LG 23LS7D-JA Schematic

website:http://biz.LGservice.com

LCD TV

SERVICE MANUAL

CHASSIS : LJ71A

MODEL : 23LS7D 23LS7D-JA

CAUTION

BEFORE SERVICING THE CHASSIS,

READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CONTENTS

CONTENTS ..............................................................................................	2
SAFETY PRECAUTIONS ........................................................................	3
SPECIFICATION ......................................................................................	4
ADJUSTMENT INSTRUCTION ...............................................................	7
TROUBLE SHOOTING ..........................................................................	11
WIRING DIAGRAM ................................................................................	17
BLOCK DIAGRAM .................................................................................	18
EXPLODED VIEW ..................................................................................	20
REPLACEMENT PARTS LIST ..............................................................	22
SVC. SHEET ...............................................................................................

- 2 -

SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the Schematic Diagram and Replacement Parts List.

It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent Shock, Fire, or other Hazards.

Do not modify the original design without permission of manufacturer.

General Guidance

An isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC power line. Use a transformer of adequate power rating as this protects the technician from accidents resulting in personal injury from electrical shocks.

It will also protect the receiver and it's components from being damaged by accidental shorts of the circuitry that may be inadvertently introduced during the service operation.

If any fuse (or Fusible Resistor) in this TV receiver is blown, replace it with the specified.

When replacing a high wattage resistor (Oxide Metal Film Resistor, over 1W), keep the resistor 10mm away from PCB.

Keep wires away from high voltage or high temperature parts.

Before returning the receiver to the customer,

always perform an AC leakage current check on the exposed metallic parts of the cabinet, such as antennas, terminals, etc., to be sure the set is safe to operate without damage of electrical shock.

Leakage Current Cold Check(Antenna Cold Check)

With the instrument AC plug removed from AC source, connect an electrical jumper across the two AC plug prongs. Place the AC switch in the on position, connect one lead of ohm-meter to the AC plug prongs tied together and touch other ohm-meter lead in turn to each exposed metallic parts such as antenna terminals, phone jacks, etc.

If the exposed metallic part has a return path to the chassis, the measured resistance should be between 1MΩ and 5.2MΩ.

When the exposed metal has no return path to the chassis the reading must be infinite.

An other abnormality exists that must be corrected before the receiver is returned to the customer.

Leakage Current Hot Check (See below Figure) Plug the AC cord directly into the AC outlet.

Do not use a line Isolation Transformer during this check.

Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth ground (Water Pipe, Conduit, etc.) and the exposed metallic parts.

Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more sensitivity.

Reverse plug the AC cord into the AC outlet and repeat AC voltage measurements for each exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which is corresponds to 0.5mA.

In case any measurement is out of the limits specified, there is possibility of shock hazard and the set must be checked and repaired before it is returned to the customer.

Leakage Current Hot Check circuit

AC Volt-meter

					Good Earth Ground
					such as WATER PIPE,
	To Instrument’s				CONDUIT etc.
		0.15uF
	exposed
	METALLIC PARTS

1.5 Kohm/10W

- 3 -

SPECIFICATION

NOTE : Specifications and others are subject to change without notice for improvement.

1. Application range	3. Test method
This specification sheet is applied to the 20”/ 23” Wide LCD	(1)	Performance : LGE TV test method followed
Digital TV used LJ71A chassis.	(2)	Demanded other specification

2. Requirement for Test	Safety : JQA Specification
	EMC : JQA Specification
Each part is tested as below without special appointment.

(1)Power : Standard input voltage (100V, 50/60Hz)

(2)Specification and performance of each parts are followed each drawing and specification by part number in accordance with BOM

(3)The TV set must be operated for about 20 minutes prior to the adjustment.

4.General Specification(TV)

No	Item			Specification	Remark
1	Video input applicable system	NTSC-M/ ISDB-S
2	RF Input Channel	1)	VHF	: 1 ~ 12
		2)	UHF	: 13 ~ 62
		3) CATV		: C13 ~ C38
		4)	Terr. digital	: 000 ~ 999	(Logical CH Number)
		5)	BS digital	: 000 ~ 999	(Logical CH Number)
		6)	CS digital	: 000 ~ 999	(Logical CH Number)
3	Input Voltage	100V~, 50/60Hz
4	Market	Japan
5	Tuning System	FS
6	Operating Environment	Temp : 0 ~ 40 deg
		Humidity : 10~90 %RH
7	Storage Environment	Temp : -20 ~ 50 deg
		Humidity : 10~90 %RH
8	Display	LCD Module

- 4 -

5.Module Specification

5.1.23”LCD Module (AUO T230XW01 V3)

No.

Item

Min

Typ.

Max

Unit

Remark

1

Display area

508.152 (H) x 285.696 (V)

mm

2

Outline dimension

546.0 (H) x 318.3 (V) x 46.0 (D)

mm

Typ

3

Number of Pixels

1366 (H) x 768(V)

1Pixel=3RGB Cells

4

Cell pitch

372 μm (H) x 372 μm (V)

μm

1Pixel=3RGB Cells

5

Color arrangement

RGB vertical stripe

6

Weight(net)

3.3

Kg

7

Operating Environment

Temperature

0 ~ 50

deg

Humidity

10 ~ 90

%

8

Storage Environment

Temperature

-20 ~ 60

deg

Humidity

10 ~ 90

%

9

Electrical Interface

LVDS

10

Back light Unit

6 CCFL (6 lamps)

11

R/T

8ms

Typ.

5.2. Optical characteristic specifications

No.

Item

Specification

Min

Typ.

Max

Remark

1

Viewing Angle

R/L

80/80

<CR≥10>

U/D

80/80

2

Luminance

Luminance (cd/m2)

400

500

3

Contrast Ratio

CR

550

700

All white / All black

4

CIE Color Coordinates

WHITE

Wx

Typ.

0.280

Typ.

In AV input

Wy

-0.03

0.292

+0.03

PSM : Dynamic

RED

Rx

0.638

White (100 IRE)

Ry

0.337

GREEN

Gx

0.299

Gy

0.604

BLUE

Bx

0.145

By

0.059

- 5 -

6. Model Specification

No.		Item		Specification	Remark
1	Analog-terrestrial		Broadcasting system	NTSC-M
			RF Input Channel	VHF : 1~12
				UHF : 13~62
				CATV : C13~C38
2	Digital-terrestrial		Broadcasting system	ISDB-T
			RF Input Channel	000~999 CH.	Logical CH Number
3	Digital-BS/SC		Broadcasting system	ISDB-S
			RF Input Channel	000~999 CH.
4	Video Input			NTSC-3.58	NTSC4.43/PAL/PAL60/SECAM -> No Guarantee
5	S-Video Input			NTSC-3.58	NTSC4.43/PAL/PAL60/SECAM -> No Guarantee
6	D-terminal Input			Y/ Pb/Pr(D4: 480i/480P/720P/1080i)	576i/576p/720p(50Hz)/1080i(50Hz) -> No Guarantee
7	HDMI Input			HDMI
8	Audio Input			L/R Input	3EA : CVBS, S-video, D-terminal
9	Digital Optical Audio	output		AAC 5.1c Output	Available for Digital TV only
				PCM 2ch Output
10	Modem			2400bps(max)
11	Conditional Acess System			B-CAS System
12	EPG
13	DATA Broadcasting

7. Component Video Input (Y, P , P )
				B	R
	No	Resolution	H-freq(kHz)		V-freq.(kHz)	Pixel clock(MHz)	Proposed
	1	720*480	15.73		59.94	13.500	SDTV, DVD 480I
	2	720*480	15.75		60.00	13.514	SDTV, DVD 480I
	3	720*480	31.47		59.94	27.000	SDTV 480P
	4	720*480	31.50		60.00	27.027	SDTV 480P
	5	1280*720	44.96		59.94	74.176	HDTV 720P
	6	1280*720	45.00		60.00	74.250	HDTV 720P
	7	1920*1080	33.72		59.94	74.176	HDTV 1080I
	8	1920*1080	33.75		60.00	74.250	HDTV 1080I

8. HDMI input (DTV)

No	Resolution	H-freq(kHz)	V-freq.(kHz)	Pixel clock(MHz)	Proposed
1	720*480	15.73	59.94	13.500	SDTV 480I
2	1440*480	15.75	60.00	27.027	SDTV 480I
3	720*576	15.63	50.00	13.500	SDTV 576I
4	1440*576	15.63	50.00	27.000	SDTV 576I
5	720*480	31.47	59.94	27.000	SDTV 480P
6	720*480	31.50	60.00	27.027	SDTV 576P
7	720*576	31.25	50.00	27.000	SDTV 576P
8	1280*720	37.5	50.00	74.250	HDTV 720P
9	1280*720	44.96	59.94	74.176	HDTV 720P
10	1280*720	45.00	60.00	74.250	HDTV 720P
11	1920*1080	33.72	59.94	74.176	HDTV 1080I
12	1920*1080	33.75	60.00	74.250	HDTV 1080I
13	1920*1080	28.125	50.00	74.250	HDTV 1080I

- 6 -

ADJUSTMENT INSTRUCTION

1. Application Range

This specification sheet is applied to 20”/ 23” LCD TV which is manufactured in TV (or Monitor) Factory or is produced on the basis of this data.

2.Specification

1)The adjustment is according to the order which is designated and which must be followed, according to the plan which can be changed only on agreeing.

2)Power Adjustment: 100V, 50/60Hz

3)Magnetic Field Condition: Nil.

4)Input signal Unit: Product Specification Standard

5)Reserve after operation: Above 30 Minutes

6)Adjustment equipments: Color Analyzer(CA-210 or CA110), Pattern Generator (MSPG-925L or Equivalent), DDC Adjustment Jig equipment, SVC remote control

3.Main PCB check process

* APC - After Manual-Insert, executing APC

3.1. Download

1)Execute ISP program “Mstar ISP Utility”

2)Click “Config” and set as below

3)Click “Auto Detect” and check “OK” message.

If “Error” is displayed, check connecting computer, jig, and set again.

4) Click “Connect”.

If “Can’t” is displayed, check connecting computer, jig, and set.

(5)

filexxx.bin

(7) .......

OK

(6)

3.2.ADC Process

(1)COMPONENT input ADC

1)Component Gain/Offset Adjustment

-Convert to Component in Input-source

-Signal equipment displays Impress Resolution 480P

MODEL : 212 in Pattern Generator

(480p Mode, Y : 100%, Pb/Pr : 100%) PATTERN : 08 in Pattern Generator

(MSPG-925 Series)

-Adjust by commanding AUTO_COLOR_ADJUST (0xF1) 0x00 0x02 instruction.

2)Confirmation

-We confirm whether “0x8E” address of EEPROM “0xB4” is “0xAA” or not.

-If “0x8E” address of EEPROM “0xB4” isn’t “0xAA”, we adjust once more.

-We can confirm the ADC values from “0x00~0x05” addresses in a page “0xB4”.

5) Click “Read” tab, and then load download file(XXXX.bin) by					3.3. Function Check
clicking “Read”.					(1) Check display and sound
					- Check Input and Signal items. (cf. work instructions)
					1)	TV
					2) AV1 : CVBS
					3)	AV2 : CVBS/ S-Video
					4)	COMPONENT : D-terminal(D4)
					5) HDMI

* Display and Sound check is executed by Remote control.

6)Click “Auto” tab and set as below.

7)click “Run”.

8)After downloading, check “OK” message.

- 7 -

4. Total Assembly line process

4.1. Adjustment Preparation

- Above 30 minutes H/run in RF no signal

4.2.Confirm color coordinate of component

(1)Set Input to COMPONENT.

(2)Input signal : 480P

Full white 216/255 gray level (85 IRE Model : 212, Pattern : 78 at MSPG925L)

(3)Set PSM : Dynamic / CSM : Cool

(4)Confirm whether x = 0.276+±0.03, y = 0.283±0.03 or not.

4.3.Confirm color coordinate of AV2

(1)Set Input to AV2

(2)Input signal : CVBS, NTSC-M

Full white 216/255 gray level (85 IRE, Model : 201, Pattern

:78 at MSPG925L)

(3)Set PSM : Dynamic / CSM : Cool

(4)Confirm whether x = 0.276±0.03, y = 0.283±0.03 or not.

4.4.Other quality

-Confirm that each items satisfy under standard condition that was written product spec.

-Confirm Video and Sound at each source

(1)Analog TV

-Select input Analog TV and check whether picture is displayed or not.

(2)Terrestrial Digital TV

-Select input Terrestrial Digital TV and check whether

picture is displayed or not.

* Use ISDB-T Signal Generator(LG3802) and Stream (Ch11, NHK1, Freq.473.143MHz) stored in the Generator.

Caution) It’s necessary to connect B-CAS CARD when you check this source.

4.5. Power Consumption

1)Press “EYE” button on LG Adjust remocon and check whether LED color is amber or not.

2)Press “POWER” button on LG Ajust remocon to enter Stand-by mode.

3)Check the power consumption. (Under 1W)

4.6. HDCP setting

(High-Bandwidth Digital Contents Protection)

-Connect HDMI cable to HDMI jack.

-Input HDCP key with HDCP-key-in-program.

-HDCP key value is stored on EEPROM(AT24C64) which is E00~F20 addresses of 0xBC~0xBE page.

-AC off/on and on HDCP button of MSPG925 and confirm whether picture is displayed or not of using MSPG925.

-HDCP key value is different among the sets.

4.7DDC EDID Write

1)Connect HDMI Signal Cable to HDMI Jack.

2)Write EDID DATA to EEPROM(24C02) by using DDC2B protocol.

3)Check whether written EDID data is correct or not. (refer to Product spec).

<DIGITAL DATA 256Byte>

(3) Satellite Digital TV (BS/CS)

Select input BS satellite Digital TV and check whether picture is displayed or not.

Caution) It’s necessary to connect B-CAS CARD when you check this source.

(4)AV1

-Select input AV1 (CVBS) and whether picture is displayed or not.

(5)AV2

-Select input AV2 (CVBS/S-video) and whether picture is displayed or not

(6)COMPONENT

-Select input COMPONENT and whether picture is displayed or not.

(7)HDMI

- Select input HDMI and whether picture is displayed or not

4.8. Modem Communication check

1)Connect a telephone wire between TV and Terminal adapter (MN128mini-SV1)

2)Press “EYE” button on LG Adjust Remocon and chek whether Power LED color is amber or not.

3)Press “MODE” button on LG Adjust Remocon and check whether the other LED color is red or not.

4)After “ test” is progressing automatically in DTV menu, check whether the message is displayed or not as below. (During “test”, color of the other LED is green.)

If the message is displayed, Modern communication test is OK.

- 8 -

4.9. Hi-POT

Confirm whether is normal or not when between power board’s as block and GND is impacked on 1500 Vac or 2121 Vdc/1sec for one second.

(Judgment condition

:1) Supply DC voltage -> set cut-off current to 10mA 2) Supply AC voltage -> set cut-off current to 100mA)

4.10. Insulation

After setting above condition, supply 500Vdc and then measure the insultion resistance(Spec : above 4M ohm)

4.11. Outgoing condition Configuration

- Analog/ Digital TV Initializing

1) Press “EYE” button on LG ADJUST REMOCON.

(If Pressed “EYE” button on LG ADJUST REMOCON, Color of Power LED will be Amber)

2)Press “IN-STOP” button on LG ADJUST REMOCON. It is

executed 3~15 procedure automatically by Software

program.(If pressed “IN-STOP” button, Color of “

” LED will be RED)

3)After Initializing is finished, the TV set turns off automatically.

4.10. Option data setting(SVC OSD setting)

TOOL OPTION	17280
AREA OPTION	0
OPTION 1	6
OPTION 2	2
OPTION 3	2
OPTION 4	0
OPTION 5	9

*Tool/Area option confirm.

If Tool option(17280)/Area option(0) is not, change the Tool option(17280)/Area(0) value compulsorily.

5. Adjustment Command

5.1. Adjustment Commands(LENGTH=84)

Adjustment Contents	CMD(hex)	ADR	VAL	Description
FACTORY ON	E0	00	00	Factory mode on
FACTORY OFF	E2	00	00	Factory mode off
EEPROM ALL INIT.	E4	00	00	EEPROM All clear
EEPROM Read	E7	00	00	EEPROM Read
EEPROM Write	E8	00	data	EEPROM Write by some values
COLOR SAVE (R/G/B cutoff, Drive, Contrast, Bright)	EB	00	00	Color Save
H POSITION	20	00	00 – 100	They have different range each mode, FOS Adjustment.
V POSITION	30	00	00 – 100
CLOCK	90	00	00 – 100
PHASE	92	00	00 – 100
R DRIVE	16	00	00 – FF	Drive adjustment
G DRIVE	18	00	00 – FF
B DRIVE	1A	00	00 – FF
R CUTOFF	80	00	00 – 7F	Offset adjustment
G CUTOFF	82	00	00 – 7F
B CUTOFF	84	00	00 – 7F
BRIGHT	10	00	00 – 3F	Bright adjustment
CONTRAST	12	00	00 - 64	Luminance adjustment
AUTO_COLOR_ADJUST	F1	00	02	Auto COLOR Adjustment
CHANGE_COLOR_TEMP	F2	00	0,1,2,3	0 : COOL, 1 : NORMAL, 2 : WARM, 3 : USER
FACTORY_DEFAULT	F3	00	00	Factory mode off & II_SW is “1” & Input change to “ TV”
AUTO_INPUT CHANGE	F4	00	0,1,2,4	0:ATV, 1:Video1, 2:Video2, 3:DTV, 4:D-TERMNAL, 5:HDMI

- 9 -

5.2EEPROM DATA READ

(1)Signal Table

Delay 100ms

128 Bytes

(2) Command Set

Adjustment contents	CMD(hex)	ADH(hex)	ADL(hex)	Details
EEPROM READ	E7	A0	0	0-Page 0~7F Read
			80	0-Page 80~FF Read
		A2	0	1-Page	0~7F Read
			80	1-Page 80~FF Read
		A4	0	2-Page	0~7F Read
			80	2-Page 80~FF Read
		A6	0	3-Page	0~7F Read
			80	3-Page 80~FF Read

* Purpose : To read the appointment Address of E2PROM by 128(80h)-byte

5.3.E2PROM Data Write

(1)Signal Table

LEN : 84h+Bytes CMD : 8Eh

ADH : E2PROM Slave Address(A0,A2,A4,A6,A8), Not 00h(Reserved by BufferToEEPROM)

ADL : E2PROM Sub Address(00~FF) Data : Write data

(2) Command Set

Adjustment contents	CMD(hex)	ADH(hex)	Details
EEPROM WRITE	E8	94	16-Byte Write
		84+n	n-byte Write

*Purpose

1)EDID write : 16-byte by 16-byte, 8 order (128-byte) write(TO “00 – 7F” of “EEPROM Page A4”).

2)FOS Default write : 16-mode data (HFh, HFl, VF, STD, HP, VP, Clk, ClkPh, PhFine) write.

3)Random Data write : write the appointment Address of E2PROM.

5.4. VRAM Read

1)Send CMD(70h) to read Video RAM value from MICOM And save its value to 128-Bytes Buffer.(Common Buffer for the use of EDID)

2)Delay 500ms. (Time to Wait and Read Video RAM from MICOM)

3)Be transmitted the contents of MICOM’s 128-bytes Buffer to PC. (128th Data is the CheckSum of 127-bytes data : That’s OK if the value of adding 128-bytes Data is Zero)

Data 128

- 10 -

TROUBLE SHOOTING

1. No Power (LED indicator off) : [A] Process

Check 12V or ST_5V of Power B/D.

Pass

Check Output of

IC1000, IC1004.

Pass

Check Output of

IC1006, IC1005.

Pass

Check Output of

IC1002, IC1003.

Pass

Check LED Assy.

Fail

Fail

Fail

Fail

Fail

Check short of Main B/D or Change Power B/D.

Check short of	Fail
IC100, Q308.

Pass

Change IC1000, IC1004.

Check short of	Fail
Q308, TU600, IC500.

Pass

Change IC1006, IC1005.

Check short of		Fail
IC100, IC400.

Pass

Change IC1002, IC1003.

Change LED Assy.

Pass

Check P306 Connector.

Re-soldering or Change defect part of IC100, Q308.

Re-soldering or Change defect part of Q308, TU600, IC500.

Re-soldering or Change defect part of IC100, IC400.

- 11 -

2. No RASTER : [B] Process

	Check LED status		Fail
					Repeat A PROCESS.
	On Display Unit.
		Pass

Check Panel Link				Fail
Cable or Module.
	Pass
				Fail
Check Inverter
Connector or
inverter.
	Pass
Check Output of				Fail
Q308.
	Pass
Check the LVDS				Fail
Output of IC100
	Pass

Check Input source Cable and Jack.

Change Panel Link Cable or Module.

Change Inverter Connector or Inverter.

Change Q308.

Change IC100

Fail

Change Module.

- 12 -

3. No RASTER on DTV Signal

Repeat [A,B] process
	Pass
			Fail
Check the input/
						Check the P901.
output of R918.
	Pass
Check the input/			Fail
						Re-soldering or Change the defect part.
output of R127.
	Pass
Check the input/			Fail
						Re-soldering or change the defect part.
output of IC100
						Check the X100
	Pass

Check and Change the Digital board.

- 13 -

4. No Raster on Component Signal

Repeat [A, B]

process.

		Pass
			Fail
	Check the input/
						Check the J801.
	output of R806.
		Pass
	Check		Fail
						Re-soldering or Change the defect part.
	the input/output
	of R121.

Pass

Check the	Fail		Re-soldering or change the
input/output of IC100.
			defect part, Check the X100.

Pass

Check input source cable and jack.

- 14 -