LG 568LM, LM568E-GT Full

AUTO

VOL

MUTE MENU

SET

COLOR MONIT OR

SER VICE MANUAL

Website:http://biz.LGservice.com

E-mail:http://www.LGEservice.com/techsup.html

CAUTION

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

CHASSIS NO. : CL-18
F ACTORY MODEL: LM568E

MODEL: LCD 568LM (LM568E-GT)

*( ) ID LABEL MODEL No.

*To apply the Toshiba Module +GmZan2 Chip.

CONTENTS

SPECIFICATIONS

- 2 -

1. LCD CHARACTERISTICS

Type : Color TFT LCD
Size : 15.0 inch (38.1cm)
Pixel Pitch : 0.297mm x 0.297mm
Electrical Interface : LVDS Interface
Color Depth : 6-bits/ 16,194,277colors
Active Video Area : 304.1mm x 228.1mm
Surface Treatment : Anti-Glare, Hard Coating (3H)
Backlight Unit : Bottom edge side 2CCFL

(Cold Cathode Fluorescent Lamp)

2. OPTICAL CHARACTERISTICS

2-1. Viewing Angle by Contrast Ratio ≥ 10

Left : 60° typ., 50° min.
Right : 60° typ., 50° min.
Top : 55° typ., 40° min.

Bottom : 45° typ., 40° min.
2-2. Luminance : 160(min), 200(typ)
2-3. Contrast Ratio : 150(min), 250(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 Ω

3-3. Operating Frequency

Horizontal : 31 ~ 61kHz
Vertical : 56 ~ 75Hz

4. POWER SUPPLY

4-1. Power Adaptor

Input : AC 100~240V, 50/60Hz 1.2A
Output : DC 12V 3.0A

4-2. Power Consumption

5. ENVIRONMENT

5-1. Operating Temperature: 10°C~35°C (50°F~95°F)

(Ambient)

5-2. Relative Humidity : 5%~95%

(Non-condensing)

5-3. MTBF : 40,000(Min)

6. DIMENSIONS (with TILT/SWIVEL)

Width : 389.2mm (15.32'')
Depth : 161.8mm (6.37'')
Height : 382.4mm (15.05'')

7. WEIGHT (with TILT/SWIVEL)

Net. Weight : 4.8kg (10.58 lbs)
Gross Weight : 6.8kg (14.99 lbs)

8. Audio Spec

8-1. Audio AMP

Input : 0.700Vrms
Output : 1Wrms+1Wrms
S/N : more then 40dB

8-2. Speaker

Impedance : 4

Ω

input : Max: 1.5W, Normal: 1W

SPECIFICATIONS ................................................... 2

PRECAUTIONS ....................................................... 3

TIMING CHART ....................................................... 4

OPERATING INSTRUCTIONS ................................ 5

WIRING DIAGRAM ................................................. 6

BLOCK DIAGRAM ................................................... 7

DESCRIPTION OF BLOCK DIAGRAM.....................8

ADJUSTMENT ........................................................ 9

TROUBLESHOOTING GUIDE .............................. 10

PRINTED CIRCUIT BOARD................................... 15

EXPLODED VIEW...................................................18

REPLACEMENT PARTS LIST ...............................20

PIN CONFIGURATION............................................24

SCHEMATIC DIAGRAM......................................... 26

MODE

POWER ON (NORMAL)

STAND-BY

SUSPEND

OFF

POWER OFF

H/V SYNC

ON/ON
OFF/ON
ON/OFF

OFF/OFF

-

POWER CONSUMPTION

less than 36 W

less than 3 W
less than 3 W

less than 3 W
less than 3 W

LED COLOR

GREEN
YELLOW
YELLOW
YELLOW

OFF

VIDEO

ACTIVE

OFF
OFF
OFF

-

- 3 -

WARNING FOR THE SAFETY-RELATED COMPONENT.

• There are some special components used in LCD
monitor that are important for safety. These parts are

marked on the schematic diagram and the
replacement parts list. It is essential that these critical

parts should be replaced with the manufacturer’s
specified parts to prevent electric shock, fire or other
hazard.

• Do not modify original design without obtaining written
permission from LG or you will void the original parts
and labor guarantee.

TAKE CARE DURING HANDLING THE LCD MODULE
WITH BACKLIGHT UNIT.

• Must mount the module using mounting holes arranged
in four corners.

• Do not press on the panel, edge of the frame strongly
or electric shock as this will result in damage to the
screen.

• Do not scratch or press on the panel with any sharp
objects, such as pencil or pen as this may result in
damage to the panel.

• Protect the module from the ESD as it may damage the
electronic circuit (C-MOS).

• Make certain that treatment person’s body are
grounded through wrist band.

• Do not leave the module in high temperature and in
areas of high humidity for a long time.

• The module not be exposed to the direct sunlight.

• Avoid contact with water as it may a short circuit within
the module.

• If the surface of panel become dirty, please wipe it off
with a softmaterial. (Cleaning with a dirty or rough cloth
may damage the panel.)

WARNING

BE CAREFUL ELECTRIC SHOCK !

• If you want to replace with the new backlight (CCFL) or
inverter circuit, must disconnect the AC adapter
because high voltage appears at inverter circuit about
650Vrms.

• Handle with care wires or connectors of the inverter
circuit. If the wires are pressed cause short and may
burn or take fire.

PRECAUTION

CAUTION

Please use only a plastic screwdriver to protect yourself
from shock hazard during service operation.

TIMING CHART

- 4 -

VIDEO

SYNC

B

D

C

F

E

A

H / V

H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)
H (Pixels)
V (Lines)

Sync

Polarity

+

–
–

+

–
–
–
–
–
–
–
–

+
+
+
+
+
+
+
+

–
–
–
–
–
–

+
+

Dot

Clock

25.175

28.322

25.175

30.24

31.5

31.5

36.0

40.0

50.0

49.5

57.2832

65

75

78.75

Frequency

31.468 KHz

70.0 Hz

31.468 KHz

70.0 Hz

31.469 KHz

60.0 Hz

35.00 KHz

66.67 Hz

37.861 KHz

72.8 Hz

37.50 KHz

75.0 Hz

35.156 KHz

56.25 Hz

37.879 KHz

60.3 Hz

48.077 KHz

72.188 Hz

46.875 KHz

75.0 Hz

49.725 KHz

74.55 Hz

48.363 KHz

60.0 Hz

56.476 KHz

70.0 Hz

60.023 KHz

75.0 Hz

Resolution

640 x 350

720 x 400

(TEXT)

640 x 480

640 x 480

640 x 480

640 x 480

800 x 600

800 x 600

800 x 600

800 x 600

832 x 624

(MAC)

1024 x 768

1024 x 768

1024 x 768

Total

Period

( E )

800
449
900
449
800
525
864
525
832
520
840
500

1024

625

1056

628

1040

666

1056

625

1152

667

1344

806

1328

806

1312

800

Video

Active

Time ( A )

640
350
720
400
640
480
640
480
640
480
640
480
800
600
800
600
800
600
800
600
832
624

1024

768

1024

768

1204

768

Blanking

Time

( B )

160

99

180

49

160

45

224

45

192

40

200

20

224

25

256

28

240

66

256

25

320

43

320

38

304

38

288

32

Sync

Duration

( D )

96

2

108

2

96

2

64

3

40

3

64

3

72

2

128

4

120

6

80

3

64

3

136

6

136

6

96

3

Back

Porch

( F )

48
60
55
34
48
33
96
39

128

28

120

16

128

22
88
23
64
23

160

21

224

39

160

29

144

29

176

28

Front

Porch

( C )

16
37
17
13
16
10
64

3

24

9

16

1

24

1

40

1
56
37
16

1
32

1
24

3
24

3
16

1

MODE

1

2

3

4

5

6

7

8

9

10

11

12

13

14

AUTO

VOL

MUTE MENU

SET

OPERATING INSTRUCTIONS

- 5 -

FRONT VIEW REAR VIEW

Front Control Panel

24V

AUDIO
DCOUT

MIC.

IN

AUDIO

IN

MIC.
OUT

Power (DPMS) Indicator

1. Power ON/OFF Button

Use this button to turn the monitor On or Off.

2. Power Indicator

This indicator lights up green when the monitor
operates normally. If the monitor is in DPM (Energy
Saving) mode (stand-by/ suspend/power off), this
indicator color changes to yellow.

3. AUTO/SET Button

Use this button to enter a selection in the on
screen display.

* AUTO adjustment function

Touch the AUTO/SET button
before using OSD menu.
This button is for the automatic
adjustment of the screen position, clock and phase.

Note: Some signal from some graphics boards may not
function properly. If the results are unsatisfactory, adjust
your monitor’s Position, Clock and Phase manually.

4.

Use these buttons to choose or adjust
items in the on screen display.

Use to adjust the brightness.
Use to adjust the volume.

5. MENU Button

Use this button to enter and from the on

screen display (OSD).

6. MUTE Button

Use this button to turn on the audio or off.

Power ON/OFF Button

Front Control Panel

DC Power Connector

MIC. IN

MIC. OUT

HEAD PHONE

AUDIO IN

D-Sub

Signal Connector

-

+

PROCESSING

AUTO CONFIGURATION

Buttons

1356

24

VOL

AUTO

SET

MENU

MUTE

MUTE MENU

AUTO

VOL

SET

- 6 -

WIRING DIAGRAM

J4

CN2

CN1

J4

J10

J5

J3

Connector Ass’y P/N: 6631T11012N

BLOCK DIAGRAM

- 7 -

Power Part

DC/DC

Converter

(L4973)

12V

ST5V

ST5V

EEPROM

24WC08

ADC/PLL/Scaler

(gmZAN1)

(MICOM)

(MTV312)

Switch

FDC6325L

Schmitt Trigger

(74HCT14)

RGB

H.V

D-

Sub

15P

DDC

Control

DC

Jack

SCL

SDA

CON

10P

Inverter

3.3 VD

3.3V_PL

Module Power

3.3V

3.3V_PL

3.3VD

2.5VD

5VR

RGB

3.3V_AD

Regulator

BA033S

3.3V_AD

Headphone

MIC In

MIC Out

Audio In

Audio

Processor

(TDA7449)

Audio Amp

(TDA7496L)

SCLSDA

78 M08

8VA

12V

12V(Audio B/d)

Audio Mute

(Audio B/d)

CON 5P

12V

GND

SCL

SDA

Audio

Mute

12V

Audio Mute

LCD

Interface

20Pin

Connector

(12507WR-20P)

LVDS

(LVDS83)

RIN

RCLK

Regulator

BA033S

Hsync2

Vsync2

Hsyncm

Vsyncm

+3.3V

CON 5P

To Audio B/d

Main B/d

Audio B/d

7805

5VR

2.5VD

Regulator

1725

DESCRIPTION OF BLOCK DIAGRAM

- 8 -

1. Scaler One chip IC(GMZAN2, U201)

GMZAN2 (U201) is one chip IC which it supports four internal function blocks of Video Amp, PLL,
A/D converter and Video processor.
Video signal (0.7Vp.p) clamped through C209, 208, 207 with matching IC’s proper cut off voltage.
This signal is processed as a proper 8 bit digital signal by U201’s amplifying, phase locking, A/D converting,
and scaling operations.
U3 generates Clock, Horizontal and Vertical sync, Data Enable signals as LCD Panel’s input signals.

2. System Controller (Microprocessor) Circuit.

1) Microprocessor (U501) distinguishes polarity and frequency by calculating horizontal and vertical sync input
from signal source.

2) Microprocessor (U501) carries out power control by sending power-down trigger signal to each IC.

3) Microprocessor (U501) communicates with EEPROM (U502), and GMZAN2 (U201)
through IIC(2 lines) or 6 bit bus line. It makes all devices operated properly.

4) Microprocessor (U501) let User adjust screen by OSD function.

3. DC/ DC Converter.

This circuit supplies DC power for each device needing DC voltage of 3.3VD, 3.3V_AD, 3.3V_PL, Module Power 3.3V

and 5VS.
L4978(U801) , the DC/DC controller IC converts input 12Vdc into 5VS and 3.3Vdc, 2.5Vdc with peripheral circuit
composed of condensing components (ZD801, C810), and Regulators(U802,U805).
MODPWR(3.3V) for LCD module power is Regulator by U805, Regulator, controlled by Microprocessor.

3.3VD, 3.3V_AD, and 3.3V_PL for GMZAN2 (U201) and 3.3V for LVDS (U401) are switched by U804, switching FET,

controlled by Microprocessor for Power saving.

4. Display Data Transmitter Part (LVDS).

This part transmit digital signal from the Scaler to the receiver of module.

5. Audio Part (TDA7449,TDA7496L)

In This Circuit, Audio Processor(TDA7449) Which is Controlled by Microprocessor(U501) adjust
volume/treble/bass/balance of Audio signal which come from PC.
The Signal come from TDA7449 is amplified by TDA7496L. The final output signal is output through speaker.

ADJUSTMENT

- 9 -

220

IBM
Compatible PC

PARALLEL PORT

Power inlet (required)

Power LED

ST Switch

Power Select Switch
(110V/220V)

Control Line

Not used

RS232C

PARALLEL

V-SYNC

POWER

ST

VGS

MONITOR

E

E

V-Sync On/Off Switch
(Switch must be ON.)

F

F

A

A

B

B

C

C

15

10

5

5

69

1

1

1

14

13

25

6

5V

5V

5V

4.7K

4.7K

4.7K

74LS06

74LS06

OFF ON

OFF

ON

11

Video Signal
Generator

24V

AUDIO
DC OUT

MIC.

IN

AUDIO

IN

MIC.
OUT

Figure 1. Cable Connection

All adjustment are thoroughly checked and corrected
when the monitor leaves the factory, but sometimes
several minor adjustment may be required.
Adjustment should be following procedure and after
warming up for a minimum of 10 minutes.
Alignment appliances and tools.

- IBM Compatible PC

- Programmable Signal Generator.
(eg. VG-819 made by Astrodesign Co.)

- E(E)PROM with each mode data saved.

- Alignment Adapter and Software.

1. Adjustment for Factory Preset Mode

1) Run alignment program for LM568E on the IBM
compatible PC.

2) Display cross hatch pattern at Mode 1.

3) Select EEPROM ALL Init command and Enter.

4) Press "Y" key, it will automatically save all FOS data
to EEPROM.

2. Adjustment for White Balance

1) Display color 0,0 pattern at Mode 12.

2) Set External Bright to MAX position and Contrast to
MAX Position.

3) Select PRESET START

→ BIAS CAL command

and Enter.

4) No attempt to manually adjust, BIAS data is auto­matically adjusted and saved to the EEPROM.

5) Display color 15,0 pattern at Mode 12.

6) Select DRIVE CAL command and Enter.

7) Color 1 (9300K) and Color 2 (6500K) are
automatically adjusted and saved to the EEPROM.

8) Select PRESET EXIT command and Enter.

3. DDC Data Write Procedure

1) Use this procedure only when there is some
probelm on EDID data.

2) Select EEPROM → EDID Write command and
Enter.

3) This will write the EDID data to EEPROM.

- 10 -

TROUBLESHOOTING GUIDE

1. NO POWER

CHECK U501,

U803 LINE

CHECK

U803 PIN 1

VOLTAGE

(12V) ?

NO

NO POWER

(POWER INDICATOR OFF)

CHECK ADAPTER,

AND FIND OUT

A SHORT POINT

AS OPENING

EACH POWER LINE

CHECK J04’S

VOLTAGE

(12V) ?

NO

CHECK U803

CHECK

U803 PIN 3

Voltage

(5V) ?

NO

YES

YES

YES

CHECK KEY CONTROL

CONNECTOR ROUTINE

CHECK U501

CHECK

U501 PIN 8

Voltage

(5V) ?

NO

YES