Samsung HW-T450 User manual

Wireless Audio - Party Box Contents
SERVICE
Manual
HW-T450
Sound bar
1. Precautions
2. Product Specifications
3. Disassembly and Reassemble
4. Troubleshooting
5. PCB Diagram
6. Schematic Diagram
Model
HW-T450
7.
Exploded View & Part List

Contents
1. Precautions
1-1. Safety Precautions.........................................................................................................................1-1
1-2. Servicing Precautions ....................................................................................................................1-3
1-3. Precautions for Electrostatically Sensitive Devices (ESDs)...........................................................1-4
1-4. Installation Precautions..................................................................................................................1-5
2. Product Specifications
2-1. Product Feature .............................................................................................................................2-1
2-2. Specifications.................................................................................................................................2-2
2-3. Specification Comparison to Old Models .......................................................................................2-3
2-4. Accessories....................................................................................................................................2-4
3. Disassembly and Reassemble
3-1. Product Disassembly .....................................................................................................................3-1
4. Troubleshooting
4-1. Checkpoints by Error Mode ...........................................................................................................4-1
4-1-1. No Power ...........................................................................................................................4-2
4-1-2. No Sound Output ...............................................................................................................4-3
4-2. Measures to be taken when the Protection Circuit operates .........................................................4-8
4-2-1. AMP Pre-Inspection relating to Power Protection..............................................................4-9
4-3. Initialization & Update....................................................................................................................4-10
4-3-1. Initialization method ...........................................................................................................4-11
4-3-2. How to check the Firmware version...................................................................................4-12
4-3-3. USB Update procedure......................................................................................................4-13
5. PCB Diagram
5-1. Wiring Diagram ..............................................................................................................................5-1
5-2. MAIN PCB Top...............................................................................................................................5-2
5-3. MAIN PCB Bottom .........................................................................................................................5-3
5-3-1. Pin Connection...................................................................................................................5-4
5-3-2. Test Point Wave Form........................................................................................................5-6
5-4. Power PCB Top.............................................................................................................................5-7
5-5. Power PCB Bottom........................................................................................................................5-8
5-6. Lamp+Key PCB Top......................................................................................................................5-9
5-7. Lamp+Key PCB Bottom.............................................................................................................5-10
4-1-3. RC do not work ...............................................................................................................4-4
4-1-4. No Output by optical in ......................................................................................................4-5
4-1-5. No Output by Aux in .........................................................................................................4-6
4-1-6. No Output by Bluetooth ...................................................................................................4-7

6. Schematic Diagram
6-1. Overall Block Diagram ...................................................................................................................6-1
6-2. MAIN-1...........................................................................................................................................6-2
6-3. MAIN-2...........................................................................................................................................6-3
6-4. MAIN-3...........................................................................................................................................6-4
6-5. MAIN-4 ........................................................................................................................................6-5
6-6. MAIN-5...........................................................................................................................................6-6
6-7. MAIN-6...........................................................................................................................................6-7
6-8. Power-1..........................................................................................................................................6-8
6-9. LED-1.............................................................................................................................................6-9
6-10. Key-1...........................................................................................................................................6-10
7. Exploded View & Part List
7-1. Exploded View & Part List ............................................................................................................7-1

1-1
1. Precautions
• Follow these safety instructions while servicing the ESD to prevent damage and to protect against potential hazards such as
electrical shock and X-rays.
Warning
• For continued safety, do not attempt to modify the circuit board.
• Disconnect the AC power and DC power jack before servicing.
1-1. Safety Precautions
1. When reinstalling the chassis and its assemblies, be sure to restore all of the protective devices, including the control
knobs and the compartment covers.
2. Make sure that there are no cabinet openings through which people (particularly children) can make contact with
dangerous internal components.
3. Design Alteration Warning:
Never alter or add to the mechanical or electrical design of the unit.
Example: Do not add auxiliary audio or video connectors. Such alterations might create a safety hazard.
Also, any design changes or additions will void the manufacturer’s warranty.
4. Leakage Current Hot Check. Fig. 1-1 AC Leakage Test
Warning
• Do not use an isolation transformer during
this test.
• Use a leakage current tester or a metering
system that complies with American
National Standards Institute (ANSI C101.1,
Leakage Current for Appliances), and
Underwriters Laboratories (UL Publication
UL1410, 59.7).
With the unit completely reassembled, plug the AC cord directly
into a 120V AC outlet. With the unit’s power switched
from the ON to the OFF position, measure the current between
a known ground and all exposed metal parts.
Known Grounds - Earth
Known Metal parts - screwheads, metal cabinets, etc.
<Fig. 1-1 AC Leakage Test>
DEVICE
UNDER
TEST
(READING SHOULD)
NOT BE ABOVE 0.5mA
LEAKAGE
CURRENT
TESTER
TEST ALL
EXPOSED METAL
SURFACES
2-WIRE CORD
ALSO TEST WITH
PLUG REVERSED
(USING AC ADAPTER
PLUG AS REQUIRED)
EARTH
GROUND

1-2
5. Insulation Resistance Cold Check:
(1) With the unit’s AC plug disconnected from the AC source,
connect an electrical jumper across the two AC prongs.
(2) Set the power switch to ON.
(3) Measure the resistance between the shorted AC plug and
any exposed metallic parts.
Example: screwheads, metal cabinets, antenna port.
chassis, the measured resistance should be between
1 and 5.2 megohms. If there is no return path, the
measured resistance should be “infinite.”
If the resistance is outside these limits, a shock hazard might exist.
See Fig. 1-2 Insulation Resistance Test
6. Components, parts and wiring that appear to have overheated or that are otherwise damaged should be replaced with
parts that meet the original specifications. Always determine the cause of damage or overheating, and correct any potential
hazards
7. Observe the original lead dress, especially near the following areas:
Antenna wiring, sharp edges, and especially the AC and high voltage power supplies. Always inspect for pinched,
out-of-place, or frayed wiring. Do not change the spacing between components and the printed circuit board.
Check the AC power cord for damage. Make sure that no wires or components touch thermally hot parts.
8. Product Safety Notice:
Some electrical and mechanical parts have special safety-related characteristics which might not be obvious from visual
inspection. These safety features and the protection they give might be lost if the replacement component differs from the
original-even if the replacement is rated for higher voltage, wattage, etc.
9. Components that are critical for safety are indicated in the circuit diagram by shading, or .
Use replacement components that have the same ratings, especially for flame resistance and dielectric strength
specifications. Areplacement part that does not have the same safety characteristics as the original might create shock, fire
or other hazards.
Antenna
Terminal
ohm
<Fig. 1-2 Insulation Resistance Test>
Exposed
Metal Part
Ohmmeter

1-3
1-2. Servicing Precautions
Warning
• An electrolytic capacitor installed with the wrong polarity might explode.
Caution
• Before servicing units covered by this service manual, read and follow the Safety Precautions section of
this manual.
Note
• If unforeseen circumstances create conflict between the following servicing precautions and any of the
safety precautions, always follow the safety precautions.
1. Servicing precautions are printed on the cabinet. Follow them.
2. Always unplug the unit’s AC power cord from the AC power source before attempting to: (a) Remove or reinstall any
component or assembly, (b) Disconnect an electrical plug or connector, (c) Connect a test component in parallel with an
electrolytic capacitor.
3. Some components are raised above the printed circuit board for safety. An insulation tube or tape is sometimes used. The
internal wiring may be clamped to prevent contact with thermally hot components. Reinstall all such elements to their original
position.
4. After servicing, always check that the screws, components and wiring have been correctly reinstalled.
Make sure that the portion around the serviced part has not been damaged.
5. Check the insulation between the blades of the AC plug and accessible conductive parts (examples: metal panels, input
terminals and earphone jacks).
6. Insulation Checking Procedure: Disconnect the power cord from the AC source. Connect an insulation resistance meter
(500V) to the blades of the AC plug.
7. The insulation resistance between each blade of the AC plug and accessible conductive parts (see above) should be greater
than 1 megohm.
8. Never defeat any of the B+ voltage interlocks. Do not apply AC power to the unit (or any of its assemblies) unless all solid-
state heat sinks are correctly installed.
9. Always connect a test instrument’s ground lead to the instrument chassis ground before connecting the positive lead; always
remove the instrument’s ground lead last.
Warning
• First read the “Safety Precautions” section of this manual. If some unforeseen circumstance creates a
conflict between the servicing and safety precautions, always follow the safety precautions.

1-4
1-3. Precautions for Electrostatically Sensitive Devices (ESDs)
• Some semiconductor (“solid state”) devices are easily damaged by static electricity.
Such components are called Electrostatically Sensitive Devices (ESDs). Examples include integrated circuits and some
field-effect transistors. The following techniques will reduce the occurrence of component damage caused by static
electricity.
1. Immediately before handling any semiconductor components or assemblies, drain the electrostatic charge from your
body by touching a known earth ground. Alternatively, wear a discharging wrist-strap device. (Be sure to remove it prior to
applying power-this is an electric shock precaution.)
2. After removing an ESD-equipped assembly, place it on a conductive surface such as aluminum foil to prevent accumulation
of electrostatic charge.
3. Do not use freon-propelled chemicals. These can generate electrical charges that damage ESDs.
4. Use only a grounded-tip soldering iron when soldering or unsoldering ESDs.
5. Use only an anti-static solder removal device. Many solder removal devices are not rated as “anti-static” (these can
accumulate sufficient electrical charge to damage ESDs).
6. Do not remove a replacement ESD from its protective package until you are ready to install it.
Most replacement ESDs are packaged with leads that are electrically shorted together by conductive foam, aluminum foil or
other conductive materials.
7. Immediately before removing the protective material from the leads of a replacement ESD, 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 body motions when handling unpackaged replacement ESDs. Motions such as brushing clothes together, or lifting
your foot from a carpeted floor can generate enough static electricity to damage an ESD.

1-5
1-4. Installation Precautions
1. Keep the product away from a heat source such as candle light, mosquito repellent incense, heating equipment, or direct
sunlight. Otherwise, this may cause fire.
2. Do not install the product on a place that is shaking, tilted, unstable, or seriously vibrating. The product may drop to get
damaged or injure a person. If using the product in a highly vibrating place, it may be broken or cause fire.
3. When moving the product, turn off the power switch and unplug all the connected cables with the product such as the
power plug and antenna cable. If the power cord is damaged, this may cause electric shock or fire.
4. Secure room for ventilation. Keep at least 10 cm of distance from the rear wall, and at least 5 cm from either side wall.
5. Installing the product in a special place like below rather than normal environment may cause serious quality concerns
due to its special conditions. If this is the case, make sure to contact a local Samsung service center before installing the
product. (Special places: a place where a large amount of dust is accumulated; where chemical substances are used or the
ambient temperature is too high or low; a place that is full of moisture or water; in transportation vehicles such as a car; or in
public places such as the airport or subway station where the product is supposed to operate uninterruptedly for a long time)
6. Keep the packaging plastic wrapper out of children’s reach. If children play with it improperly, they may get suffocated.
7. If installing the product on a display cabinet, shelf, desk, etc., keep the product from protruding on its lower side. If the
product falls, it may break or cause physical injury. Use only the display cabinet or shelf that fully covers the product.
8. If using lithium batteries, carefully read the following precautions:
Caution
• Ensure the batteries are inserted in the right direction. Otherwise, they may cause an explosion.
Dispose of used batteries according to the manufacturer’s instructions.
•Do not expose the battery to fire.
• Do not disassemble, short - cut, or heat the battery.
• Use only the same type and size of batteries for replacement.
• Do not expose the battery to fire or excessive heat.

Total Power
- 200W RMS (mid 35Wx2+wireless subwoofer 130Wx1)
2.1 channel system(T450)
USB Music Playback, BLUETOOTH
Optical in
Product Specifications
2. Product Specifications
2-1. Product Feature
2-1
Product Feature

2-2
Product Specifications
2-2. Specifications
Basic Specification
NOTES
•Samsung Electronics Co., Ltd reserves the right to change the specifications without notice.
•Weight and dimensions are approximate.
•Dispose unwanted electronics through an approved recycler.
To find the nearest recycling location, go to our website: www.samsung.com/recyclingdirect or call
(877) 278 - 0799

Product Specifications
2-3. Accessories
2-3

AH81-11678A
AH81-11679A
AH81-11680A
Product Specifications
2-4. Accessories
Product Description Parts Code Remark
Power Cord : 2PCS
Samsung Electronics
Service Center
(The part code for
some accessories
may differ depending
on your region.)
Batteries
Remote Control
2-4

ViewExploded Disassembly and Reassembly

2.1. Unfix 2 screws on main board
3.1.Unfix 7 screws and unplug FFC module cable
to disassemble Main board/TX Module/Socket/
VFD PCBA/Metal Plate

3. Disassembly and Reassemble
Warning
• As this product has parts that are sensitive to static electricity, be careful when handling them.
Caution
• Disconnect the product from the power source before disassembly.
• Follow these directions carefully; never use metal instruments to pry apart the cabinet.
• When disassembling the product, do not use any metal tools except for the provided jig.
Disassembly and Reassembly
3. Remove Main board/TX Module/
Socket/VFD PCBA/Metal Plate
2.2. Unplug 2 cables from connector.
2. Remove Main board/TX Module/
VFD PCBA ASSY
Remove rear cover


1.
DescriptionPict
u
redescription
3-1. Product Disassembly
Note: Prepare cushions to be placed on the floor to
protect the machine
4.Remove KEY board
4.1.Unfix 3 screws to disassemble KEY Board

6.1.Unplug VFD Key board cable and disassemble
power board as images show.
6.Remove Power Board
Note
• Reassembly procedures are in the reverse order of disassembly procedures.
• The exterior may differ depending on the product.
5.Remove I/O cover
5.1. Remove right rear L cover and 4 screws to
dissemble I/O cover as images show

4-1
Troubleshooting
4. Troubleshooting
4-1. Checkpoints by Error Mode
Oscilloscope
SettingValues
CheckDCvoltageCheckI2C&I2S
signal
checkPWM
signal
CheckL+,L‐
signal
Voltage/DIVDepend voltage 1V/div10V/div10V/div
TIME/DIV500ms/div20us/div1us/div500us/div

4-2
Troubleshooting
4-1-1. No Power
Symptom
• If you connect the power cables, the LED on the front will turn on
• If the units do not work
Major
checkpoints
Diagnostics
Caution •Before working, disconnect the power cord.
In case of no power

4-5
Troubleshooting
4-1-2. No Audio Output
Symptom • In case of no sound
Major
checkpoints
• Speaker connector is not connected properly or check for damage.
• Make sure your sound processing functions operate properly on the motherboard.
• Make sure the speaker isn’t bad.
Diagnostics
Caution •Before working, disconnect the power cord.

4-5
Troubleshooting
4-1-3. Optical is not working
Symptom • In case of optical is not working
Major
checkpoints
Diagnostics
Caution •Before working, disconnect the power cord.

4-5
Troubleshooting
4-1-4. No sound output(Subwoofer)
Symptom • In case of no sound(subwoofer)
Major
checkpoints
Diagnostics
Caution •Before working, disconnect the power cord.