LG DP372 Service Manual

PORTABLE DVD

SERVICE MANUAL

MODEL: DP372/DP372B-N

CAUTION

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

MODEL: DP372/DP372B-N

SERVICE MANUAL

P/NO : AFN56903618 MARCH , 2008

Website http://biz.lgservice.com

Internal Use Only

CONTENTS

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

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

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

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

1-1

LGE Internal Use Only

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

LGE Internal Use Only

1-2

Only for training and service purposes

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

LGE Internal Use Only

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.

LGE Internal Use Only

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

Only for training and service purposes

SPECIFICATIONS

• DVD PLAYER

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

• 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

• LIQUID CRYSTAL DISPLAY

Panel size 7inches wide (diagonal)

Projection system R.G.B. stripe

Driving system TFT active matrix

Resolution 480 x 234 (WQVGA)

• SUPPLIED ACCESSORIES

RCA Video/Audio cable

AC Adapter (MPA-630)

Automotive Adapter (DPDC1)

Remote Control

Battery for Remote Control (Lithium Battery)

1-5

LGE Internal Use Only

MEMO

LGE Internal Use Only

1-6

Only for training and service purposes

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

LGE Internal Use Only

EXPLODED VIEWS

1. CABINET AND MAIN FRAME SECTION

A00

295

CABLE3

263

CABLE2

296

809

262

279

CABLE10

78 2

89 2

CABLE

CABLE8

MAIN

BOARD

A46

A44

269

261

CABLE1

84 2

285

287

288

83 2

82 2

266

260

266

A45

RD 81 2

KEY

BOA

A53

A48

LGE Internal Use Only

293

264

265

A43

A51

A40

288

LCD

BOARD

2-2

85 2

53 2

277

A41

BOARD

INVERTER

286

277

A52

52 2

251

251A

72 2

Only for training and service purposes

2. PACKING ACCESSORY SECTION

834

CABLE, CIGAR JACK

806

PLUG ASS'Y(RCA CABLE)

808

BATTERY

833

ADAPTER

900

REMOTE CONTROL

835

801

OWNER'S MANUAL

804

PACKING SHEET

CAR-MOUNT

803

BAG

802B

802

MASTER BOX

BOX

802A

BOX

2-3

LGE Internal Use Only

MEMO

LGE Internal Use Only

2-4

Only for training and service purposes

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 .................................3-10

1. SYSTEM 27MHZ CLOCK, RESET, FLASH SCK SIGNAL. .................................................................3-10

2. SDRAM CLOCK ...................................................................................................................................3-12

3. TRAY OPEN/CLOSE SIGNAL..............................................................................................................3-12

4. SLED CONTROL RELATED SIGNAL ..................................................................................................3-13

5. LASER POWER CONTROL RELATED SIGNAL .................................................................................3-14

6. SPINDLE CONTROL WAVEFORM......................................................................................................3-14

7. FOCUS ON WAVEFORM.....................................................................................................................3-15

8. TRACKING CONTROL RELATED SIGNAL(System checking) ...........................................................3-16

9. 1389DE/LP VIDEO OUTPUT WAVEFORM .........................................................................................3-17

10. AUDIO OUTPUT FROM 1389DE/LP .................................................................................................3-17

WIRING CONNECTION DIAGRAMS..................................................................................................3-18

1. WIRING CONNECTION DIAGRAM-1..................................................................................................3-18

2. WIRING CONNECTION DIAGRAM-2..................................................................................................3-19

BLOCK DIAGRAMS.................................................................................................................................3-20

1. OVERALL BLOCK DIAGRAM..............................................................................................................3-20

2. POWER BLOCK DIAGRAM.................................................................................................................3-21

3. SERVO BLOCK DIAGRAM..................................................................................................................3-22

4. SYSTEM BLOCK DIAGRAM................................................................................................................3-23

5. AV BLOCK DIAGRAM ..........................................................................................................................3-24

6. LCD BLOCK DIAGRAM .......................................................................................................................3-25

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. AUDIO CIRCUIT DIAGRAM.................................................................................................................3-39

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

9. LCD KEY CIRCUIT DIAGRAM.............................................................................................................3-43

CIRCUIT VOLTAGE CHART ..........................................................................................................3-45

PRINTED CIRCUIT BOARD DIAGRAMS .........................................................................................3-49

1. MAIN P.C.BOARD ................................................................................................................................3-49

2. LCD P.C.BOARD ..................................................................................................................................3-53

3. INVERTER P.C.BOARD .......................................................................................................................3-53

4. KEY P.C.BOARD ..................................................................................................................................3-53

3-1

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER CHECK FLOW

A. B.

No 3.3VA

5VA section

working?

YES

VCC_5V section

working?

Check Q402/Q415

and Replace

YES

Check Q408/D401

and Replace

YESNO

Replace U401

No 5VA

BAT_OUT=12V?

YES

Check Q410/D402

and Replace

YES

Check D606

Replace

LGE Internal Use Only

3-2

Only for training and service purposes

2. SYSTEM OPERATION FLOW

8032 initializes SERVO,DSP & RISC registers

2. Write RISC code to SDRAM

3. Reset RISC

Show LOGO

Power on

YES

Tray close to closed position

SLED moves to inner position

1. Judge whether have disc and disc type

2. Jump to related disc reading procedure

Tray closed?

SLED at

inner side?

Receive

OPEN/CLOSE Key?

YES

1. Execute pressed Key & IR key

2. System operation routine loop

1. Stop playback & open Tray

2. Display tray open message & LOGO

Receive

CLOSE Key?

3-3

YES

LGE Internal Use Only

3. SYSTEM TEST FLOW

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

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.

LGE Internal Use Only

Update FLASH

successfully?

YES

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

Only for training and service purposes

RESET or power on.

Show LOGO?

YES

NO NO

Flash

memory operates

properly?

YES

SDRAM

works properly?

YES

138PDE/LP

VIDEO outputs

properly?

YES

Have TV

signal output?

YES

Check AV cable

connection to TV set.

Check connection lines between

FLASH & MTK1389DE/LP and

the FLASH access time whether

is suitable or not.

Check connection lines

between SDRAM &

MTK1389DE/LP and the

SDRAM is damaged.

Check the related circuit

of1389DE/LP.

Check the filtering and

amp circuit of TV signal.

Does tray

move inside when

it is not at closed

position?

YES

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

Check the load

OPEN & CLOSE switch

Check the Tray control IO pins

on 1389DE/LP & AM5898N.

Check the Tray control

amplifying circuit on Motor driver.

LGE Internal Use Only

+ 35 hidden pages