LG 47LB1DA 1080p LCD, 47LB1DA Training Manual

TRAINING MANUAL

47LB1DA 1080p LCD

Spring 2007

Service

Digital Display

Published February 2006 by LG Education & Product Engineering
Customer Service (and Part Sales): 1-800-243-0000
Technical Support (and Part Sales): 1-800-847-7597
USA Website: www.lgusa.com
Customer Service Website: us.lgservice.com
B2B Service Website: aic.lgservice.com
Training Website: www.LGCSAcademy.com

IMPORTANT SAFETY NOTICE

This manual was prepared for use only by properly trained audio-visual service technicians. 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. All components should be replaced only with types identical to those in the original
circuit and their physical location, wiring, and lead dress must conform to original layout upon completion of repairs. If any fuse (or Fusible
Resistor) in this TV receiver is blown, replace it only with the factory specified fuse type and rating. When replacing a high wattage resistor (Oxide
Metal Film Resistor, over 1W), keep the resistor 10mm away from PCB. Always keep wires away from high voltage or high temperature parts. Do not
attempt to modify this product in any way.

Special components are also used to prevent shock and fire hazard and are required to maintain safe performance. No deviations are allowed
without prior approval by LG Electronics. Service work should be performed only after you are thoroughly familiar with these safety checks and
servicing guidelines. Circuit diagrams may occasionally differ from the actual circuit used. This way, implementation of the latest safety and
performance improvement changes into the set is not delayed until the new service literature is printed.

GENERAL SAFETY GUIDANCE

An lsolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC power line. Use a
transformer of adequate power rating to protect against personal injury from electrical shocks. It will also protect the receiver and its components
from being damaged by accidental shorts of the circuitry that may be inadvertently introduced during the service operation. Before returning the
receiver to the customer, always perform an AC leakage current check on the exposed metallic parts of the cabinet, such as antennas, terminals,
etc., to be sure the set is safe to operate without damage of electrical shock.

With the instrument AC plug removed from AC source, connect an electrical jumper across the two AC plug prongs. Place the AC switch in the on
position, connect one lead of ohm-meter to the AC plug prongs tied together and touch other ohm-meter lead in turn to each exposed metallic
parts such as antenna terminals, phone jacks, etc. If the exposed metallic part has a return path to the chassis, the measured resistance should be

between 1MΩ and 5.2MΩ. When the exposed metal has no return path to the chassis the reading must be infinite. Any other abnormality that
exists must be corrected before the receiver is returned to the customer.

ELECTROSTATICALLY SENSITIVE DEVICES

Some semiconductor (solid-state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically
Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor “chip” compo­nents. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.

Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on the body
by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be
removed for potential shock reasons prior to applying power to the unit under test. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such as an ESD mat, to prevent electrostatic charge buildup or exposure of the assembly. Use
only a grounded-tip soldering iron to solder or unsolder ES devices. Use only an anti-static solder removal device. Some solder removal devices
not classified as “anti-static” can generate electrical charges sufficient to damage ES devices. Do not use freon-propelled chemicals which can
generate electrical charge sufficient to damage ES devices. Do not remove a replacement ES device from its protective package until immediately
before you are ready to install it. Minimize bodily motions when handling unpackaged replacement ES devices (Otherwise, seemingly harmless
motion, such as the brushing together of your clothing or the lifting of your foot from a carpeted floor, can generate static electricity sufficient
to damage an ES device).

REGULATORY INFORMATION

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation. This
equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may
cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on,
the user is encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate the receiving antenna;
Increase the separation between the equipment and receiver; Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected; Consult the dealer or an experienced radio/TV technician for help.

The responsible party for this device’s compliance is:

LG Electronics of Alabama, Inc.
201 James Record Road
Huntsville, AL 35824, USA
Digital TV Hotline: [phone]

TABLE OF CONTENTS

OVERVIEW ............................................................................................................. 5

INTRODUCTION .................................................................................................... 5

XD ENGINE .......................................................................................................... 5

COMPUTER CONNECTION ........................................................................................ 5

SERIAL NUMBER STRUCTURE .................................................................................. 6

LOCK SYSTEM ...................................................................................................... 6

SET PASSWORD .................................................................................................... 7

MOUNTING INTERFACE .......................................................................................... 7

SERVICE MENU .................................................................................................... 8

SERVICE REMOTE ................................................................................................. 9

THEORY ............................................................................................................... 1 1

LIQUID CRYSTAL DISPLAY .................................................................................... 11

LIQUID CRYSTAL PANEL ....................................................................................... 12

CIRCUIT DESCRIPTIONS ......................................................................................... 1 3

POWER SUPPLY .................................................................................................. 13

POWER SUPPLY SPECS ......................................................................................... 14

VIDEO .............................................................................................................. 15

AUDIO ............................................................................................................. 16

I2C FLOWCHART ................................................................................................ 18

TROUBLESHOOTING ............................................................................................... 20

TEST POINTS ..................................................................................................... 20

POWER SUPPLY RESISTANCE READINGS ................................................................... 21

LED INDICATORS ................................................................................................ 22

NO POWER ........................................................................................................ 23

POWER SUPPLY SCHEMATIC .................................................................................. 25

POWER SUPPLY - DEEP SLEEP MODE ....................................................................... 26

POWER SUPPLY - RUN 160VDC & REGULATED 383VDC ............................................... 27

POWER SUPPLY - AC DETECT & RELAY CONTROL ........................................................ 28

POWER SUPPLY - 24VDC & 19VDC SUPPLY .............................................................. 29

POWER SUPPLY - 6VDC & 12VDC SUPPLY ................................................................ 30

DEFECTIVE COMPONENT ....................................................................................... 31

DEFECTIVE HDMI ............................................................................................... 32

DEFECTIVE RF .................................................................................................... 33

DEFECTIVE RF 2 ................................................................................................. 34

DEFECTIVE RF 3 ................................................................................................. 35

DEFECTIVE DIGITAL ............................................................................................ 36

NO AUDIO - COMPOSITE & COMPONENT .................................................................. 37

NO AUDIO - HDMI .............................................................................................. 37

NO AUDIO - RF .................................................................................................. 38

NO AUDIO - DIGITAL ........................................................................................... 38

NO AUDIO - GENERAL .......................................................................................... 39

CABLECARD ....................................................................................................... 40

DISSASEMBLY ....................................................................................................... 43

EXPLODED VIEW ................................................................................................. 43

BACK CABINET REMOVAL ...................................................................................... 44

BOARD DESCRIPTIONS ......................................................................................... 45

FRAME REMOVAL ................................................................................................ 47

Directview LCD Training 3 Contents

- 4 -

OVERVIEW

INTRODUCTION

All LCD TV models are module level repair in and out of
warranty. They are covered by a one year parts and labor
warranty. Refer to the last page of the owner’s manual for
more warranty information. For models under 30”, the Sevice
Level is Factory Service Repair. Larger models are Field Service.
Contact the Warranty department for more information.

Some PC Resolutions

Resolution

800x600 60Hz
800x600 72Hz

800x600 75Hz
1024x768 60Hz
1024x768 70Hz
1024x768 75Hz
1280x768 60Hz
1360x768 60Hz

Vertical

Frequency (Hz)

COMPUTER CONNECTION

A computer can be connected to the RGB (VGA) or HDMI 1 connection
on the TV. The HDMI connection will require a DVI to HDMI adapter if
the PC has a DVI connector.

Set the monitor output resolution and vertical frequency on the PC
before connecting it to the TV. When using RGB (VGA), the TV input
will have to be changed from RGB-DTV to RGB-PC in the main input
menu option. This is not required on the HDMI conection since it is
auto sensing. If the message “OUT OF RANGE” appears on the screen,
adjust the PC output to a format listed in the chart.

OVERVIEW

47LB1DA

1920x1080p Resolution

NTSC/ATSC/QAM w/CableCARD

HDMI with HDCP x2

RGB (VGA) & RS-232

TM

XD ENGINE

XD is LG Electronic’s unique picture improving technology using an advanced digital signal processing
algorithm. When selecting EZ Picture options (Daylight, Normal and Night time), XD is automatically
changed to Auto. When selecting EZ Picture options (User 1 and User 2), you can choose the Auto/
Manual. When selecting Manual, you can adjust XD Contrast, XD color, and XD Noise.

1) Press the MENU button and then use the up or down arrows to select the VIDEO menu.

2) Press the right arrow and then use the up or down arrows to select XD.

3) Press the right arrow and then use the up or down arrows to select Auto or Manual.

Manual:

ˆ XD Contrast: Optimize the contrast automatically

according to the brightness of the reflection.

ˆ XD Color : Adjust the colors of the reflection

automatically to reproduce natural colors as closely
as possible.

ˆ XD Noise: Removes the noise up to the point where

it does not damage the original picture.

Use the use the up or down arrows to select On or Off.

4) Press Exit button to return to TV viewing or press MENU
button to return to the previous menu.

EZ Picture

Color Temperature

XD

Advanced

Video Reset

Manual

XD Contrast On

XD Color On

XD Noise On

Directview LCD Training 5 Overview

OVERVIEW

g

)

SERIAL NUMBER STRUCTURE

123 45 67 891011121314

\____/ \__/ \__/ \______________/

à Sequential Number (XXXXXXX),

5 to 7 digits (Number or Alphabet)

à Secret Code (VV)

, 2 digits (Alphabet)

à Production Site (SS), 2 digits (Alphabet)

à Last digit of Year and Month for Production (YMM), 3 digits (Number)

[Example] 403MXXQ05106

1 2 3 4 5 6 7 8 9 10 11 12 13 14 -----14 digit format
4 0 3 MXXQ 0 5 1 0 6 -------12 digit format
\____/ \__/ \__/ \______________/

à 05106: Sequential Number

à XQ: 2-Secret Code

à MX: Production Site (produced at LGEMX in Mexico)

à 403: Last di

it of Year and Month for Production(manu. In March 2004

LOCK SYSTEM

Enables or disables the blocking scheme you set up
previously.

1) After inputting the password, use the up or down
arrows to choose Lock System.

2) Press the right arrow and then use the up or down
arrows to select On or Off. When you select On, the
Lock System is enable.

3) Press EXIT button to return to TV viewing or press
MENU button to return to the previous menu.

Directview LCD Training 6 Overview

Lock System

Set Password

Block Channel

Movie Rating

TV Rating-Children

TV Rating-General

Input Block

Off

On

OVERVIEW

Lock System

Set Password

Block Channel

Movie Rating

TV Rating-Children

TV Rating-General

Input Block

New

Confirm

****

****

SET PASSWORD

Change the password by inputting a new password twice.

1) After inputting the password, use the up or down
arrows to choose Set password.

2) Press the right arrow and then choose any 4 digits
for your new password.

As soon as the 4 digits are entered, re-enter the
same 4 digits on the Confirm. Then your changed
password has been memorized.

3) Press EXIT to return to TV viewing or press MENU to
return to the previous menu.

NOTE: If you ever forget your password, key in ‘7’, ‘7’, ‘7’, ‘7’ on the remote control.

MOUNTING INTERFACE

The Video Electronics Standards Association (VESA) Flat Display Mounting Interface Standard (FDMI)
outlines mounting interface standards for flat-panel displays. This monitor uses a VESA standard so
most universal wall mounts for Plasmas and large LCDs will work.

3
1

2
3
1

Mounting Hole

37LZ30 32LC2D 37LC2D 32LP1D 37LP1D 42LP1D 55LP1D
A 664.2 682.1 762 570 643.1 725.5 840 1078.5 1173.7
B 220.5 302.6 169 408 275 345 406 287.4 339.7
C 580 200 600 200 600 600 800 600 600
D 269 100 400 100 400 400 400 400 400

E

F 61 60 62 68.8 86 116.1 103.7 71.3 94.1
G 81.5 74 78 135.8 110 103 59.7 85 74.8
HM5M4M6M4M5M5M5M6M6

J131412141414141313

VESA NO YES YES YES YES YES YES YES YES

E1:149.5

E2:200

580*269 200*100 600*400 200*100 600*400 600*400 800*400 600*400 600*400

E1:189.2
E2:227.2

E1:112.5

E2:141

E1:117

E2:142.3

E1:146.4

E2:187.4

E1:203.5

E2:274.5

42LB1DR

E1:112.4
E2:157.5

47LB1DA

E1:136.1

E2:182.6

Top View

Side View

A

CB B

Back View

E1

D

E2

G

F

Screw Hole

H

Directview LCD Training 7 Overview

OVERVIEW

SERVICE MENU

CALIBRATION MENU

Input

Pic. Mode

1. Contrast

2. Brightness

3. Color

4. Tint

5. Sharpness

6. R. Gain

7. G Gain

8. B Gain

9. R Offset

10. G Offset

11. B Offset

POS/SIZE ADJUST

1. H Position

2. V Position

3. H Size

4. V Size

Default Load
Count : 6

DTV

90
50
50
0
50
192
147
97
64
64
64

0
0
0
0

EXPERT MODE

Hold the MENU Key until

ENTER PASSWORD appears on the

screen, Press remote key sequence 8-7-4-1

1 2 3

4 65

7 8 9

-

A custom installer can calibrate the TV to the

viewing environment and the viewer’s

preferences then lock it in so the settings

cannot be altered without the code

FLASHBK

0

Note: Horizontal and Vertical controls only work with the TV, CTV, AV1, and AV2 sources.

Directview LCD Training 8 Overview

OVERVIEW

SERVICE REMOTE

NUM KEY FUNCTION
1 POWER To turn the TV on or off
2 POWER ON To turn the TV on automatically if the power is supplied to the TV. Use the POWER key to deactivate; It

should be deactivated when deli vered.
3 MUTE To activate the mute function.
4 P-CHECK To check TV screen image easily.
5 S-CHECK To check TV screen sound easily
6 ARC To select size of the main screen (Norm al, Spectacle, Wide or Zoom)
7 CAPTION Sw itch to closed caption broadcasting
8 TXT To toggle on/off the teletext mode
9 TV/AV To select an external input for the TV screen
10 TURBO SOUND To start turbo sound
11 TURBO PICTURE To start turbo picture
12 IN-START

13 ADJ To enter into the adjustment mode. To adjust horizontal line and sub-brightness.
14 MPX To select the multiple sound mode (Mono, Stereo or Foreign language).
15 EXIT To release the adjustment mode.
16 APC(PSM) To easily adjust the screen according to surrounding brightness.
17 ASC(SSM) To easily adjust sound according to the program type.
18 MULTIMIDIA To check component input.
19 FRONT-AV To check the front AV.
20 CH To move channel up/dow n or to select a function displayed on the screen.
21 VOL To adjust the volume or accurately control a specific function.
22 ENTER To set a specific function or complete setting.
23 PIP CH-(OP1) To move the channel dow n in the PIP screen. To use as a red key in the teletext mode.
24 PIP CH+(OP2) To move the channel in the PIP screen. To use as a green key in the teletext mode.
25 PIP SWAP(OP3) To switch between the main and sub screens. To use as a yellow key in the teletext mode.
26 PIP INPUT(OP4) To select the input status in the PIP screen. To use as a blue key in the teletext mode.
27 EYE To set a function that will automatically adjust screen status to match. The surrounding brightness so

28 MEN U To select the functions such as video, voice, function or channel.
29 I N-STOP To set the delivery condition status after man ufacturing the TV set.
30 STILL To halt the main screen in the normal mode, or the sub screen at the PIP screen. Used as a hold key in the

31 TIME Displays the teletext time in the normal mode. Enables to select the sub code in the teletext mod e .
32 SIZE Used as the size key in the PIP screen in the norm al mode. Used as the size key in the teletext mode.
33 MULTI PIP Used as the index key in the teletext mode. Top index w ill be displayed if it is the top text.
34 POSITION To select the position of the PIP screen in the normal mode. Used as the update key in the teletext mode

35 MODE Used as Mode in the teletext mode.
36 PIP To select the simultaneous screen.
37 TILT To adjust screen tilt.
38 0~9 To manually select the channel.

To enter adjustment mode w hen manufacturing the TV sets.

To adjust the screen voltage (automatic): In-start mute Adjust AV (Enter into W/B adjustment mode).

W/B adjustment (automatic): After adjusting the screen W/B adjustment Exit tw o times

natural color can be displayed.

teletext m ode. Page updating is stopped.

(Text w ill be displayed if the current page is updated.)

Directview LCD Training 9 Overview

- 10 -

THEORY

C

THEORY

This section covers how an LCD Display works.

LIQUID CRYSTAL DISPLAY

A Liquid Crystal Display is composed of a light source
(backlight), a Liquid Crystal Panel, and a driving circuit. We
start with a light source at the back of the panel composed
of thin fluorescent bulbs (CCFLs - Cold Cathode Flouresent
Lamps). This light passes through filters to help create a
uniform light source. Then the light passes through the Liquid
Crystal Panel which is composed of thousands of pixels that
control the flow of light throught the panel to make images.

Data Driver I

Driving

Circuit

Power Supply

for Video Signal

Printed Circuit Board

Gate Driver IC

Inverter

Pixel Array & Wiring

Back Light

Polarizer
CF Panel
Liquid Crystal
TFT Panel
Polarizer

Polarizer

TFT & Electrode

Liquid Crystals

Liquid Crystal

Color Filters

Polarizer

Top Electrode

Panel

An LCD panel from a 15" LCD TV.

Reflector

Light Guide

Frame

Diffusers

Lamp
Prism

Diffuser
Light Guide

Reflector
Inverter

Prism

Liquid Crystal Panel

Backlight Unit

Directview LCD Training 11 Theory

THEORY

LIQUID CRYSTAL PANEL

Below (on the left) is a cross section of a liquid crystal panel. The key to an LCD's operation is the
polarizers. The polarizers only allow a certain wavelength of light to pass through. The two polarizers
are mounted at a 90 degree angle with respect to each other, which prevents light from passing
through. The liquid crystals are used to twist the light beam 90 degrees and allow light to pass
through that cell. Color comes from a simple light filter.

TFT Element

Polari zer

Color Filter

Tra n s i s t o r

Gate Line

Data Line

Pixel Electrode

Common Electrode

Liquid Crystal

Polari zer

Each sub-pixel or cell (a red, green, and blue sub-pixel equals one
pixel) is controlled by a Thin Film Transistor (TFT). This provides
accurate control of each cell and makes for an accurate picture.
Some methods used in the past that didn't involve a switch and
current could leak to surrounding cells resulting in a blurred image.
A TFT is a semiconductor (bottom-right picture), it behaves like a
relay switch.

Pixel Electrode

(Transparent)

Source

Semi-conductor

Insulator

Gate

Glass Panel

Drain

Directview LCD Training 12 Theory

CIRCUIT DESCRIPTIONS

POWER SUPPLY

BLOCK DIAGRAM

19VDC Detect

CIRCUIT DESCRIPTIONS

6VDC

6VDC Detect

19VDC

24VDC

D212

D214, D215, D216

Main DC/DC

GND

Output

Rectifier

T101

24VDC Detect

PC104

U106

PWM

Controller

12VDC

D211

U203,

DC/DC

D212

Main DC/DC

Q202,

Q203

Output

Rectifier

T102

GND

PC105

PWM

12VDC Detect

U102

Controller

PFC Stage

Q602, Q603

Q600, Q601,

BD100

Bridge

RMI Filter

LP100, LT101

SC100

A/C Input

Directview LCD Training 13 Circuit Descriptions

U600

PFC Controler

D113 Run

PC102

Relay ON

GND

Tuner PCB

5VSB to Digital,

Output

Rectifier

T100

DC

Q500

Stand-by DC/

Rect.

Stand-by

D114, D115

3.4 Vo

U202,

DC/DC

PC103

Q200,

Q201

PWM

RLY On

U500

Controller

A/C Detect

DPM On/Off

24VDC Detect

Board

Micom

PC101

U510

A/C Detect

6VDC Detect

12VDC Detect

19VDC Detect

CIRCUIT DESCRIPTIONS

POWER SUPPLY SPECS

Output Voltage

Voltage Range

[V]

Current Range [A]

Output Voltage

Ripple Voltage Range [mVp-p]

Output Voltage

Static Regulation

Cross

Regulation

Load Max [A]

Voltage Spec [V] 4.95 ~ 5.45 3.2 ~ 3.6 5.7 ~ 6.3 11 ~ 13 16 ~ 20 22.8 ~ 25.2

Load Variable[A] 0.8 4 3.5 2.5 1 ~ 2.5 10.5

Voltage Spec [V] 4.95 ~ 5.45 3.2 ~3.6 5.7 ~6.3 11.4 ~ 12.6 16 ~ 20 22.8 ~ 25.2

No Load [A]

Voltage Spec [V]

STB 5Vo 3.4V 6Vo 12Vo 19Vo 24Vo

4.95 3.2 5.7 11.4 17

~ 5.45 ~ 3.6 ~ 6.3 ~ 12.6 ~ 20 ~ 25.2

2 5 5 3 4.4

STB 5Vo STB 3.4Vo 6Vo 12Vo 19Vo 24Vo

200mV 150mV 200mV 360mV 540mV 720mV

Output Regulation

STB 5Vo 3.4Vo 6Vo 12Vo 19Vo 24Vo

2 5 5 3 3

0.08 On / Off

4.95 ~ 5.45 3.2 ~3.6/OFF

Max Output

Max Ripple

Off

Off

22.8

12

10.5

Output Voltage

Load [A]

Wattage [W]

NO

1

2

3

4

5

6

Output Voltage

Name

STB5Vo

6Vo

12Vo

19Vo

24Vo

3.4Vo

Deep Sleep Mode

STB 5Vo 3.3Vo 12Vo 19Vo 24Vo 5Vo

0.08

Less than 1W [at 230Vac/50Hz]

0

SMPS Protect modes

*1)

Over Current Protection Over Voltage Protection

Range[A] Protection Range[V] Protection

Min. 3A Shutdown

Min. 6A Shutdown

Min. 4A Shutdown 14 Shutdown

Min. 5.5A Shutdown 22 Shutdown

Min. 14A Shutdown 26 Shutdown

Min. 6A Shutdown 4.5 Shutdown

8 Shutdown

Short circuit Protection

No Hardware

Failure

Directview LCD Training 14 Circuit Descriptions

VIDEO

CIRCUIT DESCRIPTIONS

VIDEO FLOWCHART

RF/Composite

C
o

m

p
o
n
e
n
t

/
H
D
M

I

OSD

Digital TV

CIRCUIT DESCRIPTION

The ATSC/NTSC tuner can receive both terrestrial analog and terrestrial digital signals. But the NTSC
tuner can receive terrestrial analog only. Therefore if you run two displays at The same time, it is
not possible to see two digital channels.

A/V SW (CXA2069) is the IC that takes external input terminal signals and broadcast signals from
the tuners and handles them selectively. Audio signals are sent to MSP4450. Video signals are sent
to HD-II via two paths - uPD64015 on the upper side is used to handle sub displays, while
uPD64015 on the lower side controls the main display.

To the lower side, signals are sent using an expensive 3D-comb filter with Y/C divided. The video
decoder (uPD64015) is a chip that decodes input signals. HD-II is a chip that controls nearly all
video-related functions, including brightness, sharpness, video formatting and scaling. If digital
broadcasting is available, it comes through Transport Stream, which can be controlled from HD-II.
Video SW (CXA2181) is an IC that outputs video signals selectively. The selected one is outputted
through MSP (MSP4450) as a digital signal.

Directview LCD Training 15 Circuit Descriptions