LG 75UJ657, 75UJ64*0 Schematic

CONFIDENTIAL

LED TV

SERVICE MANUAL

CHASSIS : UA71Q

MODEL : 75UJ657* 75UJ657*-U*

MODEL : 75UJ64*0 75UJ64*0-U*

CAUTION

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

P/NO : MFL69823933 (1711-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 .............................................................................. 9

BLOCK DIAGRAM ................................................................................. 10

EXPLODED VIEW .................................................................................. 20

DISASSEMBLY GUIDE .......................................................................... 21

TROUBLE SHOOTING GUIDE ................................................ APPENDIX

- 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 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 -

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 conict 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 mod-

ule 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 specied 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 ammable mixture. Unless specied 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 xtures specied in this

service manual.

CAUTION: Do not connect the test xture 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 eld-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 classied as “anti-static” can generate electrical charges sufcient to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate

electrical charges sufcient 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 oor can generate static electricity sufcient 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, suction-

type 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 ows 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 -

IC Remove/Replacement

Some chassis circuit boards have slotted holes (oblong) through which the IC leads are inserted and then bent at 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.

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.

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.

- 5 -

SPECIFICATION

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

.

1. Application range

This specification is applied to the LED TV used UA71Q chassis.

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.

3. Test method

(1) Performance: LGE TV test method followed (2) Demanded other specification

- Safety : CE, IEC specification

- EMC : CE, IEC

4. General Specification

No Item Specication Remark

1 Market North America

2 Broadcasting 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 Receiving system Digital : ATSC, 64 & 256 QAM

Analog : NTSC-M

5 Video Input NTSC-M Rear gender(1EA)

6 Component Input Y/Cb/Cr, Y/ Pb/Pr Rear gender(1EA),

Rear (1EA) for UJ65

7 HDMI Input HDMI 1 PC / DTV format Side, Support 6Gbps

HDMI 2 PC / DTV format Side, Support 6Gbps, Support ARC

HDMI 3 PC / DTV format Rear, Support 6Gbps

HDMI 4 PC / DTV format Rear, Support 6Gbps Except for UJ63

8 Audio Input Component / AV Audio / DVI Audio L/R Input ; Rear(Gender)

Component and av and DVI use same jack ; L/R Input ; Rear for UJ65

9 SPDIF out(1EA) Optical Audio out Rear (1EA),

10 USB Input(3EA) EMF, DivX HD, For SVC (download) JPEG, MP3, DivX HD

Side(1EA), Rear(2EA) Side(1EA), Rear(1EA) for UJ65, UJ63

- 6 -

5. External Input Support Format

5.1. Component (Y, CB/PB, CR/PR)

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

1 720*480i 15.73 59.94 13.50 SDTV, DVD 480I(525I)

2 720*480i 15.75 60.00 13.51 SDTV, DVD 480I(525I)

3 720*480p 31.47 59.94 27.00 SDTV 480P

4 720*480p 31.50 60.00 27.02 SDTV 480P

5 1280*720p 44.96 59.94 74.17 HDTV 720P

6 1280*720p 45.00 60.00 74.25 HDTV 720P

7 1920*1080i 33.72 59.94 74.17 HDTV 1080I

8 1920*1080i 33.75 60.00 74.25 HDTV 1080I

9 1920*1080p 67.43 59.94 148.5 HDTV 1080P

10 1920*1080p 67.50 60.00 148.5 HDTV 1080P

5.2. HDMI Input (PC/DTV)

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

HDMI-PC

1 640*350 31.46 70.09 25.17 EGA

2 720*400 31.46 70.08 28.32 DOS

3 640*480 31.46 59.94 25.17 VESA(VGA)

4 800*600 37.87 60.31 40 VESA(SVGA)

5 1024*768 48.36 60.00 65 VESA(XGA)

6 1360*768 47.71 60.01 84.75 VESA(WXGA)

7 1152*864 54.34 60.05 80 VESA

8 1280*1024 63.98 60.02 109.00 SXGA Support to HDMI-PC

9 1920*1080 67.5 60 158.40 WUXGA

(Reduced Blanking)

10 1920*1080 135 120 297 UDTV 1080P

11 3840*2160 54 24.00 297.00 UDTV 2160P

12 3840*2160 56.25 25.00 297.00 UDTV 2160P

13 3840*2160 67.5 30.00 297.00 UDTV 2160P

14 4096*2160 53.95 23.97 296.70 UDTV 2160P

15 4096*2160 54 24 297 UDTV 2160P

- 7 -

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

DTV

1 640*480 31.46 59.94 25.12 SDTV 480P

2 640*480 31.5 60.00 25.12 SDTV 480P

3 720*480 15.73 59.94 13.50 SDTV, DVD

480I(525I)

4 720*480 15.75 60.00 13.51 SDTV, DVD

480I(525I)

5 720*576 15.62 50.00 13.50 SDTV, DVD

576I(625I) 50Hz

6 720*480 31.47 59.94 27 SDTV 480P

7 720*480 31.5 60.00 27.02 SDTV 480P

8 720*576 31.25 50.00 27 SDTV 576P

9 1280*720 44.96 59.94 74.17 HDTV 720P

10 1280*720 45 60.00 74.25 HDTV 720P

11 1280*720 37.5 50.00 74.25 HDTV 720P

12 1920*1080i 28.12 50.00 74.25 HDTV 1080I

13 1920*1080i 33.72 59.94 74.17 HDTV 1080I

14 1920*1080i 33.75 60.00 74.25 HDTV 1080I

15 1920*1080p 26.97 23.97 63.29 HDTV 1080P

16 1920*1080p 27.00 24.00 63.36 HDTV 1080P

17 1920*1080p 33.71 29.97 79.120 HDTV 1080P

18 1920*1080p 33.75 30.00 79.20 HDTV 1080P

19 1920*1080p 56.25 50.00 148.5 HDTV 1080P

20 1920*1080p 67.43 59.94 148.35 HDTV 1080P

21 1920*1080p 67.5 60.00 148.50 HDTV 1080P

22 1920*1080p 112.5 100 297.00 UDTV 1080P

23 1920*1080p 134.86 119.88 296.70 UDTV 1080P

24 1920*1080p 135.00 120 297 UDTV 1080P

25 3840*2160p 53.95 23.98 296.70 UDTV 2160P

26 3840*2160p 54 24.00 297.00 UDTV 2160P

27 3840*2160p 56.25 25.00 297.00 UDTV 2160P

28 3840*2160p 61.43 29.97 296.70 UDTV 2160P

29 3840*2160p 67.5 30.00 297.00 UDTV 2160P

30 3840*2160p 112.5 50.00 594 UDTV 2160P

31 3840*2160p 134.86 59.94 593.40 UDTV 2160P

32 3840*2160p 135 60.00 594 UDTV 2160P

33 4096*2160p 53.95 23.98 296.70 UDTV 2160P

34 4096*2160p 54 24.00 297 UDTV 2160P

35 4096*2160 56.25 25.00 297 UDTV 2160P

36 4096*2160 61.43 29.97 296.70 UDTV 2160P

37 4096*2160 67.5 30.00 297 UDTV 2160P

38 4096*2160 112.5 50.00 594 UDTV 2160P

39 4096*2160 134.86 59.94 593.40 UDTV 2160P

40 4096*2160 135 60.00 594 UDTV 2160P

Spec. out but display

- 8 -

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.

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

(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

(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

- 9 -

1. Main SoC

MAIN Audio AMP

M16+

IF+, IF-

OPTIC

LAN

HDMI1 HDMI 2.0

EEPROM(NVRAM)

PHY3_RX0N

Air/

Cable

TUNER

(C/A )

T2

DEMOD

(T2/S2 )

USB1 (2.0)

eMMC

Sub Micom

P_TS

X_TAL

T2/C/ W/O AD

X_TAL

I2S Out

I2C 0

I2C 4

R

E

A

R

YPbPr

SPDIF OUT

ETHERNET

I2C 1

SUB

ASSY

IR / KEY

LOGO LIGHT(Ready)

WIFI/BT Combo

USB_WIFI

CVBS

HDMI3 HDMI 2.0

USB2 (2.0)

RS232C/HP

HDMI2(ARC) HDMI 2.0

AV

EPI 3G/1.5G

OCP

USB2.0_2_DM1

USB2.0_3_DM0

PHY2_RX0N

PHY1_RX0N

I2C6

SIF

HDMI4 HDMI 2.0

PHY0_RX0N

PMIC

GAMMA IC

CVBS/COMP

M0

M1

DDR3 512MB*2

DDR3 256MB*2

I2C

5

V x 1 only

I2C2

V x 1

Block Diagram

- 10 -

2. I2C

SCL0

SDA0

100Ω

3.3KΩ

IC101

+3.3V_NORMAL

3.3KΩ

33Ω

IC102

EEPROM

+3.3V_NORMAL

IC5800

AUDIO AMP

SCL2

SDA2

TUNER

SCL4

SDA4

33pF

SCL5

SDA5

1.8KΩ

SCL1

SDA1

IC3000

MICOM

33Ω

3.3KΩ

+3.3V_NORMAL

3.3KΩ

+3.3V_NORMAL

IC9200

PMIC

33Ω

IC9400

GAMMA IC

33Ω

47pF

+3.3V_TU

- 11 -

3. Power

LDO DCDC

+

D13V

+5V_NORMAL

IC1600 / 4A

IC1400 / 3A

Q1100

IC1700 / 4A

AUDIO AMP

DDR3

+

3.3V_NORMAL

+3. 5V_ST

+1.8V_IO

IC2100 / 3A

+0.9V_CPU

IC2000 / 10A

+0.9V_CORE

+A13V

USB1 (2.0)

USB2 (2.0)

PANEL

IC1500 / 3. 5A

S

Y8823

1.5V_DDR

MICOM

IR_KEY

ETHERNET

WIFI

+3.5V_WOL

WIFI_EN

CPU_1V0

MAIN IC

Main

IC6900 / 2A

IC1800 / 3A

SWITCH

+0. 9V_DDR

MAIN IC

NVRAM

H/ P AMP

1.2V_DEMOD

TUNER

AUDIO AMP

MAX3232CDR

IC2200 / 2A

IC2300 / 2A

+AVDDT_EPI_C4TX

MAIN IC

- 12 -

4. Tuner

SCL5 [ GPIO73]

S

DA5[ GPIO72]

D

MD_ADC_INP DMD_ADC_INN

A

AD_ADC_SIF

[ +3.3V_TUNER] 11

[

IF_P] 8

[

IF_N] 7

[

FE_DEMOD1_1_TS_CLK] 15

[

FE_DEMOD1_TS_SYNC] 16

[

FE_DEMOD1_TS_VAL] 17

F

E_DEMOD1_TS_DATA[ 0] 18 FE_DEMOD1_TS_DATA[ 1] 19 FE_DEMOD1_TS_DATA[ 2] 20 FE_DEMOD1_TS_DATA[ 3] 21 FE_DEMOD1_TS_DATA[ 4] 22 FE_DEMOD1_TS_DATA[ 5] 23 FE_DEMOD1_TS_DATA[ 6] 24 FE_DEMOD1_TS_DATA[ 7] 25

+3. 3V_TU

[ I2C_SCL5_TU] 1

[

I2C_SDA5_TU] 2

[

TU_SIF_TU] 6

[

TU_CVBS_TU] 4

[

IF_AGC_TU] 5

[

/ TU_RESET1_TU] 10

FILTER

FE_DEMOD1_TS_CLK

F

E_DEMOD1_TS_SYNC FE_DEMOD1_TS_VAL

F

E_DEMOD1_TS_DATA [ 0- 7]

33 Ω

IF_P_TU

I

F_N_TU

T

U_CVBS

I

F_AGC

I

F_P_MAIN

I

F_N_MAIN

/ TU_RESET1

GPIO26

C

VBS_IN1

I

FAGC

+3.3V_TU

1.8 KΩ

IC101

TP_DVB_CLK

T

P_DVB_SOP TP_DVB_VAL TP_DVB_DATA0 TP_DVB_DATA1 TP_DVB_DATA2 TP_DVB_DATA3 TP_DVB_DATA4 TP_DVB_DATA5 TP_DVB_DATA6 TP_DVB_DATA7

[

3.3V_TU] 3

[ +D_Demod_Core] 13

+1. 2V Demod Core

TUNER

- 13 -

5. Video/Audio

IC101

CVBS_IN2

Tuner

Jack Side

SoC Side

JK3400

AV_CVBS_IN

COMP2_Pb

COMP2_Pr

COMP2/AV_L_IN

COMP2/AV_R_IN

AV1_CVBS_IN_SOC

COMP2_Pb_IN_SOC

COMP2_Pr_IN_SOC

AUAD_L_CH2_IN

AUAD_R_CH2_IN

TU_CVBS_TU

TU_SIF_TU, IF_P/N_TU

CVBS_IN1

AAD_ADC_SIF, DMD_ADC_INP, DMD_ADC_INN

TU_CVBS

TU_SIF, IF_P/N

FE_DEMOD1/2_TS_CLK,SYNC,VAL

[TP0CLK ,VLD,SYNC]

AUAD_R_CH2_IN

VIN3P

VIN5P

COMP2_Y

Y1_IN

COMP2_Y_IN_SOC

- 14 -

6. I2C Map

SPDIF_OUT

IC5300

A

udio AMP

LPF

IEC958OUT

Tune

r

TR BUF

A

AD_ADC_SIF

HP_LOUT / HP_ROUT

H

EAD PHONE

LPF

AUDA_OUTL_CH1

A

UDA_OUTR_CH1

TUNER_SIF

IC3000

MICOM

AMP_MUT

E

GPIO23

AMP_RESET_N

JK3403

JK6200

LPF

Front_L

Front_R

DACSCK/ GPIO81

IC101

JK3400

COMP2/AV_R_IN

COMP2/AV_L_IN

AUAD_R_CH1_IN

AUAD_L_CH2_IN

SDA0/GPIO138

S

CL0/ GPIO139

AUD_LRCK

A

UD_LRCH

IC6300

H/ P AMP

I2C_SDA_0_AMP1 / I2C_SCL_0_AMP1

DACLRCH/ GPIO82

D

ACLRCK

AUD_SCK

S

IDE_HP_MUTE

- 15 -

7. EPI block (PMIC)

HDMI4 (Rear)

H

DMI 2.0

HDMI2 (SIDE) with ARC

H

DMI 2.0

C

EC_RE

MOTE

MICOM(IC3000)

I

C101

HDMI_ARC

X- Tal(X3000)

3

2.768kHz

HDMI1 (SIDE)

H

DMI2.0

DDC_SCL_1

D

DC_SDA_1

T

MDS Link 8bits

DDC_SCL_2

D

DC_SDA_2

T

MDS Link 8bits

DDC_SCL_4

D

DC_SDA_4

* TMDS Link 8bits = TMDS DATA 6bits(DATA0,1,2)+ TMDS CLK 2bits

TMDS Link 8bits

HDMI_CEC_MICOM

Q3001

DDC_SCL_1

DDC_SDA_1

J

K3104

J

K3102

J

K3101

HDMI3

(

Rear)

H

DMI2.0

JK3103

DDC_SCL_3

D

DC_SDA_3

T

MDS Link 8bits

DDC_SCL_2

DDC_SDA_2

PHY0_ARC_OUT

DDC_SCL_3

DDC_SDA_3

DDC_SCL_4

DDC_SDA_4

- 16 -

8. USB / WIFI / M-REMOTE / UART

USB2(REAR)

USB2.0_2_DP1

USB2.0_2_DM1

GPIO94

GPIO95

USB2_0_DM0

USB2_0_DP0

USB1(SIDE)

USB2.0_2_DP1

USB2.0_2_DM1

IC1600

5V / 4A

+5V_USB_3

+5V_USB_2

/USB_OCD2

USB_CTL2

/USB_OCD2

WIFI_DM

WIFI_DP

USB2_2_DM0

USB2_2_DP0

MICOM(IC3000)

UART0_TXD/GPIO105

UART0_RXD/GPIO106

SOC_TX

SOC_RX

IC7200

USB2.0

WIFI Combo

BT_RESET

BT_WAKEUP_DEVICE

BT_WAKEUP_HOST

OCP

IC4700

OCP

IC4501

+5V_NORMAL

JK4400

JK4600

USB2.0

IC101

USB2_1_DM0

USB2_1_DP0

SPI_CS1/GPIO32

SPI_DI1/GPIO35

- 17 -

9. EPI 60Pin Interface (60Hz/3Gbps)

TX 6 lane

IC101

PMIC

IC9200

Boost IC

IC9300

VCORE

VCC18

HVDD

VDD_EPI

VCOM1

VCOMLFB

VCOM2

VGL1

VST

GIP_RST

LS_VGL

VGH_EVEN

VGH_ODD

VGH

10

CLK[1:10]

GMA1,4,5,6,9,10,13,14,15,18

10

PM_VCC

SDA2/GPIO78

SCL2/GPIO79

I2C_SDA_BACKEND

I2C_SCL_BACKEND

VDD_EPI

VCORE

SWG

SWO

SWI

PM_VCC

VCC18

PANEL_VCC

E0

GST

MCLK

GCLK

PANEL_VCC

- 18 -

10. CEDS 68Pin Interface (60Hz/1.5Gbps)

TX 12lane

IC101

PMIC

IC9200

Boost IC

I

C9300

VCORE

VCC18

HVDD

VDD_EPI

VCOM1

VCOMLFB

VCOM2

VGL1

VST

GIP_RST

LS_VGL

VGH_EVEN

VGH_ODD

VGH

6

CLK[1:6]

GMA1,5,6,,9,10,13,14,18

8

GMA2,3,4,7,8,11,12,15,16,1

7

SDA2/GPIO78

SCL2/GPIO79

I2C_SDA_BACKEND

I

2C_SCL_BACKEND

VDD_EPI

VCORE

SWG

SWO

SWI

PM_VCC

VCC1

8

PANEL_VCC

E0

GST

MCLK

G

CLK

GAMMA IC

IC9400

10

HVDD

VDD_EPI

3.3V_NORMAL

PM_VCC

PANEL_VCC

- 19 -

EXPLODED VIEW

200

400

540

521

120

820

LV1

530

901

902

121

911

500

570

411

912

710

200A

200T

700

A10

AR1

ARC1

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.

- 20 -

DISASSEMBLY GUIDE

(1) M4*20 6EA Disassemble screw

 Remove the stand

(1)

StandStand

- 21 -

(2) M3*5.5 14EA Disassemble s cre w (3) M4*10 5EA Disassemble screw (4) M8*10 4EA Disassemble screw

 Remove the Power Cord Bracket and B/Cover

(2)

(2) (2) (2)

(2)

(3) (3)

(3)

(4)

(4) (4)

B/Cover

Power Cord Bracket

- 22 -

(5) M4*10 4EA Disassemble screw (6) Detach the tape 3EA (7) Separate connector 1EA

 Remove the Bottom Cover

(5)

Bottom Cover

(6)

(7)

- 23 -

ac Combo PCB

Bottom Bracket Assy

push

(9) Push side and raise up.  Remove the ac Combo PCB

(8) Separate connector 2EA

(8)

(9)

IR Assy

(10) Pushing red point and pull out side.  Remove the IR Assy

(10)

- 24 -

(11) M 3*5.5 8EA Dis a s s e mble screw (12) Separate connector 6EA

 Remove the Main PCB Assy and Power PCB

(11)

(12)

Main PCB Assy

Power PCB

- 25 -

b

a a

b

a

(13) Separate connector 3EA  Remove the speaker 2ea

(13)

- 26 -

(14) M4*12 4EA Disassemble screw  Remove the stand Supporter 2EA (15) Detach the tape 2EA (16) Detach the Insulation Sheet 1EA

(14)

Stand Supporter

(15) (15)

(16)

(17) Detach the foot rubber

(17) (17)

- 27 -

TROUBLE SHOOTING GUIDE

Contents of Standard Repair Process

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

1

2 No video/No audio 2

3 Picture broken/ Freezing 3

4 Color error 4

5

6

7

8

9 Wrecked audio/discontinuation/noise 10

10

11

A. Video error

B. Power error

C. Audio error

No video/Normal audio 1

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

No power 6

Off when on, off while viewing, power

auto on/off

No audio/Normal video 9

Remote control & Local switch checking

MR15 operating checking 12

5

7-8

11

12

13 Camera operating checking 14

14 External device recognition error 15

15 E. Noise Circuit noise, mechanical noise 16

16 F. Exterior error Exterior defect 17

D. Function error

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

Wifi operating checking 13

Standard Repair Process

symptom

Error

A. Video error

No video/ Normal audio

Established

date

Revised date

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

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

☞A18 ☞A1

No video Normal audio

Normal

audio

N

Move to No video/No audio

Y

Check Back Light On with naked eye

☞A18

On

Check Power Board 13V output

Normal voltage

Repair Power Board or parts

Y N Check Power

Y

N

Board 13V

Replace Inverter or module

Normal

voltage

N

Repair Power Board or parts

End

Replace T-con/Main

Y

Board or module

1/17

※Precaution

Always check & record S/W Version and White Balance value before replacing the Main Board

☞A4 & A2

Replace Main Board

1

Re-enter White Balance value

LG 75UJ657, 75UJ64*0 Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual