Text preview for : LG_L30W36_2_[SM].pdf part of LG LG L30W36 2 [SM] LG Monitor LG_L30W36_2_[SM].pdf
Back to : LG_L30W36_2_[SM].pdf | Home
SERVICE MANUAL
Model Series:
Product Type: LCD Directview
L30W36
Chassis: MF02HA
Manual Series: PV155
Model Line: F
Product Year: 2003
REVISED EDITION
Training material added
CONTENTS
OVERVIEW ............................................ 5
THEORY ............................................... 7
CIRCUIT DESCRIPTIONS .......................... 13
DISASSEMBLY ...................................... 23
ADJUSTMENTS ..................................... 25
DIAGRAMS .......................................... 28
PARTS ................................................ 35
Published June 2003
by Technical Publications
Zenith Electronics Corporation
201 James Record Road
Huntsville, Alabama 35824-1513
Copyright 2003 by Zenith Electronics Corporation
Printed in U.S.A.
PRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO-VIDEO PRODUCTS
IMPORTANT SAFETY NOTICE 5. Caution customers against mounting a product on a sloping shelf or in a
This manual was prepared for use only by properly trained audio-video service tilted position, unless the receiver is properly secured.
technicians.
6. A product on a roll-about cart should be stable in its mounting to the cart.
When servicing this product, under no circumstances should the original Caution the customer on the hazards of trying to roll a cart with small
design be modified or altered without permission from Zenith Electronics casters across thresholds or deep pile carpets.
Corporation. All components should be replaced only with types identical to
those in the original circuit and their physical location, wiring and lead dress 7. Caution customers against using a cart or stand that has not been listed by
must conform to original layout upon completion of repairs. Underwriters Laboratories, Inc. for use with its specific model of television
receiver or generically approved for use with TVs of the same or larger screen
Special components are also used to prevent shock and fire hazard. These size.
components are indicated by the letter "x" included in their component
designators and are required to maintain safe performance. No deviations are 8. Caution customers against using extension cords. Explain that a forest of
allowed without prior approval by Zenith Electronics Corporation. extensions, sprouting from a single outlet, can lead to disastrous
consequences to home and family.
Circuit diagrams may occasionally differ from the actual circuit used. This way,
implementation of the latest safety and performance improvement changes into ELECTROSTATICALLY SENSITIVE DEVICES
the set is not delayed until the new service literature is printed. Some semiconductor (solid-state) devices can be damaged easily by static elec-
tricity. Such components commonly are called Electrostatically Sensitive (ES)
CAUTION: Do not attempt to modify this product in any way. Never perform Devices. Examples of typical ES devices are integrated circuits and some field-
customized installations without manufacturer's approval. Unauthorized effect transistors and semiconductor "chip" components. The following tech-
modifications will not only void the warranty, but may lead to property damage niques should be used to help reduce the incidence of component damage
or user injury. Service work should be performed only after you are thoroughly caused by static electricity.
familiar with these safety checks and servicing guidelines.
1. Immediately before handling any semiconductor component or semiconduc-
FIRE AND SHOCK HAZARD tor-equipped assembly, drain off any electrostatic charge on the body by touch-
While servicing, use an isolation transformer for protection from AC line shock. ing a known earth ground. Alternatively, obtain and wear a commercially available
After the original service problem has been corrected, make a check of the discharging wrist strap device, which should be removed for potential shock
following. reasons prior to applying power to the unit under test.
1. Be sure that all components are positioned to avoid a possibility of 2. After removing an electrical assembly equipped with ES devices, place the
adjacent component shorts. This is especially important on items trans- assembly on a conductive surface such as an ESD mat, to prevent electrostatic
ported to and from the repair shop. charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
2. Verify that all protective devices such as insulators, barriers, covers,
shields, strain reliefs, power supply cords, and other hardware have been 4. Use only an anti-static solder removal device. Some solder removal devices not
reinstalled per the original design. Be sure that the safety purpose of the classified as "anti-static" can generate electrical charges sufficient to damage ES
polarized line plug has not been defeated. devices.
3. Soldering must be inspected to discover possible cold solder joints, 5. Do not use freon-propelled chemicals. These can generate electrical charge
solder splashes, or sharp solder points. Be certain to remove all loose sufficient to damage ES devices.
foreign particles. 6. Do not remove a replacement ES device from its protective package until
4. Check for physical evidence of damage or deterioration to parts and immediately before you are ready to install it. (Most replacement ES devices are
components, for frayed leads or damaged insulation (including the AC packaged with leads electrically shorted together by conductive foam, aluminum
cord), and replace if necessary. foil, or comparable conductive material.)
7. Immediately before removing the protective material from the leads of a
5. No lead or component should touch a high current device or a resistor
replacement ES device, touch the protective material to the chassis or circuit
rated at 1 watt or more. Lead tension around protruding metal surfaces
assembly into which the device will be installed.
must be avoided.
Caution: Be sure no power is applied to the chassis or circuit, and observe all
6. After reassembly of the set, always perform an AC leakage test on all other safety precautions.
exposed metallic parts of the cabinet (the channel selector knobs, antenna
terminals, handle and screws) to be sure that set is safe to operate 8. Minimize bodily motions when handling unpackaged replacement ES devices.
without danger of electrical shock. DO NOT USE A LINE ISOLATION TRANS- (Otherwise, seemingly harmless motion, such as the brushing together of your
FORMER DURING THIS TEST. Use an AC voltmeter having 5000 ohms per volt clothing or the lifting of your foot from a carpeted floor, can generate static
or more sensitivity in the following manner: Connect a 1500 ohm, 10 watt electricity sufficient to damage an ES device.)
resistor, paralleled by a .15 mfd 150V AC type capacitor between a known
REGULATORY INFORMATION
good earth ground water pipe, conduit, etc.) and the exposed metallic
parts, one at a time. Measure the AC voltage across the combination of This equipment has been tested and found to comply with the limits
1500 ohm resistor and .15 mfd capacitor. Reverse the AC plug by using a for a Class B digital device, pursuant to Part 15 of the FCC Rules.
non-polarized adaptor and repeat AC voltage measurements for each ex- These limits are designed to provide reasonable protection against
posed metallic part. Voltage measured must not exceed 0.75 volts RMS. harmful interference when the equipment is operated in a residential
This corresponds to 0.5 milliamp AC. Any value exceeding this limit installation. This equipment generates, uses and can radiate radio
constitutes a potential shock hazard and must be corrected immediately. frequency energy and, if not installed and used in accordance with
the instruction manual, may cause harmful interference to radio
TIPS ON PROPER INSTALLATION communications. However, there is no guarantee that interference
1. Never install any receiver in a closed-in recess, cubbyhole, or closely
fitting shelf space over, or close to, a heat duct, or in the path of heated
will not occur in a particular installation. If this equipment does
air flow. cause harmful interference to radio or television reception, which
can be determined by turning the equipment off and on, the user is
2. Avoid conditions of high humidity such as: outdoor patio installations
where dew is a factor, near steam radiators where steam leakage is a factor, encouraged to try to correct the interference by one or more of the
etc. following measures: Reorient or relocate the receiving antenna; In-
3. Avoid placement where draperies may obstruct venting. The customer
crease the separation between the equipment and receiver; Connect
should also avoid the use of decorative scarves or other coverings that the equipment into an outlet on a circuit different from that to
might obstruct ventilation. which the receiver is connected; Consult the dealer or an experi-
4. Wall- and shelf-mounted installations using a commercial mounting kit enced radio/TV technician for help.
must follow the factory-approved mounting instructions. A product mounted The responsible party for this device's compliance is:
to a shelf or platform must retain its original feet (or the equivalent Zenith Electronics Corporation
thickness in spacers) to provide adequate air flow across the bottom. Bolts 201 James Record Road
or screws used for fasteners must not touch any parts or wiring. Perform
leakage tests on customized installations.
Huntsville, AL 35824, USA
Digital TV Hotline: 1-800-243-0000
L30W36 i SAFETY
TABLE OF CONTENTS
OVERVIEW ............................................ 5
INTRODUCTION ............................................... 5
SPECIFICATIONS ............................................. 6
EXTERNAL CONTROL ............................... 7
CONNECTION .................................................. 7
CONFIGURATIONS ........................................... 7
TRANSMISSION PROTOCOL ................................ 8
LCD DISPLAY ................................................ 12
THEORY .............................................. 12
LIQUID CRYSTALS ......................................... 12
LCD PANEL .................................................. 13
TERMINOLOGY .............................................. 14
CIRCUIT DESCRIPTIONS .......................... 16
SYSTEM OVERVIEW ........................................ 16
POWER SUPPLY ............................................ 16
VIDEO ........................................................ 20
AUDIO ........................................................ 21
DISASSEMBLY ...................................... 22
ADJUSTMENT INSTRUCTIONS ................... 24
NOTES ........................................................ 24
HEAT-RUN MODE .......................................... 24
EDID ADJUSTMENT ........................................ 24
WHITE BALANCE ADJUSTMENT ......................... 25
DIAGRAMS .......................................... 26
EXPLODED VIEW ........................................... 26
PCB DIAGRAMS ............................................ 28
PARTS ................................................ 33
POWER SUPPLY CIRCUIT ................................ 39
SCHEMATICS ........................................ 40
MAIN CIRCUIT ............................................. 40
DIGITAL CIRCUIT .......................................... 41
MICROPROCESSOR CIRCUIT ............................. 42
DIGITAL MICROPROCESSOR CIRCUIT ................. 43
DECODER CIRCUIT ......................................... 44
DRIVER CIRCUIT 1/3 .................................... 45
LCD DRIVER CIRCUIT 2/3 ............................... 46
LCD DRIVER CIRCUIT 3/3 ............................... 47
D60WLCD - 923-03486 TOC
OVERVIEW
OVERVIEW
INTRODUCTION
This manual covers the 30" LG and Zenith LCDs. They feature a 30" viewable area in a widescreen
format. They do not have a built in tuner but do have two RGB inputs, one VGA and one DVI-I. The
"-I" of "DVI-I" means they support both digital and analog, so a regular VGA connection can be
input to this connection using a DVI to VGA adapter (not supplied). The reason for two adapters is to
allow a computer and a set-top box to be connected at the same time. It is recommended to connect
devices like a computer using the DVI connection due to the high resolution and to avoid any
interference. This model also features regular TV connections to allow other components such as VCRs
and DVDs to be connected.
The internal layout is slightly different than smaller LCD TVs. This LCD has more fluorescent lamps
(16) and a built-in power supply that earlier smaller models didn't have. This model features a service
menu with advanced settings that can be accessed using an NEC service remote. Some new functions
are available to the operator. These include; Color Temperature, Screen Saver, Picture Format, Zoom,
Picture Position, and a VCR jitter removal feature.
This LCD is module level repair only. This device is more delicate than a regular TV and extra care
should be taken when working on it. The screen is plastic instead of glass and it's circuits are static
sensitive. Most failures will be related to a lamp inverter or a lamp, which will likely be reported by
the consumer as the screen suddenly becoming darker or flickering. There are four lamp assemblies
per inverter (2 lamps per assembly), so if an inverter is defective it will affect four lamp assemblies at
once (half the screen) versus a lamp related problem that will affect only one lamp at a time.
L30W36 5 OVERVIEW
OVERVIEW
SPECIFICATIONS
DISPLAY
Screen: 30" (30"VIS) WXGA Active Matrix TFT Color LCD, Digital Progressive 25.3" x 15.2"
(643mm x 386mm)
Aspect Ratio: 16:9
Pixel Clock: 65Mhz
Contrast Ratio: 450:1
Response Time: 22ms (Typical), 25ms (Max.)
Peak Brightness: 450 cd/m2
Fall & Rise Time: 12ms (Typical)
Native Display Resolution: 1280 x 768 (WXGA)
Cell Pitch (HxV): 0.5025mm x 0.1675mm x RGB
Backlighting: 16 CCFL Lamps Hf: 31.5~80KHz Vf: 56~120Hz
Displayable Colors: 16.77 Million (24 Bit)
Surface Treatment: Hard Coating 3H, Anti-Glare
Viewing Angle: 170