Beko Chassis L5A Schematic

L5A TFT- LCD TV

SERVICE MANUAL

CONTENTS

PAGES

Safety instructions

Technical specifications

Panel Specification

Chassis block diagram

Scaler block diagram

Block diagram of power supply

Chassis overwiev

Service mode items and explanations

Data sheet of important IC’s

Recommended 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.

L5A TECHNICAL SPECIFICATION

Receiving System

Comb Filter Adaptive 4H\2H

Scaling Upto SXGA at 75Hz

Gamma Correction 8 to 10-bit LUT

Histogram Equalization YES

Stereo Decoding (German A2, Nicam, BTSC)

Stereo L, R In 3

Stereo L, R Out 3

Audio Output Power RMS in Max at 10% THD) 2x3W, 2x5W for 22"W

Level (1.5, 2.5, Teleweb) Teletext 1.5

Teletext

WSS +

VPS\PDC +

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

WSS (Wide Screen Signalling) +

ATS (Automatic Tuning System) Frequency Search

Manual Search Channel Table Search

Number of Program Storage 100

No Ident Timer +

Picture Freeze +

Equalizer +

Zapping +

AVL (Automatic Volume Level) +

Sound Status Memory +

Picture Status Memory +

Swap +

Child Lock +

Program Lock +

Picture Format Switching Thru Pin 8 +

Auto RGB Detect Thru Pin 16 +

PC Plug & Play (DDC\CI) +

Timer

Picture Smart (User, Soft, Natural, Rich) +

Sound Smart (User, Music, Sports, Cinema, Speech)

Scart 2

S-video (DIN) 1

AV In (3 RCA) 1

AV Out (3 RCA) 1 (ONLY L, R)

D-Sub 15 1

Headphone 1

CVBS In 3

Y\C In 1

RGB+FB -Video 1

RGB+HS, VS In -Graphics 1

CVBS Out 2

Type (Fast\Top\Simple) Simple, Fast, Top

Page Memory 250p or 10p

4:3 +

16:9 +

Panorama +

Letterbox +

Subtitle +

Off Timer (Sleep Timer) +

On Timer +

PAL B/G+I+D/K SECAM L/L'

German A2, Nicam

Manufacturer

PANEL SPECIFICATION

14" 15" 17" 17W" 20" 22W" 23W"

Samsung

AUO

Hannstar CMO AUO Sanyo

Samsung Samsung

CMO AUO

Samsung

Interface

Resolution

Brightness (cd/m2)>

Contrast>

Response Time (Tr+Tf) msec <

Viewing Angle R\L\H\L >

Adaptor Input

Power consumptions

St-By Power Consumption

Input Range

Single LVDS

VGA (640x480) XGA (1024x768) SXGA (1280x1024) WXGA (1280x768)

450 250 300 400 500 450 450

500 300 400 400 500 500 400

25 35 25 25 16 25 25

85/85/85/85 60/60/40/50 70\70\60\60 70/70 50/60 80\80\60\60 85/85 85/85 85/85 85/85

Double TTL\Single LVDS

Dual LVDS Single LVDS

Single TTL\Single LVDS

SVGA (800x600) VGA (640x480)

Single LVDS Single LVDS

WXGA (1280x720) WXGA (1280x768)

12V 12V 12V 12V 15V 15V 24V

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

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

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

BLOCK DIAGRAM OF MAIN CHASSIS (L5A

)

Tuner IF

CVBS-IF

EEPROM 24LC16

SVHS-Y/C

HS/VS

K6T1008V2E

(Optional)

YUV

HS/VS

SRAM

AUDIO DECODER

Video Decoder

VPC 3230D

RGB

Teletext Decoder

SDA 5550

R MSP3410G

SC1-RGB

M29W040

Flash

Memory

HS/VS

Scaler

Stage

RGB

VGA-IN

TDA1571

Stereo

Amplifier

TDA1308

Headphone

Amplifier

PANEL

HS/VS

EEPROM

24LC02

SIF/AM-mono

Scart 1

Scart 2

SVHS/FAV

BLOCK DIAGRAM OF SCALER

HS/VS

RGB

VGA_RGB

VGA HS/VS

BAC LIGHT UNIT

S508 (LVDS) S500(TTL)

BR1_ADJ BLK_EN

GM 5221 U500

CONTROLLER

U501

PARALEL

FLASH

MEMORY

M29W040B

(OPTIONAL)

SERIAL FLASH

Panel_En Standby Mute Reset

LCD

U503

MEMORY

M25P40

KEYBOARD

CON. S509

S506

CONN.

LVDS

CONNECTOR

(20 OR 30 PINS)

(S503,S502)

DAUGHTER

BOARD

FOR TTL

INTERFACES

N E L

S505

PROGRAMING

CON

U502

EEPROM

24C16

L5A POWER SUPPLY BLOCK DIAGRAM

S600

DC Jack +15V-STBY

S602

V-INV

F600 15V,12V

Fuse

F601

LM2576

V-INV

U600

LM2576

U607

78L08

U606

+5V-STBY

+8V

LM1117

3.3V

LM1117

1.8V

U605

INPUT: 12V FOR 14,15,17 INCH 5V-STBY

15V FOR 20, 22 INCH 24V FOR 23 INCH

78L12

U608

+ 12V

3.3V-STBY

1.8V-STBY

+12V

+5V

U602

SDI9933ADY

LM117-3.3V

U604

Panel Power

ONLY FOR 23 "

ONLY FOR 20, 22, 23 "

78L08

U606

+8V

PNL-EN Power STBY

2.5V

3.3V

L5-A Low-to-Mid End LCD-TV BOARD OVERVIEW

L5-A Low-to-Mid End LCD TV board incorporates the LCD Controller gm2221, to create a high quality, stand-alone LCD-based TV system for consumer applications. Figure 1 illustrates the Block diagram of the board.

This board supposed to have two versions:

1. Low-End (to drive 14''-15’’ 4:3 panels)

2. Mid-End (to drive 17’’-20’’ 4:3 and 17’’-22’’-23'' 16:9 panels)

LOW TO MID END LCD TV WITH GM2221

RGB, HS, VS

Selected

Video

EDID VGA

ITU 656

8-bit

FLASH

SDRAM

GM2221

ADC+PLL

ITU 656

De-interlace

Scaling

MCU X86

OSD(4bit\pixel)

2 LVDS Tx

QSS

Ext L/R

L/R

TDA1308T

FLASH

NVRAM

1p, 2p\clk

LVDS

24-bit TTL

HS, VS, DE

Upto SXGA at 75Hz

Audio

Decoder

MSP 3410G

AudioAmp TDA1517P

L R

15", 17",

20'' 4:3

17''

22'' 16:9 TFT

LCD

Main

L/R

3.3V 2.5V

Step Down & Lineer Regulators

12V

QSS

Multimedia

Tuner

EXT. CVBS, S-video

Scart RGB, FB

1.8V

CVBS

Graphics

Upto SXGA at 75Hz

UXGA at 60Hz

SDA,SCL

Chroma

Decoder

VPC 3230D

RGB, FB

Teletext

Decoder +MCU

SDA5550

Figure 1 System Block Diagram

L5-A board supports 5 types of video and graphics inputs. These inputs are: Analog terrestrial tuner input for multisystem PAL/SECAM transmission, SCART input (x2), S-VHS input, RCA input and analog PC video input.

The analog RGB signals coming from the PC input (via D-Sub15 connector P401) are directly connected to the gm2221 analog input port.

One EDID IC (U400) is provided on board to support VESA standard plug-and play compatibility.

On the board, one high quality video decoder (U100) is provided (VPC3230D of Micronas) to process video inputs coming from the video sources. The video processor can process 3 composite video inputs and 1 S-Cideo input from the NTSC/PAL video sources. The CVBS output recovered from the tuner module is made available to one of the video inputs of the video decoder.

The digitized video output (in ITU-656 format) from U100 is fed to the dedicated video Port of gm2221 for decoding and processing.

Gm2221 makes it possible to perform scaling and de-interlacing for the video input.

A 4Mbit serial flash ROM (U503) is used for storing system firmware. Also the footprint for a parallel flash ROM, which can be upto 2Mbits, is available on the board. This option can be used either for development or for production purposes.

The gm2221 provides direct connect via the integrated LVDS transmitters to LCD panels with integrated LVDS receivers. Both single LVDS (via S503) and double LVDS(via S502) panels can be supported directly from the L5-A main-board. For single LVDS panels, only S503 connector is soldered on the main-board, which is a 20 pin connector. For Double LVDS panels, only S502 connector is soldered on the main-board, which is a 30 pin connector. For supporting different LVDS panels, different LVDS cables (either single or double LVDS) can be made used.

For supporting different single or double TTL panels, a daughter board interface is used via 40 pin S506 connector. On this connector, the signals are 3x8bit RGB with TTL control signals (i.e. HSync, VSync, CLK, O/E etc.) to support a wide variety of LCD panels. Depending on the panel used, different daughter boards will be used to support that particular panel. For single TTL panels, the daughter board will just be a routing the RGB and control signals to the particular connector interface for that particular panel. For double TTL panels, there will be two LVDS receiver IC’s on the daughter board (double TTL is not directly from GM2221 but double LVDS is supporter due to IC packaging problems) to demodulate double LVDS signal into double TTL signal.

The LCD panel resolution supported can be up to SXGA at 75 Hz or UXGA at 60 Hz.

It is important to note that at any point in time gm2221 could drive only one type of Panel. When LVDS Panel is connected (to connector S503 or S502) ensure that the panel backlight is connected to S508. The integrated PWM output from gm2221 is used to control the LCD panel backlight intensity for dimming functions.

The on screen display is implemented using OSD capability of gm2221. Infra Remote (IR) controller connector (S507) is provided as a primary control interface for connecting IR detector to the GPIO of gm2221. An IR remote controller unit and detector provide remote OSD menu access at user convenience.

A keypad connector (S507) is provided which utilizes the integrated low bandwidth ADC in gm2221 for scanning 5-6 keys (menu,V+,V-,P+,P- keys standard- source key optional) on the keypad. The keypad allows access to the OSD without using the remote IR controller.

The L5-A board also has In System Programming (ISP) capability for the external flash ROM using DDC2Bi. This can be done using the D-Sub 15 (PC) connector on the board. ISP can also be performed using G-probe through the RS232 interface.

One channel of the dual channel FET power switch (U602) is used to control the power sequencing to the LCD panel. Depending on the type of the panel, the input voltage to this FET device can be chosen as shown below:

For +3.3V panels J601 is soldered on the main-board For +5V panels J600 is soldered on the main-board For +12V panels J603 is soldered on the main-board

An LM2576, a step-down regulator IC (U600), is used to generate the main +5V_STBY voltage on the board. This IC can deliver up-to 3 Ampers of 5Volts. There is no stand-by control for this regulator, which means this IC is always on, as soon as power is supplied to the board.

U603(+3.3V_STBY) and U605 (+1.8V_STBY) linear regulators are used to supply the voltage necessary for the GM2221 IC and some peripherals. These voltages are also available in stand-by mode to power the microprocessor inside gm2221, LED, IR receiver IC and EEPROM. These devices are necessary to wake up the board from stand-by state.

Second channel of the dual channel FET power switch (U602) is used to control cut some voltages in stand-by mode. These voltages are +5V, +3.3V and +2.5V. These voltages are used by the video processor (VPC 3230D), audio processor (MSP 34x0G), teletext processor (SDA5550), tuner and some peripheral IC’s and circuitry. In order to limit the stand-by power consumption, these voltages are not available in stand-by mode. Also the audio amplifier (TDA1517) is also in its stand-by mode using its dedicated stand-by pin.

The board employs MSP3410G, a multi-system audio processor solution from Micronas. The system supports 4 audio input ports, one of which is not used on the L5-A board. Audio output is provided with speaker and headphone jacks (S409, S401) provided on the board. The sound IF signal from the tuner is connected to the audio processor directly.

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