LG LQ800 Service Manual

1. LCD CHARACTERISTICS

Type : Color Active Matrix TFT LCD Size : 18.1inch (45.97cm) Pixel Pitch : 0.2805mm x 0.2805mm Pixel Format : 1280 x 1024 pixels

RGB Stripe Arrangement Color Depth : 8-bit, 16 million colors Active Video Area : 413mm x 333mm Surface Treatment : Anti-Glare, Hard Coating (3H) Backlight Unit : 4 - CCFL (Cold Cathode

Fluorescent Lamp)

2. OPTICAL CHARACTERISTICS

2-1. Viewing Angle by Contrast Ratio

³

10 Left : 70¡ typ., 70¡ min. Right : 70¡ typ., 70¡ min. Top : 45¡ typ., 45¡ min. Bottom : 45¡ typ., 45¡ min.

2-2. Luminance : 160 or 165 cd/m

2

typ.

2-3. Angle at Half Luminance

Left : 70¡ min. Right : 70¡ min. Top : 45¡ min. Bottom : 45¡ min.

2-4. Contrast Ratio : 150¡ typ.

3. SIGNAL (Refer to the Timing Chart)

3-1. Sync Signal

1) Type : Separate Sync. (Horizontal & Vertical)

2) Input Voltage Level : Low=0~0.8V, High=2.1~5.5V

3) Sync Polarity : Positive or Negative

3-2. Video Input Signal

1) Type : R, G, B Analog

2) Voltage Level : 0~0.714 V a) Color 0, 0 : 0 Vp-p b) Color 7, 0 : 0.467 Vp-p c) Color 15, 0 : 0.714 Vp-p

3) Input Impedance : 75 ½

3-3. Operating Frequency

Horizontal : 31 ~ 80kHz Vertical : 58 ~ 85Hz

4. POWER SUPPLY

4-1. Power Adaptor

Input : AC 100~240V, 50/60Hz 1.2A Output : DC 12V 5.0A

4-2. Power Consumption

5. ENVIRONMENT

5-1. Operating Temperature: 10¡C~30¡C (50¡F~95¡F)

(Ambient)

5-2. Relative Humidity : 10%~80%

(Non-condensing)

5-3. Altitude : 0~10,000ft (3,030m)

6. DIMENSIONS (with TILT/SWIVEL)

Width : 432.0mm (17.01'') Depth : 247.1mm (9.73'') Height : 446.6mm (17.58'')

7. WEIGHT (with TILT/SWIVEL)

Net Weight : 9.2kg (20.28 lbs) Gross Weight : 12.9kg (28.44 lbs)

- 2 -

MODE

POWER ON (NORMAL)

STAND-BY

SUSPEND

Sleep Timer Function

Active

POWER OFF

H/V SYNC

ON/ON

OFF/ON

ON/OFF

ON/ON

-

POWER CONSUMPTION

less than 60 W

less than 5 W

LED COLOR

GREEN

ORANGE

Orange Flashing

at 0.5Hz

OFF

VIDEO

ACTIVE

OFF

ON

-

SPECIFICATIONS

-

+

- 4 -

VIDEO

SYNC

D

F

B

E

A

TIMING CHART

MODE

Resolution

H

O

R

I

Z

O

N

T

A

L

V

E

R

T

I

C

A

L

kHz

Pixels

Hz

Lines

+

25.175

31.469

800

640

16

96

48

-

70.8

449

350

38

2

59

MARK

E

A

B

D

F

E

A

B

D

F

Sync Polarity

Dot Clock

Frequency

Total Period

Video Active Time

Front Porch

Sync Duration

Back Porch

Sync Polarity

Frequency

Total Period

Video Active Time

Front Porch

Sync Duration

Back Porch

FACTORY PRESET MODE

640

X

350

71Hz

-

28.321

31.468

900

720

18

108

54

+

70.8

449

400

12

2

35

720

X

400

71Hz

-

25.175

31.469

800

640

16

96

48

-

59.94

525

480

10

2

33

640

X

480

60Hz

+

56.25

53.674

1048

800

32

64

152

+

85.061

631

600

1

3

27

800

X

600

85Hz

+

94.5

68.677

1376

1024

48

96

208

+

84.997

808

768

1

3

36

1024

X

768

85Hz

+/

-

100.0

68.681

1456

1152

32

128

144

+/

-

75.062

915

870

3

39

1152

X

870

75Hz

+/

-

92.978

61.805

1504

1152

18

134

200

+/

-

65.96

937

900

2

4

31

1152

X

900

65Hz

+

108.0

63.981

1688

1280

48

112

248

+

65.02

1066

1024

1

3

38

1280

X

1024

65Hz

+

135.0

79.976

1688

1280

16

144

248

+

75.035

1066

1024

1

3

38

1280

X

1024

75Hz

-

31.5

37.50

840

640

16

64

120

-

75.0

500

480

1

3

16

640

X

480

75Hz

-

36.0

43.269

832

640

56

80

-

85.0

509

480

1

3

25

640

X

480

85Hz

+

40.0

37.879

1056

800

40

128

88

+

60.32

628

600

1

4

23

800

X

600

60Hz

+

49.5

46.875

1056

800

16

80

160

+

75.0

625

600

1

3

21

800

X

600

75Hz

+/

-

57.283

49.725

1152

832

32

64

224

+/

-

74.55

667

624

1

3

39

832

X

624

75Hz

-

65.0

48.363

1344

1024

24

136

160

-

60.0

806

768

3

6

29

1024

X

768

60Hz

-

78.75

60.123

1312

1024

16

96

176

-

75.03

800

768

1

3

28

1024

X

768

75Hz

MODE1MODE2MODE3MODE4MODE5MODE6MODE7MODE8MODE9MODE10MODE11MODE12MODE13MODE14MODE15MODE

16

MHz

- 8 -

CONTROL LOCATIONS

1234

5

NO.

1

2

3

4

5

Ref. No.

SL-SW

SW01

SW02

SW03

SW04

Control Function

SLIDE SWITCH

MENU BUTTON

-

BUTTON

+ BUTTON

POWER SWITCH

- 8 -

WIRING DIAGRAM

J07

J04

J1J2

J3J4

J5

CN2

J05 J06

P02

P01P02

CN1

DISASSEMBLY

- 9 -

1. TILT/SWIVEL REMOVAL

Remove Hinge Cover (Push the tilt cover both side). Remove two screws Remove the Tilt/swivel.

2. FRONT CABINET REMOVAL

Remove two screws cap . Remove two screws . Release ten latches . Remove the Front Cabinet.

3. INVERTER WIRE SHIELD & BACK COVER REMOVAL

Remove four screws . Remove two Inverter Wire Shield. Remove five screws . Remove the Back Cover.

4. LCD MODULE REMOVAL

Remove four Aluminum Tapes . Disconnect J1, J2, J3 and J4. Disconnect FPC Cable and Module Power Connector

.

Remove the LCD Module.

Front Cabinet

Inverter Wire Shield

Back Cover

- 10 -

6. INVERTER FRAME & REAR SHIELD REMOVAL

Remove two screws . Release two latches . Remove the Inverter Shield. Remove six screws . Remove the Rear Shield.

5. BACKLIGHT REMOVAL

Remove two screws . Remove the Backlight from the LCD Module.

7. MAIN FRAME REMOVAL

Remove four screws . Remove screw . Remove two fixers . Divide the Main PCB AssÕy.

8. MAIN TOTAL ASSÕY REMOVAL

Disconnect J5 and J06. Remove Inverter AssÕy and Control PCB from the Main PCB. Release two latches . Divide Top Shield, Main PCB, and Bottom Shield.

Bottom (Lower) Backlight AssÕy

Top (Upper) Backlight AssÕy

Rear Frame

Inverter Frame

Main Frame

Inverter PCB

Main PCB

AssÕy

PCB Shield

(Bottom)

Control PCB

Inverter AssÕy

Main PCB

PCB Shield

(Top)

EXPLODED VIEW

2

3

4

5

6

7

8

9

10

11

12

14

a

b

c

d

e

5-1

5-2

5-3

14-1

13

1

a

15

16

EXPLODED VIEW PARTS LIST

Ref. No.

1

2

3

4

5

5-1

5-2

5-3

6

7

8

9

10

11

12

13

14

14-1

15

16

a

b

c

d

e

Part No.

3091TKL004A

3091TKL004B

6304TLT181A

4814TKK064A

4951TKS034A

3313TL8001A

4950TKK049A

6871TMT077A

4950TKK048D

6633TZA002A

4814TKK067A

4950TKS097A

6871TST084A

6871TST089A

3809TKL004A

3809TKL004B

6634TBZ002A

6634TBZ002B

3550TKK044A

3550TKK044B

3043TKK034A

3043TKK034B

6871TST081A

3550TKK046B

4819TKK082A

332-015E

4930TKK014A

332-110A

332-095C

332-105F

Description

CABINET ASSÕY, OPAL COMPAQ LCD 18.1Ó

CABINET ASSÕY, CARBON BLACK COMPAQ LCD 18.1Ó

LCD MODULE, LGE TFT LCD LM181E1 18.1Ó

INVERTER WIRE SHIELD

METAL, MAIN FRAME

MAIN TOTAL ASSÕY

PCB SHIELD (BOTTOM)

MAIN PCB ASSÕY

PCB SHIELD (TOP)

INVERTER ASSÕY

INVERTER SHIELD

METAL, REAR FRAME

KEY CONTROL PCB ASSÕY

S/W PCB ASSÕY

BACK COVER ASSÕY, OPAL

BACK COVER ASSÕY, CABON BLACK

ADAPTER, AC-DC, 100/240V 12V 5A, OPAL

ADAPTER, AC-DC, 100/240V 12V 5A, CABON BLACK

HINGE COVER, OPAL

HINGE COVER, CABON BLACK

TILT SWIVEL ASSÕY, OPAL

TILT SWIVEL ASSÕY, CABON BLACK

USB PCB ASSÕY

PROTECTIVE PANEL COVER - PROTECTIVE MODEL ONLY

BRACKET, SUPPORT MODULE - NON PROTECTIVE MODEL

SCREW, PVS+3x16 (MSWR/FZMW)

HOLDER, FIXER

SCREW, PZS+3x6 (MSWR/FZMY)

SCREW, PZP+3x12 (MSWR/FZMY)

SCREW, PVS+4x10 (MSWR/FZMW)

Q'ty

1

2

1

4

2

13

7

2

Material

BLOCK DIAGRAM

- 11 -

POWER CORD

15-pin D-SUB SIGNAL CABLE

POWER

SUPPLY

CONTROL PCB

INVERTER PCB

MAIN LOGIC

PCB

LCD MODULE

System Block Diagram

BLOCK DIAGRAM

- 12 -

Data

Clock

Memory

Flat panel Controller

Display

Data

Transmitter

LCD

Module

KM416S102BT

MX88272

BA7657F

TDA4885

LVDS83

LM181E1

MCLK

H

V

5V

3.3V 5V 3.3V 3.3V

5V

3.3V

8V

12V

5V

Even

DS

H-Sync

CLK

. Contrast

Odd

CLAMP

SDA/SCL

CS/SDA/SCL

D-F/F

TT'L

Gate

Power

12V

Input Switch

Pre-Amp.

Inverter

Clock

Generator

DC/DC

Converter

AD9483

ICS1522

MAX785

A/D Converter

Micro-

Controller

Input Port "A"

Input Port "B"

. Brightness

Block Diagram for Main Logic Board

DESCRIPTION OF BLOCK DIAGRAM

1. Video Control Circuit

1) TDA4885 (U101) receives the video signal from PC and amplifies the levels of video signal (0V~0.7V), and controls the contrast signal.

2) The biases of A/D inputs control the reference output voltages of TDA4885 (U101) to proper R, G, B bias levels through the Diodes (D101, D102, D103).

4) The EX-OR (U604) device outputs the voltage levels to decide the polarities of HSYNCIN and VSYNCIN that supply the sync signals to the PLL IC and MICOM.

2. A/D Converter Circuit

1) AD9483 (U201) converts from the analog video signal to the digital signal. For this function, its DC 2.5V output is connected to VREF_IN and it samples the input signal between 2.0V~3.0V. (The reference voltage of the sampling is 2.5V.)

2) The frequency range of 8-bit digital output is from

12.5MHz to 67.5MHz with respect to modes.

3) The status of power down pin is low for normal state and high for power down state.

3. Features of ICS1522 PLL IC

1) ICS1522 (U11) generates the pixel clock for each mode with respect to internal register setting, which is used to sampling circuitry. The range of the pixel clock is approximately from 25MHz to 135MHz

4. Video Process Circuit

This circuit consists of MXIC (U501) and frame memorys (U401, 402, 403) which convert frame date of input signal to 60Hz frame date. This function is processed by MX88272. The MX88272 (U501) gets the video signal converted analog to digital, interpolates input to 1280x1024 resolution signal and outputs 8-bit R, G, B, DHS, DVS and DE signals to the transmitter (U701, U702).

5. LVDS Circuit

LVDS transmitter (U701, U702) delivers digital signal to the receiver of module by the voltage swing of 1V. The peripheral circuitry of transmitter gets the DHS, DVS, DEN, DISPCLK signal, outputs LVDS signal. At the power down mode, MICOM lets the power down signal be low and Shuton pin be active low.

6. Input Switching Circuit

This circuit consists of BA7657F (U601), slide switch and TTL gates. BA7657F (U601) switch analog R, G, B signal to be entered form 15p D-SUB A(J2) or B(J3). If the position of slide switch is A; R, G, B signal and H/V Sync are entered from D-SUB A. If the Position of slide switch is B; R, G, B signal and H/V sync are entered from D-SUB B. If the position of slide switch is Auto; R, G, B signal and H/V sync are automatically selected A or B by control signal of MICOM. But if A and B are incidentally connected, system display OSD, Ò2 Input active... select A or BÓ. TTL gates (U602, U603, U604) switch H/V sync to be entered from D-SUB A or B.

7. DC/DC Converter

This curcuit supplies stand-by 5V (5VST) that is made using IC U801 regulator for MICOM and SYNC processing. The 5VDD voltage is converted using MAX785 (U802) and supply to IC need to it. The 8VA is converted using 8V regulator (U808) and supply to video pre-amp. The 3.3V voltage is converted using 6 Diodes and supply to IC need to it. The 5VA is converted using 5V regulator (U809) and supply to A/D converter and PLL IC. The state of power down make all voltage except 5VST down using SHDN.

8. System Controller (08XL36) Circuit

This curcuit consists of EEPROM IC (U902) which stores control data, RESET IC (U904) and LED driver Q01 and Q02 indicate that power is ON or OFF.

The operating procedures of MICOM and its associated circuit are as follows:

- 13 -

1) The MICOM distinguishes polarity and frequency of the horizontal sync and the vertical sync are supplied from signal cable. The controlled data of each mode is stored in EEPROM.

2) User can adjust screen condition by each OSD function. (H-Position, V-Position, Clock, Clock Phase, ... etc.)

9. DDC Circuit

This circuit consists of MICOM (U901) and bidirection switching IC (U2).

1) Bidirection switching IC switch I

2

C line for DDC

communication by control signal of MICOM (U901).

2) The MICOM has D-SCL, D-SDA line for sending and receiving data to adjust line through 15-pin D-sub connector.

3) The data of EDID DDC information is stored in EEPROM IC (U902).

10. OSD Control Circuit

When the MX88272 outputs the area which is able to display overlay using OSDBLNK PIN of MX88272. OSD (On-Screen-Display) device (U502) outputs display data as the timing of the signal.

11. Power Module Circuit

This block supplies the +12V to the inverter for the backlight voltage of module and the +5V for data control of LCD module. That is, SI4925DY (Q01) is switched by TR Q12 for module voltage.

- 14 -