LG 49LJ510M, 49LJ5100 Schematic

CONFIDENTIAL

LED TV

SERVICE MANUAL

CHASSIS : LA77H

MODEL : 49LJ5100/510M

49LJ5100-UC/49LJ510M-UB

CAUTION

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

P/NO : MFL70080101 (1705-REV01)

Any reproduction, duplication, distribution (including by way of email, facsimile or other electronic means), publication, modification, copying or transmission of this Service Manual is STRICTLY PROHIBITED unless you have obtained the prior written consent of the LG Electronics entity from which you received this Service Manual. The material covered by this prohibition includes, without limitation, any text, graphics or logos in this Service Manual.

CONTENTS

CONTENTS ..............................................................................................	2
SAFETY PRECAUTIONS .........................................................................	3
SERVICING PRECAUTIONS ...................................................................	4
SPECIFICATION ........................................................................................	6
SOFTWARE UPDATE ..............................................................................	8
BLOCK DIAGRAM ...................................................................................	9
EXPLODED VIEW ..................................................................................	10
DISASSEMBLY GUIDE ..........................................................................	11
TROUBLE SHOOTING GUIDE ................................................	APPENDIX

- 2 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

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 Exploded View.

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 1 W), keep the resistor 10 mm 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 1 MΩ and 5.2 MΩ.

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 1.5 K / 10 watt resistor in parallel with a 0.15 uF 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 0.5 mA.

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

- 3 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

SERVICING PRECAUTIONS

CAUTION: Before servicing receivers covered by this service manual and its supplements and addenda, read and follow the SAFETY PRECAUTIONS on page 3 of this publication.

NOTE: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions on page 3 of this publication, always follow the safety precautions. Remember: Safety First.

General Servicing Precautions

1.Always unplug the receiver AC power cord from the AC power source before;

a.Removing or reinstalling any component, circuit board module or any other receiver assembly.

b.Disconnecting or reconnecting any receiver electrical plug or other electrical connection.

c.Connecting a test substitute in parallel with an electrolytic capacitor in the receiver.

CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.

2.Test high voltage only by measuring it with an appropriate high voltage meter or other voltage measuring device (DVM, FETVOM, etc) equipped with a suitable high voltage probe. Do not test high voltage by "drawing an arc".

3.Do not spray chemicals on or near this receiver or any of its assemblies.

4.Unless specified otherwise in this service manual, clean electrical contacts only by applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or comparable non-abrasive applicator; 10 % (by volume) Acetone and 90 % (by volume) isopropyl alcohol (90 % - 99 % strength)

CAUTION: This is a flammable mixture.

Unless specified otherwise in this service manual, lubrication of contacts in not required.

5.Do not defeat any plug/socket B+ voltage interlocks with which receivers covered by this service manual might be equipped.

6.Do not apply AC power to this instrument and/or any of its electrical assemblies unless all solid-state device heat sinks are correctly installed.

7.Always connect the test receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead.

Always remove the test receiver ground lead last.

8.Use with this receiver only the test fixtures specified in this service manual.

CAUTION: Do not connect the test fixture ground strap to any heat sink in this receiver.

Electrostatically Sensitive (ES) Devices

Some semiconductor (solid-state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by static by static electricity.

1.Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed to prevent potential shock reasons prior to applying power to the unit under test.

2.After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3.Use only a grounded-tip soldering iron to solder or unsolder ES devices.

4.Use only an anti-static type solder removal device. Some solder removal devices not classified as “anti-static” can generate electrical charges sufficient to damage ES devices.

5.Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.

6.Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material).

7.Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed.

CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8.Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES device.)

General Soldering Guidelines

1.Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that will maintain tip temperature within the range or 500 °F to 600 °F.

2.Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40 parts lead.

3.Keep the soldering iron tip clean and well tinned.

4.Thoroughly clean the surfaces to be soldered. Use a mall wirebristle (0.5 inch, or 1.25 cm) brush with a metal handle.

Do not use freon-propelled spray-on cleaners.

5.Use the following unsoldering technique

a.Allow the soldering iron tip to reach normal temperature. (500 °F to 600 °F)

b.Heat the component lead until the solder melts.

c.Quickly draw the melted solder with an anti-static, suctiontype solder removal device or with solder braid. CAUTION: Work quickly to avoid overheating the circuit board printed foil.

6.Use the following soldering technique.

a.Allow the soldering iron tip to reach a normal temperature (500 °F to 600 °F)

b.First, hold the soldering iron tip and solder the strand against the component lead until the solder melts.

c.Quickly move the soldering iron tip to the junction of the component lead and the printed circuit foil, and hold it there only until the solder flows onto and around both the component lead and the foil.

CAUTION: Work quickly to avoid overheating the circuit board printed foil.

d.Closely inspect the solder area and remove any excess or splashed solder with a small wire-bristle brush.

- 4 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

IC Remove/Replacement

Some chassis circuit boards have slotted holes (oblong) through which the IC leads are inserted and then bent flat against the circuit foil. When holes are the slotted type, the following technique should be used to remove and replace the IC. When working with boards using the familiar round hole, use the standard technique as outlined in paragraphs 5 and 6 above.

Removal

1.Desolder and straighten each IC lead in one operation by gently prying up on the lead with the soldering iron tip as the solder melts.

2.Draw away the melted solder with an anti-static suction-type solder removal device (or with solder braid) before removing

the IC.

Replacement

1.Carefully insert the replacement IC in the circuit board.

2.Carefully bend each IC lead against the circuit foil pad and solder it.

3.Clean the soldered areas with a small wire-bristle brush. (It is not necessary to reapply acrylic coating to the areas).

"Small-Signal" Discrete Transistor

Removal/Replacement

1.Remove the defective transistor by clipping its leads as close as possible to the component body.

2.Bend into a "U" shape the end of each of three leads remaining on the circuit board.

3.Bend into a "U" shape the replacement transistor leads.

4.Connect the replacement transistor leads to the corresponding leads extending from the circuit board and crimp the "U" with long nose pliers to insure metal to metal contact then solder each connection.

Power Output, Transistor Device

Removal/Replacement

1.Heat and remove all solder from around the transistor leads.

2.Remove the heat sink mounting screw (if so equipped).

3.Carefully remove the transistor from the heat sink of the circuit board.

4.Insert new transistor in the circuit board.

5.Solder each transistor lead, and clip off excess lead.

6.Replace heat sink.

Diode Removal/Replacement

1.Remove defective diode by clipping its leads as close as possible to diode body.

2.Bend the two remaining leads perpendicular y to the circuit board.

3.Observing diode polarity, wrap each lead of the new diode around the corresponding lead on the circuit board.

4.Securely crimp each connection and solder it.

5.Inspect (on the circuit board copper side) the solder joints of the two "original" leads. If they are not shiny, reheat them and if necessary, apply additional solder.

Fuse and Conventional Resistor

Removal/Replacement

1.Clip each fuse or resistor lead at top of the circuit board hollow stake.

2.Securely crimp the leads of replacement component around notch at stake top.

3.Solder the connections.

CAUTION: Maintain original spacing between the replaced component and adjacent components and the circuit board to prevent excessive component temperatures.

Circuit Board Foil Repair

Excessive heat applied to the copper foil of any printed circuit board will weaken the adhesive that bonds the foil to the circuit board causing the foil to separate from or "lift-off" the board. The following guidelines and procedures should be followed whenever this condition is encountered.

At IC Connections

To repair a defective copper pattern at IC connections use the following procedure to install a jumper wire on the copper pattern side of the circuit board. (Use this technique only on IC connections).

1.Carefully remove the damaged copper pattern with a sharp knife. (Remove only as much copper as absolutely necessary).

2.carefully scratch away the solder resist and acrylic coating (if used) from the end of the remaining copper pattern.

3.Bend a small "U" in one end of a small gauge jumper wire and carefully crimp it around the IC pin. Solder the IC connection.

4.Route the jumper wire along the path of the out-away copper pattern and let it overlap the previously scraped end of the good copper pattern. Solder the overlapped area and clip off any excess jumper wire.

At Other Connections

Use the following technique to repair the defective copper pattern at connections other than IC Pins. This technique involves the installation of a jumper wire on the component side of the circuit board.

1.Remove the defective copper pattern with a sharp knife. Remove at least 1/4 inch of copper, to ensure that a hazardous condition will not exist if the jumper wire opens.

2.Trace along the copper pattern from both sides of the pattern break and locate the nearest component that is directly connected to the affected copper pattern.

3.Connect insulated 20-gauge jumper wire from the lead of the nearest component on one side of the pattern break to the lead of the nearest component on the other side.

Carefully crimp and solder the connections.

CAUTION: Be sure the insulated jumper wire is dressed so the it does not touch components or sharp edges.

- 5 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

SPECIFICATION

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

1. Application range			3. Test method
This specification is applied to the LED TV used LA77A			(1) Performance: LGE TV test method followed
chassis.			(2) Demanded other specification
			- Safety : CE, IEC specification
2. Test condition			- EMC : CE, IEC
2. Test condition
Each part is tested as below without special appointment.
(1) Temperature: 25 °C ± 5 °C, CST: 40 °C ± 2 °C
(2) Relative Humidity: 65 % ± 10 %
(3) Power Voltage
	: Standard input voltage (AC 100-240 V~, 50/60 Hz)
	* Standard Voltage of each products is marked by models.
(4) Specification and performance of each parts are followed
	each drawing and specification by part number in
	accordance with BOM.
(5) The receiver must be operated for about 5 minutes prior to
	the adjustment.
4. General Specification

No	Item	Specification		Remark

1	Market	North America

2	Receiving system	ATSC / NTSC-M, 64 & 256 QAM

3	Available Channel	VHF : 02~13

		UHF : 14~69

		DTV : 02-69
		CATV : 01~135
		CADTV : 01~135
4	Input Voltage	AC 110V, 60HZ		Mark : 110V, 60Hz (N.America)

5	Aspect Ratio	16:9

6	Tuning System	FS		Rear gender(1EA)

7	Operating Environment	1) Temp : 0 ~ 40 deg
		2) Humidity : ~ 80 %
8	Storage Environment	1) Temp. : -20 ~ 60 deg
		2) Humidity : ~ 85%

- 6 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

5. External Input Support Format

5.1. Component 2D input(Y, CB/PB)

No.	Resolution	H-freq(kHz)	V-freq.(kHz)	Pixel clock(MHz)	Proposed
1	720*480	15.73	59.94	13.50	SDTV ,DVD 480I
2	720*480	15.73	60.00	13.5135	SDTV ,DVD 480I
3	720*480	31.47	59.94	27.00	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	74.25	HDTV 720P

7	1920*1080	33.72	59.94	74.176	HDTV 1080I

8	1920*1080	33.75	60.00	74.25	HDTV 1080I

9	1920*1080	26.97	23.976	74.176	HDTV 1080P

10	1920*1080	27.00	24.00	74.25	HDTV 1080P
11	1920*1080	33.71	29.97	74.176	HDTV 1080P
12	1920*1080	33.75	30.00	74.25	HDTV 1080P
13	1920*1080	67.432	59.94	148.352	HDTV 1080P
14	1920*1080	67.50	60.00	148.50	HDTV 1080P

5.2. HDMI Input (PC/DTV)

No.	Resolution			H-freq(kHz)	V-freq.(kHz)		Pixel clock(MHz)			Proposed		Remark

	HDMI-PC										DDC
1	640*350	@70Hz		31.46	70.09		25.17		EGA		X
2	720*400	@70Hz		31.46	70.08		28.32		DOS		O
3	640*480	@60Hz		31.46	59.94		25.17		VESA(VGA)		O
4	800*600	@60Hz		37.87	60.31		40.00		VESA(SVGA)		O
5	1024*768	@60Hz		48.36	60.00		65.00		VESA(XGA)		O
6	1152*864	@60Hz		54.34	60.05		80.002		VESA		O
7	1280*1024	@60Hz		63.98	60.02		108.0		VESA (SXGA)		O		FHD only

8	1360*768	@60Hz		47.71	60.01		85.50		VESA (WXGA)		O

9	1920*1080	@60Hz		67.5	60.00		148.5		WUXGA(CEA 861D)		O		FHD only


No.	Resolution			H-freq(kHz)		V-freq.(kHz)		Pixel clock(MHz)			Proposed

	DTV

1	640*480		31.46			59.94		25.125			SDTV 480P

2	640*480		31.5			60.00		25.125			SDTV 480P

5	720*480		15.73			59.94		13.500			SDTV 480I

6	720*480		15.75			60.00		13.514			SDTV 480I
7	720*480		31.47			59.94		27.00			SDTV 480P
8	720*480		31.5			60.00		27.027			SDTV 480P
9	1280*720		44.96			59.94		74.176			HDTV 720P
10	1280*720		45			60.00		74.25			HDTV 720P
11	1920*1080		33.72			59.94		74.176			HDTV 1080I
12	1920*1080		33.75			60.00		74.25			HDTV 1080I
13	1920*1080		26.97			23.97		74.176			HDTV 1080P

14	1920*1080		27.00			24.00		74.25			HDTV 1080P

15	1920*1080		33.71			29.97		74.176			HDTV 1080P

16	1920*1080		33.75			30.00		74.25			HDTV 1080P

- 7 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

SOFTWARE UPDATE

1.USB

(1)Insert the USB memory Stick to the USB port

(2)Automatically detect the SW Version and show the below message

(3) Click [YES]: initiate the download and install of the update.

(4)Click [Check Now]: move to “About This TV” page for update

(5)TV is updating

(6) After finished the update, below Pop-up appear

(7)Click [Yes] : TV will be DC OFF -> ON

(8)After TV turned on, Check the updated SW Version and Tool Option

2. NSU

(This Function is needed to connect to the internet)

(1) Menu -> All Settings -> General -> About This TV

(2)Click [CHEK FOR UPDATES] : system check newest version

(3)Click [DOWNLOAD AND INSTALL]

(4)TV is updating

(5) After finished the update, below Pop-up appear

(6)Turn OFF the TV and On. Check the updated SW Version and Tool Option

- 8 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

.reserved rights All .Inc Electronics LG © Copyright - 9 - .purposes service and training for Only

19V_P JK201

( (

LED Driver		Module	IR/KEY

	P601


IC601
MP3378E
MP3378E

+12V	Q202	Panel_Vcc
	Q202
	SSM3J332R
IC205		USB_5V
IC205
MP2315GJ
IC202		VDDC_1.15V
IC202
TJ4320
		IC101
		Serial Flash
		64MB
		IC100
		EEPROM
		24C512

IC203

MP2315GJ AVDD_ST_3.3V

Q204	N_3.3V	IC204
Q204		IC204
SSM3J332R		TJ1117

S-AMP_19V

		Sound AMP
	LPF	NTP7515x
	LPF	IC5600
	LPF	IC5600
	LPF

P5600

		PWM	onINV							P300/301	IR KEY1,2	P303
		PWM	onINV						Panel_12V	SensorI2C	IR KEY1,2	LED
USB_DN													ST_3.3V
USB_DN
USB_DP
51	50	88	84	93	92	91	90	86	85	65,66,69 ~ 72,74~79
51	50	88	84					86	85

		SPI_DI	EEP SDA
27 46 47	122	SPI_CLK	EEP SCL
27 46 47	122	SPI_DO	EEP SCL
		SPI_DO

SPI_CZ

103

IC102

IR110

KEY2 1041105

LED106

DDR_1.8V

45 108

56 80 81

I2S_WS

I2S_SCK

I2S_SDO

Audio_SDA

Audio_SCL

LGE6312

(With DDR3 Max CLK 667MHz)

123~128,1,2,113,114 3~11,118,119 19,21,23,29,30 24,29,30

			In
HDMI2	HDM	Y,Pb,Pr In	Comp. R/L	AV1 In
HDMI2	HDM

JK404

JK400

JK401

57~64	DP USB	DN USB	5V USB

			JK403
43
	24Mhz
42
48		2 Tuner SDA
49		3	Tuner SCL
39	IF_N	10	IC501
39	IF_P		SI2151-A10
			SI2151-A10
38		11	IF_AGC
37		4	IF_AGC

95 94 9 15 17

B+

N_3.3V

JK501

Tx, Rx

JK402/P401/P402

Debug

DIAGRAM BLOCK

EXPLODED VIEW

IMPORTANT SAFETY NOTICE

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the EXPLODED VIEW.

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.

	901
400
540	902
LV1
800
	720
120	700
200	A10
500	AR1

- 10 -	Copyright ©	LG Electronics Inc. All rights reserved.
	Only for training and service purposes.

1.Disassembly of Back cover

(1)Remove screw in the set

(2) Check both right/left hole

(3) Attach tape to ‘Long nose pliers’

(4) Put ‘long nose’ into the hole

DISASSEMBLY

(5) Open B/C with push/pulling long nose to upper and lower sides.

(6) Disassemble Back cover

*Disassemble it from left to right for top side hook on Back cover

Tool spec

-Long nose pliers

-Needle nose pliers

:M3*5.5 1EA

: M4*10 4EA(Taptite)

: M3*10 5EA(Taptite)	w	W < 4.0mm
: M3*10 5EA(Taptite)

*SCREW TORQUE :


SCREW : 4 ~ 6Kgf.cm
SCREW : 5 ~ 7Kgf.cm		t< 3.0mm
SCREW : 5 ~ 7Kgf.cm
	t


SCREW : 5 ~ 7Kgf.cm

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	Only for training and service purposes.

TROUBLE SHOOTING GUIDE

Contents of Standard Repair Process

* First of all, Check whether there is SVC Bulletin in GSCS System for these model.

No.	Error symptom (High category)	Error symptom (Mid category)	Page	Remarks

1		No video/Normal audio	1

2		No video/No audio	2

3	A. Video error	Tuning fail, Picture broken/ Freezing	3, 4
	A. Video error
4		Color error	5

5		Vertical/Horizontal bar, residual image, light spot,	6
5		external device color error	6
		external device color error

6	B. Power error	No power	7

7		Off when on, off while viewing, power auto on/off	8
7		Off when on, off while viewing, power auto on/off	8

8	C. Audio error	No audio/Normal video	9

9		Wrecked audio/discontinuation/noise	10
9		Wrecked audio/discontinuation/noise	10

10	D. Function error	Remote control & Local switch checking	11

11		External device recognition error	12
11		External device recognition error	12

12	E. Noise	Circuit noise, mechanical noise	13

13	F. Exterior error	Exterior defect	14

Standard Repair Process

Error Symptom	A. Video Error	Established date	1/14

Content	No video / Normal audio	Revised date
Content	No video / Normal audio	Revised date

First of all, Check whether all of cables between board is inserted properly or not.

(Main B/D ↔ Adaptor, LVDS Cable, Speaker Cable, IR B/D Cable…)

Normal Y

No video

Check Back Light

Check LVDS 12 V

Replace T-con B/D

Normal audio

Audio

On with naked eye

of Main B/D

Voltage

or Module

Move to

Check Main B/D to LED Back light Voltage

Replace Main

No video/No audio

Normal

B/D or Repair parts

Change Module

Voltage

Replace Main

B/D or Repair parts

Precaution	A3 & A6
Always check & record S/W Version and White
Always check & record S/W Version and White		Replace Main Board	Re-enter White Balance value
Balance value before replacing the Main Board		Replace Main Board	Re-enter White Balance value
Balance value before replacing the Main Board

Standard Repair Process

Error Symptom	A. Video Error	Established date	2/14

Content	No video / No audio	Revised date
Content	No video / No audio	Revised date

	A13
No video /	Check voltage 19V	Normal Y	Replace Main
No audio	of Adaptor	Voltage	B/D or Repair parts

Replace Adaptor

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