LG DP-471B User manual

P/NO : AFN73065036 APRIL, 2009
PORTABLE DVD
SERVICE MANUAL
MODEL : DP471B/DP472B/DP473B
CAUTION
BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.
Website http://biz.lgservice.com
Internal Use Only
MODEL : DP471B/DP472B/DP473BSERVICE MANUAL

1-1
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
CONTENTS
SECTION 1.........SUMMARY
SECTION 2.........EXPLODED VIEWS
SECTION 3.........ELECTRICAL
SECTION 4.........REPLACEMENT PARTS LIST

1-2 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SECTION 1
SUMMARY
CONTENTS
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS .............................................. 1-3
SERVICING PRECAUTIONS .......................................................................................................................... 1-4
• GENERAL SERVICING PRECAUTIONS
• INSULATION CHECKING PRODEDURE
• ELECTROSTATICALLY SENSITIVE (ES) DEVICES
SPECIFICATIONS............................................................................................................................................ 1-5

1-3
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO 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 des-
ignators 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: Do not attempt to modify this product in any way. Never perform cus-
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.
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 equi-
lateral 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 par-
ticles.
4. Check for physical evidence of damage or deterioration to parts and compo-
nents, 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 volt-
age 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 measure-
ments 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 instal-
lations.
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 exten-
sions, sprouting from a single outlet, can lead to disastrous consequences to
home and family.

1-4 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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 publica-
tion, 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 electro-
lytic 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 elec-
trical 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.
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.
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 compo-
nent or semiconductor-equipped assembly, drain off any
electrostatic charge on your body by touching a known
earth ground. Alternatively, obtain and wear a commer-
cially 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.
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 elec-
tricity sufficient to damage an ES device.)

1-5
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SPECIFICATIONS
• DVD PLAYER
Power requirements DC 9 ~ 15V
Power consumption 13W
External dimensions 202 x 44 x 165mm (W x H x D)
Net weight (Approx.) 0.82kg
Operating temperature 0°C to 45°C
Operating humidity 0% to 60%
Laser semiconductor laser
Signal system PAL/NTSC
• CONNECTORS
Audio/Video Output ø3.5mm mini jack x 1
- Video: 1.0V(p-p), 75Ω, sync negative
- Audio: 2Vrms (1kHz, 0dB)
Earphone terminal ø3.5mm stereo mini jack x 2
USB 2.0 Type:A
• 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 (Cu-2993)
Remote Control
Battery for Remote Control (Lithium Battery)

1-6 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
MEMO

2-1
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SECTION 2
EXPLODED VIEWS
CONTENTS
EXPLODED VIEWS ......................................................................................................................................... 2-2
1. CABINET AND MAIN FRAME SECTION ................................................................................................. 2-2
2. PACKING ACCESSORY SECTION ......................................................................................................... 2-3

2-2 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
A
LCD
BOARD
LCD
PANEL
MAIN
BOARD
C
A
B
ED
B
CED
475
279
278
277
476
277
477
477
477
477
474
474
271
477
251
272
A48
A40
262
264
475
263
260
262
262
809
265
282
289
284
287
283
283
288
288
290
286
285
478 280
281
280
475
475
475
A44
A00
A53
A46
A43
A52
A51
CABLE3
SVC purchase order caution
Cables must be ordered assembly part.
Supply is possible in Location No. 278,
A40 and A53.
EXPLODED VIEWS
1. CABINET AND MAIN FRAME SECTION

2-3
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
2. PACKING ACCESSORY SECTION
803 PACKING
839
PLUG ASS'Y(RCA CABLE)
806
834
ADAPTER
833
REMOTE CONTROL
900
CARRING CASE
BOX
802
801 OWNER'S MANUAL
CABLE, CIGAR JACK
804 PACKING SHEET
835 CAR-MOUNT
808 BATTERY

2-4 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
MEMO

3-1
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
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. ..................................................................3-9
2. SDRAM CLOCK...................................................................................................................................3-11
3. TRAY OPEN/CLOSE SIGNAL.............................................................................................................3-11
4. SLED CONTROL RELATED SIGNAL .................................................................................................3-12
5. LASER POWER CONTROL RELATED SIGNAL ................................................................................3-13
6. SPINDLE CONTROL WAVEFORM.....................................................................................................3-13
7. FOCUS ON WAVEFORM....................................................................................................................3-14
8. TRACKING CONTROL RELATED SIGNAL(SYSTEM CHECKING)...................................................3-15
9. VIDEO OUTPUT WAVEFORM............................................................................................................3-16
10. AUDIO OUTPUT ..................................................................................................................................3-16
WIRING CONNECTION DIAGRAM ....................................................................................................3-17
BLOCK DIAGRAMS ................................................................................................................................3-18
1. OVERALL BLOCK DIAGRAM .............................................................................................................3-18
2. SYSTEM BLOCK DIAGRAM ...............................................................................................................3-19
3. DC BLOCK DIAGRAM.........................................................................................................................3-20
CIRCUIT DIAGRAMS ..............................................................................................................................3-27
1. LCD I/F CIRCUIT DIAGRAM ...............................................................................................................3-21
2. OPU CIRCUIT DIAGRAM....................................................................................................................3-23
3. HP/SPK AMP CIRCUIT DIAGRAM......................................................................................................3-25
4. AUDIO I/F CIRCUIT DIAGRAM ...........................................................................................................3-27
5. MOTOR DRIVE CIRCUIT DIAGRAM ..................................................................................................3-29
6. MEMORY CIRCUIT DIAGRAM............................................................................................................3-31
7. MPEG CIRCUIT DIAGRAM .................................................................................................................3-33
8. VIDEO CONTROLER CIRCUIT DIAGRAM.........................................................................................3-35
9. AV I/F CIRCUIT DIAGRAM..................................................................................................................3-37
10. USB I/F CIRCUIT DIAGRAM ...............................................................................................................3-39
11. LCD POWER CIRCUIT DIAGRAM......................................................................................................3-41
12. MPEG POWER CIRCUIT DIAGRAM ..................................................................................................3-43
13. INPUT POWER CIRCUIT DIAGRAM ..................................................................................................3-45
14. B/L POWER CIRCUIT DIAGRAM........................................................................................................3-47
15. CHARGER POWER CIRCUIT DIAGRAM ...........................................................................................3-49
16. SWITCH & VIDEO BUFFER CIRCUIT DIAGRAM ..............................................................................3-51
CIRCUIT VOLTAGE CHART ...........................................................................................................3-53
PRINTED CIRCUIT BOARD DIAGRAMS.........................................................................................3-57
1. MAIN P.C. BOARD ..............................................................................................................................3-57
2. LCD P.C. BOARD ................................................................................................................................3-57

3-2 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
ELECTRICAL TROUBLESHOOTING GUIDE
No 1.8V
Replace U16
NO
1. POWER CHECK FLOW
A. B.
Is
3.3V section
working?
YES
YES
Replace C19,C23
No 5V or 3.3V
Replace
D5, Q11, Q16, Q19
NO
Check
VCC_ADP
YES

3-3
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
2. SYSTEM OPERATION FLOW
Power on
1. 8032 initializes SERVO,DSP & RISC registers
2. Write RISC code to SDRAM
3. Reset RISC
Show LOGO
SLED moves to inner position
1. Judge whether have disc and disc type
2. Jump to related disc reading procedure
1. Execute pressed Key & IR key
2. System operation routine loop
1. Stop playback & open Tray
2. Display tray open message & LOGO
NO
NO
YES
NO
NO
Tray closed?
Tray at closed
position
Received
function key
Sled motor
at inner side?
Tray open

3-4 Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
3. SYSTEM TEST FLOW
TEST Start
Repair short problem.
YES
NO
Switch power on
Flash upgrade
Repair DC output problem.
YES
NO
1. Check code version
2. Check Crystal clock is 27MHz
3. Check SDRAM clock.
4. Check reset circuit.
5. Check debug setting.
NO
A
OK
Make sure
PCBA no short. Especially
power block.
Is
the DC voltage correct?
DC 5V,3.3V,1.8V

3-5
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
RESET or power on.
Plug AV-Cable in
NO NO
YES
NO
YES
Check component value.
1. Check video relate setting of
chip circuit.
2. Check Main chip.
NO
YES
Check open, short,
direction, pin definition.
1. Check panel & panel board
circuit.
2. Check TV system.
YES
YES
LOGO
display?
NO
LOGO
display on TV?
Check 8202T
Video out
Check
video circuit
Check cable &
connection wire.
A
B

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NONO
NO
YES
1. Check SW signal.
2. Check circuit between
SW & IC.
NO
YES
Check motor driver
related circuit.
1. Check OPU protection.
2. Check laser on power circuit.
Check cable connection
between PCB & Traverse.
Play Disc
Reading disc
YES
YES
Check tact
switch of cover?
Check DC voltage
of SLED+, -?
Check SLED
motor moves to inner
from outer side when
power on?
Laser on?
NO
Check disc type.
YES
YES
Read disc?
B
C

3-7
Copyright © 2009 LG Electronics. Inc. All right reserved.
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C
D
Audio feature verification.
Plug AV-Cable in
Plug headphone in
Line out
function normal?
Speaker out
normal?
1. Check mute
control signal.
2. Check U12 setting. Pin15-
Shutdown, Pin21-Volume,
Pin22-HP/LINE,
Pine23-SE/BTL
NO
Check 8202T
DAC out
NO
NO
NO
YES
YES
Check Audio
peripheral circuit
1. Check audio
relate circuit of
main chip.
2. Check Main chip.
Check
component value.
NO
YES
Check cable
YES
Headphone
out normal?
1. Check earphone
peripheral circuit.
2. Check U12 setting.
Pin22-HP/LINE,
Pine23-SE/BTL
NO NO
YES
YES
Check Jack,
connector
Check open,
short, direction,
pin define.
NO
YES
YES
YES

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NO
NO
NO
YES
Check USB power.
YES
YES
USB feature.
USB playing.
USB detection? USB
driver power?
NO 1. Check differential signal.
2. Check related circuit.
USB signal?USB file play?
D

3-9
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
RESET_B
+3.3V_SYS
C106
NC U10
G692L263TCUF
23
14
RST MR
GND VCC
+1.8V_SYS
C22
0.1U/25V/0402
L4
0/J/0603
C23
10U/6.3V/0805
C17
NC/10U/6.3V/0805
U16
LD1117AL-1.8V/SOT-223
2
1
3
4
VO
GND
VIN
VO2
Close IC
CLKOUT
CLKIN
R65
0/J/0402
C81
33P/50V/0402
Y2
27M/49US/DIP
R60
0/J/0402
R58
4.7K/F/0402
C71
33P/50V/0402
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING
1. SYSTEM 27MHz CLOCK, RESET, FLASH SCK SIGNAL.
1-1. Main clock is at 27MHz(Y2)
1-2. Reset is active high.
FIG 1-1
1
FIG 1-2
2
3
3
2
1