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Internal Use Only
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LCD TV SERVICE MANUAL
CHASSIS : LA75E

MODEL : 19LC2D
CAUTION

19LC2D-UB

BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CONTENTS

CONTENTS .............................................................................................. 2 SAFETY PRECAUTIONS ..........................................................................3 SPECIFICATION ........................................................................................6 ADJUSTMENT INSTRUCTION .................................................................8 TROUBLE SHOOTING ............................................................................12 BLOCK DIAGRAM...................................................................................16 EXPLODED VIEW .................................................................................. 18 SVC. SHEET ...............................................................................................

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

SAFETY PRECAUTIONS
IMPORTANT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the Schematic Diagram and Replacement Parts List. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer.

General Guidance
An isolation 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 as this protects the technician from accidents resulting in personal injury from electrical shocks. It will also protect the receiver and it's components from being damaged by accidental shorts of the circuitry that may be inadvertently introduced during the service operation. If any fuse (or Fusible Resistor) in this TV receiver is blown, replace it with the specified. When replacing a high wattage resistor (Oxide Metal Film Resistor, over 1W), keep the resistor 10mm away from PCB. Keep wires away from high voltage or high temperature parts.

Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet. Do not use a line Isolation Transformer during this check. Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth ground (Water Pipe, Conduit, etc.) and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more sensitivity. Reverse plug the AC cord into the AC outlet and repeat AC voltage measurements for each exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which is corresponds to 0.5mA. In case any measurement is out of the limits specified, there is possibility of shock hazard and the set must be checked and repaired before it is returned to the customer.

Leakage Current Hot Check circuit

AC Volt-meter
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.

Leakage Current Cold Check(Antenna Cold Check)
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. An other abnormality exists that must be corrected before the receiver is returned to the customer.

To Instrument's exposed METALLIC PARTS

0.15uF

Good Earth Ground such as WATER PIPE, CONDUIT etc.

1.5 Kohm/10W

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

SERVICING PRECAUTIONS
CAUTION: Before servicing receivers covered by this service manual and its supplements and addenda, read and follow the SAFETY PRECAUTIONS on page 3 of this publication. NOTE: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions on page 3 of this publication, always follow the safety precautions. Remember: Safety First. General Servicing Precautions 1. Always unplug the receiver AC power cord from the AC power source before; a. Removing or reinstalling any component, circuit board module or any other receiver assembly. b. Disconnecting or reconnecting any receiver electrical plug or other electrical connection. c. Connecting a test substitute in parallel with an electrolytic capacitor in the receiver. CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard. 2. Test high voltage only by measuring it with an appropriate high voltage meter or other voltage measuring device (DVM, FETVOM, etc) equipped with a suitable high voltage probe. Do not test high voltage by "drawing an arc". 3. Do not spray chemicals on or near this receiver or any of its assemblies. 4. Unless specified otherwise in this service manual, clean electrical contacts only by applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or comparable non-abrasive applicator; 10% (by volume) Acetone and 90% (by volume) isopropyl alcohol (90%-99% strength) CAUTION: This is a flammable mixture. Unless specified otherwise in this service manual, lubrication of contacts in not required. 5. Do not defeat any plug/socket B+ voltage interlocks with which receivers covered by this service manual might be equipped. 6. Do not apply AC power to this instrument and/or any of its electrical assemblies unless all solid-state device heat sinks are correctly installed. 7. Always connect the test receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead. Always remove the test receiver ground lead last. 8. Use with this receiver only the test fixtures specified in this service manual. CAUTION: Do not connect the test fixture ground strap to any heat sink in this receiver. Electrostatically Sensitive (ES) 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 by static electricity. 1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed to prevent potential shock reasons prior to applying power to the
Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

unit under test. 2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3. Use only a grounded-tip soldering iron to solder or unsolder ES devices. 4. Use only an anti-static type solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient to damage ES devices. 5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices. 6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material). 7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed. CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions. 8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES device.) General Soldering Guidelines 1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that will maintain tip temperature within the range or 500F to 600F. 2. Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40 parts lead. 3. Keep the soldering iron tip clean and well tinned. 4. Thoroughly clean the surfaces to be soldered. Use a mall wirebristle (0.5 inch, or 1.25cm) brush with a metal handle. Do not use freon-propelled spray-on cleaners. 5. Use the following unsoldering technique a. Allow the soldering iron tip to reach normal temperature. (500F to 600F) b. Heat the component lead until the solder melts. c. Quickly draw the melted solder with an anti-static, suctiontype solder removal device or with solder braid. CAUTION: Work quickly to avoid overheating the circuit board printed foil. 6. Use the following soldering technique. a. Allow the soldering iron tip to reach a normal temperature (500F to 600F) b. First, hold the soldering iron tip and solder the strand against the component lead until the solder melts. c. Quickly move the soldering iron tip to the junction of the component lead and the printed circuit foil, and hold it there only until the solder flows onto and around both the component lead and the foil. CAUTION: Work quickly to avoid overheating the circuit board printed foil. d. Closely inspect the solder area and remove any excess or splashed solder with a small wire-bristle brush.

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LGE Internal Use Only

IC Remove/Replacement Some chassis circuit boards have slotted holes (oblong) through which the IC leads are inserted and then bent flat against the circuit foil. When holes are the slotted type, the following technique should be used to remove and replace the IC. When working with boards using the familiar round hole, use the standard technique as outlined in paragraphs 5 and 6 above. Removal 1. Desolder and straighten each IC lead in one operation by gently prying up on the lead with the soldering iron tip as the solder melts. 2. Draw away the melted solder with an anti-static suction-type solder removal device (or with solder braid) before removing the IC. Replacement 1. Carefully insert the replacement IC in the circuit board. 2. Carefully bend each IC lead against the circuit foil pad and solder it. 3. Clean the soldered areas with a small wire-bristle brush. (It is not necessary to reapply acrylic coating to the areas). "Small-Signal" Discrete Transistor Removal/Replacement 1. Remove the defective transistor by clipping its leads as close as possible to the component body. 2. Bend into a "U" shape the end of each of three leads remaining on the circuit board. 3. Bend into a "U" shape the replacement transistor leads. 4. Connect the replacement transistor leads to the corresponding leads extending from the circuit board and crimp the "U" with long nose pliers to insure metal to metal contact then solder each connection. Power Output, Transistor Device Removal/Replacement 1. Heat and remove all solder from around the transistor leads. 2. Remove the heat sink mounting screw (if so equipped). 3. Carefully remove the transistor from the heat sink of the circuit board. 4. Insert new transistor in the circuit board. 5. Solder each transistor lead, and clip off excess lead. 6. Replace heat sink. Diode Removal/Replacement 1. Remove defective diode by clipping its leads as close as possible to diode body. 2. Bend the two remaining leads perpendicular y to the circuit board. 3. Observing diode polarity, wrap each lead of the new diode around the corresponding lead on the circuit board. 4. Securely crimp each connection and solder it. 5. Inspect (on the circuit board copper side) the solder joints of the two "original" leads. If they are not shiny, reheat them and if necessary, apply additional solder. Fuse and Conventional Resistor Removal/Replacement 1. Clip each fuse or resistor lead at top of the circuit board hollow stake. 2. Securely crimp the leads of replacement component around notch at stake top. 3. Solder the connections. CAUTION: Maintain original spacing between the replaced component and adjacent components and the circuit board to prevent excessive component temperatures.
Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

Circuit Board Foil Repair Excessive heat applied to the copper foil of any printed circuit board will weaken the adhesive that bonds the foil to the circuit board causing the foil to separate from or "lift-off" the board. The following guidelines and procedures should be followed whenever this condition is encountered. At IC Connections To repair a defective copper pattern at IC connections use the following procedure to install a jumper wire on the copper pattern side of the circuit board. (Use this technique only on IC connections). 1. Carefully remove the damaged copper pattern with a sharp knife. (Remove only as much copper as absolutely necessary). 2. carefully scratch away the solder resist and acrylic coating (if used) from the end of the remaining copper pattern. 3. Bend a small "U" in one end of a small gauge jumper wire and carefully crimp it around the IC pin. Solder the IC connection. 4. Route the jumper wire along the path of the out-away copper pattern and let it overlap the previously scraped end of the good copper pattern. Solder the overlapped area and clip off any excess jumper wire. At Other Connections Use the following technique to repair the defective copper pattern at connections other than IC Pins. This technique involves the installation of a jumper wire on the component side of the circuit board. 1. Remove the defective copper pattern with a sharp knife. Remove at least 1/4 inch of copper, to ensure that a hazardous condition will not exist if the jumper wire opens. 2. Trace along the copper pattern from both sides of the pattern break and locate the nearest component that is directly connected to the affected copper pattern. 3. Connect insulated 20-gauge jumper wire from the lead of the nearest component on one side of the pattern break to the lead of the nearest component on the other side. Carefully crimp and solder the connections. CAUTION: Be sure the insulated jumper wire is dressed so the it does not touch components or sharp edges.

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LGE Internal Use Only

SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement.

1. Application range
This specification is applied all of the LCD TV with LA75E chassis.

3. Test method
(1) Performance : LGE TV test method followed (2) Demanded other specification Safety : UL, CSA, IEA Specification EMC : FCC, ICES, IEC Specification

2. Requirement for Test
Each part is tested as below without special appointment. (1) Temperature : 20 5C (2) Relative Humidity : 65 10% (3) Power voltage : Standard input voltage([email protected]/60Hz) *Standard Voltage of each products is marked by models. (4) Specification and performance of each parts are followed each drawing and specification by part number in accordance with BOM. (5) The receiver must be operated for about 30 minutes prior to the adjustment.

4. General Specification(TV)
No 1 2 Item Receivable System Available Channel VHF UHF DTV CATV 3 4 5 6 7 8 9 10 Input Voltage Market Screen size Aspect Ratio Tuning System LCD Module Operating Environment Storage Environment Specification ATSC/64 & 256 QAM/ NTSC-M : 02 ~ 13 : 14 ~ 69 : 02 ~ 69 : 01 ~ 135 Remark

CADTV : 01 ~ 135 100-240V~, 50/60Hz NORTH AMERICA 19 inch Wide 16 : 9 FS LM190WX1(1440*900) M190A1-L02(1440*900) Temp : 0 ~ 40 deg Humidity : 10~90 %RH Temp : -20 ~ 50 deg Humidity : 10~90 %RH Wide, LPL Wide, CHI MEI

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

5. Component Video Input (Y, PB, PR)
No 1 2 3 4 5 6 7 8 9 10 11 12 Resolution 720*480 720*480 720*480 720*480 1280*720 1280*720 1920*1080 1920*1080 1920*1080 1920*1080 1920*1080 1920*1080 H-freq(kHz) 15.73 15.75 31.47 31.50 44.96 45.00 33.72 33.75 27 33.75 67.43 67.5 V-freq.(kHz) 59.94 60.00 59.94 60.00 59.94 60.00 59.94 60.00 24 30 59.94 60 Pixel clock(MHz) Proposed SDTV, DVD 480I SDTV, DVD 480I SDTV 480P SDTV 480P HDTV 720P HDTV 720P HDTV 1080I HDTV 1080I HDTV 1080P HDTV 1080P HDTV 1080P HDTV 1080P

6. RGB Input (PC)
No PC 1 2 3 4 5 7 8 9 10 11 Resolution 640*350 720*400 640*480 800*600 1024*768 1280*768 1360*768 1366*768 1440*900 1680*1050 H-freq.(kHz) 31.469 31.469 31.469 37.879 48.363 47.776 47.712 60.023 55.5 62.290 V-freq.(kHz) 70.08 70.08 59.94 60.31 60.00 59.87 60.01 60.00 59.90 59.954 Pixel clock(MHz) 25.17 28.32 25.17 40.00 65.00 79.50 85.50 80.00 88.750 146.25 20/23LS7D only 19LS4D-UA only 22LS4D-UA only Remark DOS DOS VESA(VGA) VESA(SVGA) VESA(XGA) VESA(WXGA) VESA(WXGA) VESA(WXGA) WXGA WSXGA O O O O O O O Proposed DDC

7. HDMI/DVI input (PC)
No PC 1. 2. 3. 4. 5. 6. 7. 8. DTV 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. Resolution 640*480 800*600 1024*768 1280*768 1360*768 1366*768 1440*900 1680*1050 720*480 720*480 1280*720 1280*720 1920*1080 1920*1080 1920*1080 1920*1080 1920*1080 1920*1080 H-freq.(kHz) 31.469 37.879 48.363 47.776 47.720 47.13 55.5 62.290 31.469 31.500 44.96 45.00 33.72 33.75 27 33.75 67.43 67.5 V-freq.(kHz) 59.94 60.31 60.00 59.87 59.799 59.65 59.90 59.954 59.94 60.00 59.94 60.00 59.94 60.00 24.00 30.00 59.94 60.00 Pixel clock(MHz) 25.17 40.00 65.00 79.50 84.75 72 88.750 146.25 27.00 27.03 74.17 74.25 74.17 74.25 74.25 74.25 148.35 148.50 19LS4D-UA only 22LS4D-UA only Remark Proposed VESA(VGA) VESA(SVGA) VESA(XGA) CVT(WXGA) CVT(WXGA) WXGA WSXGA SDTV 480P SDTV 480P HDTV 720P HDTV 720P HDTV 1080I HDTV 1080I HDTV 1080P HDTV 1080P HDTV 1080P DDC O O O O O

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

ADJUSTMENT INSTRUCTION
1. Application Range
This specification sheet is applied to 19"/ 22" LCD TV which is manufactured in TV (or Monitor) Factory or is produced on the basis of this data.
(5) filexxx.bin (7) .......OK

2. Specification
1) The adjustment is according to the order which is designated and which must be followed, according to the plan which can be changed only on agreeing. 2) Power Adjustment: Free Voltage 3) Magnetic Field Condition: Nil. 4) Input signal Unit: Product Specification Standard 5) Reserve after operation: Above 30 Minutes 6) Adjustment equipments: Color Analyzer(CA-210 or CA110), Pattern Generator (MSPG-925L or Equivalent), DDC Adjustment Jig equipment, SVC remote control.
(6)

3.2. ADC Process
(1) PC input ADC
1) Auto RGB Gain/Offset Adjustment - Convert to PC in Input-source - Signal equipment displays Output Voltage : 700 mVp-p Impress Resolution XGA (1024x 768 @ 60Hz) Model : 60 in Pattern Generator Pattern : 29 in Pattern Generator (MSPG-925 Series) [gray pattern that left & right is black and center is white signal (Refer below picture)].

3. Main PCB check process
* APC - After Manual-Insult, executing APC

3.1. Download
1) Execute ISP program "Mstar ISP Utility" and then click "Config" tab. 2) Set as below, and then click "Auto Detect" and check "OK" message. If display "Error", Check connect computer, jig, and set. 3) Click "Connect" tab. If display "Can't ", Check connect computer, jig, and set.


(1) (3)

Please check the speed : To use speed between from 200KHz to 400KHz (2) OK

- Adjust by commanding AUTO_COLOR _ADJUST (0xF1) 0x00 0x02 instruction. 2) Confirmation - We confirm whether "0xB6(RGB)" address of EEPROM "0xA2" is "0xAA" or not. - If "0xB6(RGB)" address of EEPROM "0xB4" isn't "0xAA", we adjust once more. - We can confirm the ADC values from "0xB0 ~ 0xB5(RGB)" addresses in a page "0xA2" * Manual ADC process using Service Remote control. After enter Service Mode by pushing "INSTART" key, execute "Auto-RGB" by pushing " G " key at "AutoRGB".

4) Click "Read" tab, and then load download file(XXXX.bin) by clicking "Read".

(2) COMPONENT input ADC
1) Component Gain/Offset Adjustment - Convert to Component in Input-source - Signal equipment displays Impress Resolution 480i MODEL : 209 in Pattern Generator (480i Mode) PATTERN : 08 in Pattern Generator(MSPG-925 Series) 5) Click "Auto" tab and set as below 6) click "Run". 7) After downloading, check "OK" message. Impress Resolution 1080i MODEL : 223 in Pattern Generator (1080i Mode) PATTERN : 08 in Pattern Generator(MSPG-925 Series)

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

4.5. DPM operation confirmation(MNT Model)
- Check if Power LED Color and Power Consumption operate as standard. (1) Set Input to RGB and connect D-sub cable to set. (2) Measurement Condition : ([email protected] 50/60Hz) (3) Confirm DPM operation at the state of screen without signal. - Adjust by commanding AUTO_COLOR_ADJUST (0xF1) 0x00 0x02 instruction. 2) Confirmation - We confirm whether "0xBF(480i)/ 0xC8(1080i)" address of EEPROM "0xA2" is "0xAA" or not. - If "0xBF(480i)/0xC8(1080i)" address of EEPROM "0xA2" isn't "0xAA", we adjust once more. - We can confirm the ADC values from "0xB9~0xBE (480i)/ 0XC2~(1080i)" addresses in a page "0xA2".

4.6 DDC EDID Write
1) Connect D-sub Signal Cable to D-Sub Jack. 2) Connect HDMI Signal Cable to HDMI Jack. 3) Write EDID DATA to EEPROM(24C02) by using DDC2B protocol. 4) Check whether written EDID data is correct or not. (refer to Product spec).

- EDID DATA
1) ANALOG DATA 128Byte

3.3. Function Check
A

Check display and sound
- Check Input and Signal items. (cf. work instructions) 1) TV 2) AV (CVBS/ S-Video) 4) COMPONENT (480i) 5) RGB (PC : 1024 x 768 @ 60hz) 6) HDMI 7) PC Audio In and H/P Out * Display and Sound check is executed by Remote control.

2) DIGITAL DATA 256Byte

4. Total Assembly line process
4.1. Adjustment Preparation
(1) Above 30 minutes H/run in RF no signal (2) 15 Pin D-Sub Jack is connected to the signal of Pattern Generator.

4.2. Confirm color coordinate of RGB
(1) Set Input to RGB. (2) Input signal : (1680 x 1050 @ 60Hz) Full white 216/255 gray level (85 IRE, Model : 122, Pattern : 78 at MSPG925L) (3) Set CSM : Cool (4) Confirm whether x = 0.2830.015, y = 0.2970.015(9300K 1000K) or not.

4.3. Confirm color coordinate of AV
(1) Set Input to AV (2) Input signal : CVBS - Full white 216/255 gray level (85 IRE, Model : 202, Pattern : 78 at MSPG925L) (3) Set PSM : Standard / CSM : Cool (4) Confirm whether x = 0.2830.015, y = 0.2970.015(9300K 1000K) or not.

a. All Data : HEXA Value b. Changeable Data * Serial No : Controlled/ Data : 01 ** Month : Controlled/ Data :00 *** Year : Controlled **** Check sum

4.7. HDCP SETTING
(High-Bandwidth Digital Contents Protection) 1) Connect D-sub Signal Cable to D-Sub Jack. 2) Input HDCP key with HDCP-key- in-program. 3) HDCP Key value is stored on EEPROM(AT24C512) which is 80~A1 addresses of 0xA0~0xA2 page. 4) AC off/ on and on HDCP button of MSPG925 and confirm whether picture is displayed or not of using MSPG925. 5) HDCP Key value is different among the sets.

4.4. Confirm color coordinate of component
(1) Set Input to COMPONENT. (2) Input signal : 480P - Full white 216/255 gray level (85 IRE Model : 212, Pattern : 78 at MSPG925L) (3) Set PSM : Standard / CSM : Cool (4) Confirm whether x = 0.2830.015, y = 0.2970.015(9300K 1000K) or not.

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

4.8. Outgoing condition Configuration
1) After all function test., press IN-STOP Key by SVC Remote control. And Make Ship Condition. 2) When pressing IN-STOP key by SVC remote control, Red LED are blinked alternatively. And then Automatically turn off. (Must not AC power OFF during blinking)

4.9. Internal pressure
- Confirm whether is normal or not when between power board's ac block and GND is impacted on 1.5kV(dc) or 2.2kV(dc) for one second.

4.10. Option data setting (SVC OSD setting)
(1) PAL Model (Change by Suffix)
INSTART MENU ADJ MENU

5. Adjustment Command
5.1. Adjustment Commands(LENGTH=84)
Adjustment Contents FACTORY ON FACTORY OFF EEPROM ALL INIT. EEPROM Read EEPROM Write COLOR SAVE (R/G/B cutoff, Drive, Contrast, Bright) H POSITION V POSITION CLOCK PHASE R DRIVE G DRIVE B DRIVE R CUTOFF G CUTOFF B CUTOFF BRIGHT CONTRAST AUTO_COLOR_ADJUST CHANGE_COLOR_TEMP FACTORY_DEFAULT AUTO_INPUT CHANGE CMD(hex) E0 E2 E4 E7 E8 EB 20 30 90 92 16 18 1A 80 82 84 10 12 F1 F2 F3 F4 ADR 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 VAL 00 00 00 00 data 00 00 100 00 100 00 100 00 100 00 FF 00 FF 00 FF 00 7F 00 7F 00 7F 00 3F 00 - 64 02 0,1,2,3 00 0,1,2,4 Bright adjustment Luminance adjustment Auto COLOR Adjustment 0 : COOL, 1 : NORMAL, 2 : WARM, 3 : USER Factory mode off & II_SW is "1" & Input change to " TV" 0 : TV, 1 : AV1, 2 : AV2, 3 : Component, 4 : RGB, 5 : DVI Offset adjustment Drive adjustment Factory mode on Factory mode off EEPROM All clear EEPROM Read EEPROM Write by some values Color Save They have different range each mode, FOS Adjustment. Description

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

5.2 EEPROM DATA READ
(1) Signal Table
Delay 100ms

128 Bytes

(2) Command Set
Adjustment contents CMD(hex) ADH(hex) ADL(hex) EEPROM READ E7 A0 0 80 A2 0 80 A4 0 80 A6 0 80 Details 0-Page 0~7F Read 0-Page 80~FF Read 1-Page 0~7F Read 1-Page 80~FF Read 2-Page 0~7F Read 2-Page 80~FF Read 3-Page 0~7F Read 3-Page 80~FF Read

* Purpose : To read the appointment Address of E2PROM by 128(80h)-byte

5.3. E2PROM Data Write
(1) Signal Table

LEN : 84h+Bytes CMD : 8Eh ADH : E 2PROM Slave Address(A0,A2,A4,A6,A8), Not 00h(Reserved by BufferToEEPROM) ADL : E2PROM Sub Address(00~FF) Data : Write data

(2) Command Set
Adjustment contents EEPROM WRITE CMD(hex) E8 ADH(hex) 94 84+n Details 16-Byte Write n-byte Write

* Purpose 1) EDID write : 16-byte by 16-byte, 8 order (128-byte) write(TO "00 7F" of "EEPROM Page A4"). 2) FOS Default write : 16-mode data (HFh, HFl, VF, STD, HP, VP, Clk, ClkPh, PhFine) write. 3) Random Data write : write the appointment Address of E2PROM.

5.4. VRAM Read
1) Send CMD(70h) to read Video RAM value from MICOM And save its value to 128-Bytes Buffer.(Common Buffer for the use of EDID)

2) Delay 500ms. (Time to Wait and Read Video RAM from MICOM) 3) Be transmitted the contents of MICOM's 128-bytes Buffer to PC. (128th Data is the CheckSum of 127-bytes data : That's OK if the value of adding 128-bytes Data is Zero)
Data 128

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

TROUBLE SHOOTING
1. No Power (LED indicator off)

Check 15V or 5V of LIPS.

Fail

Check short of Main B/D or Change LIPS.

Pass Pass

Check output of Q701.

Fail Change Q701.

Check Output of IC705.

Fail Change IC705.

Pass

Fail Check LED Ass'y. Change LED Ass'y.

Pass

Check P304 & Connector.

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

2. No RASTER

Check LED status On Display Unit.

Fail Repeat No power (1) process.

Pass Check IC701,IC702,IC703, IC705,IC706,IC709, IC710. Pass

Fail

Change IC701, IC702, IC703, IC705, IC706, IC709, IC710.

Check Input/output of IC100.

Fail Change IC100.

Pass

Check inverter connector or inverter.

Fail Change inverter connector or inverter.

Pass

Check panel link cable or module.

Fail Change panel link cable or module.

Pass

Check Input source Cable and Jack.

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

3. No Raster on AV(AV/ COMPONENT/ S-Video, RGB-PC) signal
Pass

4. No Raster on TV(RF) Signal
Pass

Repeat No power (1) process.

Fail

Check the output of TU600.

Fail

Check 5V of TU600. Re-Soldering or change the defect part.

Pass

Pass

Check the signal of R602, R622, R623,R615,R616, R617,R640,R641, R642. Pass

Fail

Change L804, L1002, L1003, L1004.

Check input/output of IC100.

Fail

Re-soldering of Change defect part. Check the X100.

Pass

Check input source cable and jack.

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

5. No sound
Fail Change the source input.

Check the input Source.

Pass

Check input/ Output of IC100.

Fail

Re-soldering of Change the defect part. Check the X110

Pass

Check the input/ output of IC500

Fail Re-soldering or Change the defect part.

Pass

Fail Check the Speaker. Change the Speaker.

Pass

Check the Speaker wire.

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

AIR CABLE

1.2 V 3.3V

CLK_ 25 MHz
6 21 2AB2 87 2 A
MP2 30 5 DS
2. 5V VDD_DDR 1 2V

CLK_ MHz 12

1. 5V 3. 3V

3. 3V AVDD_DVI

15 V

2 TP DATA[ 0 7 ] 23"
[ 20, 22, 24, 26, 2 7 , 2 8 , 2 9 , 3 1 ] MSCL

1. MAIN BOARD

IF- P IF- N 2

5V
IF_AGC
G- 5V

VSB/ QAM Rec eiver
MSDA
CLK_2 00 MHz

HY5 D2 8 1 62 2 12 8 M( DRR)

19"/ 20"/ 22"

[ N: 11 ]

[1 2 ]

( LGDT33 04 ) 0ICTMLG01 9C
VCOM0

[ 3]

[ P: 10 ]

SCL[ 8 ]

SDA[ 7]

HY5 D2 8 1 6 22 1 2 8 M( DDR)
CVBS0 [ 4 4]

[1 6 ]

1. 0Vp-p

CVBS( ATV) SIF
SIFP0
Buf f er Buf f er
TUNER_CVBS

L C D

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes
SIFM0
CLK_5 7 MHz

ATSC/ NTSC Tuner ( TDVF H05 1F) LG Inno t ek

[1 5 ]

96d BuV

Rea r AV_1 V, LR IN1
( LGE18 54 B)
TXCLK-[ 2] TXCLK+[ 3]

Vid eo / Aud io SW

IN1

Rear S_1

YC

M- STAR

LVDS( 8Bit )
EEPROM( 5 1 2 K)

HDMI
HPDCTRL[ 12] DDCDA_SDA[ 14] DDCDA_SCL[ 15] POWER_HDMI[ 1 10 ]

BLOCK DIAGRAM

- 16 Co m p 1
EEPROM 0IMMR0 00 14 A

24 C5 1 2

0 IMMRAL02 5A
Fla sh( 3 2M) M2 5 L32 0 5 MI

3. 3 V

661 2B00015C

Co m p _1 YPb Pr/ LR
ST- 5V

6 61 2 J1 0 0 31 A

Po wer 1 5V/ ST 5 V KEY_CTL[ 1, 2 ]

PC IN
Po wer/ LIPS
R232C_Rx DDC_SCL/ UART_RX

PC( VGA)

6 6 30 G70 0 1 6A

AUR_IN[ 59] AUL_IN[ 58]

PC Ea rPho ne

Tx/ Rx
( MX2 32 ACSE)
R23 2C_Tx
Rx_In

DDC_SDA/ UART_TX

1 2V

Aud io _L

Aud io _R

0IPRP00009A 0IMX23 2162A

ST- 5 V

RS2 32C( Deb ug )

Tx_Out

D- AMP
( YDA13 8) 0 IPRPTI0 30 B
USB_DM[ 251] USB_DP[ 252] USB_OCD_N[ 83]

Head Pho ne

R OUT

6612F00099A

USB( SW Up g rad e)

Head Pho ne L OUT

LGE Internal Use Only

EAG31022001

2. DESCRIPTION
1. Video Control Unit (LGE1854B)
This unit has four functions. These are Transport Stream De-multiplexer, MPEG-2 A/V Decoder, NTSC/PAL/SECAM Video Decoder, Multi-Standard TV Sound Processor. Transport Stream De-multiplexer DE-MULTIPLEXEs TS signal that was DE-MODULATed from LGDT3304. MPEG-2 A/V Decoder supports HD(1080I,720P), SD(480P,480I) resolution, and MPEG-1,MPEG-2,DOLBY,AC-3 FORMAT. NTSC/PAL/SECAM Video Decoder decodes analog video signal (CVBS) and output RGB signal to VIDEO PROCESSOR. Multi-Standard TV Sound Processor switches and processes SIF (American BTSC, Korean A2 SYSTEM) and sound of inputted L/R audio. VIDEO PROCESSOR processes 3D-DEINTERLACING. OUTPUT INTERFACE part output each of 8 bits R,G,B as 1680x1050 resolution signal And It support SPREAD SPECTRUM for EMI.

2. Power Supply Unit
Power supply unit is composed DC-DC CONVERTER and REGULATOR that is converts 15V, 5V on power board at 12V, 5V, 3.3V, and 1.25V . 20LS7D-UA provides 15V to inverter part and 5V to LCD panel. 23LS7D-UA provides 24V to inverter part and 12V to LCD panel. And 5V is converted 3.3V , 1.25V , This Converted power support other IC parts on main board. AC inverter using 15V(20LS7D), 24V(23LS7D) makes AC 700 Vrms for driving the backlight ramp of LCD panel. 15V on power board is converted at 12V by DC-DC CONVERTER. And That is provided to SPEAKER. Also 15V on power board is converted at 5V by DC-DC CONVERTER. And That is provided to TUNER.

3. MICOM Unit.
MICOM Unit (8051 CORE) is within Video Controller and It is composed EEPROM storing system control data, Code memory, micom, and reset IC. At first, Micom judges input signal mode after judges horizontal and vertical frequency and polarity of inputted signal. Micom also set Register values with each IC proper for input signal mode and control . And the automatic regulation and horizontal/vertical location , clock/clock phase regulation which the user regulates, it will be able to regulate through OSD in order, it controls.

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

- 17 -

LGE Internal Use Only

EXPLODED VIEW

400

830

820

901

910

A2

A21

511

540

840

510

530

120

LV1

200

Copyright LG Electronics. Inc. All right reserved. Only for training and service purposes

300

501

500

902
LGE Internal Use Only

- 18 -

900

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

LGE Internal Use Only

Copyright 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes

LGE Internal Use Only

P/NO : MFL38731323

Dec., 2007 Printed in Korea