(1)

The drive signal changes due to the brightness level of the

backlights. Low indicates “Bright”. High indicates “Dim”.

Diode Mode values taken with all Connectors Removed

43

October 2010 LCD TV 42LE5500

Power Supply Connector SK101 and AC Fuses Voltage and Diode Chec

Power Supply Connector SK101 and AC Fuses Voltage and Diode Chec

k

k

F102

1A/250V

AC

F102

F100

6.3A/250V
AC IN

F100

AC Voltage Readings (From Hot Ground)
Pins 1 and 2 for STBY and RUN.

Diode Mode values taken with all Connectors Removed

LN

SK101 "SMPS" to AC IN

LEL1

120Vac

F100 or F102 (Diode Check)

Main Power Switch Closed

Red or Black Lead on Fuse (Open)

Other Lead on Hot Ground

Diode CheckRun STBYLabelPin

OL
OLNEL3

Bottom Right of SMPS

SK101

44

October 2010 LCD TV 42LE5500

Power Supply F101 and F103 Voltage Checks

Power Supply F101 and F103 Voltage Checks

F100

3.15A/250V

F103

1A/250V

From Hot Gnd

From Hot Gnd

STBY 7.6V

STBY 7.6V

Run 396V

Run 396V

If the set was on and then turned off into the Stand-By condition, the voltage

takes a very long time to bleed down to the reading given here.

45

October 2010 LCD TV 42LE5500

MAIN BOARD SECTION

MAIN BOARD SECTION

The Main board receives its operational B+ from the Power Supply via P8000.
There are two LVDS cable feeds that are output from the on-board T-CON (TFT Driver) section
directly to the Panel. These carry the duel 12 bit LVDS Video and TruMotion Video equaling a 120Hz
video signal. These signals have already been prepared for the Panel’s Left and Right boards. The
Main board also includes the Tuner, Audio and Audio/Video inputs and selection circuits.

Input Voltages from SMPS.

STAND-BY

RUN

• STBY 3.5V (P8000 pins 9~12)

The Main board also develops several B+ sources on the board.

STAND-BY VOLTAGES

• 3.3V_ST (Voltage direct from SMPS).

LVDS

GENERAL

• 5V_Normal (Made from 12V In).

• 3.3V_Normal (Made from 12V In).

• 5V USB (Made from 12V In).

• Panel_VCC (12V Not generated, but switched
from the 12V arriving from the SMPS).

TUNER and VSB CIRCUIT

• 3.3V_TU (Made from 3.3V_Normal).

• 1.26V_TU (Made from 3.3V_TU).

BCM IC900 Micro/Video Processor

• 3.3V_ST, 1.2V, D1.5V, D1.8V

IC9301 Tru-Motion and Dimming IC

• 1.26V_MEMC, 1.5V_MEMC,

and 3.3V_MEMC

WIRELESS VOLTAGES to JK8700

• 20V (Switched from 20V from SMPS)

AUDIO IC8801

• 1.8V (Made from 3.3V_Normal).

T-CON IC9001

• 3.3V_VCC, -5V_VGL, 27V_VGH,
16V_VDD and HVDD (7.8V)

HDMI VOLTAGES (Q200)

• 1.8V_HDMI (From D1.8V)

• 12V pins 13 and 14

• 20V pins 17 and 18.

46

October 2010 LCD TV 42LE5500

Main Board Layout

Main Board Layout

To Panel

P7501

P8000

To SMPS

P7500

See next page for

component

identification

P9000

n/c

P8100

n/c

LAN

IC9301

IC901

IC900

p/n:

EBU60904603

VIDEO
PROCESSOR
IC900, T-CON

IC9001 and

Tru-Motion IC9301

runs Hot.

This is normal.

USB 1

USB 2

Component In

These connectors are

Mini plug type

Headphone

Wireless Remote

P8800

To Speakers

P8200 To Front IR

47

HDMI

October 2010 LCD TV 42LE5500

42LE5500 Main Layout

42LE5500 Main Layout

QD

ECB

A1CA2

Tru-Motion

Microprocessor

Videoprocessor

SW9300

Reset

SW8100

Reset

SW1000

Reset

X9300
25Mhz

IC9300

SW9300

X9000
12Mhz

X8100

IC8801

Q8700

P9000

Update

IC8101

Q8800

L8805L8804

P8800

P7501 P7500

IC9301

LG5111

RX/TX

IC9001
T-CON

LG7378A

IC1000

SW8100

SW1000

Micro

IC8804

IC8800

IC8300

Q?

Q8200

Q8201

P8200

IC9100

A

D9101

C

D9102

L9301

IC8900

IC8901

IC900

Video Processor

LGE3549XQ

MAIN BOARD

p/n: EBU60904603

HDMI
Select

L9100

IC9103

A-C

A

A-C

C

IC9302

IC605IC603

L8904

IC9102

L9102

L9101

IC8902

L8012

Q8004

G

Q8003

P9000

Gamma

IC300

Q300

Q8005

D

Q8001

S

Q8008

L8905

IC8202

L8009

IC8000

IC901

54MHz

IC700

TDVJ-H031F

Digital Video

Analog Video

Audio

Tuner Data

Tuner Clock

Tuner B+

P8000

1

2

2

3

Q8007

IC8903

IC8001

L8004

X1001

TU700

18. IF p

17. IF n

16. IF AGC

15. Reset

14. 3.3V

13. 1.26V

12. GND

11. CVBS

10. NC

9. SIF

8. NC

7. SDA

6. SCL

5. NC

4. NC

3. 5V

2. NC

1. NC

IC8005

1

3

L8015

IC8003

L8010

IC301

IC302

USB1

USB2

Component

Composite

HP

HDMI

A1

A2

C

D8310

48

October 2010 42LE5500 LCD-DV

42LE5500 Main (Front Side) Component Voltages

IC300 Earphone Amp IC700 (+1.26V_TU) IC8002 (D1.8V) IC8005 (+3.3V_NORMAL) IC8902 (+1.26V_MEMC) IC9102 DC to DC

Pin Pin Regulator Pin Regulator Pin Regulator Pin Regulator Pin HVDD T-CON

[1] 0V [1] 0V (Gnd) [1] 5V [1] 0V (Gnd) [1] 0V (Gnd) [1] 0V (Gnd)
[2] 0V [2] 1.26V (Out) [2] 3.34V (In) [2] 11.8V (In) [2] 11.8V (In) [2] 11.72V (In)
[3] 0V [3] 3.3V (In) [3] 1.8V (Out) [3] 0V (Gnd) [3] 0V (Gnd) [3] 11.72V (In)
[4] 0V [4] Gnd [4] 0.8V [4] 0.8V [4] 3.25V
[5] 0V IC1000 SOC Reset [5] Gnd [5] 0.86V [5] 0.7V [5] 3.2V
[6] 3.3V Pin Generator [6] 0.9V [6] 3.36V (PWR On/Off2 Ctl) [6] 3.36V (PWR On/Off2 Ctl) [6] 0V
[7] 3.3V [1] 3.32V (In) [7] 0.9V [7] 3.36V (Out) [7] 1.3V (Out) [7] 0V

[8] (-1.8V) [2] 0V (Gnd) [8] 1V [8] 3.36V (Out) [8] 1.3V (Out) [8] 11.7V

[9] (-0.8V) [3] 3.3V (Out) [9] 2.38V [9] 0V (Gnd)
[10] Gnd [10] 3.36V (PWR On/Off1 Ctl) IC8007 Power Det Gen IC8903 (+3.3V_MEMC) [10] 1.13V
[11] 0.9V IC8000 5V Regulator Pin (+12V and +3.5V) Pin Regulator [11] 0V (Gnd)
[12] 1.8V Pin for USB IC8003 (+5V_NORMAL) [1] 0V (Gnd) [1] 0V (Gnd) [12] 0V (Gnd)
[13] 3.3V [1] 11.79V (In) Pin Regulator [2] 3.6V (In) [2] 11.8V (In) [13] 0V (Gnd)
[14] 3.3V [2] 5V (Out) [1] 0V (Gnd) [3] 3.5V (Out) [3] 0V (Gnd) [14] 7.7V
[15] Gnd [3] 5V (Out) [2] 11.8V (In) [4] 0.8V [15] 7.7V (HVDD)
[16] 0V [4] 10.5V [3] 0V (Gnd) IC8008 Power Det Gen [5] 0.8V [16] 0V (Gnd)

IC301 Switched [6] 0.8V [5] 0.86V [1] 0V (Gnd) [7] 3.3V (Out) IC9300 Reset for

Pin 5V for USB 2 [7] 4.99V [6] 3.37V (PWR On/Off2 Ctl) [2] 3.6V (In) [8] 3.3V (Out) Pin LG5111

[1] Gnd [8] 0V (Gnd) [7] 5V (In) [3] 3.7V (Out) [1] 3.32V (In)

[2] 5V (In) [8] 5V (In) IC9100 P-GAMMA [2] 0V (Gnd)

[3] 5V IC8001 D1.2V and A1.2V IC8800 (+1.8V_AMP) Pin Chip [3] 3.34V (Out)

[4] 3.3V Pin Regulator IC8004 A2.5V Regulator Pin Regulator [1] 3.3V

[5] 3.3V [1] 0V (Gnd) Pin for USB [1] 0V (Gnd) [2] 0V (Gnd) IC9302 (1.8V_L/Dimming)

[6] 5V (Out) [2] 3.3V [1] n/c [2] 1.8V (Out) [3] 3.3V (In) Pin Regulator

[7] 5V (Out) [3] 0V (Gnd) [2] 3.26V (In) [3] 3.295V (In) [4] 0V (Gnd) [1] 0V (Gnd)

[8] n/c [4] 1.2V [3] 3.26V (In) [5] 6.8V [2] 11.8V (In)

IC302 Switched [6] n/c [5] n/c Pin Regulator [7] 15.3V [4] 0.8V

Pin 5V for USB 1 [7] 4.46V [6] 2.55V (Out) [1] 0V (Gnd) [8] 15.3V [5] 0.76V

[1] Gnd [8] 3.3V [7] 0.8V [2] 1.5V (Out) [9] n/c [6] 3.34V (PWR On/Off2 Ctl)

[2] 5V (In) [9] 3.3V [8] 0V (Gnd) [3] 3.3V (In) [10] 13.47V [7] 1.8V (In)

[3] 5V [10] 3.3V [11] 12.75V [8] 1.8V (In)

[4] 3.3V [11] 1.2V Q8005 INV_ON Q8306 HDMI [12] 11.8V

[5] 3.3V [12] Gnd Pin Driver Pin Det [13] 10V D9101 VGH/VDD

[6] 5V (Out) [13] 3.3V B 0V (INV ON) En B 0V [14] 5.96V Pin Rectifyer

[7] 5V (Out) [14] 0.8V C 3.1V (Out) C 3.3V [15] 4.06V A 15.4V

[8] n/c E Gnd E Gnd [16] 15.3V AC 22.2V

Q300 Earphone Mute Q8003 PANEL_VCC Q8200 IR Buffer Q8307 HDMI [18] 2.96V

Pin L Out Pin

B 0V B 0.679V B 0.02V B 0V [20] 3.3V (In) Pin Rectifyer
C3.3V C0V C3.4V C4.18V A (-5V VGL)
EGnd EGnd EGnd EGnd AC (-1.9V)

Q8001 PANEL_VCC Q8004 PANEL_VCC Q8201 IR Buffer Q8700 Wireless PWR Q8800 AMP_MUTE

Pin

Control 1st Driver Pin Switch Pin 1st Dongle Out Turns on Q8701 Pin Pin 25 IC8801

B 0V S 11.8V (In) B 0V B 0.66V (0.0V Dongle In) B 0V
C 0.68V G 1.8V (Enable) C 3.3V C 0.14V (24V Dongle In) C 3.336V
E Gnd D 11.8V (Out) E Gnd E Gnd E Gnd

[5] 3.3V [4] 0.8V Pin (+24V) [6] 3.36V (PWR On/Off2 Ctl)

[5] 3.3V [4] n/c IC8901 (+1.5V_MEMC) [6] 6.8V [3] 0V (Gnd)

Control 2nd Driver Pin 2nd Pin Det [19] 2.33V D9102 VGL/VCC

[17] 0V C 27.4V (VGH)

C0V

49

October 2010 42LE5500 LCD-DV

42LE5500 Main (Back Side) Layout

42LE5500 Main (Back Side) Layout

QD

ECB

A1CA2

Digital Video

Analog Video

Audio

Tuner Data

Tuner Clock

Tuner B+

Q8002

1

3

2

Q8000

TU700

TDVJ-H031F

18. IF p

17. IF n

16. IF AGC

15. Reset

14. 3.3V

13. 1.26V

12. GND

Q702

11. CVBS

10. NC

9. SIF

8. NC

7. SDA

6. SCL

Q701

5. NC

4. NC

3. 5V

2. NC

1. NC

IC602

Q901

Rubber

MAIN BOARD

p/n: EBU60904603

IC606 IC604

IC8200

Rubber

IC8401

Rubber

IC8400

Q8303

Q8305

IC9001

IC9003

D8309

D8306

Q8304

Q200

D

Q8301

D8307

Q8300

Q8302

S
G

Q8701

Q8205

IC9000

IC8100

D8312

Q8308

IC8700

D
GSB

Rubber

50

Q8203

October 2010 42LE5500 LCD-DV

42LE5500 Main (Back Side) Component Voltages

)

IC602 D1.8V IC8400 RGB IC8700 Wireless Q200 (1.8V_HDMI) Q8203 IR Wireless Pass

Pin Regulator Pin H/V Sync Pin Buffer Pin Switch Pin 2nd Driver

[1] 0V (Gnd) [1] 1.9V [1] 0V (3.3V Dongle In) S 1.83V (Out) B 0V
[2] 3.29V (PWR On/Off1 Ctl) [2] 1.9V [2] 3.3V (0.3V Dongle In) G 3.35V (PWR On/Off2 Ctl) C 3.3V
[3] 0.9V (DDR_VTT) [3] 4.4V [3] n/c D 1.83V (In) E Gnd
[4] 0.93V [4] 0V [4] n/c
[5] 1.83V [5] 0.9V [5] n/c Q701 Tuner SIF
[6] 3.38V (In) [6] n/c (4.5V) [6] Gnd Pin (Sound) Buffer Q8205 IR Wireless Pass
[7] 1.8V (Out) [7] 0V (Gnd) [7] Gnd B 0.16V Pin 1st Driver
[8] 0.91V (DDR_VTT) [8] n/c (4.5V) [8] Gnd C Gnd B 0.6V

[9] n/c (1.9V) [9] n/c E 0.83V C 0V

IC8100 EEPROM [10] n/c (1.9V) [10] 0.02V EGnd

Pin Micro [11] n/c (4.5V) [11] 0V Q702 Tuner Video

[1] 0V (Gnd) [12] 0.9V [12] 3.3V Pin (Analog) Buffer Q8300, 2 HDMI 2
[2] 0V (Gnd) [13] 0.9V [13] 0V (3.3V Dongle In) B 2.05V Pin Det
[3] 0V (Gnd) [14] 5V [14] 3.3V C 2.75V B 4.2V
[4] 0V (Gnd) [15] 3.3V E Gnd C 0V
[5] 3.37V IC8401 EDID Data [16] 3.3V EGnd
[6] 3.37V Pin PC Q901 FLASH_WP
[7] 0V (Gnd) [1] 0V (Gnd) IC9303 EEPROM Pin for IC901 Q8303, 4, 5 HDMI 3
[8] 3.37V [2] 0V (Gnd) Pin for LG5111 B 0V (Flash_WP) Pin Det

[3] 0V (Gnd) [1] 0V (Gnd) C 3.36V B 0V

IC8200 RS232 [4] 0V (Gnd) [2] 0V (Gnd) E Gnd C 4.2V

Pin Routing [5] 0.7V [3] 0V (Gnd) EGnd

[1] 0V [6] 4.1V [4] 0V (Gnd) Q8000 RL_ON (PWR_On)
[2] 0V [7] 4.5V [5] 3.37V Pin 1st Driver Q8308 CEC Remote
[3] 0V [8] 4.5V (In) [6] 3.37V B 0.66V Pin HDMI CEC
[4] 0V [7] 3.34V C 0V [B] 2.72V
[5] 0V IC9000 Serial Flash [8] 3.37V (In) E Gnd [G] 2.73V
[6] (-5.47V) Pin T-CON [S] 3.27V
[7] n/c (5.59V) [1] 0.06V Q8002 PWR_ON [D] 3.37V

[8] n/c (0V) [2] 0.67V D8306, 7, 9 5V Pull Up Routing Pin Switch

[9] n/c (3.3V) [3] 3.3V (In) Pin HDMI SCL/SDA [1] 3.36V (In) Q8701 IR Wireless Pass
[10] n/c (0.2V) [4] 0V (Gnd) A1 5.04V [2] 0V Pin 2nd Driver
[11] n/c (3.3V) [5] 0V C 4.58V [3] 3.3V (Out) G 24.5V (2.3V Dongle I
[12] 3.35V [6] 0.34V A2 0V S24V
[13] 0V [7] 3.31V (In) D 0V (24.5V Dongle In
[14] (-5.47V) [8] 3.34V (In) D8312 3.5V Pull Up
[15] 0V (Gnd) Pin HDMI CEC
[16] 3.37V A1 0V

C3.26V

A2 3.2V

51

October 2010 42LE5500 LCD-DV

Main Board X9001 and X9000 Crystal Checks

Main Board X9001 and X9000 Crystal Checks

IC9301 TruMotion /

Dimming Crystal

3.19V p/p

4.86V p/p

X9001

X9001

25Mhz

1.58V

Runs when

set is On

1.6V

IC9001 T-CON Crystal

3.27V p/p

2.54V p/p

X9000

1.56V

1.6V

12Mhz

Runs when

set is On

X9000

MAIN Board

52

October 2010 LCD TV 42LE5500

Main Board X8100 and X1001 Crystal Checks

Main Board X8100 and X1001 Crystal Checks

IC8100 Micro Crystal

Either leg

Either leg

3.13V p/p

2.26V p/p

X8100

10Mhz

Runs all

The time

1.95V

1.52

IC900 BCM Crystal

Either leg

X1001

781mV p/p

789mV p/p

54Mhz

Runs when set is On

1.52V

1.3V

1.85V p/p 2.82V p/p

Runs all

The time

1.75V1.5V

53

MAIN Board

X8100
X8101

X1001

October 2010 LCD TV 42LE5500

Main Board DC to DC Converter (Voltages for Panel) Checks

Main Board DC to DC Converter (Voltages for Panel) Checks

Location: Top Center of Board

+27V

VGH

D9101

+16V

VDD

+7.81V

HVDD

IC9103

L9100

IC9102

Panel 12V

L9104

B+ for
IC9102
IC9103

L9102

Panel 12V

L9101

-5V

VGL

D9102

54

+3.3V

VCC

October 2010 LCD TV 42LE5500

Main Board Additional Panel Voltage Checks

Main Board Additional Panel Voltage Checks

Location: Top Left of Board

P7500P7501

IC9101

Back Side of Board

From IC9101 Pin 19

-4.7V (VST)

55

From IC9101 Pin 21

-4.8V (VDD-ODD)

From IC9101 Pin 20

-4.8V (VDD-EVEN)

October 2010 LCD TV 42LE5500

Main Board Connector P8000 to Power Supply Voltage and Diode Che

Main Board Connector P8000 to Power Supply Voltage and Diode Che

ck

ck

P8000

Odd Pins Front Row

Diode Mode values taken with
all Connectors Removed

P8000 “Main Board" to P201 “SMPS"

Diode CheckRun STBYLabelPin

Open3.36V0VPWR-ON1
Open21.27V0V24V2-4

GndGndGndGnd5-8

1.24V3.5V3.57V3.5V9-12
GndGndGndGnd13-15

1.06V0.02V0VV-SYNC16

Open11.43V0V12V17

1.62V3.28V0VINV-ON18

Open11.43V0V12V19

1.06V0.09V0VSCLK20

Open11.43V0V12V21
Open0.38V~3.3V0VP-DIM22

(1)

PDIM Pin 22 can vary according to incoming video IRE level,
OSD Backlight setting and Intelligent Sensor (room light condition).
Range 0.37V to 3.3V.

56

1.05V3.3V0VL-DIM (SIN)23
GndGndGndERROR24

P-DIM1

3.66V p/p 50IRE

October 2010 LCD TV 42LE5500

Main Board Connector P7500 to the Panel Voltage and Diode Check

Main Board Connector P7500 to the Panel Voltage and Diode Check

P7500 Connector “Main" to the “Panel“

RunLabelPin

Diode

Check

GndGndGnd1
Open14.91VGMA12
Open13.5VGMA33
Open12.78VGMA44
Open11.88VGMA65
Open10.02VGMA76
Open8.02VGMA97
Open7.48VGMA108
Open5.99VGMA129
Open4.08VGMA1310
Open2.98VGMA1511
Open2.35VGMA1612

There are no Stand-By Voltages for the Connector
Diode Mode values taken with all Connectors Removed

RunLabelPin

Diode

Check

0.9V1.06VLV0+21

1.09V1.27VLV0-22

0.9V1.4VLV1+23

1.09V1.3VLV1-24

0.9V1.03VLV2+25

1.09V1.3VLV2-26

0.9V1.16VLVCLK+27

1.09V1.17VLVCLK-28

0.9V1.07VLV3+29

1.09V1.27VLV3-30

0.9V1.02VLV4+31

1.09V1.3VLV4-32

RunLabelPin

Diode

Check

Open15.57VVDD41
Open15.57VVDD42

GndGndGnd43
Open6.86VVCOM_IN44
Open6.87VVCOM_FB45

GndGndGnd46

1.5V(-4.7V)VST47

0.6V(-5V)VGL48

1.5V(-4.8V)VDD_EVEN49

1.5V(-4.8V)VDD_ODD50

0.6V(-5V)VGI_P (VGL)51

Open27.4VVGI_N (VGH)52

Open1.06VGMA1813

GndGndGnd14

2.06V1.06VOPT_N15
Gnd1.07VH_CONV16

1.06V0VVST_IN17

1.06V0.62VPOL18

1.06V0.3VSOE19
GndGndGnd20

57

0.9V1.02VLV5+33

1.09V1.3VLV5-34
GndGndGnd35

1.64V3.3VVCC36

1.64V3.3VVCC37

GndGndGnd38

Open7.81VHVDD39
Open7.81VHVDD40

1.5V8VCLK653

1.5V8VCLK554

1.5V8VCLK455

1.5V8VCLK356

1.5V8VCLK257

1.5V8VCLK158

Open7.7VZ_OUT59

GndGndGnd60

October 2010 LCD TV 42LE5500

Main Board Connector P7501 to the Panel Voltage and Diode Check

Main Board Connector P7501 to the Panel Voltage and Diode Check

P7501 Connector “Main" to the “Panel“

RunLabelPin

Diode

Check

GndGndGnd1

Open7.7VZ_OUT2

1.5V8VCLK13

1.5V8VCLK24

1.5V8VCLK35

1.5V8VCLK46

1.5V8VCLK57

1.5V8VCLK68

Open27.4VVGH9

0.6V(-5V)VGH10

1.5V(-4.8V)VGH_ODD11

1.5V(-4.8V)VGH_EVEN12

There are no Stand-By Voltages for the Connector
Diode Mode values taken with all Connectors Removed

RunLabelPin

Diode

Check

Open7.81VHVDD21
Open7.81VHVDD22

GndGndGnd23

1.64V3.3VVCC24

1.64V3.3VVCC25

GndGndGnd26

1.09V1.07VRV0+27

0.9V1.12VRV0-28

1.09V1.13VRV1+29

0.9V1.23VRV1-30

1.09V1.13VRV2+31

0.9V1.22VRV2-32

RunLabelPin

Diode

Check

1.06V0.3VSOE42

1.06V0.62VPOL43

1.06V0VVST_IN44

2.06V1.06VOPT_N46

Open1.06VGMA1848
Open2.35VGMA1649
Open2.98VGMA1550
Open4.08VGMA1351
Open5.99VGMA1252

GndGndGnd41

Gnd1.07VH_CONV45

GndGndGnd47

0.6V(-5V)VGL13

1.5V(-4.7V)VST14

GndGndGnd15
Open6.87VVCOM_FB16
Open6.86VVCOM_IN17

GndGndGnd18

Open15.57VVDD19
Open15.57VVDD20

58

1.09V1.17VRVCLK+33

0.9V1.18VRVCLK-34

1.09V1.08VRV3+35

0.9V1.27VRV3-36

1.09V1.12VRV4+37

0.9V1.22VRV4-38

1.09V1.13VRV5+39

0.9V1.22VRV5-40

October 2010 LCD TV 42LE5500

Open7.48VGMA1053
Open8.02VGMA954
Open10.02VGMA755
Open11.88VGMA656
Open12.79VGMA457
Open13.5VGMA358
Open14.91VGMA159

GndGndGnd60

Main Board P8200 to (Ft. IR/Intelligent Sensor) Voltage and Diod

Main Board P8200 to (Ft. IR/Intelligent Sensor) Voltage and Diod

e Check

e Check

P8200 Connector "MAIN Board" To P100 "IR Board"

Pin

1
2
3
4
5
6
7
8
9

10

(1)

(1)

SCL
SDA

(2)

IR

Diode CheckRun STBYLabel

P8200

Open3.5V3.56V
Open3.5V3.56V

GndGndGndGnd

1.9V3.3V3.32VKEY 1

1.9V3.3V3.29VKEY 2

1.24V3.47V3.56V3.5V_ST
GndGndGndGnd

Open0V0VLED_LOGO
Open1.6V1.63V

GndGndGndGnd

1

11
12

(1)

Clock pulses only present when Intelligent Sensor is turned on. (3.7V p/p)

(2)

IR pulses (1.6V p/p)

Diode Mode values taken with all Connectors Removed

59

0.52V3.34V0V+3.3V_Normal

Open0V0VLED_R/BUZZ

October 2010 LCD TV 42LE5500

Main Board Connector P8800 to Speakers Voltage and Diode Check

Main Board Connector P8800 to Speakers Voltage and Diode Check

Q8800 (Mute) Active Low.
Normal 3.3V Collector to Pin 25

Use speaker out to test for defective Audio Amp IC8801

Note: (Normal, ½ Audio B+)

P8800 CONNECTOR "Main" to "Speakers"

Mute

Pin 25

Q8800

Amp Mute

IC8800

Amp

1.8V

LABEL

SPK-R(-)

SPK-R(+)

SPK-L(-)

SPK-L(+)

Diode CheckRunSBYPin

IC8801

Open10.62V0V1
Open10.62V0V2
Open10.62V0V3
Open10.62V0V4

Audio B+

21.3V

Pins 49-52

(1)

Diode Mode values taken with all Connectors Removed

60

P8800

October 2010 LCD TV 42LE5500

Main JK8700 Wireless Media Box Dongle Jack (Voltage and Diode Ch

Main JK8700 Wireless Media Box Dongle Jack (Voltage and Diode Ch

eck)

eck)

JK8700 "MAIN Board" To "Wireless Media Box Dongle"

Diode CheckRun STBYLabelPin

0.98V20.3V0V*20.3V1-6

Wireless Media Box Dongle

must be plugged in for

these voltages.

0.98V0.3V0VDetect7

1.2V3.3V0VInterrupt8
GndGnd0VGnd9

1.1V3.3V0Vn/c10
GndGnd0VGnd11

1.02V3.3V0VI2C_SCL12

1.02V3.3V0VI2C_SDA13
GndGnd0VGnd14

1.17V3.3V0VWireless_RX15

1.22V3.3V0VWireless_TX16
GndGnd0VGnd17

1.37V3.3V0.67VIR18
GndGnd0VGnd19-20

Diode Mode values taken

with all Connectors

JK8700

Jack

1

Removed

Voltages with Wireless Media Box Dongle plugged in. Use Media Box Dongle side to read voltages.

Remove cover, (see Wireless Media Box training manual for details).

*20.3V Switched from Q8701 Drain Back side of the board.

Q8701 turned on by Q8700 front side of the board.

Q8700 turned on by Microprocessor pin 38.

61

October 2010 LCD TV 42LE5500

FRONT (IR, INTELLIGENT SENSOR and MOVING LED) SECTION

FRONT (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 Soft Touch
Key Board and the Center LG Logo board. The Center LG Logo lights after power on and the picture
appears. Then dims down in about 2 seconds. At power off, it does the reverse.

The IR board receives it operating B+ via CON1 pin 6 (STBY 3.5V).

The IR (Infrared) remote receiver can be measured (1.57V) at pin 9 of connector CON1 or P8200 on
the Main board in Stand-By. During run pin 9 reads (1.54V).

The IR pulses (1.6V p/p) CON1 pin 9 are sent to P8200 on the Main board and on to the
Microprocessor (IC8101) via pin 16.

The Intelligent Sensor communicates with the Micro/Video Processor IC900 BCM Chip via clock and
data lines SCL1 and SDA1 arriving on connector CON1 from P8200 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 Soft Touch Key board.

The Key board is routed to the IR board via CON2 and output on CON1 Key 1 and Key 2 lines,
(Key 1 pin 4 and Key 2 pin 5). Arriving at P8200 pins 4 and 5 on the Main Board.
Then to the Microprocessor 25 and 26 lines.

62

October 2010 LCD TV 42LE5500

Front IR Board (Connections Identified)

Front IR Board (Connections Identified)

(1)

J3

To Center

Logo Board

p/n EBR64966201

J2

To Soft Touch

Key Board

IR and Intelligent

Sensor board

63

J1

To Main Board

October 2010 LCD TV 42LE5500

Front Board Connectors CON1, CON2 and CON3 Voltage and Diode Ch

Front Board Connectors CON1, CON2 and CON3 Voltage and Diode Ch

eck

eck

CON1 "Front IR" to P8200 " MAIN"

Run STBYLabelPin

(1)

SCL1

(1)

SDA2

(2)

IR9

Diode

Check

Open3.5V3.56V
Open3.5V3.56V

GndGndGndGnd3

1.9V3.3V3.32VKEY 14

1.9V3.3V3.29VKEY 25

1.24V3.47V3.56V3.5V_ST6
GndGndGndGnd7

Open0V0VLED_LOGO8
Open1.6V1.63V

GndGndGndGnd10

CON2 "Front IR" to “Soft Touch Key Board"

Diode CheckRun STBYPin

Open3.47V3.56V1
Open1.63V0V2

GndGndGnd3
Open3.5V3.56V4
Open3.5V3.56V5

GndGndGnd6

1.9V3.3V3.32V7

1.9V3.3V3.29V8

CON3 "Front IR" to “LG Logo Board"

(1)

Clock pulses only present when Intelligent Sensor is

turned on. (3.7V p/p)

(2)

IR pulses (1.6V p/p)

Diode Mode values taken with all Connectors Removed

0.52V3.34V0V+3.3V_Normal11
Open0V0VLED_R/BUZZ12

64

October 2010 LCD TV 42LE5500

Diode CheckRun STBYPin

1.24V3.47V3.56V1
GndGndGnd2

Open0.6V1.36V3

GndGndGnd4

INVISIBLE SPEAKER SECTION

INVISIBLE SPEAKER SECTION

Speaker

The 42LE5500 contains the Invisible Speaker system.
The Full Range Speakers point downward, so there is no front viewable speaker grill or air ports.

Installed

Top View

p/n EAB60961501

Side View

Front View

65

October 2010 LCD TV 42LE5500

INTERCONNECT DIAGRAM (11 X 17 FOLDOUT SECTION)

INTERCONNECT DIAGRAM (11 X 17 FOLDOUT SECTION)

This section shows the 11X17 foldout that

This 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 Tr

aining Manual.

The Adobe version of this Training Manual allows the viewer to

The Adobe version of thi

s Training Manual allows the viewer to

zoom in and out making reading of the small text easier.

zoom i

n and out making reading of the small text easier.

This Power Point shows a graphical representation o

f the 11 X 17

This Power Point shows a graphical representation of the 11 X 17

foldout page so clarity

is limited.

foldout page so clarity is limited.

66

October 2010 LCD TV 42LE5500

P204 "SMPS" To “The Panel"

Pin Label STBY Run Diode Check

12 02.A 0V 117.8V Open
11 n/c n/c n/c Open
10 02-1C 0V 1V~30V Open

9 02-2C 0V 1V~30V Open
8 02-3C 0V 1V~30V Open

7-6 n/c n/c n/c Open

5 01-3C 0V 1V~30V Open
4 01-2C 0V 1V~30V Open
3 02-1C 0V 1V~30V Open
2 n/c n/c 0V Open
1 01.A 0V 117.8V Open

SMPS BOARD

p/n: EAY60803101

Components

Inside

Dashed Line

are Hot Ground

16uF/450V

F101-F103

Hot Gnd
Stby 7.6V

Q602

E

Run 396V

B

C

Indicates Hot

Ground

Front pins on connector
are odd numbers.

P201

P201

Front pins on connector
are odd numbers.

SMPS TEST 1

SMPS TEST 2

21uF/450V

21uF/450V

21uF/450V

21uF/450V

L601

D601

BD101

STBY 3.5V

12V

12V

STBY 3.5V

12V12V

STBY 3.5V

INV-ON

B

STBY 3.5V

12V12V

P205 "SMPS" To “The Panel"

Pin Label STBY Run Diode Check

12 04.A 0V 120V Open
11 n/c n/c n/c Open
10 04-1C 0V 1V~30V Open

9 04-2C 0V 1V~30V Open
8 04-3C 0V 1V~30V Open

7-6 n/c n/c n/c Open

5 03-3C 0V 1V~30V Open
4 03-2C 0V 1V~30V Open
3 03-1C 0V 1V~30V Open
2n/c n/c 0V Open
1 03.A 0V 120V Open

B

IC104
IC105

CE

Q207

T102

Inverter

D206

T101

F101

21uF/450V

3.15A

21uF/450V

250V

F103

250V

1A

L602

D601 Q602

+

-

RL101

RL102

R149

R149

SMPS TEST 1: To Force
Power Supply On.
Disconnect P8000 on Main
board.

24V24V

(A) Jump pins 9, 10, 11 or 12

4 28 612 1016 1420 18222324

(3.5V) to pin 1. (Test Voltage

3 17 511 915 1319 1721

Outputs 12V, 24V to Main and

24V

PWR ON

24V to both Inverters). Remove

A

AC power.
Leave the jumper in place.

SMPS TEST 2: (B) Jump pins
9, 10, 11 or 12 (3.5V) to pin 18
(INV-ON). Apply AC power, the
Backlights should turn on.

24V24V

Note; If there is a problem with

4 28 612 1016 1420 18222324

a load on the Inverter you can

3 17 511 915 1319 1721

Remove AC and Disconnect

24V

PWR ON

P205 or P204. When AC is

A

reapplied, the Backlight LEDs
should turn on for about 6
seconds and then shut off.

Q203

-

LED

Power

+

120V

D204
D203
D202
D201

T501

IC501

16uF/450V

F102

SK101

AC In

Note: If a particular area is exhibiting a dimmer
backlight level than other areas or the overall
brightness seems dim, be sure to first check the
customer’s Menu setting for Backlights. Raise the
percentage and see if the overall brightness returns
to normal. If not,

st

1

: Check the P-DIM level, it should rise with the
percentage shown on screen. 100%, 3.3V. Follow
the P-DIM signal all the way to the Inverter.

nd

2

: Turn off Local Dimming in the Customers
Menu. If the brightness returns to normal, examine
the signals required for Local Dimming.
(SIN, V-SYNC and SCLK).

See the Inverter Section

Blow Up on the Right

P204

To the Panel

P205

C

E

B

250V

P201

1A

P201 "SMPS" To P8000 "MAIN Board"

Pin Label STBY Run

24 ERROR 0V 0V 1.45V
23 L-DIM (SIN) 0V 3.3V Open
22 P-DIM 0V 0.38V~3.3V Open
21 12V 0V 11.43V 0.178V
20 SCLK 0V 0.09V Open
19 12V 0V 11.43V 0.178V
18 INV-ON 0V 3.28V Open

IC502

IC503

Q511

17 12V 0V 11.43V 0.178V
16 V-SYNC 0V 0.02V Open

13-15 Gnd Gnd Gnd Gnd

E

C

B

9-12 3.5V 3.57V 3.5V Open

5-8 Gnd Gnd Gnd Gnd
2-4 24V 0V 21.27V 1.10V

F100

1 PWR-ON 0V 3.36V 1.02V

5A

(1)

250V

PDIM Pin 22 can vary according to incoming video IRE level,
OSD Backlight setting and then Intelligent Sensor (room light
condition) Output from the Video Processor IC900.
Range 0.37V to 3.3V.

J3

IR Receiver

Intelligent

Sensor

LG Logo

42LE5500 INTERCONNECT DIAGRAM

You can also these each of the 12
blocks functionality by grounding the
driver output signals. See “Forcing on
a Block of LEDs on the right.

J3 "IR Board" To
"Center Logo Board"

J2

Pin STBY Run Diode

Front IR

Front “Soft Switch” Keys

1 3.45V 3.0V 1.5V
2 Gnd Gnd Gnd
3 1.36V 0.64V Open
4

J1

J2 "IR Board" To "Soft Touch Key Board"
Pin STBY Run Diode

Gnd Gnd Gnd

1 3.45V 3.36V Open
2 0V 1.63V Open
3 Gnd Gnd Gnd
4 3.3V 3.3V Open

Diode Check

P8000

Diode

Gnd

1.05V
Open
Open

1.06V
Open

1.62V
Open

1.06V

Gnd

1.24V
Open
Open
Open

Pin STBY Run Diode

5 3.28V 3.28V Open
6 Gnd Gnd Gnd
7 3.45V 3.36V Open
8 3.45V 3.36V Open

1 VDD-33 3.5V
2 VLED-RANGE 0V
3Gnd Gnd
4 +12VS 12.44VPin 17-19-21 P201
5Gnd Gnd
6+3.5VS3.57VPin 9-12 P201

1 INV_ON 3.28VPin 18 P201
2Gnd Gnd
3Gnd Gnd
4 SCLK 0.09VPin 20 P201
5 FB_STR_VF 1V
6 P-DM1 1.9VPin 22 P201

1 Error 0VPin 24 P201
2(L-DIM) SIN 3.3VPin 23 P201
3 POWER_ON 3.35VPin 1 P201
4 VSYNC_IN 0VPin 16 P201
5Gnd Gnd
6Gnd Gnd

S-CLK Pin 23 P201

3.25V p/p

Local Dimming On

S-CLK Pin 23 P201

3.25V p/p

Local Dimming Off

SCLK Pin 20 P201

3.76V p/p

V-SYNC Pin 16 P201

3.64V p/p

P8800 "Main" To "Speakers"

Label

Pin SBY Run

1 SPK-R(-) 0V 12.3V Open
2 SPK-R(+) 0V 12.3V Open
3 SPK-L(-) 0V 12.3V Open
4 SPK-L(+) 0V 12.3V Open

Intelligent Sensor
Intelligent Sensor

Stand-by

The Panel contains 12 LED Blocks

To force a Block to turn on, simple ground
the pin providing the 13V source is present.

INVERTER SECTION

OF THE SMPS

Gnd

Forcing on

A Block of LEDs.

SW9300

These drivers ground the LED blocks. (12 Total). If the 120V is present on Pins 1 and

X9300
25Mhz

IC9300

Tru-

SW9300

Motion
Reset

IC9000

X9000
12Mhz

n/c

P9000

Micro

Reset

Video

Reset

IC8100

X8100

Q8308

Micro

Q8800

SW8100

SW1000

IC8801

Diode

To Speakers

P8200 "MAIN Board" To J1 "IR Board"

Pin Label STBY Run

1 SCL 3.56V 3.5V Open
2 SDA 3.56V 3.5V Open
3 Gnd Gnd Gnd Gnd
4 Key1 3.32V 3.3V 1.9V
5 Key2 3.29V 3.3V 1.9V
6 3.5V_ST 3.56V 3.47V 1.24V

Q8700

IC8700

P8800

Diode Check

1V (100 IRE)

Gnd

30V (0 IRE)

B

E

B

E

B

E

B

E

B

E

B

E

B

E

B

E

B

E

B

E

B

E

B

E

C

C

C

C

C

C

C

C

C

C

C

C

P204

P205

*White 100 IRE to Black 0 IRE

12 of P204 and P205 you can ground these test points to turn on a block.

To the Panel

P7501 P7500

IC9001

IC9301

IC9003

LG5111

IC9001
T-CON

IC8900

SW8100

IC1000

SW1000

IC8804

IC8300

D

HDMI
Select

Q8304

IC8400

D8307

Q8303

Q8300

D8309

Q8302

Q8200

Q8305

D8306

P8200

Pin Label STBY Run

7GndGndGndGnd
8LED_LOGO

9 IR 1.63V Open

10 Gnd Gnd Gnd

3.3V_Normal

11
12 LED_BUZZ 0V Open

D8312

IC8101

L8805L8804

Q8701

Q8205

X8101

D
GSB

IC8800

LAN

Q?

LGE7378A

32.768Khz

Q200

S

G

Q8301

Q8201

Q8203

IC9100

L9100

IC9103

A

A-C

D9101

C

A

A-C

D9102

C

IC9302

L9301

IC8901

L8904

IC604

IC605IC603

IC606

IC900

Video Processor

LGE3549XQ

MAIN BOARD

p/n: EBU60904603

IC8200

IC8401

0V

0V Open

1.6V
Gnd

0V 0.59V

3.34V
0V

IC9102

L9102

Q8003

L9101

IC8902

L8012

IC602

Diode Check

To The Panel

120V

n/c

*1V~30V LED Drive

n/c

*1V~30V LED Drive

n/c

120V

120V

n/c

*1V~30V LED Drive

n/c

*1V~30V LED Drive

n/c

120V

P8000

Q8005

Q8000

Q8004

D

Q8001

G

S

2

Q8008

Q8007

IC8903

L8905

IC8202

L8009

P9000

Gamma

IC8000

Q901

L8004

IC901

54MHz

IC700

IC300

Q300

TDVJ-H031F

Digital Video

Q702

Q701

Tuner Data
Tuner Clock

Tuner B+

1

2

3

X1001

TU700

18. IF p

17. IF n

16. IF AGC

15. Reset

14. 3.3V

13. 1.26V

12. GND

11. CVBS

10. NC

9. SIF

8. NC

7. SDA

6. SCL

5. NC

4. NC

3. 5V

2. NC

1. NC

1
2

Q8002

1

3

IC8001

3

IC8003

IC302

IC8005

L8015

L8010

Component
Composite

Analog
Audio

HDMI

D8310

32V p/p 120Hz

32V p/p 120Hz

Drive Signals

to LED Blocks

IC301

USB1

USB2

HP

A1

A2

C

80 IRE

5 IRE

42LE5500 MAIN (FRONT SIDE) SIMICONDUCTORS

IC700 (+1.26V_TU) IC8002 (D1.8V) IC8005 (+3.3V_NORMAL) IC8902 (+1.26V_MEMC) IC9102 DC to DC Q8003 PANEL_VCC Q8700 Wireless PWR

Pin Regulator Pin Regulator Pin Regulator Pin Regulator Pin HVDD T-CON Pin

[1] 0V (Gnd) [1] 5V [1] 0V (Gnd) [1] 0V (Gnd) [1] 0V (Gnd) B 0.679V B 0.66V
[2] 1.26V (Out) [2] 3.34V (In) [2] 11.8V (In) [2] 11.8V (In) [2] 11.72V (In) C 0V C 0.14V
[3] 3.3V (In) [3] 1.8V (Out) [3] 0V (Gnd) [3] 0V (Gnd) [3] 11.72V (In) E Gnd E Gnd

IC1000 SOC Reset [5] Gnd [5] 0.86V [5] 0.7V [5] 3.2V Q8004 PANEL_VCC Q8700 Wireless PWR

Pin Generator [6] 0.9V [6] 3.36V (PWR On/Off2 Ctl) [6] 3.36V (PWR On/Off2 Ctl) [6] 0V Pin Switch Dongle In Turns on Q8701

[1] 3.32V (In) [7] 0.9V [7] 3.36V (Out) [7] 1.3V (Out) [7] 0V S 11.8V (In) B 0.0V
[2] 0V (Gnd) [8] 1V [8] 3.36V (Out) [8] 1.3V (Out) [8] 11.7V G 1.8V (Enable) C 24V
[3] 3.3V (Out) [9] 2.38V [9] 0V (Gnd) D 11.8V (Out) E Gnd

IC8000 5V Regulator Pin (+12V and +3.5V) Pin Regulator [11] 0V (Gnd) Q8005 INV_ON Q8800 AMP_MUTE

Pin for USB IC8003 (+5V_NORMAL) [1] 0V (Gnd) [1] 0V (Gnd) [12] 0V (Gnd) Pin Driver Pin Pin 25 IC8801

[1] 11.79V (In) Pin Regulator [2] 3.6V (In) [2] 11.8V (In) [13] 0V (Gnd) B 0V (INV ON) En B 0V
[2] 5V (Out) [1] 0V (Gnd) [3] 3.5V (Out) [3] 0V (Gnd) [14] 7.7V C 3.1V (Out) C 3.336V
[3] 5V (Out) [2] 11.8V (In) [4] 0.8V [15] 7.7V (HVDD) E Gnd E Gnd
[4] 10.5V [3] 0V (Gnd) IC8008 Power Det Gen [5] 0.8V [16] 0V (Gnd)
[5] 3.3V [4] 0.8V Pin (+24V) [6] 3.36V (PWR On/Off2 Ctl) Q8200 IR Buffer D9101 VGH/VDD
[6] 0.8V [5] 0.86V [1] 0V (Gnd) [7] 3.3V (Out) IC9300 Reset for Pin 2nd Pin Rectifyer
[7] 4.99V [6] 3.37V (PWR On/Off2 Ctl) [2] 3.6V (In) [8] 3.3V (Out) Pin LG5111 B 0.02V A 15.4V

[8] 0V (Gnd) [7] 5V (In) [3] 3.7V (Out) [1] 3.32V (In) C 3.4V AC 22.2V

IC8001 D1.2V and A1.2V IC8800 (+1.8V_AMP) Pin Chip [3] 3.34V (Out)

Pin Regulator IC8004 A2.5V Regulator Pin Regulator [1] 3.3V Q8201 IR Buffer D9102 VGL/VCC

[1] 0V (Gnd) Pin for USB [1] 0V (Gnd) [2] 0V (Gnd) IC9302 (1.8V_L/Dimming) Pin 1st Pin Rectifyer
[2] 3.3V [1] n/c [2] 1.8V (Out) [3] 3.3V (In) Pin Regulator B 0V A (-5V VGL)
[3] 0V (Gnd) [2] 3.26V (In) [3] 3.295V (In) [4] 0V (Gnd) [1] 0V (Gnd) C 3.3V AC (-1.9V)
[4] 1.2V [3] 3.26V (In) [5] 6.8V [2] 11.8V (In) E Gnd C 0V
[5] 3.3V [4] n/c IC8901 (+1.5V_MEMC) [6] 6.8V [3] 0V (Gnd)
[6] n/c [5] n/c Pin Regulator [7] 15.3V [4] 0.8V Q8306 HDMI
[7] 4.46V [6] 2.55V (Out) [1] 0V (Gnd) [8] 15.3V [5] 0.76V Pin Det

[8] 3.3V [7] 0.8V [2] 1.5V (Out) [9] n/c [6] 3.34V (PWR On/Off2 Ctl) B 0V

[9] 3.3V [8] 0V (Gnd) [3] 3.3V (In) [10] 13.47V [7] 1.8V (In) C 3.3V
[10] 3.3V [11] 12.75V [8] 1.8V (In) E Gnd
[11] 1.2V [12] 11.8V
[12] Gnd [13] 10V Q8001 PANEL_VCC Q8307 HDMI
[13] 3.3V [14] 5.96V Pin Control 1st Driver Pin Det
[14] 0.8V [15] 4.06V B 0V B 0V

[4] Gnd [4] 0.8V [4] 0.8V [4] 3.25V

[10] 3.36V (PWR On/Off1 Ctl) IC8007 Power Det Gen IC8903 (+3.3V_MEMC) [10] 1.13V

[8] 5V (In) IC9100 P-GAMMA [2] 0V (Gnd) E Gnd C 27.4V (VGH)

[16] 15.3V C 0.68V C 4.18V
[17] 0V E Gnd E Gnd
[18] 2.96V
[19] 2.33V
[20] 3.3V (In)

Control 2nd Driver Dongle Out Turns on Q8701

42LE5500 MAIN (BACK SIDE) SIMICONDUCTORS

IC602 D1.8V IC8200 RS232 IC8401 EDID Data IC9303 EEPROM Q8000 RL_ON (PWR_On) Q8303, 4, 5 HDMI 3

Pin Regulator Pin Routing Pin PC Pin for LG5111 Pin 1st Driver Pin Det

[1] 0V (Gnd) [1] 0V [1] 0V (Gnd) [1] 0V (Gnd) B 0.66V B 0V

[2] 3.29V (PWR On/Off1 Ctl) [2] 0V [2] 0V (Gnd) [2] 0V (Gnd) C 0V C 4.2V

[3] 0.9V (DDR_VTT) [3] 0V [3] 0V (Gnd) [3] 0V (Gnd) E Gnd E Gnd

[4] 0.93V [4] 0V [4] 0V (Gnd) [4] 0V (Gnd)

[5] 1.83V [5] 0V [5] 0.7V [5] 3.37V Q8002 PWR_ON Q8308 CEC Remote

[6] 3.38V (In) [6] (-5.47V) [6] 4.1V [6] 3.37V Pin Switch Pin HDMI CEC

[7] 1.8V (Out) [7] n/c (5.59V) [7] 4.5V [7] 3.34V [1] 3.36V (In) [B] 2.72V

[8] 0.91V (DDR_VTT) [8] n/c (0V) [8] 4.5V (In) [8] 3.37V (In) [2] 0V [G] 2.73V

IC8100 EEPROM [10] n/c (0.2V) IC8700 Wireless Q200 (1.8V_HDMI) [D] 3.37V

Pin Micro [11] n/c (3.3V) Pin Buffer Pin Switch Q8203 IR Wireless Pass D8312 3.5V Pull Up

[1] 0V (Gnd) [12] 3.35V [1] 0V (3.3V Dongle In) S 1.83V (Out) Pin 2nd Driver Pin HDMI CEC

[2] 0V (Gnd) [13] 0V [2] 3.3V (0.3V Dongle In) G 3.35V (PWR On/Off2 Ctl) B 0V A1 0V

[3] 0V (Gnd) [14] (-5.47V) [3] n/c D 1.83V (In) C 3.3V C 3.26V

[4] 0V (Gnd) [15] 0V (Gnd) [4] n/c E Gnd A2 3.2V

[5] 3.37V [16] 3.37V [5] n/c Q701 Tuner SIF

[6] 3.37V [6] Gnd Pin (Sound) Buffer D8306, 7, 9 5V Pull Up Routing

[7] 0V (Gnd) IC8400 RGB [7] Gnd B 0.16V Q8205 IR Wireless Pass Pin HDMI SCL/SDA

[8] 3.37V Pin H/V Sync [8] Gnd C Gnd Pin 1st Driver A1 5.04V

[9] n/c (3.3V)

[1] 1.9V [9] n/c E 0.83V B 0.6V C 4.58V
[2] 1.9V [10] 0.02V C0V A20V
[3] 4.4V [11] 0V Q702 Tuner Video E Gnd
[4] 0V [12] 3.3V Pin (Analog) Buffer
[5] 0.9V [13] 0V (3.3V Dongle In) B 2.05V Q8300, 2 HDMI 2
[6] n/c (4.5V) [14] 3.3V C 2.75V Pin Det
[7] 0V (Gnd) [15] 3.3V E Gnd B 4.2V

[8] n/c (4.5V) [16] 3.3V C0V

[9] n/c (1.9V) Q901 FLASH_WP E Gnd
[10] n/c (1.9V) IC9000 Serial Flash Pin for IC901
[11] n/c (4.5V) Pin T-CON B 0V (Flash_WP)
[12] 0.9V [1] 0.06V C 3.36V
[13] 0.9V [2] 0.67V E Gnd
[14] 5V [3] 3.3V (In)

[4] 0V (Gnd)
[5] 0V
[6] 0.34V
[7] 3.31V (In)

[8] 3.34V (In)

[3] 3.3V (Out) [S] 3.27V

42LE5500

42LE5500

Conclusion

Conclusion

Page

Page

Direct View LCD

Direct View LCD

This concludes the

42LE5500

training session.