LG LAS450H User manual

SERVICE MANUAL
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.
Internal Use Only
Website http://biz.lgservice.com
Wireless Sound Bar
MARCH, 2015P/NO : AFN77152089
MODEL: LAS450H / LAC550H
MODEL: LAS450H / LAC550H

1-1
CONTENTS
SECTION 1 ........ GENERAL
SECTION 2 ........ CABINET & MAIN CHASSIS
SECTION 3 ........ ELECTRICAL
SECTION 4 ........ WIRELESS SUBWOOFER PART
SECTION 5 ........ REPLACEMENT PARTS LIST

1-2
SECTION 1
GENERAL
CONTENTS
ESD PRECAUTIONS......................................................................................................................................... 1-3
WIRELESS SUBWOOFER CONNECTION....................................................................................................... 1-4
HIDDEN KEY MODE ......................................................................................................................................... 1-5
MCS / EQ HIDDEN KEY GUIDE ....................................................................................................................... 1-6
MCS / EQ PROGRAM UPDATE GUIDE........................................................................................................... 1-7
SPECIFICATIONS ............................................................................................................................................. 1-8

1-3
ESD PRECAUTIONS
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD 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 ESD 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 ESD 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 ESD devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD
devices.
6. Do not remove a replacement ESD device from its protective package until immediately before you are
ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive materials).
7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the
protective material to the chassis or circuit assembly into which the device will by installed.
CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER
SAFETY PRECAUTIONS.
8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate
static electricity sufficient to damage an ESD device).
CAUTION. GRAPHIC SYMBOLS
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED
“DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF
ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE
SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.

1-4
WIRELESS SUBWOOFER CONNECTION
LED indicator of wireless subwoofer
LED Color Status
Yellow-green
(Blink) The connection is trying.
Yellow-green The connection is completed.
Red
The wireless subwoofer is
in standby mode or the
connection is failed.
Off
(No display)
The power cord of wireless
subwoofer is disconnected.
Setting up the wireless subwoofer
for the first time
1. Connect the power cord of the wireless subwoofer
to the outlet.
2. Turn on the main unit : The main unit and wireless
subwoofer will be automatically connected.
Manually pairing wireless subwoofer
When your connection is not completed, you can see
the red LED or the blinking of yellow-green LED on
the wireless subwoofer and the subwoofer does not
make sound. To solve the problem, follow the below
steps.
1. Adjust volume level of the main unit to minimum.
- “VOL MIN” appears on the display window.
2. Press and hold (Mute) on the remote control for
about 3 seconds.
- “WL RESET” appears on the display window
briefly and Red LED on the main unit is blinking.
3. If the LED of the wireless subwoofer already blinks
in yellow-green continually, you can skip this step.
Press and hold PAIRING on the back of the
wireless subwoofer for more than 5 seconds.
- The LED of the wireless subwoofer lights up
alternately in red and yellow-green.
4. Disconnect the power cord of the main unit and the
wireless subwoofer.
5. Connect them again after the LED of the main unit
and the wireless subwoofer is fully turned off.
The main unit and the wireless subwoofer will be
paired automatically when you turn on the main unit.
- When the connection is completed, you can see
the yellow-green LED on the subwoofer.
Note :
•It takes a few seconds (and may take longer) for
the main unit and the subwoofer to communicate
with each other and make sounds.
•The closer the main unit and the subwoofer, the
better sound quality. It is recommended to install
the main unit and the subwoofer as close as
possible (within 5 m) and avoid the cases below.
- There is a obstacle between the main unit and the
subwoofer.
- There is a device using same frequency with this
wireless connection such as a medical equipment,
a microwave or a wireless LAN device.

1-5
HIDDEN KEY MODE
HIDDEN MODE KEYS
EEPROM EDIT Main set ‘-’ (Volume) + Remote control ‘OPTICAL’
EEPROM CLEAR (Initialize) Main set ‘-’ (Volume) + Remote control ‘SOUND EFFECT’
VERSION CHECK Main set ‘-’ (Volume) + Remote control ‘Play’
CLIP OFF
Main set ‘-’ (Volume) + Remote control ‘FUNC’ (Function)CLIP ON
CLIP ON GAIN MONITERING
MAX VOLUME EDIT
ENTRANCE KEY : Main set ‘-’ (Volume) + Remote control ‘SLEEP’
SETTING KEY : VOL +/-
EXIT KEY : Play/Pause
CLIP ALGORITHM EDIT Main set ‘-’ (Volume) + Remote control ‘VOL -’
WIRELESS RF CHANNEL CHANGE Main set ‘-’ (Volume) + Remote control ‘INFO’
SOUND BYPASS Main set ‘-’ (Volume) + Remote control ‘DRC’
APD TIME DISPLAY Main set ‘-’ (Volume) + Remote control ‘AV SYNC’
UP REPEAT (Up)
DOWN Stop/Ok (Down)
RIGHT F.Skip (Right)
LEFT B.Skip (Left)
ENTER Play/Pause (Enter)
DEMO MODE Main set “VOL MIN” (volume minimum state) + Main set ‘F’ (Function)
for 7 seconds.
WIRELESS FACTORY Main set “VOL MIN” (volume minimum state) + Remote control ‘Mute’
for 5 seconds.

1-6
1. Version & Option Check
1) Power on.
2) Press main set "-" (volume -) key and remote control " " (Play/Pause) key during 3 seconds.
3) Check MCS version.
Ex)
4) Press remote control (" ") key 1 time.
Check Wireless Tx version.
Ex)
5) Press remote control (" ") key 1 time.
Check Wireless Rx version.
It’s possible to connect wireless subwoofer.
Ex)
6) Press remote control (" ") key 1 time.
Check EQ version.
Ex)
7) Press remote control (" ") key 1 time.
Check option.
Press remote control " "/ " "/ " " key.
Previous / Next option.
Ex)
8) Power cord unplug.
2. EEPROM Initialize
1) Power on.
2) Press main set “-” (volume -) key and remote control “SOUND EFFECT” during 3 seconds.
3) Display VFD “E2P CLR”.
4) Power off automatically.
5) Power cord unplug.
MCS / EQ HIDDEN KEY GUIDE
P1411182
TX150303
RX000000
Q1411170
OP00-00

1-7
1. Preparation
- Remote control.
- Do format USB Memory to FAT32 File system.
- USB : Update file exist only in the USB Memory stick.
Ex ) LAS550H :
MCS E:\PG540_FW_LAS550H_Ver.bin (if USB driver is E:\)
EQ E:\EQ_PRG.BIN (if USB driver is E:\)
Wireless Tx E:\WIRELESS_TX_150011.bin (if USB driver is E:\)
Wireless Rx E:\WIRELESS_RX_150303.bin (if USB driver is E:\)
2. Update
1) Power on.
2) Change the USB function.
3) Insert USB.
4) Display in VFD.
MCS : “MCS UP” “FINISH” Power off.
EQ : “EQ UP” “FINISH” Power off.
Wireless Tx : “UPDATE” “WR XX”(Progress) “FINISH” Power off.
Wireless Rx : “UPDATE” “SEND XX”(Progress) “FINISH” Power off.
5) Loading is shown while updating.
Never remove USB or AC cord.
6) After update finish, show FINISH in VFD and power of automatically.
7) Power cord un-plug.
MCS / EQ PROGRAM UPDATE GUIDE


1-8
SPECIFICATIONS
• GENERAL
Power requirements Refer to the main label on the unit.
Power consumption Refer to the main label on the unit.
Networked standby : 2.3 W (If all network ports are activated.)
Dimensions (W x H x D) 890 mm x 55 mm x 89 mm
Net Weight (Approx.) 2.72 kg
Operating temperature 5 °C to 35 °C
Operating humidity 5 % to 90 %
• INPUT/OUTPUT
OPT. IN 3 V (p-p), Optical jack x 1
PORT. IN 0.5 Vrms (3.5 mm stereo jack) x 1
HDMI IN 19 Pin (Type A, HDMI™ connector) x 1
HDMI OUT 19 Pin (Type A, HDMI™ connector) x 1
Available Digital Input Audio
Sampling Frequency 32 kHz, 44.1 kHz, 48 kHz, 96 kHz
• USB
Version 2.0
Bus Power Supply 5 V 500 mA
• AMPLIFIER
Total 220 W
Front Middle/ Tweeter 40 W x 2 (4 Ωat 1 kHz) / 20 W x 2 (8 Ωat 12 kHz)
Subwoofer 100 W (6 Ωat 80 Hz)
THD 10 %
• WIRELESS SUBWOOFER
Power requirements Refer to the main label on the unit.
Power consumption Refer to the main label on the unit.
Type 1 Way 1 Speaker
Impedance 6Ω
Rated Input Power 100 W
Max. Input Power 200 W
Dimensions (W x H x D) 171 mm x 350 mm x 261mm
Net Weight (Approx.) 3.9 kg
• BLUETOOTH
Codec SBC
•Designs and specifications are subject to change without prior notice.

2-1
SECTION 2
CABINET & MAIN CHASSIS
CONTENTS
EXPLODED VIEWS ........................................................................................................................................... 2-3
1. MAIN SET SECTION ................................................................................................................................ 2-3
2. WIRELESS SUBWOOFER SECTION...................................................................................................... 2-5
3. PACKING ACCESSORY SECTION ......................................................................................................... 2-7

2-2

C
D
E
AB
G
F
C
D
E
B
A
F
465
272
273
259
259
260
271
A44A
506
506
251
251
464
270
A47
A46
A54
A42
A43
253
464
464
A52
262
A48
CABLE2
CABLE3
FRONT
HDMI &
JACK
WIRELESS
B/T
KEY
MAIN
SMPS
SPK704
263L
257
258
826
464
464
464
464
464
257
464
464
SPK703
464
A55
464
464
258
259
260
259
254
254
256
252
255
464
464
263R
261L
261R
A44B
274
276
275
G
300
EXPLODED VIEWS
1. MAIN SET SECTION
NOTES) THE EXCLAMATION POINT WITHIN AN
EQUILATERAL TRIANGLE IS INTENDED
TO ALERT THE SERVICE PERSONNEL
TO THE PRESENCE OF IMPORTANT
SAFETY INFORMATION IN SERVICE
LITERATURE.

A
300W
954
955
D
E
WIRELESS
SMPS
AMP
B
A
E
D
B
C
C
A900
950
951
956
956
956
A900W
A45W
A54W
A47W
952
CN901
953
A49W
2. WIRELESS SUBWOOFER SECTION
NOTES) THE EXCLAMATION POINT WITHIN AN
EQUILATERAL TRIANGLE IS INTENDED
TO ALERT THE SERVICE PERSONNEL
TO THE PRESENCE OF IMPORTANT
SAFETY INFORMATION IN SERVICE
LITERATURE.

802 Box
803 Packing
820A USB gender
801 Owner’s manual
826 Filter, Ferrite Core
900 Remote control
804 Bag
829 Cable tie
837 Cover foot (2)
808 Batteries (2)
835 Wall bracket 836 Screws (2)
823 HDMI cable
806 Optical cable
OPTIONAL PART


3. PACKING ACCESSORY SECTION

2-8

3-1
SECTION 3
ELECTRICAL
CONTENTS
ONE POINT REPAIR GUIDE ............................................................................................................................ 3-2
1. NO POWER PROBLEM (PVDD) ............................................................................................................ 3-2
2. POWER ON ERROR .............................................................................................................................. 3-3
3. NO SOUND (PORTABLE FUNCTION) .................................................................................................. 3-4
4. NO WIRELESS ....................................................................................................................................... 3-5
5. NO BLUETOOTH.................................................................................................................................... 3-6
6. NO SOUND (USB).................................................................................................................................. 3-7
7. NO SOUND (OPTICAL).......................................................................................................................... 3-8
8. HDMI PROBLEM .................................................................................................................................... 3-9
WAVEFORMS OF MAJOR CHECK POINT.................................................................................................... 3-10
1. CRYSTAL.............................................................................................................................................. 3-10
2. FLASH MEMORY ................................................................................................................................. 3-11
3. TACT KEY............................................................................................................................................. 3-12
4. USB....................................................................................................................................................... 3-13
5. REMOTE CONTROL ............................................................................................................................ 3-14
6. OPTICAL............................................................................................................................................... 3-15
7. PORTABLE ........................................................................................................................................... 3-16
8. AUDIO PWM ......................................................................................................................................... 3-17
9. AUDIO AMP .......................................................................................................................................... 3-19
WIRING DIAGRAM.......................................................................................................................................... 3-21
BLOCK DIAGRAM .......................................................................................................................................... 3-23
CIRCUIT DIAGRAMS ...................................................................................................................................... 3-25
1. SMPS CIRCUIT DIAGRAM .................................................................................................................. 3-25
2. MAIN - DSP CIRCUIT DIAGRAM......................................................................................................... 3-27
3. MAIN - PWM & AMP CIRCUIT DIAGRAM ........................................................................................... 3-29
4. MAIN - POWER CIRCUIT DIAGRAM................................................................................................... 3-31
5. HDMI & JACK CIRCUIT DIAGRAM...................................................................................................... 3-33
6. FRONT CIRCUIT DIAGRAM ................................................................................................................ 3-35
7. TACT KEY CIRCUIT DIAGRAM ........................................................................................................... 3-37
CIRCUIT VOLTAGE CHART........................................................................................................................... 3-39
PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 3-41
1. SMPS P. C. BOARD DIAGRAM ........................................................................................................... 3-41
2. MAIN P. C. BOARD DIAGRAM ............................................................................................................ 3-43
3. HDMI & JACK P. C. BOARD DIAGRAM .............................................................................................. 3-45
4. FRONT P. C. BOARD DIAGRAM......................................................................................................... 3-45
5. TACT KEY P. C. BOARD DIAGRAM.................................................................................................... 3-45

3-2
ONE POINT REPAIR GUIDE
1. NO POWER PROBLEM (PVDD)
No power problem occurs when you power on the unit
1-1. Solution
Replace SMPS board.
1-2. How to troubleshoot (Countermeasure)
1) Check the PVDD voltage 18.7 V at pin1, 2, 3.
When you check the no power at this point, then replace SMPS board.
1-3. Service hint (Any picture / Remark)
< MAIN board top view >
PVDD
PVDD

3-3
ONE POINT REPAIR GUIDE
2. POWER ON ERROR
No display or Not working.
2-1. IC601
1) Check 3.3 VA at L602.
2) If 3.3 VA is not checked at the point, then find 18.7 V at pin7 of IC601.
3) 1), 2) is NG. Replace IC601.
2-2. IC602
1) Check 5.1 VA at L606.
2) If 5.1 VA is not checked at the point, then find 18.7 V at pin7 of IC602.
3) 1), 2) is NG. Replace IC602.
2-3. IC603
1) Check 12 VA at L604.
2) If 12 VA is not checked at the point, then find 18.7 V at pin7 of IC603.
3) 1), 2) is NG. Replace IC603.
< MAIN board top view >
< MAIN board top view >
< MAIN board top view >
L602
L602
L606
L606
L604
L604
IC601 pin7
IC601 pin7
IC602 pin7
IC602 pin7
IC603 pin7
IC603 pin7

3-4
ONE POINT REPAIR GUIDE
3. NO SOUND (PORTABLE FUNCTION)
3-1. Solution
Replace IC508 or portable jack (JK851).
3-2. How to troubleshoot (Countermeasure)
1) Please check the soldering status of JK851.
2) Please check L854, L855 (PORT_L, PORT_R signal) of portable jack (JK851).
If you cannot find input signal, replace JK851.
3) If you can find input signal, check pin13,14 of IC508.
4) If you can’t find signal at pin13,14 of IC508, replace IC508.
3-3. Service hint (Any picture / Remark)
< HDMI & JACK board top view >
< MAIN board bottom view >
JK851
JK851
L854
L854
L855
L855
IC508
IC508

3-5
ONE POINT REPAIR GUIDE
4. NO WIRELESS
4-1. Solution
Replace IC505 on MAIN board.(No 3.3 V)
4-2. How to troubleshoot (Countermeasure)
1) Please check externally status of Wireless board to board connection on your eyes.
(at CN506 and Wireless module)
2) Please check 3.3 V of WL_3V3 (at L509).
If 3.3 V is ok at L509, please check SPI signal (WL_SPI_CS/D0/WP/DI/CLK) of IC505 (pin1, 2, 3, 5, 6).
3) If you can’t have no signal, please replace IC505.
4) If 3) is OK, then proceed S/W update.
Update Wireless TX (Main set) and Wireless RX (Subwoofer) each.
4-3. Service hint (Any picture / Remark)
< MAIN board bottom view >
IC505
IC505
L509
L509
CN506
CN506