LG DP461A Service manual

PORTABLE DVD

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

SERVICE

MANUAL

MODEL: DP461A

Internal Use Only

Website http://biz.lgservice.com

MODEL: DP461A

P/NO : AFN73290714 AUGUST, 2009

CAUTION

CONTENTS

SECTION 1.........SUMMARY

SECTION 2.........EXPLODED VIEWS

SECTION 3.........ELECTRICAL

SECTION 4.........REPLACEMENT PARTS LIST

1-1

SECTION 1

SUMMARY

CONTENTS

PRODUCT SAFETY SERVICING GUIDELINES FOR PORTABLE DVD PRODUCTS.........1-3

SERVICING PRECAUTIONS....................................................................................................................1-4

• GENERAL SERVICING PRECAUTIONS

• INSULATION CHECKING PRODEDURE

• ELECTROSTATICALLY SENSITIVE (ES) DEVICES

SPECIFICATIONS ........................................................................................................................................1-5

1-2

PRODUCT SAFETY SERVICING GUIDELINES FOR PORTABLE DVD PRODUCTS

IMPORTANT SAFETY NOTICE

This manual was prepared for use only by properly trained audio-video service tech­nicians.
When servicing this product, under no circumstances should the original design be
modified or altered without permission from LG Corporation. All components should
be replaced only with types identical to those in the original circuit and their physical
location, wiring and lead dress must conform to original layout upon completion of
repairs.

Special components are also used to prevent x-radiation, shock and fire hazard.
These components are indicated by the letter “x” included in their component desig­nators and are required to maintain safe performance. No deviations are allowed
without prior approval by LG Corporation.
Circuit diagrams may occasionally differ from the actual circuit used. This way, imple­mentation of the latest safety and performance improvement changes into the set are
not delayed until the new service literature is printed.

CAUTION

tomized installations without manufacturer’s approval. Unauthorized modifications will
not only void the warranty, but may lead to property damage or user injury.

Service work should be performed only after you are thoroughly familiar with these
safety checks and servicing guidelines.

: Do not attempt to modify this product in any way. Never perform cus-

GRAPHIC SYMBOLS

The exclamation point within an equilateral triangle is intended to alert
the service personnel to important safety information in the service lit­erature.
The lightning flash with arrowhead symbol within an equilateral trian­gle is intended to alert the service personnel to the presence of non­insulated “dangerous voltage” that may be of sufficient magnitude to
constitute a risk of electric shock.
The pictorial representation of a fuse and its rating within an equilater­al triangle is intended to convey to the service personnel the following
fuse replacement caution notice:
CAUTION: FOR CONTINUED PROTECTION AGAINST RISK OF
FIRE, REPLACE ALL FUSES WITH THE SAME TYPE AND RAT­ING AS MARKED NEAR EACH FUSE.

SERVICE INFORMATION

While servicing, use an isolation transformer for protection from AC line shock. After
the original service problem has been corrected, make a check of the following:

FIRE AND SHOCK HAZARD

1. Be sure that all components are positioned to avoid a possibility of adjacent com­ponent shorts. This is especially important on items trans-ported to and from the
repair shop.

2. Verify that all protective devices such as insulators, barriers, covers, shields, strain
reliefs, power supply cords, and other hardware have been reinstalled per the orig­inal design. Be sure that the safety purpose of the polarized line plug has not been
defeated.

3. Soldering must be inspected to discover possible cold solder joints, solder splash­es, or sharp solder points. Be certain to remove all loose foreign particles.

4. Check for physical evidence of damage or deterioration to parts and components,
for frayed leads or damaged insulation (including the AC cord), and replace if nec­essary.

5. No lead or component should touch a high current device or a resistor rated at 1
watt or more. Lead tension around protruding metal surfaces must be avoided.

6. After reassembly of the set, always perform an AC leakage test on all exposed
metallic parts of the cabinet (the channel selector knobs, antenna terminals, han­dle and screws) to be sure that set is safe to operate without danger of electrical
shock. DO NOT USE A LINE ISOLATION TRANSFORMER DURING THIS
TEST. Use an AC voltmeter having 5000 ohms per volt or more sensitivity in the
following manner: Connect a 1500 ohm, 10 watt resistor, paralleled by a .15 mfd
150V AC type capacitor between a known good earth ground water pipe, conduit,
etc.) and the exposed metallic parts, one at a time. Measure the AC voltage across
the combination of 1500 ohm resistor and .15 mfd capacitor. Reverse the AC plug
by using a non-polarized adaptor and repeat AC voltage measurements for each
exposed metallic part. Voltage measured must not exceed 0.75 volts RMS. This
corresponds to 0.5 milliamp AC. Any value exceeding this limit constitutes a poten­tial shock hazard and must be corrected immediately.

TIPS ON PROPER INSTALLATION

1. Never install any receiver in a closed-in recess, cubbyhole, or closely fitting shelf
space over, or close to, a heat duct, or in the path of heated air flow.

2. Avoid conditions of high humidity such as: outdoor patio installations where dew
is a factor, near steam radiators where steam leakage is a factor, etc.

3. Avoid placement where draperies may obstruct venting. The customer should also
avoid the use of decorative scarves or other coverings that might obstruct ventila­tion.

4. Wall- and shelf-mounted installations using a commercial mounting kit must follow
the factory-approved mounting instructions. A product mounted to a shelf or plat­form must retain its original feet (or the equivalent thickness in spacers) to provide
adequate air flow across the bottom. Bolts or screws used for fasteners must not
touch any parts or wiring. Perform leakage tests on customized installations.

5. Caution customers against mounting a product on a sloping shelf or in a tilted posi­tion, unless the receiver is properly secured.

6. A product on a roll-about cart should be stable in its mounting to the cart.
Caution the customer on the hazards of trying to roll a cart with small casters
across thresholds or deep pile carpets.

7. Caution customers against using extension cords. Explain that a forest of exten­sions, sprouting from a single outlet, can lead to disastrous consequences to
home and family.

1-3

SERVICING PRECAUTIONS

CAUTION: Before servicing the PORTABLE DVD covered by
this service data and its supplements and addends, read and
follow the SAFETY PRECAUTIONS. NOTE: if unforeseen cir­cumstances create conflict between the following servicing
precautions and any of the safety precautions in this publica­tion, always follow the safety precautions.
Remember Safety First :

General Servicing Precautions

1. Always unplug the PORTABLE DVD AC power cord from
the AC power source before:
(1) Removing or reinstalling any component, circuit board,

module, or any other assembly.

(2) Disconnecting or reconnecting any internal electrical

plug or other electrical connection.

(3) Connecting a test substitute in parallel with an electrolyt-

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

2. Do not spray chemicals on or near this PORTABLE DVD or
any of its assemblies.

3. Unless specified otherwise in this service data, clean elec­trical contacts by applying an appropriate contact cleaning
solution to the contacts with a pipe cleaner, cotton-tipped
swab, or comparable soft applicator.
Unless specified otherwise in this service data, lubrication of
contacts is not required.

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

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

6. Always connect the test instrument ground lead to an appro­priate ground before connecting the test instrument positive
lead. Always remove the test instrument ground lead last.

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 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 for 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 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
an electrical charge 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.

Insulation Checking Procedure

Disconnect the attachment plug from the AC outlet and turn
the power on. Connect an insulation resistance meter (500V)
to the blades of the attachment plug. The insulation resistance
between each blade of the attachment plug and accessible
conductive parts (Note 1) should be more than 1Mohm.
Note 1: Accessible Conductive Parts include Metal panels,
Input terminals, Earphone jacks,etc.

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. (Normally 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.)

1-4

SPECIFICATIONS

• GENERAL

Power requirements DC 12V

Power consumption 12W

External dimensions 207 x 39 x 168mm (W x H x D)

Net weight (Approx.) 0.85kg

Operating temperature 5°C to 40°C

Operating humidity 5% to 90%

Laser Semiconductor laser

Signal system NTSC,PAL

• CONNECTORS

Audio/Video Output ø3.5mm mini jack x 1

- Video: 1.0V(p-p), 75Ω, sync negative

- Audio: 1.5Vrms (1kHz, 0dB)

Earphone terminal ø3.5mm stereo mini jack x 2

Antenna Input 75 ohms (VHF/UHF)

Channel coverage Analog (VHF: 2-13, UHF: 14-69, CATV: 1-135)

Digital (Terrestrial: 2-69, Cable: 1-135)

• LIQUID CRYSTAL DISPLAY

Panel size 7 inches wide (diagonal)

Projection system R.G.B. stripe

Driving system TFT active matrix

Resolution 480 x 234 (WQVGA)

• ACCESSORIES

- RCA Video/Audio cable

- AC Adapter (MPA-630)

- Automotive Adapter (DPDC1)

- Remote Control

- Battery for Remote Control (Lithium Battery)

- Antenna cable

- By-pack telescopic antenna

1-5

MEMO

1-6

SECTION 2

EXPLODED VIEWS

CONTENTS

EXPLODED VIEWS .....................................................................................................................................2-2

1. CABINET AND MAIN FRAME SECTION ..................................................................................................2-2

2. PACKING ACCESSORY SECTION...........................................................................................................2-3

2-1

EXPLODED VIEWS

296

CABLE8

A00

1. CABINET AND MAIN FRAME SECTION

G

CABLE3

295

263

262

CABLE2

M

279

262

F

E

L

CABLE10

K

278

289

809

E

A44

M

D

L

K

G

MAIN

F

BOARD

260

266

266

A46

269

J

CABLE9

I

H

285

284

283

261

287

C

CABLE1

282

C

281

D

A45

KEY

BOARD

A53

A48

293

B

A43

A

264

265

0
A4

A

H

286

288

285

277

A51

LCD

BOARD

A52

I

252

253

251

277

J

B

A41

BOARD

INVERTER

251A

272

2-2

2. PACKING ACCESSORY SECTION

837

TUNER, ANALOG

811

RF CABLE

834

CABLE, CIGAR JACK

806

PLUG ASS'Y(RCA CABLE)

833

ADAPTER

900

REMOTE CONTROL

838

ANTENNA, BAR

808

801

OWNER'S MANUAL

804

PACKING SHEET

803

BATTERY

PACKING

802A

BOX(SWM3)

802

MASTER BOX(DW)

802B

BOX(ACCESSORY)

2-3

MEMO

2-4

SECTION 3

ELECTRICAL

CONTENTS

ELECTRICAL TROUBLESHOOTING GUIDE ...................................................................................3-2

1. POWER CHECK FLOW.........................................................................................................................3-2

2. SYSTEM OPERATION FLOW ...............................................................................................................3-3

3. SYSTEM TEST FLOW ..........................................................................................................................3-4

DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING .................................3-11

1. SYSTEM 27MHZ CLOCK, RESET, FLASH SCK SIGNAL. .................................................................3-11

2. SDRAM CLOCK ...................................................................................................................................3-13

3. TRAY OPEN/CLOSE SIGNAL..............................................................................................................3-13

4. SLED CONTROL RELATED SIGNAL ..................................................................................................3-14

5. LASER POWER CONTROL RELATED SIGNAL .................................................................................3-15

6. SPINDLE CONTROL WAVEFORM......................................................................................................3-15

7. FOCUS ON WAVEFORM.....................................................................................................................3-16

8. TRACKING CONTROL RELATED SIGNAL(System checking) ...........................................................3-17

9. 1389P VIDEO OUTPUT WAVEFORM .................................................................................................3-18

10. AUDIO OUTPUT FROM 1389P ...........................................................................................................3-18

WIRING CONNECTION DIAGRAMS..................................................................................................3-19

1. WIRING CONNECTION DIAGRAM-1..................................................................................................3-19

2. WIRING CONNECTION DIAGRAM-2..................................................................................................3-20

BLOCK DIAGRAMS.................................................................................................................................3-21

1. OVERALL BLOCK DIAGRAM..............................................................................................................3-21

2. POWER BLOCK DIAGRAM.................................................................................................................3-22

3. SERVO BLOCK DIAGRAM..................................................................................................................3-23

4. SYSTEM BLOCK DIAGRAM................................................................................................................3-24

5. AV BLOCK DIAGRAM ..........................................................................................................................3-25

6. LCD BLOCK DIAGRAM .......................................................................................................................3-26

CIRCUIT DIAGRAMS ..............................................................................................................................3-27

1. MPEG CIRCUIT DIAGRAM .................................................................................................................3-27

2. MEMORY CIRCUIT DIAGRAM............................................................................................................3-29

3. OPU & MOTOR CIRCUIT DIAGRAM ..................................................................................................3-31

4. AV CIRCUIT DIAGRAM........................................................................................................................3-33

5. CHARGE CIRCUIT DIAGRAM.............................................................................................................3-35

6. LCD IF CIRCUIT DIAGRAM.................................................................................................................3-37

7. TUNER CIRCUIT DIAGRAM................................................................................................................3-39

8. MENU KEY CIRCUIT DIAGRAM .........................................................................................................3-41

9. LED DRIVER CIRCUIT DIAGRAM ......................................................................................................3-43

10. FRONT KEY CIRCUIT DIAGRAM........................................................................................................3-45

CIRCUIT VOLTAGE CHART ............................................................................................................3-47

PRINTED CIRCUIT BOARD DIAGRAMS .........................................................................................3-51

1. MAIN P.C.BOARD ................................................................................................................................3-51

2. LCD P.C.BOARD ..................................................................................................................................3-55

3. INVERTER P.C.BOARD .......................................................................................................................3-55

4. KEY P.C.BOARD ..................................................................................................................................3-57

3-1

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER CHECK FLOW

A. B.

No 3.3VA

Is

5VA section

working?

YES

Is

VCC_5V section

working?

Check Q305/Q306

and Replace

NO

YES

Check Q303/D301

and Replace

YESNO

Replace U301

No 5VA

BAT_OUT=12V?

YES

Check Q304/D302

and Replace

YES

NO

Check

D501 Replace

3-2

2. SYSTEM OPERATION FLOW

1.

8032 initializes SERVO,DSP & RISC registers

2. Write RISC code to SDRAM

3. Reset RISC

Show LOGO

Power on

YES

SLED moves to inner position

1. Judge whether have disc and disc type

2. Jump to related disc reading procedure

Tray closed?

NO

Tray close to closed position

SLED at

inner side?

NO

Receive

OPEN/CLOSE Key?

YES

YES

1. Execute pressed Key & IR key

2. System operation routine loop

1. Stop playback & open Tray

2. Display tray open message & LOGO

NO

Receive

CLOSE Key?

NO

YES

3-3

3. SYSTEM TEST FLOW

3-1. DVD MODE TEST

TEST

Check the

AC voltage power PCBA

(110V or 220V)

YES

Switch on the power PCBA

Is the DC voltage

outputs OK? (5V, 3.3V, 12V,

5.6V MOTOR)

YES

Make sure the main PCBA don't

short on VCCs and switch it on.

YES

Is 3.3V and 1.8V DC

outputs normal on main

PCBA?

YES

NO

NO

NO

Replace power PCBA or AC transformer.

Repair or Replace power PCBA

Check the regulators or related diodes.

Connect to PC RS232 cable and

update the FLASH memory code.

Update FLASH

successfully?

YES

A

NO

1. Check 27MHz system clock.

2. Check system reset circuit.

3. Check FLASH R/W enable signal PRD,
RWR.

4. Check RS232 SIGNALS.

5. Check FLASH Memory related circuit.

3-4

A

RESET or power on.

Show LOGO?

YES

NO NO

connection to TV set.

Flash

memory operates

properly?

YES

SDRAM

works properly?

YES

138PDE/LP

VIDEO outputs

properly?

YES

Have TV

signal output?

YES

Check AV cable

NO

NO

NO

Check connection lines

between FLASH & MTK1389P

and the FLASH access time

whether is suitable or not.

Check connection lines

between SDRAM & MTK1389P

and the SDRAM is damaged.

Check the related

circuit of1389P.

Check the filtering and

amp circuit of TV signal.

Does tray

move inside when

it is not at closed

position?

YES

B

NO

OPEN_SW & CLOSE_SW

Normal

signals?

YES

Normal

OPEN & CLOSE

signal?

YES

Normal

FAN_TRAY+ & FAN_TRAY-

signal?

YES

Check the cable connection

between main PCBA and loader.

3-5

NO

NO

NO

Check the load

OPEN & CLOSE switch

Check the Tray control

IO pins on 1389P & AM5898N.

Check the Tray control

amplifying circuit on Motor driver.