Viewsonic N2750W-2G Schematic

Service Manual

ViewSonic N2750w-2G

Model No. VS11404-1G

27” LCD TV

(N2750w-2G_SM Rev. 1a Sep. 2006)

ViewSonic® 381 Brea Canyon Road, Walnut, California 91789 USA - [phone]

Copyright

Copyright © 2006 by ViewSonic Corporation. All rights reserved. No part of this publication may be
reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or
computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical,
manual or otherwise, without the prior written permission of ViewSonic Corporation.

Disclaimer

ViewSonic makes no representations or war r ant ies, either expressed or impl ied, with respect to the contents
hereof and specifically disclaims any warranty of merchantability or fitness for any particular purpose. Further,
ViewSonic reserves the right to revise this publication and to make changes from time to time in the contents
hereof without obligation of ViewSonic to notify any person of such revision or changes.

Trademarks

Optiquest is a registered trademark of ViewSonic Corporation.
ViewSonic is a registered trademark of ViewSonic Corporation.
All other trademarks used within this document are the property of their respective owners.

Revision History

Revision SM Editing Date ECR Number Description of Changes Editor

1a 09/22/06 Initial Release Sophia Kao

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TABLE OF CONTENTS

1. Precautions and Safety Notices.................................................................1

2. Specification.................................................................................................4

3. Front Panel Function Control Description................................................ 10

4. Circuit Description.......................................................................................20

5. Adjustment Procedure................................................................................22

6. Trouble Shooting Flow Chart................................................................ .....48

7. Block Diagram.............................................................................................52

8. Schematic Diagrams....................................................................................53

9. PCB Layout Diagrams.................................................................................65

10. Exploded Diagram And Exploded Parts List...........................................71

11. Recommend Spare Parts List...................................................................74

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1. Precautions and Safety Notices

1. Appropriate Operation

(1) Turn off the product before cleaning.
(2) Use only a dry soft cloth when cleaning the LCD panel surface.
(3) Use a soft cloth soaked with mild detergent to clean the display housing.
(4) Disconnect the power plug from AC outlet if the product is not used for a long period of

time.

(5) If smoke, abnormal noise, or strange odor is present, immediately switch the LCD display

off.
(6) Do not touch the LCD panel surface with sharp or hard objects.
(7) Do not place heavy objects on the LCD display, video cable, or power cord.
(8) Do not use abrasive cleaners, waxes or solvents for your cleaning.
(9) Do not operate the product under the following conditions:

- Extremely hot, cold or humid environment.

- Areas susceptible to excessive dust and dirt.

- Near any appliance generating a strong magnetic field.

- Place in direct sunlight.

2. Caution

No modification of any circuit should be attempted. Service work should only be performed after
you are thoroughly familiar with all of the following safety checks and servicing guidelines.

3. Safety Check

Care should be taken while servicing this LCD display. Because of the high voltage used in the
inverter circuit, the voltage is exposed in such areas as the associated transformer circuits.

4. Power Supply Requirements

The external AC power operating range shall be from 90 to 264Vac

5. LCD Module Handling Precautions

5.1. Handling Precautions

(1) Since front polarizer is easily damaged, pay attention not to scratch it.
(2) Be sure to turn off power supply when inserting or disconnecting from input connector.
(3) Wipe off water drop immediately. Long contact with water may cause discoloration or

spots.
(4) When the panel surface is soiled, wipe it with absorbent cotton or other soft cloth.
(5) Since the panel is made of glass, it may break or crack if dropped or bumped on hard

surface.
(6) Since CMOS LSI is used in this module, take care of static electricity and insure human

earth when handling.
(7) Do not open nor modify the Module Assembly.
(8) Do not press the reflector sheet at the back of the module to any directions.
(9) In case if a Module has to be put back into the packing container slot after once it was

taken out from the container, do not press the center of the CCFL Reflector edge.

Instead, press at the far ends of the CFL Reflector edge softly. Otherwise the TFT

Module may be damaged.
(10) At the insertion or removal of the Signal Interface Connector, be sure not to rotate nor

tilt the Interface Connector of the TFT Module.
(11) After installation of the TFT Module into an enclosure (LCD monitor housing, for

example), do not twist nor bend the TFT Module even momentary. At designing the

enclosure, it should be taken into consideration that no bending/twisting forces are

applied to the TFT Module from outside. Otherwise the TFT Module may be damaged.
(12) Cold cathode fluorescent lamp in LCD contains a small amount of mercury. Please

follow local ordinances or regulations for disposal.
(13) Small amount of materials having no flammability grade is used in the LCD module.

The LCD module should be supplied by power complied with requirements of Limited

Power Source (IEC60950 or UL1950), or be applied exemption.

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(14) The LCD module is designed so that the CFL in it is supplied by Limited Current

Circuit (IEC60950 or UL1950). Do not connect the CFL in Hazardous Voltage Circuit.

5.2. Handling and Placing Methods

Correct Methods: Incorrect Methods:

Only touch the metal frame of the LCD panel
or the front cover of the monitor. Do not touch
the surface of the polarizer.

Take out the monitor with cushions Taking out the monitor by grasping the LCD

Surface of the LCD panel is pressed by fingers

and that may cause “Mura”

panel. That may cause “Mura”

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Place the monitor on a clean and soft foam pad. Placing the monitor on foreign objects. That

could scratch the surface of the panel or cause
“Mura”

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2. Specification

Parameter Specification

LCD Type

LCD Interface 1-Channel LVDS
Resolution (Native) WXGA, 1366 x 768
Display Area 27” diagonal; 596.259 (H) x 335.232 (V) mm.
Pixel Pitch 0.4365(H) × 0.4365(V) mm
Viewing Angle
Contrast Ratio 1000:1 (Typ); 800:1 (Min)
Brightness 550 nits (Typ.); 450 nits (Min)
Response Time 8ms, (Typical), g-g
Color Gamut NTSC 75% Typ
Brightness Uniformity 1.3 (Max), measured per panel spec.
Chromaticity (CIE1931) White-x:0.285,White-y:0.293 (Standard Mode Only)
Colors 16.7M (8-bit)
Surface Treatment Hard coating (3H)
Backlight 14 CCFLs (Cold cathode Fluorescent Lamp)

Panel Acceptance

Front Screen Artifacts

Note: Panel performance characteristics “ MUST BE” met in all display modes/inputs at
standard test conditions.

1. RF Tuner

RF tuner of this product shall be provided by” LG TAPQ-S701D” and “LG TAPE-S701D” for
PAL/SECAM. The following table defines this tuner specification.

Parameter Specification

RF Input Level 0 ~ 15dBmV

RF Tuning Range

RF Tuner Sensitivity (S/N Ratio at un-weight) -45 dB (min.)

Channel Bandwidth

CVBS Characteristics:
Video Amplitude Signal
DC Level Sync Pulse Typical. 0.35 V
Audio Characteristics:
AF Output Level Measured via LP 20 kHz
Filter, RMS Decoder,
50us De-emphasis
THD
S/N
Compatible system TUNER SECAM/PAL

a-Si TFT Active Matrix Wide Color, Transmissive Mode, Normally
Black

H = +/- 88°, V = +/- 88° with CR≥20 (Typical)

Refer to the panel acceptance criteria specification.
Note: Intermittent and/or Display Pattern defects which result in
further bright or dark dots will be counted individually against the
above specification.
VS Standard:
a.) No Visible Streaking, Sag or Smearing artifacts when driven by

the specified video cards (see 7.1 General Test Equipment) in the
primary mode (VGA at 60 Hz) and after user adjustment

b.) No image drift or lose fine-tune settings due to panel temperature

change

CCIR B/G Cable 48.25~463.25
CCIR B/G Air 48.25~855.25
CCIR D/K Air+Cable 49.75~863.25
CCIR I CABLE 48.25~463.25
CCIR I AIR 48.25~855.25

PAL: 7/8 MHz Maximum
SECAM: 8 MHz Maximum

0.7(min.)–1.3(max.) V

Typical. 0.45Vrms

10% (max.)
40 dB (min.)

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2. Video

Built-in A/D converter shall provide analog to digital converter for this product.

Input Parameter Specification

CVBS Characteristics:
Video Amplitude Signal
DC Level Sync Pulse
S-Video Characteristics:
Video Amplitude Signal
DC Level Sync Pulse
Y, Cb,Cr Characteristics:
Video Amplitude Signal
DC Level Sync Pulse

0.7(min.)–1.1(max.) V
Typical. 0.3 Vp-p

Y : 1.0Vp-p W / Neg. Sync (IN 75 Ω )
C : 0.285Vp-p (IN 75 Ω )

Y:1.0Vp-p(IN 75 Ω)
Pb:0.7 Vp-p(IN 75 Ω),Pr:0.7 Vp-p(IN 75 Ω)

Video Bandwidth PAL: 7/8 MHz Maximum SECAM: 8 MHz Maximum
HDMI Characteristics Panel Link T.M.D.S HDMI-1.1
RGB Characteristics:
Signal Type
Sync Type
Input Signal Rating
Sync Level:
Frequency Range
Pixel Color

Analog VGA
TTL, Separate Sync, with 4.7KΩ pull-down resistors
1250mv Max without damage to the product, 0-700 mv Full
Range

2.5-5.25 V
Horizontal: 30-80K Hz, Vertical: 50-75 Hz
16 M

3. Audio

Audio amp of this product shall be provided by “TI” with a Model Number of

TPA3002D2PHPR(TQFP48) , MST5151A-LF for N2750w-2G shall be used as sound
processor. In addition, a pair of speakers shall be integrated within this product. The audio
signals of this product shall comply with the specification listed in the following table.

Parameter Specification

Phone Jack out
Tuner Input Base band Input
Speaker Power Output Max

Rating

Speaker Impedance

Line In Per Tuner Spec

Line Out

Flatness of Amplitude Response
(100Hz ~ 10KHz)
Total Harmonic Distortion
(1KHz @1W)
Signal to Noise (1KHz @1W) 30 dB (40Hz to 15KHz) 40dB(400Hz to 20 kHz)

5 W x 2 at 10% T.H.D
Distortion
main spk :8 Ω
Treble spk :8 Ω

5W x 2 at 10% T.H.D.
Distortion
main spk :8 Ω
Treble spk :8 Ω
500 mV rms (Typ)

1.6 V rms (Max)

Impedance: 600 ohms
500 mVrms +/- 10%
@1K Hz tone (with +/-25k Hz
deviation at input, volume
with non-attenuation and
loading with 47k Ohm)

500 mVrms +/- 10%

@1K Hz tone (with +/-25k Hz

deviation at input, volume

with non-attenuation and

loading with 47k Ohm)

+/- 3 db (at 1KHz @1W) +/- 3 db (at 1KHz @1W)

2% 2%

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4. Electrical

The following table defines the electrical specification of this product.

ELECTRICAL SPECIFICATION

Power Input Voltage Range 100-240VAC +/- 10% Wide Range
Input Frequency Range 47-63 Hz
Input Current 3.0A @ 115VAC // 1.5A @ 230VAC

Max in < 80A (with fully loaded power supply) at 230Vac

Power Supply Inrush

Shall not result in permanent failure of power supply
(including blown fuse)

Power Consumption: Normal Normal: 150 W (Max) // Stand by: < 5 W

There shall be no visible interference between power

Interference with RF and Video

supply, RF and video signals. This applies to all available
RF channels and video modes.

Electromagnetic Compatibility

Power Supply Transient Immunity
(Supply Transients and Outage)

Surge Immunity Test

Power Supply Missing Cycle Immunity

This product shall adhere to the compatibility and
immunity specifications in BC.
Able to withstand an IEC6100-4-4(1995) ring wave with no
damage.
Able to withstand 1.25X nominal Line Voltage for one
cycle with no damage.
Function properly without reset or visible screen artifact
when 1/3 cycle of AC Power is randomly missing.
Power supply shall not produce any audible noise during

Power Supply Acoustics

startup and normal operation. Audible shall define to be
in compliance with ISO 7779 (DIN EN27779: 1991) .

Power Switch noise shall be Excluded.
Efficiency >= 70% @ full load, nominal line
Leakage Current <0.5mA @ 240VAC
Power Saving(DPMS) N/A
Recovery Time < 3 sec.
Power Factor Correction Compliant with EN60065

5. Firmware & OSD

The product firmware of VS11404-1G shall have a firmware version of V:P01. Any
changes/revisions afterward shall also be pre-approved by ViewSonic in written. For
VS11404-1G, its firmware shall have a built-in frequency table for PAL/SECAM
off-air TV/CATV implementation.

All audio/video and other output adjustments shall be performed by using an On Screen
Display (OSD) via a Remote Control Unit (RCU) adjustments. The following tables list
the OSD functions supported by VS11404-1G.

OSD Table for

VS11404-1G

Items Description
TV/VIDEO MODE

Brightness Adjust the Black levels from 0 to 100
Contrast Adjust the White levels from 0 to 100
Sharpness Adjust the Sharpness levels from 0 to 100
Color Adjust the Color from light to heavy
Tint Adjust from Red from Green
Fresh Tone Adjust the skin from shallow to deep
Color Temperature Select the color temperature between warm,Normal or cool.
Bass Adjust the Low Frequency from light to heavy
Treble Adjust the Hi Frequency from light to heavy
Balance Adjust the Speaker output from left to right
Auto scan To auto scan the TV channels (TV or CATV) and scan TV system.
Manual store To adjust the channel search and fine tune or system select.
Name To edit channel name
Sort Channel exchange
Main source Main source select.

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H-position To adjust H position
V-position To adjust V position
OSD position-H Adjust OSD horizontal position
OSD position-V Adjust OSD vertical position
Duration To adjust the OSD display delay time.
Halftone To adjust the OSD transparency level.
Language Select OSD language

PC MODE

Auto adjust Automatically adjust the clock,phase,position,and color.
Brightness Adjust the Black levels from 0 to 100
Contrast Adjust the White levels from 0 to 100
Image H.position Adjust the horizontal positions
Image V.position Adjust the vertical positions
Clock To adjust the clock delay time
Phase To adjust the phase delay time

Color mode To select the preset color temperature or user color setting.
Parental TV
Channel Add/Del TV channel Add or Delete

RCU Key function

Power Soft power on or off
Picture Picture effect selections on Cinema,Sport,Vivid,Hi-bright,and User
Sound Sound effect selections on Rock,POP,Live,Dance,Techno,Classic,Soft,and

TV-DTV Swap analog TV(NTSC) and DTV(ATSC).Swap to TV when in other

MTS Selcetion on Mono,Stereo and Sap sound
Sleep Set TV Power off time
Info Display current source input information
Mute Mute On or Off sound
0 ~ 9, 100/- Direct channel key number
Return Return to last channel
Guide Electric program guide on Digital TV
CH up/down Adjust channel up or channel down
Volume Adjust the Volume levels
Up/Down/Left/Right
arrows
Fav.ch Switch to favorite channel
Fav.A/D Add or Del favorite channel
Menu Turn On or Off OSD main menu or exit current menu
Input Selections Input Source
Freeze To freeze the current image
Zoom Enlarge or shrink current image on the screen
Wide Adjust image size on Full, Wide1, Wide2, Wide3, 4:3, 16:9, No scale,

Enter Confirm the selection
PIP/POP Toggle to select PIP or POP function
P.Pos Adjust picture position of sub source during in PIP
P.size Adjust image size of sub source during in PIP
Swap Switch between main screen and sub screen during in PIP or POP
P.input Sub source selection during in PIP or POP
C.C Displaying captions during closed caption source and closed caption mode

V-chip Set V-chip rating

User

source

Select or adjust the function of OSD

Normal

select

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6. Remote Control Unit (RCU)

An IR remote control unit shall accompany this product along with battery. In addition,
this remote control unit shall have an operational distance of 5 meters and an operational
angle of 15 degrees for both horizontal and vertical.

Parameter Specification

Type IR; Made by Bontech Electronics Co., Ltd.

Range

Life Testing
(Buttons)

Color

Key
Functions

7. Mechanical

The following table defines the mechanical specifications of this product for both chassis and
cabinet.

Dimension W=680mm, H=540mm and D=243mm
Net Weight 14.6kg
Chassis Plastic Material ABS (CABS HB / ABS VO / PC+ABS)
External Plastic Chassis
Components
Internal Plastic Cabinet
Components
Exterior Chassis Color “Silver” Pantone 877C
Chassis Component’s Color
Difference
Chassis Color Drift Due to
UV-Light

Chassis Texture Front Bezel:N/A ; Back Cover:MT-11020
Molded Plastic Workmanship shall be inspected according to ViewSonic

Screen Printed Parts, Bird Logo
Recess
Rear Label A label identifying the product name, model/serial number

Off axis ± 10° ≥ 5M
On axis: ≥ 7M
100,000 cycle operations at a rate of 20~30 cycle / minute without load (with
battery)
Painting Color - PANTONE 877C (Silver for front bezel & back cover)
Power Key - PANTONE 186C (RED)
Key Pads – PANTONE 431C & PANTONE 432C(Cool Gray)
Texts Printed on Silver Cover-PANTONE 5455C(Light Gray),PANTONE
433C(Black),PANTONE 129C(Yellow)
(Notes:Above color spec can refer Bontech documents;VS US dwg color
RRC1200-0801L_R2)
AV Control: Volume-Up/Dowm,CH/PG-Up/Down,Channel
Up/Down,Mute,PIP/POP,Wide,Sleep/Info,P.Source,Swap,Power,Source.
Numeric: 0~9 numeric keys,Recall.
Navigation: Up,Down,Left,Right,Enter,Menu.
Smart sound and Smart video hot key

Parameter Specification

Plastic Chassis, Cover, Stand, Lens and Button

N/A

N/A (Only silver color on chassis)

The color drift due to UL-Light shall be less than 10 “Delta
E” in the 1976 CIE L*a*b color space. Testing shall be
performed according to the requirements of ASTM Test
Method D4459-93.

Molded Plastic Parts Specification, VSCMPPSPEC001V1.2.
Artwork shall be provided and confirmed by ViewSonic.

and FCC ID/Logo shall be placed into the rear label recess
located on the rear panel of the chassis.

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Wall- Mount 200mmx100mm VESA high hole (n=6), M4 x 10mm , pitch

=0.75mm screw mounting kit not included.

Sample Sample of textured color chips, plastic material specification,

and Material Safety Data Sheets shall be submitted to

ViewSonic prior to Mass Production Release.
In addition, all exterior surfaces shall have uniform texture/color. The maximum acceptable
gap between the buckets to bezel plastic pieces shall be within 1.5 mm. The maximum

acceptable gap between LCD panel and bezel shall be within 2.5 mm.

8. Environmental

Operating Temperature 0°C to +40°C
Storage Temperature -20°C to +60°C
Operating Relative Humidity 65% non-condensing
Storage Relative Humidity 85% non-condensing
Operating Altitude 0 to +3,000 meters above sea level
Storage Altitude 0 to +12,000 meters above sea level

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3. Front Panel Function Control Description

Front View of the Product

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54321

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1

Volume Down

Decrease sound volume or adjust a highlighted control while in OSD menu.

Volume Up

2

Increase sound volume or adjust a highlighted control while in OSD menu.

Menu

3

urn OSD menu ON/OFF.

T

CH Down

4

hannel down when source is at TV or select a control while in OSD menu.

C

5

CH Up

Channel up when source is at

6

ENTER

o highlight a control in OSD menu.

T

Power ON/OFF button

7
8

Power LED Indicator / Remote Control Receiver

Note:

1. Press VOL+ and MENU buttons at the same time to lock power button, and press
VOL+ and MENU buttons again to unlock it.

2. Press VOL- and VOL+ buttons at the same time to lock OSD menu, and press
VOL- and VOL+ buttons again to unlock it.

TV or select a control while in OSD menu.

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Rear View of the Product

A
B

C
D

E

F

ENGLISH

O

A

RF Antenna / Cable TV Input

Connect to the antenna or cable service.

Composite Video Input

B

Connect other devices, such as DVD or VCD to this port.

C

YPbPr / HD Component Video Input

Connect the external video devices with component output to these jacks.

S-Video Input

D

Connect other devices, such as DVD or VCD to this port.

E

SCART1 Input

Connect other devices, such as DVD or VCD to this port.

SCART2 Input

F

Connect external devices, such as DVD or VCD to this port.

Audio Input for AV or S-Video

G

Connect external audio to this port.

Audio Input for YPbPr Components

H

Connect external audio to this port.

Audio Output

I

Connect external speaker into this jack.

PC Audio Input

J

Connect this port to PC line out jack.

Earphone Jack

K

VGA (15 pin) Signal Input

L

Connect to a computer.

HDMI Input Terminal

M

Connect this port to the HDMI output of A/V device.

Power Input (AC Input)

N

Connect to LCD TV and AC outlet with the power cord.

O

AC Power Switch (Must be turned on)

Without using for a period of time, turn the switch off.

N

M

JL K

G

H

I

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Remote Control

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ENGLISH

Note: PIP means Picture In Picture. POP means Picture Out Of Picture.

Remote control button function as follow

1 POWER Power ON/OFF

2

LED Power LED Indicator

3

MUTE Volume mute ON/OFF

4

SOURCE Select input source (for main screen)

5

INFO Display the current information

6

POP POP ON/OFF

7

PIP PIP ON/OFF

8

P. SOURCE Input source select (for PIP/POP sub-screen)

9

P. SIZE Adjust the size for PIP/POP sub-screen

10

V+ Adjust PIP/POP sub-screen’s volume increasingly

11

V- Adjust PIP/POP sub-screen’s volume decreasingly

12

P+ Select up program for PIP/POP sub-screen

13

P- Select down program for PIP/POP sub-screen

14

SWAP Swap main and sub screen of PIP/ POP

15

P. POS Adjust PIP/POP sub-screen’s position

16

RED Enter program name edit function

17

GREEN Add desired channels

18

YELLOW Erase desired channels

19

BLUE Confirm edited name

20

VOL UP/ DOWN Adjust volume up or down

21

SMART. S Select situation mode for sound

22

SMART. P Select situation mode for picture

23

PROGRAM UP/ DOWN Select up or down programs

24

MENU OSD menu ON/OFF

25

ASPECT Aspect ratio, used to select image size

26

UP/DOWN/LEFT/RIGHT Select or adjust the function of OSD

27

ENTER Confirm the selection

28

AVC The tuner contains automatic volume control circuitry (AVC)

to prevent converter overload

29

M S SOUND Sound select between main screen and sub-screen

30

0~9 NUMBER

Switch channel number buttons

31

SLEEP TV Sleep timer setup

32

FLASHBACK Return to previos channel

33

DUAL I / II MTS (Multi-Channel TV Sound) select

34

FREEZE Freeze picture

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ENGLISH

PIP/POP

PIP/POP button allows you to watch two screens from different sources at the same
time. (PIP is picture in picture; POP is picture out of picture)
Press PIP/POP on the remote control repeatedly.
The screen will change from normal screen → PIP screen → POP screen.

PIP Screen POP Screen

• PIP Input Source Select

1. Press P. SOURCE button to select input source for sub-screen as following.

Main Screen Available Sub-Screen Input Source

TV / AV / S-VIDEO / SCART1 / SCART2 /
SCART2-SVIDEO

D-SUB / HDMI / HD

D-SUB / HDMI / HD

TV / AV / S-VIDEO / SCART1 / SCART2 /
SCART2-SVIDEO

2. Press ENTER to confirm selection.

• SWAP
Press SWAP to exchange main-screen to sub-screen.

• PIP Size Select
Press P.SIZE to select the size of sub-screen. The function only acts on PIP.

• PIP Position Select
Press P.POS to select the position of sub-screen. The function only acts on PIP.

• Adjust Volume of Sub-screen
Press V+ and V- to adjust volume of sub-screen.

• Select Program for Sub-screen
Press P+ and P- to select the program of sub-screen.

Sound

• Sound Mode Select
Press SMART. S to select the sound mode between Movie, Music, Speech, and User.

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ENGLISH

OSD Functions

Picture Menu — Adjusting the picture

It is active in TV / AV / S-VIDEO / HD / SCART1 / SCART2 / SCART2-SVIDEO / HDMI
source.

• Contrast: To adjust contrast of video.

• Brightness: To adjust luminance of video.

• Colour: To adjust colour.

• Tint: To adjust tint level.

• Sharpness: To adjust picture sharpness.

• Fresh Tone: To adjust colour of skin.

• Colour Temp.: To select the screen colour temperature between Normal, Warm, and Cool.

Sound Menu — To adjust sound

It is active in all input sources.

• Source: To select the sound source from main screen or sub screen by pressing ◄►.

Note: It is available in SCART1/ SCART2/ SCART2-SVIDEO. However, in other input sources,
it is only active when in PIP/POP condition.

• Bass: To adjust bass (It is active in TV/ SCART1/ SCART2/ SCART2-SVIDEO. However,

in other input sources, it is only active when sound mode is in “User” condition).

• Treble: To adjust the treble (It is active in TV/ SCRT1/ SCART2/ SCART2-SVIDEO.

However, in other input sources, it is only active when sound mode is in “User” condition).

• Balance: To adjust left and right audio balance.

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Channel Menu — To setup for TV

It is only active in TV source.

• Auto Scan: To automatically preset the channels into TVs memory by pressing◄►. Kindly

suggest you auto scan all the channels before watching your TV for the first time.

Note: Auto Scan will scan twice. First scan for PAL system, and second scan for SECAM
system. After auto scan all the channels, you need not to do it again when turning on your
TV next time.

*China TV system: PAL D/K

• Manual Store: The function is to give a minute search for possible existing channels and

store them in memory.

ENGLISH

1. Press ◄ or ► to get into “Manual Store”.

2. Move the cursor to “Prog. No”, and select the desired channel position with ◄►.

3. Move the cursor to “System”, and select the system according to your local area with◄►.

4. Move your cursor to “Search”, and search the detectable channels with ◄►.

5. Move your cursor to “Fine Tune”, and adjust the picture with ◄►.

6. Move to Store, then store the instruction with ENTER .

Note: The channel will be stored instead of the former program.

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ENGLISH

• Name: To enter a name for program with 0~9, +-. /, and A~Z. Press ◄ or ► to get into “Name”.

1. To enter a name:

Press red button (on the remote control) to move your cursor to “Name”.
Use ▲▼ to select the desired letter and use◄► to move the cursor to enter next letter.
To confirm the name, press blue button.

2. To Erase/Add channels:

Use ▲▼ to select the desired channel.
Press yellow button to erase the channel or press green button to add it.
When using Program▲▼ button, the channels you erased will be passed over. You may
press green button to add the erased channels or use Auto Scan function to re-present
them.

• Sort: To exchange one channel with another. Press ◄ or ► to get into “Sort”.

If you want to exchange channel 1 with channel 2:

1. Move your cursor to “From,” and press ◄► to select channel 1.

2. Move your cursor to “To,” and press ◄► to select channel 2.

3. Move your cursor to “Store,” and confirm the instruction with

4. Press MENU to exit.

ENTER .

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Option Menu

When input source is TV/ AV/ S-VIDEO/
HD/ SCART1/ SCART2/ HDMI (HDCP)
SCART2-S-VIDEO:

When input source is D-SUB/ HDMI (PC):

• Main Source: To select the input source for main screen between TV, AV, S-VIDEO, HD,

SCART1, SCART2, SCART2-SVIDEO, D-SUB, and HDMI with ◄►.

• H-Position: To adjust the horizontal position of the video with ◄►.

• V-Position: To adjust the vertical position of the video with ◄►.

• Language: To select the OSD language between English, Simply Chinese and Traditional

Chinese with ◄►.

• Reset: Press ENTER to reset all the settings in All mode.

PC Menu — to adjust for PC

It is only active in D-SUB and HDMI (support PC mode).

When input source is D-SUB: When input source is HDMI (PC):

ENGLISH

• Auto Adjust: Auto adjust picture’s horizontal position, vertical position, fine tune, and

H-Size with ◄►.

• Contrast: To adjust foreground luminance of video.

• Brightness: To adjust background luminance of video.

• H-Position: To adjust horizontal position of video.

• V-Position: To adjust vertical position of video.

• Clock: To adjust delay time of clock in order to reduce the noise of picture.

• Phase: To adjust delay time of phase in order to reduce the noise of picture.

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ENGLISH

• Colour Mode: To adjust colour temperature.

1. Press ◄ or ► to get into Colour Mode.

2. Use ◄►to select between Cool, sRGB, User, Normal, and Warm.

3. When select “User”, it allows you separately adjust the colour of red, green, and blue.

OSD Menu — to setup OSD window

It is active in all input sources.

• H-Position: To adjust the OSD horizontal position with ◄►.

• V- Position: To adjust the OSD vertical position with ◄►.

• Duration: To automatically shut off the OSD after a preset period of time passed. Use ◄►

to preset the time from 5 to 60 seconds.

• Halftone: To adjust background transparency of OSD.

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4. Circuit Description

A. A/D converter (PC & YPbPr) and DVI(HDCP) input

The MST5151A-LF offers designers the flexibility of an analog interface and
High-Definition Multimedia Interface (DVI) receiver integrated on a single chip. Also
included is support for High bandwidth Digital Content Protection (HDCP).

Analog Interface

The MST5151A-LF is a complete 8-bit 165 MSPS monolithic analog interface optimized
for capturing Component Video (YPbPr) and RGB graphics signals. Its 165 MSPS encode rate
capability and full power analog bandwidth of 300 MHz supports all HDTV formats (up to
1080p) and FPD resolutions up to UXGA (1600 x 1200 @ 60 Hz). The analog interface
includes a 165 MHz triple ADC with internal 3.3V reference, a Phase Locked Loop (PLL),
and programmable gain, offset, and clamp control. The user provides only 1.8V and 3.3V
power supply, analog input, and Hsync. Three-state CMOS outputs may be powered from

1.8V to 3.3V. The MST5151A-LF on-chip PLL generates a pixel clock from Hsync. Pixel
clock output frequencies range from 12MHz to 165 MHz. PLL clock jitter is typically less
than 500 ps p-p at 165 MHz. The MST5151A-LF also offers full sync processing for
composite sync and Sync-on-Green (SOG) applications.

Digital Interface

The MST5151A-LF contains a DVI(HDCP) 1.0 compatible receiver and supports all
HDTV formats (up to 1080p) and display resolutions up to UXGA (1600 x 1200 @ 60 Hz).
The receiver features an intra-pair skew tolerance of up to one full clock cycle. With the
inclusion of HDCP, displays may now receive encrypted video content. The MST5151A-LF
allows for authentication of a video receiver, decryption of encoded data at the receiver, and
renew ability of that authentication during transmission as specified by the HDCP v1.1
protocol.

Fabricated in an advanced CMOS process, the MST5151A-LF is provided in a
space-saving 100-lead LQFP surface-mount Pb free plastic package and is specified over the 0

o

C to 70 oC temperature range.

B. V i deo Decoder (video)

The SAA7117 is a highly integrated NTSC, PAL, and SECAM video decoder support for
high quality LCD-TV video applications, SAA7117 supports NTSC/PAL chroma and luma
separation using a 2-dimensional adaptive comb filter for reducing the cross-luma and
cross-chroma artifacts. The frame buffer is also use for 2D noise reduction circuit that resumes
good visual quality when the input signal is a noisy video source

The SAA7117 10-bits CMOS Analog-to-Digital Converters(ADC) at four-fold ”ITU656”
oversampling(54MHZ);Sixteen analog input pins.allowing fo multiple combinations of
composite.S-Video component video;Eight 3-level capable sensor pins for D-connector or
SCART AV- and RGB- switch signals(three of those can be active simultaneously),one Fast
blanking input;Level sensitive fast blanking(RGB switch control);I²C read back of digital
AGC gain factor; The component, composite, or S-Video signals are sampled at a free-run
external clock frequency (10~58.6 MHz). After the video decoder processing, the video data
was sent out with a line-locked alignment rate (24.576 MHz).

The SAA7117 comes with 160-pin QFP package.

C. Scaling controller

The MST5151A-LF chip is a LCD-TV controller chip for color display up to SXGA or

/WXGA wide screen panel. It includes a 128/256/512 4-bit/fixel font 3D interlace-to
progressive video processing. It also supports non-linear scaling for 4:3 to/form 16:9
conversion, flexible picture in video display, cinema to TV conversion, hue/saturation
adjustment, and advanced OSD system.

The MST5151A-LF chip is targeted for the applications of high-end LCD-TV. It will

accept all HDTV video signals for flat panel display. It comes with 256-pin LQFP package.
General Feature:

 1M*32Bit*4Banks SDRAM controller for interlaced to progressive video processing and

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fram-rate conversion for computer graphics.

 PIP (picture in picture)/POP(picture on picture)
 MstarACE-2 picture/color processing and Embedded On-screen display controller(OSD)

engine

 Hardware mode detection for HDTV.
 Two sets of mode detection for flexible simultaneous main- picture and sub-picture

display.

 Copy protection detect and display enable.
 On chip hue, saturation, brightness, contrast, and gamma correction.
 Max pixel rate up to 135 MHz.
 Video Black White Expansion.
 Flesh tone adjustment.
 Improved temporal-spatial dithering.
 Non-linear scaling for 4:3 to/form 16:9 conversion.
 Auto cinema mode detection, 3:2/2:2 pull-down, and 3D de-interlacing.
 Desk and ceiling mode for projector application.
 PWM (Pulse Width Modulators) from 28K to 100Hz.

D. Audio

Three audio sources put into MSP 4410G which fist sel ect the sources and do pre-amplify. The
bass treble control also is provided. The control of all the functions is accomplished by serial
bus. Audio amplifier put into IC TI TPA3004D2 is a class-D amplifier that is output power of
20W/channel on a 12V power supply operation.

E. Tuner

The Antenna receive the TV signal and modulate it to the CVBS signal which can be
recognized by the decoder and FM-stereo/FM-mono/NICAM audio signal output to the sound
Automatic standard decoder IC MSP3410G. The MCU can automatic detect the tuner and send
order by serial bus.

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5. Adjusting Procedure

1. Function Test

1.1. Product

- 27” LCD TV

1.2. Test Equipment

-PC signal generator: CHROMA 2525 CARD ,CHROMA 2327 or 2329,Pioneer
DV-S969AVi.

-TV and Video signal generator.

-Color analyzer: MINOLTA CA110.

-Power meter: CP-310A or CP-320A.

-AC power supply transformer: 110V/120V ±20% 60Hz ±5%.

-Digital ammeter

1.3. Test Condition

Before function test and alignment, each LCD TV should be run-in and warmed up for at
least 30 minutes with the following conditions:
(a) In room temperature,
(b) With full-white screen, and 16 grey scale,
(c) With cycled display modes.

1.4. Test Display Modes & Pattern

1.4.1 EEPROM INIT
A. Timing: 1360*768@60Hz
B. Pattern: 16*12 grids
C. Press ’POWER’, ‘▲’and ‘ENTER’ at the same time, then go into the FACTORY

MODE.

Fig. 1 Fig. 2

D As shown in Fig. 1, press “ENTER” key and Fig.2 will show. After “EEPROM

INIT” disappears, the procedure of “EEPROM INITIAL” is completed, and the OSD
moves to “WHITE BALANCE”.

1.4.2 COLOR TEMPERATURE ADJUSTING
PC MODE:

A. Timing: 1360*768@60Hz.
B. Pattern: 16 gray-scale and all-white screen.
C. Confirm that the TV uses BURN IN screen and the warm-up time lasts over 30

minutes.

D. How to enter/exit BURN IN mode:First, enter Factory mode OSD (refer to

previous instruction), move the cursor to the column of BURN IN, press
“ENTER” key to switch to ON, press ”POWER” key to restart the TV, and then
press ”ENTER” key to enter BURN IN mode. To exit BURN IN mode, repeat the
procedure again, but switch the column of BURN IN to “OFF”.

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E. Confirm that the distance between the SENSOR of CA110 color temperature

meter and the central point of the machine is 20cm.

COLOR TEMPERATURE OSD

Fig.3 Fig.4

When in the 16 gray-scale screen, the cursor will point to “WHITE BALANCE”, as shown in
Fig.3. Press “ENTER” key to start temperature adjustment automatically, as shown in Fig.4.
After “WHITE BALANCE” disappears, the performing of “WHITE BALANCE” is
completed.After the adjustment is done, switch to an all-white screen to confirm the
chromaticity coordinate value.

Preset color for N2750w (2G)

Normal ---- 9300 x=0.285 ±0.015 y=0.293±0.015
Warm ---- 6500 x=0.313 ±0.015 y=0.329±0.015

COOL ----- 12000 x=0.271 ±0.015 y=0.278±0.015

1.4.3 COLOR TEMPERATURE ADJUSTING

HD MODE:

Timing: PAL OR NTSC

A.

Pattern: Color bar

B.
When in the color bar screen, the cursor will point to “WHITE BALANCE”, as shown in
Fig.3. After “WHITE BALANCE” disappears, the performing of “WHITE BALANCE” is
completed.

Normal ---- 9300 x=0.285 ±0.015 y=0.293±0.015

Warm ---- 6500 x=0.313 ±0.015 y=0.329±0.015

COOL ----- 12000 x=0.271±0.015 y=0.278±0.015

1.4.4 POWER SAVING TEST

A. Timing: 640 × 480 @ 75Hz
B. Pattern: TEST-TTL/ECL

C. Set BRIGHTNESS and CONTRAST to the maximum
D. The power dissipation for each mode is as follows

MODE Maximum Power

NORMAL <150W GREEN

Standby < 5 W Orange

OFF < 5 W Orange

1.4.5 Confirm HDMI MODE TIMING
A. In DVI MODE, switch TIMING according to the FACTORY PRESET TIMING

TABLE, and confirm that the screen is normal
B. Confirm that the four TIMING screens of 408i, 480P, 720P, and 1080i are normal
C. Confirm that HDMI DVD functions normally

POWER LED COLOR

Dissipation

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1.4.6 Confirm OSD Function Performing
A. Timing: 640 × 480 @ 75Hz
B. Pattern: “GENERAL-1
C. Confirm that each function in the OSD works
D. After the confirmation is completed, the default setting of EEPROM INITIAL

AND WHITE BALANCE must be restored before shipping

1.4.7 DTV FUNCTION TEST
A. Select input source to DTV, Fig.3 will be shown.

Fig.3

1.4.8 YPbPr, S-VIDEO, AV, TV, DTV’S FUNCTION TEST
A. Input YPbPr, S-VIDEO, AV , TV, DTV’S signal and check.
B. Input USA air channel (TABLE 1) and USA CATV channel for TV channel.
C. Under YPbPr MODE, Make sure the 408i, 480P, 720P, 1080i is right.

1.4.9 AUDIO FUNCTION TEST

A. Audio input includes PC AUDIO IN, S-VIDEO/AV AUDIO IN and YPbPr AUDIO

IN.

B. Under PC MODE, input PC AUDIO signal, checks whether the action of AUDIO

IN is right.

C. Under S-VIDEO/AV MODE, input L/R AUDIO signal, checks whether the action

of AUDIO IN is right.

D. Under YPbPr MODE, input L/R AUDIO signal, checks whether the action of

AUDIO IN is right.
E. Under HDMI MODE, checks whether the action of AUDIO IN is right.
F. Under DTV MODE, checks whether the action of SPDIF is right.
G. AUDIO OUT FUNCTION TEST: Under all patterns except PC pattern, The Audio

output meets active extra speaker, examines whether the extra speaker makes the

sound.

1.4.10 EARPHONE FUNCTION TEST
Under PC MODE, input PC AUDIO signal, determines whether the action of INT
SPEAKER output is right. Meets earphone with the EARPHONE, Determined
whether the action of EARPHONE output is normal.

1.4.11.TV RECEIVING TEST:

A. Examines sound by ear, whether the sound does have mechanical resonation and

the electrical unusual sound, and image to sound disturbance.

B. Examines whether the sound does receive the image disturbance, Judgment basis:

Whether there is unusual sound, input signal LEVEL<=36dBu,and STEREO
SENSITIVITY is normal.

C. Adjustment attenuator, If the critical point of the change of the image signal to

noise ratio is under LEVEL<=60dBu,regards as normally.

D. Examines TV brightness; confirm whether DUAL FUNCTION is normal under

DUAL MODE: whether DUAL SENSITIVITY is normal when input signal is
under LEVEL<=36dBu.

E. Examines whether PAL color demodulation is normal by using DEM image;

whether STEREO SENSITIVITY is normal when input signal is under
LEVEL<=36dBu.

F. Examines whether DUAL FUNCTION is normal under DUAL MODE; whether

DUAL SENSITIVITY is normal when input signal is under LEVEL<=36dBu.

G. Examines whether the sound does receive the image disturbance, Judgment basis:

Whether there is unusual sound, input signal LEVEL<=36dBu,and STEREO

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SENSITIVITY is normal.

H. Adjustment attenuator, If the critical point of the change of the image signal to

noise ratio is under LEVEL<=60dBu,regards as normally.

1.4.12.VIDEO RECEIVING TEST:

AV receives supply oscillator: AV/S-Video/HD/SCART1/SCART2/SCART-SV are

from DVD to LCD TV; Examines whether has the image and the sound and is

normal.
A. AV: Video cable (Yellow), Audio cable (Left (White), Right (Red) sound track).
B. S-Video: S-Video signal cable (White), Audio cable (Left (White), Right (Red)

sound track).

C. HD (Ypbpr/YcbCr): brightness signal cable (Green), Component signal cable (Red,

Blue), Audio cable (Left (White), Right (Red) sound track).
D. SCART1: 21Pin SCART signal cable (Black).
E. SCART2: 21Pin SCART signal cable (Black).

1.4.13.VIDEO/AUDIO OUTPUT TEST:
A. SCART/AV output: A 27” LCD TV in AV pattern, inputs the CVBS signal; the

output meets SCART, SCART connects another 27” LCD TV which is in SCART
pattern, Examines two 27” LCD TV whether demonstrates the same image. But
their sound doesn’t mutually affect, Must respectively adjust volume to examine
sound. AV output test method is in the same way.

B. Under any pattern except PC pattern, The Audio output meets active extra speaker,

examines whether the extra speaker makes the sound.

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