Toshiba 20VL44G, 20VL55, 20VL63 Schematic

TOSHIBA LC CHASSIS

20VL44G 20VL55 20VL63

TFT- LCD TV SERVICE MANUAL

CONTENTS

PAGES

Safety instructions

Technical specifications

Power rating and Panel Specifications

Remote control explanations

Service Menu of the TV

Set appearrances

Block diagram of the VCTI

Block diagram of Microcontroller (Genesis)

Block diagram of power supply

Data sheet of important IC’s

Service mode items and explanations

Replacement part List

Frequency list of channels

SAFETY PRECAUTIONS

GENERAL GUIDELINES

1. Always use the manufacturer’s replacement safety

components. The critical safety components marked with on the schematics diagrams should not be

by other substitutes. Other substitute may create the electrical shock , fire or other hazards. Take attention to replace the spacers with the originals. Furthermore where a short circuit has occurred , replace those components that indicate evidence of overheating.

2. After servicing , see that all the protective devices

such as insulation barriers, insulation papers, shields and isolation R-C combinations are correctly installed.

3. When the receiver is not being used for a long time

of period of time , unplug the power cord of the Adaptor from the AC outlet.

Color TFT LCD Module is very sensitive both electrically and physically.Users, therefore, are requested to follow the “Guidance of handling color TFT LCD Module”on the followings.

1 - Be careful not to make scratch on the

polarizer.

Surface of polarizer is soft and can be physically

damaged easily.

Please do not touch, push or rub polarizer surface

with materials over HB hardness.

2 - Keep clean the surface.

Please wear rubber glove when touch the surface of LCD screen. Please use so ft and anti-static material as cleaner.

3 - Keep out of water.

Water on/in the LCD may cause electrical short or corrosion. Please wipe out dry or water carefully.

4 - Prevent swift Temperature &

Humidity change.

Instantaneous temperature and/or humidity change can make dew or ice which cause nonconformance such as malfunction.

5 High temperature & high humidity reduce the life-time.

LCD is not proper to be used at high temperature and high humidity. Please keep specified temperature and humidity condition.

6 - Keep out of Corrosive Gas.

Corrosive gas effect the polarizer and the circuit chemically and cause defects accordingly.

7 - Electrostatic discharge can make

Damage

There are electro-static sensitive components such as CMOS in LCD Module. Please earth human body when handle the LCD.In addition, please do not touch the interface connector pin with bare.

8 - Do not operate for a long time under

the same pattern

Operating LCD for a long time under the same pattern can cause image persistence and can damage it. Please follow following guidance.

1. Turn the power off when do not use.

2. Change the pattern periodically.

SPECIFICATIONS

Receiving System PAL B/G+I+D/K SECAM L/L' Tuning System PLL FST Comb Filter Adaptive 4H\2H LTI, CTI Filters Optional Sync On Green (SOG) support on graphics YES Scaling Upto SXGA at 75Hz Stereo Decoding (German A2, Nicam, BTSC) German A2, Nicam Virtual Dolby Optional Subwoofer Optional YPbPr In (Progressive) Through D-sub 15 conn. Optional Number of speakers 2 (L+R)

Level (1.5, 2.5, Teleweb) Teletext 1.5

No Text- Optional

Teletext

Supported Menu Languages

Type

List Mode Optional Page Memory 10p

ENGLISH, DEUTSCH, DUTCH, FRANCAIS,

ESPAÑOL, ITALIANO, PORTUGUESA,

EHΛΛNIKA, SVENSKA, NORSK, SUOMI,

TÜRKÇE, POLSKI, MAGYAR, ČEŠTINA,

ROMANESTE, SLOVENČINA, DANSK,

SERBIAN, PЧCCKИЙ, Bulgarian, Crotian

Fast Text -Optional

Top Text&Fast-Default

>> 22 Languages

4:3 YES

16:9

14:9 Picture Formats (4:3, 16:9, 14:9, Panorama, LetterBox, Subtitle)

WSS (Wide Screen Signalling) Optional ATS (Automatic Tuning System) Frequency Search Manual Search Frequency Search AFT (Auto Fine Tuning) YES Number of Program Storage 100 No Ident Timer YES Equalizer YES AVL (Automatic Volume Level) YES Sound Status Memory YES Picture Status Memory YES Zapping\Swap Optional Panel Lock YES Picture Format Switching Through Scart (Pin 8) YES Auto RGB Detect Through Scart (Pin 16) YES Timer On\Off or Sleep Optional Picture Smart Modes YES Sound Smart Modes YES Simple Hotel Mode Optional

Wake Up in PC

Panorama NO

Letterbox

Subtitle

Zoom NO

Stby to On in PC mode

when last watched is PC

Stby to On automatically

when PC signal is available

4:3 Panels: Depends on LCD

16:9 Panels: YES

4:3 Panels: NO

16: 9 Panels: Depends on LCD

4:3 Panels: NO

16: 9 Panels: Depends on LCD

4:3 Panels: NO

16: 9 Panels: Depends on LCD

Optional

Memory Card Reader Optional

(

POWER RATING AND PANEL SPECIFICATION

15" 17" 20" 22W" 26" 27" 32"

Adaptor Input

Current rating

Power consumptions

St-By Power Consum

Input Range

Audio Output Power

%10) THD

Manufacturer

Interface

Resolution

Brightness (cd/m2)>

Contrast>

tion

12V 12V 15V 24V Built-in Power Built-in Power Built-in Power

3A 4A 4A 3A

48W 60W 75W 100W 130W 130W 130W

<3W <3W <3W <3W <3W <3W <3W

100-240V/50, 60Hz 100-240V/50, 60Hz 100-240V/50, 60Hz 100-240V/50, 60H

2X2W 2X3W 2X3W 2X7W 2X7W 2X7W Samsung CMO AUO Double TTL\Single LVDS

XGA (1024x768)

250 300 500 450 450 550 550

300 400 500 500 400 600 600

Samsung CMO AUO Samsung

Dual LVDS

SXGA (1280x1024)

Single TTL\Single LVDS SVGA (800x600) VGA (640x480)

Single LVDS Singlel LVDS Singel LVDS Singel LVDS

WXGA (1280x720)

100-240V/50, 60Hz 100-240V/50, 60H100-240V/50, 60Hz

Samsung LG-Philips AUO

WXGA (1280x768)

Chimei Chimei

WXGA (1280x720)

REMOTE CONTROL

123

5 19

6 7

11 12

13 14

15 16

456

789

AV SWAP

TXT/MIX MENU

VOL+

‹

PC TV

VOL-

PR+

PR-

1.Picture Format ( )

2. Temporary mute of volume (MUTE) (

172

3.Numeric buttons

4. Audio/Video (AV) (

5.PC mode transition (

)

6. Teletext / MIX / TV choice buttons (

7. Up (Menu -Teletext) ( )

)

8. Left (Menu) (

9. Volume UP (

10. Volume DOWN (

11. Red Fastext Button

12. Green Fastext Button

13. Index Button (P100) (

21 22

14. Question/Answer button (REVEAL) (

15. UPDATE Button (

16. SUB PAGE Button (

17. STAND-BY Button (

18. Return to Selected Program Button (SWAP) (

26 27

19. TV mode transition button (

20. Menu Button (

21. OK Button (

22. Right (Menu) (

)

23. Down (Menu/Teletext) (

24. Program up button (P+) (

25. Program down button (P-) (

)

26. Blue Fastext Button

27. Yellow Fastext Button

28. STOP Button (

)

29. Teletext enlarge button (DOUBLE) (

30. Equalizer selection button (

31. Picture control button (

)

SERVICE MENU OF THE TV

DEFAULT VALUES OR

ITEM NAME

OPTIONS/ VALUES

OPTIONS

SCART 2 ON/OFF OFF

FAV ON/OFF ON

SVHS ON/OFF ON

HOTEL MODE ON/OFF OFF

STBY RECALL ON/OFF OFF

RECALL LAST AV ON/OFF OFF

MSP CARRIER MUTE ON/OFF OFF

WSS RF ON/OFF ON

AUTO AV 16:9 ON/OFF ON

FIRST ATS ON/OFF OFF

BACKLIGHT POL ON/OFF OFF

FACTORY MODE ON/OFF OFF

ADJUSTMENTS

SETUP

WHITE R 0-255 128

WHITE G 0-255 128

WHITE B 0-255 128

BRIGHTNESS 0-255 130

CONTRAST 0-257 158

COLOR 0-255 128

PRESCALE FM 0-127 37

PRESCALE NICAM 0-127 63

PRESCALE SCART 0-127 27

HOTEL VOLUME 0-63 16

AGC 0-31 23

FACTORY RESET

SW DOWNLOAD

SELECTIONS

TUNER TYPE

TELETEXT

PHILIPS , SAMSUNG

FAST&TOP , NO TEXT ,FAST

PHILIPS

FAST&TOP

TIMER MODE

MSP CLIP

SWAP/ZAPP DOLBY VIRTUEL

SLEEP TIMER OFF TIMER

REDUCE VOL REDUCE

VOLUME

ON/OFF OFF

SLEEP TIMER

REDUCE VOL

ZAPP

LC (L5C) SERVICE MENU

Service Menu is entered by pressing 9, 3, 0, 1 keys on the remote controller when the Picture icon is highlighted in the Main Menu.

Service Menu has 3 sub-menus. These are:

• Options

• Adjustments

• Selections.

Navigation through these menus can be done by pressing OK button. Every adjustment made in this menu is saved automatically.

OPTIONS

Options are adjustments that the user can select On or Off.

• SCART 2

• FAV

• SVHS

• HOTEL MODE

• STAND BY

• MSP CARRIER MUTE

• WSS SCART

• FIRST ATS

SCART 2 / FAV / SVHS

If a source is disabled in the Service Menu, it will be skipped during source switches. If SCART2 is enabled, SW assumes that the FAV source share the same path as the SVHS source on the HW. If it is disabled, it is assumed that FAV and SVHS share separate paths. TUNER and SCART1 are enabled by default.

HOTEL MODE

Enabling Hotel Mode has two effects. First, SETUP menu is no longer accessible by the user. Second, maximum adjustable volume value is limited to HOTEL VOLUME value. This value can be adjusted in the ADJUSTMENTS sub-menu of the Service Menu.

STAND BY

If this Option is OFF, the TV will stay in Stand By mode after a Power On. If this Option is ON, the TV will recall its last stand by status before the Power Off, and switch on from Stand By automatically, if the last state was ‘Stand by On’.

MSP CARRIER MUTE

If this option is ON, sound processor’s carrier mute functionality will be enabled. The MSP will mute the sound automatically if the signal quality is bad. Setting this option Off will disable this functionality.

ATS

If this option is set to ON, TV will display Country Selection menu in the next start. After some country is selected, the user will be prompted for the start of AutoProgramming process.

ADJUSTMENTS

This sub-menu contains numeric adjustments. These items are:

• WHITE R

• WHITE G

• WHITE B

• BRIGHTNESS

• CONTRAST

• COLOR

• PRESCALE FM

• PRESCALE NICAM

• PRESCALE SCART

• HOTEL VOLUME

WHITE R / WHITE G / WHITE B

These are used for color bias adjustment. Unlike other items in the service menu, changes will take effect immediately.

PRESCALE FM / PRESCALE NICAM / PRESCALE SCART

These are prescale values that will be used for the initialization of the sound processor (MSP), at the next switch on.

HOTEL VOLUME

This value is used as the volume limit, when the Hotel Mode is on.

SELECTIONS

This sub-menu contains selections.

• TUNER TYPE SAMSUNG / PHILIPS

• TELETEXT NO TEXT / FAST / FAST&TOP

• MSP CLIP REDUCE VOL / REDUCE TONE

TUNER TYPE

One of two supported tuner can be selected from this item. System must be restarted for this change to take effect.

TELETEXT

NO TEXT: Teletext is totally disabled. TXT/MIX button will not be functional. AUTO picture format mode

will be disabled in RF, F-AV and SHVS modes. Naming and sorting functionality during Autoprogramming will be disabled.

FAST: TOPtext functionality will be disabled.

FAST&TOP: TOPtext functionality is enabled.

TIMER MODE

If OFF TIMER is selected, the user will be able to enter time of the day info for the TV to switch off. If SLEEP TIMER is selected, the user can specify some time period, after which the TV will go to stand by automatically.

MSP CLIP

This selection identifies which method will be used by the sound processor to prevent clipping effects on volume.

AUTOPROGRAMMING

When the user selects the Autoprogram item in Setup menu, Country Selection menu is opened. The user must select a country before the Autoprogramming starts. Broadcast system will be selected according to the country selected.

Broadcast systems according to countries:

BELGIUM BG + L CROATIA BG CZECH REP. DK DENMARK BG FINLAND BG FRANCE L + BG GERMANY BG GREECE BG HUNGARY DK IRELAND I ITALY BG NETHERLANDS BG NORWAY BG POLAND DK PORTUGAL BG SPAIN BG SWEDEN BG SWITZERLAND BG + L TURKEY BG UNITED KINGDOM I

For countries France, Belgium and Switzerland, autoprogramming is done twice. For Belgium and Switzerland, first BG channels will be searched, after the search in BG is done, searching will restart for L standard. If the selected country is France, the sequence of standards is reversed, thus, first L then BG.

TELETEXT LANGUAGES

L5C SW decides which teletext language group will be used for teletext decoding, according to the country selected for autoprogramming.Teletext languages according to countries:

EAST EUROPE:CROATIA ,CZECH_REP, POLAND

WEST EUROPE: BELGIUM ,DENMARK, FINLAND, UK, FRANCE, GERMANY,

IRELAND ,ITALY ,NETHERLANDS, NORWAY, PORTUGAL,SPAIN, SWEDEN, SWITZERLAND, HUNGARY

TURKISH-GREEK:GREECE TURKEY

PC MODE

PC mode can be entered by pressing PC button on the remote controller. User can return back to TV mode by pressing the PC or TV buttons.

After the switching to PC mode, VGA input will be displayed on screen, as soon as the mode (input resolution and frequency) is determined.

If there is no input from the VGA input, NO SIGNAL dialog will be displayed for 15 seconds. At the end of this period if there is no signal from VGA input, the TV will go to Sleep State. While in the sleep state, the TV will keep monitoring the VGA input. If VGA signal is detected, the TV will wake from Sleep State, to PC mode. Alternatively, the user may select to switch the TV on from Sleep State, just like switching on from Stand-by. In this case, the set will switch on from TV mode.

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