Text preview for : LG_2006_Training_Guide_[SM].pdf part of LG LG 2006 Training Guide [SM] LG Monitor LG_2006_Training_Guide_[SM].pdf



Back to : LG_2006_Training_Guide_[S | Home

TRAINING MANUAL


LCD DIRECTVIEW TELEVISION - 2006




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 1M and 5.2M. 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" compo-
nents. 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: 1-800-243-0000
TABLE OF CONTENTS
OVERVIEW .................................................. 5 TV GUIDE ................................................. 82
INTRODUCTION ........................................ 5 OVERVIEW ............................................ 82
MOUNTING INTERFACE .............................. 5 OPERATION ........................................... 82
COMPUTER CONNECTION ............................ 6 SYSTEM INFO ........................................ 83
REMOTES ................................................ 6 SYSTEM FLOWCHART ............................... 85
TERMINOLOGY ............................................ 7
VIEWING ANGLE ....................................... 7
IPS (IN-PLANE SWITCHING) ....................... 7
PEAK BRIGHTNESS ................................... 7
CONTRAST RATIO ...................................... 7
RESPONSE TIME ....................................... 7
A/V CONNECTIONS .................................... 8
THEORY ..................................................... 9
LIQUID CRYSTALS ..................................... 9
LIQUID CRYSTAL DISPLAY .......................... 9
LIQUID CRYSTAL PANEL ........................... 10
LCD VERSUS CRT .................................... 11
LCD VERSUS PLASMA .............................. 11
MODEL OVERVIEW ..................................... 12
MODEL NUMBERS ................................... 12
MODEL DESCRIPTIONS ............................. 15
CIRCUIT DESCRIPTIONS ............................. 20
15"CIRCUIT DESCRIPTIONS (L15V26) ........ 20
30"CIRCUIT DESCRIPTIONS (L30W26) ....... 23
32" CIRCUIT DESCRIPTIONS (CABLECARD MODELS)
28
FIRMWARE UPDATES .................................. 33
FIRMWARE UPDATES VIA MEMORY CARD ..... 33
DISASSEMBLY ........................................... 37
SMALL SCREEN MODELS ........................... 37
LARGE SCREEN MODELS - PART 1 .............. 37
LARGE SCREEN MODELS - PART 2 .............. 39
EXPLODED VIEWS ................................... 40
CABLECARD .............................................. 62
DIGITAL CABLE READY (DCR) .................... 62
CEA-NCTA AGREEMENT ............................. 62
TERMS ................................................. 63
VENDORS .............................................. 63
DCR ARCHITECTURE ................................ 64
HOST-CABLECARD INTERFACE ................... 64
IN-BAND/OOB SPECIFICATION ................... 66
CABLE MENU & MMI ............................... 67
DIGITAL CERTIFICATES DATA ..................... 70
CABLECARD RESET .................................. 70
EAS (EMERGENCY ALERT SYSTEM) .............. 70
HOST DIAGNOSTICS ................................ 71
ERROR REPORTING ................................. 71
CABLE CARD TROUBLESHOOTING ............... 72
IN-HOME TROUBLESHOOTING ................... 77
CABLECARD TROUBLESHOOTING ................ 80




Directview LCD Training 3 Contents
-4-
OVERVIEW

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. For service, the end user
should call 1-800-243-0000 for complete shipping and handling
instructions. 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. Although, warranty repair by an
ASC is approved in certain situations for smaller screen models. Contact
the LG Warranty department for more information.
Most models are similiar in function and internal layout with the exception of models over 23". For
example, the 30" inch LCD has more fluorescent lamps than normal (16 lamps) and some additional
user functions.
Note that not all models support HDTV (High Definiton Television). The 10", 13", and 20" models do
not support HDTV, but 20" models do support EDTV (Enhanced Definiton Television). The section on
Models has more information about the specifications of each model.

MOUNTING INTERFACE
The Video Electronics Standards Association (VESA) Flat Display Mounting Interface Standard (FDMI)
outlines mounting interface standards for flat-panel displays. VESA FDMI Standards are 75 x 75 mm,
100 x 100 mm, and 100 x 200 mm mounting hole pattern with 4, 4 mm x 10 mm screws. Most new
models feature a VESA mount, except large screen models. Large screen models use mounting hole
patterns similar to PDPs.



75MM MOUNT
10" Models
100mm
100MM MOUNT 4mm
13" to 23"
100mm
10mm
200MM MOUNT
26" to 32" Models

NO VESA MOUNT
37, 42, & 55" models




Directview LCD Training 5 Overview
OVERVIEW
COMPUTER CONNECTION Computer Video Modes

Most models except the 10", 13", and 20" support Horizontal Vertical
Mode Resolution
Frequency (KHz) Frequency (KHz)
computer video. Set the monitor output resolution
VGA 640x400 31.5KHz 70Hz
and vertical frequency on the PC before connecting
640x400 37.9KHz 85Hz
to the TV (see table). Connect the TV to the computer 640x480 31.5KHz 60Hz
with a VGA cable. Connect the computer's audio 640x480 35.0KHz 67Hz
output to the TV's PC SOUND input. 640x480 37.9KHz 72Hz
The TV has been pre-adjusted to use XGA 1024x768, 640x480 37.5KHz 75Hz
640x480 43.3KHz 85Hz
60Hz format. If possible, use one of the XGA formats
720x400 31.5KHz 70Hz
to obtain the best image quality for your TV/LCD SVGA 800x600 35.2KHz 56Hz
monitor. LCD monitors should be used at their native 800x600 37.9KHz 60Hz
(normally their max) resolution. If set up under 800x600 48.1KHz 72Hz
other resolutions, a slightly distorted picture may 800x600 46.9KHz 75Hz
appear on the screen. If the message "OUT OF 800x600 53.7KHz 85Hz
RANGE" appears on the screen, adjust the PC output (MAC) 832x624 49.7KHz 75Hz
XGA 1024x768 48.4KHz 60Hz
to a format listed in the chart.
1024x768 56.5KHz 70Hz
1024x768 60.2KHz 75Hz
1024x768 68.67KHz 85Hz




REMOTES
2001/2002 2003+ 2005+
30" LCD STYLE
SMALL SCREEN MODELS SMALL SCREEN MODELS REMOTE LARGE SCREEN MODELS
POWER


SLEEP INPUT SELECT
mute power
APC DASP

power tv/video ARC PIP ARC
tv/video multimedia mts
PIP TWIN PICTURE
fcr exit menu
1 2 3 SWAP SUB INPUT

MENU MUTE
4 5 6
ch
7 8 9 ENTER
VOL VOL
flashbk cc enter
vol vol
0 ch
menu mute


ch 1
1 2
2 3
vol enter vol 1 2 3
4
4 5
5 6
4 5 6
mts ch sleep
7
7 8
8 9
9 7 8 9
audio video
0
0
pip position
cc flashbk sleep
pip input ch
pip position


pip input ch
WIN.SIZE WIN.POSITION

ZOOM- ZOOM+




Directview LCD Training 6 Overview
TERMINOLOGY

TERMINOLOGY
This section explains some of the terminology used with LCD TVs.
VIEWING ANGLE
Viewing angle is the angle at which the display's brightness begins to noticeably diminish. Viewing
angle used to be a major factor when choosing an LCD but they have improved enough on current
models that it is not an issue anymore. This is due to advancements like In-Plane Switching, High-
efficiency Backlights, and reflective Polarizers. Some smaller screen LCDs (under 15") may still have
limited viewing angles to keep costs down.
IPS (IN-PLANE SWITCHING) Liquid Crystal

In-Plane Switching provides more control over the
Electrode
Liquid Crystals in an LCD. It uses an electric field to
line up the Liquid Crystals in an arc formation. This
directs light out at angles which improves the viewing Conventional TFT-LCD IPS Mode TFT-LCD
angle.
PEAK BRIGHTNESS
Peak brightness is the maximum amount of brightness that a display can produce. It is often measured
in candella per square meter (cd/m2). Most
LG and Zenith LCDs are 400-450 cd/m2.


CONTRAST RATIO
Contrast Ratio is the ratio of a display's
brightest white to its darkest black. Higher
Contrast Ratios are better and will allow a
TV to reproduce a more realistic picture
and make text easier to read. One of the
limitations of LCDs has been contrast ratio.
With recent improvements, our LCD TVs have a contrast ratio up to 450:1.


RESPONSE TIME
The speed at which the pixels can react or change. Slower response times can cause fast moving video
to "ghost" or distort because the scene changes faster than the LCD can display the video (especially
with video games). Response times of new LCDs isn't a factor for most uses, but older models could
experience noticable ghosting due to slower response times.




Directview LCD Training 7 Terminology
TERMINOLOGY
A/V CONNECTIONS
Below are connections you may find on LCD TVs. SD = Standard Definition and HD = High Definition.

Composite P
R

Normally labeled "Composite" and/or Component Video
"Video". SD Only.
P
B Normally labeled "Component/
DTV/DVD". Supports HD.
Y
S-Video
Super Video. Normally labeled "S-Video". SD Digital Audio
Only. A little better quality than Composite. Normally labeled "Digital Audio (coaxial)".
Better quality then normal audio. Supports
Antenna
Surround Sound.
Normally labeled "Antenna".
Supports HD. A.k.a. Coax, Cable. Optical Audio
VGA Normally labeled "Digital Audio (optical)".
Normally labeled "RGB" and/or Better quality then normal audio. Supports
"PC/DTV". Supports HD. Surround Sound. Uses a fiber optic cable.
DVI RS-232
Normally labeled "DVI", "PC/DTV", or "HDMI". Normally labeled "Calibration Port", "Service
Digital instead of analog (Digital version of Port", and/or "RS-232". A.k.a. serial port.
VGA). Supports HD. Used for uploading firmware or external
control of the unit (no video or audio).
HDMI
IEEE 1394
Normally labeled "HDMI". Newer version
of DVI. Supports HD and Digital Audio. Normally labeled "IEEE 1394" or "DTV Link".
Supports HD and Digital Audio.




Directview LCD Training 8 Terminology
THEORY

THEORY
This section covers what Liquid Crystals are and how an LCD Display works.
LIQUID CRYSTALS
In school you learned that matter has three distinct states; solid, liquid, and gas. However, there are
states of matter that may fall between these states, like liquid crystals. Basically they are crystals
that hold their orientation (shape) but can flow similar to liquids. Their molecules point in same
direction with respect to each other like in a solid, but they are free to change position like in a
liquid. Think of a handful of pencils. They collectively hold their shape at rest, but change shape when
you squeeze or let go of them.




SOLID LIQUID LIQUID CRYSTAL


There are different phases and types of liquid crystals that perform differently. Small amounts of
pressure, heat, and/or electricity can cause liquid crystals to change in some way. For LCDs we are
interested in the electricity aspect, but pressure and heat are side effects that have to be dealt with.
This is why LCDs have a limited operating range and distort when you press on the screen.
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 IC
Printed Circuit Board
Driving
Circuit Gate Driver IC
Inverter

Pixel Array & Wiring

Power Supply Polarizer
for Video Signal CF Panel
Liquid Crystal Liquid Crystal
Panel
TFT Panel
Polarizer

Lamp
Prism
Diffuser Backlight Unit
Light Guide
Reflector
Inverter



Directview LCD Training 9 Theory
THEORY
An LCD panel from a 15" LCD TV.



Reflector
Light Guide
Frame
Diffusers
Prism
Liquid Crystal Panel




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
Polarizer

Color Filter
Pixel Electrode
Transistor (Transparent)
Common Electrode
Gate Line
Data Line
Liquid Crystal
Pixel Electrode
Polarizer
Source Gate Drain
Semi-conductor
Insulator
Glass Panel



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.


Directview LCD Training 10 Theory
THEORY

LCD VERSUS CRT
One disatvantage LCDs have is having fixed
pixels which makes it more difficult to scale
video than a CRT. A CRT can change the pixel
size by adjusting the size of the beam, LCDs
use a processor called a Scalar. LCDs feature
their best picture quality at their native
resolution (or max res) and CRTs feature good Scaled
video
quality at any resolution up to their maximum
example
resolution.




LCD ADVANTAGES OVER CRT CRT ADVANTAGES OVER
Uses less power LCD
Less heat ouput Better scaling
Smaller and lighter Less expensive
Unaffected by Magnetic Fields


LCD VERSUS PLASMA




LCD ADVANTAGES OVER PLASMA PLASMA ADVANTAGES OVER LCD
Uses less power Less expensive (for same screen size)
Smaller and lighter Brighter
Replaceable backlight Better contrast




Directview LCD Training 11 Theory
- 12 -
MODELS

MODEL OVERVIEW
This section covers some of the past and present LG and Zenith LCD TVs. Most LCD TVs feature similar
features and specifications. They support High Definition and computer input, except for the 10",
13", 20", and the wireless 15" models. The 2005 models 26" and larger have built-in ATSC tuners and
support CableCARDTM. Note that Commerical models don't have CableCARDTM support since it is not
needed in a distribution network.
KEY TERMS
SDTV - Standard Definition (480i).
EDTV - Enhanced Definition (480p).
HDTV - High Definition (720p, 1080i).
XD EngineTM - Six distinct processes contribute to picture improvement.
CableCARDTM - Decoder card for digital cable.
HDMI - High Definition Multimedia Interface. Alternative to DVI. Smaller connector and
supports audio.
HDCP - High-bandwidth Digital Content Protection.

MODEL NUMBERS
OLDER ZENITH PRODUCTS (02-04)

Old Zenith Structure: L15V26

Display Type Screen Size Aspect Ratio Model Year Feature Level
L = LCD V= 4:3 2 = 2002 2 = Consumer
P = Plasma W = 16:9 3 = 2003 4 = Commercial
R = CRT 4 = 2004 6 = Consumer
Rear Projo
D = Micro
Display




Directview LCD Training 13 Models
MODELS
OLDER LG PRODUCTS

Old LG Structure: MU