DiBoss LT-32HTFH User manual

SERVICE MANUAL
COLOR TFT-LCD TV
SERVICE MANUAL
MODEL :LT-32HTFH
CAUTION !!
BEFORESERVICINGTHETFT-LCDTV,
READTHE SAFETY PRECAUTIONS IN THIS MANUAL.

SERVICE MANUAL
CONTENTS
Contents ------------------------------------------------------------------------- 2
Safety precautions ----------------------------------------------------------- 3
Servicing precautions ------------------------------------------------------- 4
Specifications ------------------------------------------------------------------ 5
Location of control ----------------------------------------------------------- 9
Trouble Shooting ------------------------------------------------------------- 12
Deassembly procedure ---------------------------------------------------- 14
Exploded Drawing ----------------------------------------------------------- 19
Wire dressing ------------------------------------------------------------------ 20
Adjustment instruction with Default FactoryData----------------- 21
Inspection instruction ------------------------------------------------------ 23
PCB Layout --------------------------------------------------------------------- 26
Schematic Diagram -----------------------------------------------------------31
Replacement part list -------------------------------------------------------- 32
Block Diagram ----------------------------------------------------------------- 33
Circuit descriptions ---------------------------------------------------------- 34

SERVICE MANUAL
SAFETY PRECAUTIONS
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth
ground (Water Pipe, Conduit, etc.) and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more
sensitivity.
Reverse plug of the AC cord into the AC outlet and repeat AC voltage measurements for each
exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS, which is,
corresponds to 0.5mA.
In case any measurement is out of the limits specified, there is possibility of shock hazard and
the set must be checked and repaired before it is returned to the customer.
Leakage Current Hot Check circuit
!! Important Safety Notice !!
Many electrical and mechanical parts in this chassis have special safety-related
characteristics.
These parts are identified by in the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components
as recommended in this manual to prevent Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.

SERVICE MANUAL
SERVICING PRECAUTIONS
CAUTION!!
Before servicing receivers covered by this service manual, read and follow the SAFETY
PRECAUTIONS on page 2 of this publication.
General Servicing Precautions
1.Always unplug the receiver AC power cord from AC power source before;
ⓐRemoving or reinstalling any component, circuit board module or any other receiver assembly.
ⓑDisconnecting or reconnecting any receiver electrical plug or other electrical connection.
ⓒConnecting a test substitute in parallel with an electrolytic capacitor in the receiver.
CAUTION!! A wrong part substitution or incorrect polarity installation of electrolytic capacitors
may result in an explosion harzard.
2.Do not spray chemicals on or near this receiver or any of its assemblies.
3.Do not defect any plug/socket voltage interlocks with which receivers covered by this service
manual might be equipped.
4.Always connect the test receiver ground lead to the receiver chassis ground before
connecting the test receiver positive lead. Always remove the test receiver ground lead last.
5.Do not connect the test fixture ground strap to power supply heatsink in this receiver
Electrostatically Sensitive(ES) Devices
Some semiconductor(solid state) devices can be damaged easily by static electricity. Such
components commonly are called Electrostatically Sensitive(ES) Device.Examples
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit board will weaken the adhesive
that bonds the foil to the circuit board causing the foil th separate from or “lift-off” the board.
The following guidelines and procedures should be flollowed whenever this condition is
encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the following procedure to install a
jumper wire on the copper pattern side of the circuit board.(Use this technique only on IC
connections.)
1.Carefully remove the damaged copper pattern with a sharp knife.
(Remove only as much copper as absolutely necessary.)
2.Carefully scratch away the solder resist and acrylic coating(if used) from the end of the
remaining coopper pattern.
3.Bend a small “U” in one end of a small guage jumper wire and carefully crimp it around the
IC pin.
4.Route the jumper wire along the path of the out-away copper pattern and let it overlap the
previously scraped end of the good copper pattern. Solder the overlapped area and clip off
any excess jumper wire.

SERVICE MANUAL
SPECIFICATIONS
Note: Specifications and others are subject to change without notice for improvement.
1.Scope.
This document is the specification of 32” TFT-LCD Color TV.
2.Power
1) Power requirement
150W
2) AC / DC SMPS.
Input Frequency : 50 / 60㎐
Input Voltage: AC 100V- 240V 2.5A ~1.5A
Output Voltage: DC 12V, 24V
3) Power cord
Use UL listed and CSA certified detachable power cord type; SVT, 3-conductors, 18AWG
For AC 120V area. Use VDE listed detachable power cord type; HO5VV-F, 3-conductors,
18AWG for AC 220 240V area.～
3.Tuning system
FVS 100 Program
4.Sound output
10W+10Wrms Stereo (Max)
5.Antenna input impedance
VHF / UHF at 75ohm
6.OSD Type (On Screen Display)
Windows type (Center)
7.External in/output
HDMI INPUT, PC ANALOG INPUT, PC AUDIO INPUT, HEADPHONE OUTPUT, SVC port
S-VIDEO AUDIO INPUT, S-VIDEO INPUT, COMPONEN INPUT, COAXIAL OUT,
SCART 1(FULL), SCART 2(HALF), TUNER
8. Function
CATV/Hyper band
Auto Program
Manual Program
Auto Sleep
Quick view
ACMS(Auto channel Memory System)
PSM(Picture Status memory)
SSM(Sound Status memory)
PIP :COMPONET, PC-ANALOG, HDMI(Main) – Tuner, SCART 1, SCART 2, S-Video(Sub)
TUNER, SCART1, SCART2, S-Video(Main) – PC ANALOG, HDMI, COMPONET(Sub)
ARC(ASPECT RATIO CONTROL)

SERVICE MANUAL
SPECIFICATIONS
9.Receiving RF TV system
NO
Model System
LT-32HTFH //
1 PAL-B ○/ /
2 PAL-G ○/ /
3 PAL-I, I /I ○/ /
4 PAL-D ○/ /
5 PAL-K ○/ /
6 SECAM-B ○/ /
7 SECAM-G ○/ /
8 SECAM-D ○/ /
9 SECAM-K ○/ /
10 SECAM-K1 ○/ /
11 SECAM-I (6.0) ○/ /
12 NTSC-3.58 / 4.5 X//
13 NTSC-3.58 / 5.5 X//
14 NTSC-3.58 / 6.0 X//
15 NTSC-3.58 / 6.5 X//
16 NTSC-3.58 / 4.5(5.0) X//
17 NTSC-4.43 / 5.5 X//
18 NTSC-4.43 / 6.0 X//
19 NTSC-4.43 / 6.5 X//
20 PAL 5.5 / 60Hz ○/ /
21 PAL 6.0 / 60Hz ○/ /
22 PAL 6.5 / 60Hz ○/ /
23 SECAM 5.5 / 60Hz ○/ /
24 SECAM 6.0 / 60Hz ○/ /
25 SECAM 6.5 / 60Hz ○/ /
26 SECAM L / L' ○/ /
TOTAL SYSTEM 18 //

SERVICE MANUAL
10. PC Mode Scan Frequency & Timing
1) Scan Freq: H: 31～56 kHz / V: 56～75㎐
2) Preset Timing Chart
Note!! :
If the set is cold, there may be a small “flicker” when the set is switched on. This isⓐ
Normal, there is nothing wrong with the set.
If possible, use the XGA 1024 x 768@60HZ video modeⓑto obtain the best image quality
for your LCD monitor. If used under the other resolutions, some scaled or processed
pictures may appear on the screen.
Some dot defects may appear on the screen, like Red, Green or Blue spot. However, thisⓒ
will have no impact or effect on the monitor performance.
SPECIFICATIONS

SERVICE MANUAL
11. TFT – LCD Panel Character
Description
LTA320W2-L03 is a color active matrix TFT(Thin Film Transistor) liquid crystal display(LCD)
that uses amorphous silicon TFTs as a switching devices. This model is composed of a
TFT LCD panel, a driver circuit and a back-light system. The resolution of a 32.0" contains
1366 X 768 pixels and can display up to 16.7 million colors with wide viewing anale of
85˚or higher in all directions.
Features
- High contrast ratio, high aperture structure
- APVA(Advanced Patterned Vertical Align) mode
- Wide verwing anale(±170°)
- High speed response
- WXGA(1366 X 768 pixels) resolution(16:9)
- Low Power consumption
- Dyrect Type 16 CCFL(Cold Cathode Fluorescent Lamp)
- DE only mode
- LVDS(Low-Voltage Differential Signal) interface.(1pixel/clock)
Applications
- Home-alone Multimedia TFT-LCD TV
- Display terminals for AV applications products
- High Definition TV(HD TV)
●Feature
Size 32.0 inches
Driver element a-si TFT Active Matrix
Display area 697.6845mm(H) X 392.256mm(V)
Display colors 16.7M(true)
Number of Pixels 1366 X 768 Pixel(16:9)
Pixel arrangement RGB Vertical Stripe
Pixel Pitch 0.51075mm (H) x 0.51075mm(W)
Display mode Normally Black
Surface treatment Haze 44%, Hard-Coating(3H)
SPECIFICATIONS

All the functions can be controlled with the remote controller. Some functions can
also be adjusted with the buttons on the side panel of the set.
Remote controller
Before you use the remote controller, please install the batteries.
1. POWER
Turns the TV on from standby or off to standby mode.
2. MUTE
Turns the sound on and off.
3. NUMBER buttons
Selects programme numbers.
4. TV/AV
Selects TV, VIDEO, S-VIDEO,
RADIO(Only when the set is Radio On.),
COMPONENT1/2, PC ANALOG, HDMI mode.
Clears the menu from the screen.
5. MENU
Displays a main menu.
6. LIST
Displays the programme list menu.
7. I/II
Selects the language during dual language broadcast.
Selects the sound output.
8. SLEEP
Sets the sleep timer.
9. PÏP
Returns to the previously viewed programme.
10. PRx/PRy(Programme Up/Down)
Selects next programme or a menu item.
11. OK
Accepts your selection or displays the current mode.
12. VOLÏ/VOLq(Volume Up/Down)
Adjusts the sound level.
13. TV/PC
Selects TV or PC mode directly.
LOCATION OF CONTROL
SERVICE MANUAL
LOCATION OF CONTROL

14. PICTURE( )
Recalls your preferred picture setting
15. SOUND( )
Recalls your preferred sound setting
16. ARC( )
You can watch TV in various picture formats; Auto,
16:9, 14:9, 4:3, 16:9 Zoom, 14:9 Zoom, 4:3 Zoom.
Repeatedly press the ARC button to select your
desired picture format.
Note. 16:9 and 4:3 in PC mode are available.
17. TELETEXT buttons
These buttons are used for Teletext.
For further details, see the ‘Teletext’ section.
18. INPUT( )
Selects the AV source of sub picture in PIP mode.
19. PIP( )
Displays a PIP(Picture In Picture) screen.
20. POSITION( )
Selects a position of PIP screen.
21. SWAP( )
Switches a main picture to sub picture in PIP mode.
22. MODE( )
Selects a PIP screen mode. – 16:1, 9:1 and 3:1 mode.
23. PIP PRx/PIP PRy
Selects a programme when RF signal is displayed in
PIP mode.
24. Ïq
Adjusts menu settings.
LOCATION OF CONTROL
SERVICE MANUAL
LOCATION OF CONTROL

SERVICE MANUAL
LOCATION OF CONTROL
1-3. Controller of Panel
< SIDE VIEW>
1.ON/OFF:
Switches TV set on or off.
2.MENU:
Display a menu.
3.+ PR -( Programme Up/Down):
Selects a programme or a menu item.
4.+ VOL -( Volume Up/Down):
Adjusts the volume.
Adjusts menu settings.
5.TV/AV:
Selects input signal source.
Clears the menu from the screen.
6:POWER INDICATOR:
Illuminates red when the TV is in-
power standby mode.
Illuminates green when the TV is-
switched power on mode.
Illuminates amber when the TV is-
switched power saving mode.
7.REMOTE CONTROL SENSOR:
Accepts the IR signal of remote
controller.
6 7
1
2
3
4
5

SERVICE MANUAL
TROUBLE SHOOTING
Check
P803 (8~12) : 24V?
P804 (6~10) : 24V
Replace LCD Panel.
(If
p
ossible, re
p
lace
inverter module.)
Y
Check
Q804 (3) : 24V?
N
Check
P303 (25~27) : 5V? Y
Check
Q804 (3) : 24V?
Q804 (1)
:
0V?
N
Replace
SMPS
Replace
Q800
Replace
Q804
Check
IC805 (3) : 5V?
IC805 (4)
:
0V?
Replace
IC805
Y
Y
N
N
Y
N
Check
IC821 (3) : 5V?
IC821 (4)
:
0V?
Replace
IC821
Y
N
Replace
IC804
No Raster

SERVICE MANUAL
TROUBLE SHOOTING
IC601 (4,7,12,15)
= 24V? Y
Check
24V Line
N
IC601 (25-Mute)
<0.7V?
(L:Mute/ H:On)
YZD601 (C)
< 1V?
Replace
ZD601
N
IC101
(123/124 L/R)
Q104/105 (E)
Sound Wave ?
N
Replace IC101
N
Y IC202 (10)
= 0V?
Replace
IC202
N
No LED LED blinking
Resistance : 0 ?
IC804 (4) <->
GND
Y
Replace
IC804 / D850
Y
Check
All SCL/SDA
TTL Level ?
Y
IC01 (69~75)
Scaler
Communic
ation Lines)
TTL Level ?
Y
Replace
Non-Operation
IC.
N
Replace IC01
N
No Sound &
Picture OK
No Operation

SERVICE MANUAL
DEASSEMBLY PROCEDURE
1. Disassembly procedure
1).Back cover
Remove 4 screws
Remove 16crews
Removal of Backcover

SERVICE MANUAL
DEASSEMBLY PROCEDURE
2).Metal plate & Rear chassis
Remove 5 screws
Removal of rear metal chassis...
Remove 2 screws
Slide away the metal plate

SERVICE MANUAL
DEASSEMBLY PROCEDURE
3).Metal plate & Rear chassis
Remove Main PCB 10 screws
Removal of Main PCB
Remove 6 connector

SERVICE MANUAL
DEASSEMBLY PROCEDURE
4).LCD Panel chassis
Remove 22 screws, then take LCD-BRKT
Removal of LCD Module take LCD-BRKT
Removal of LCD Module

SERVICE MANUAL
DEASSEMBLY PROCEDURE
5).LCD Module
Remove 8 screws, then take LCD-BRKT
Front mask remains after removing LCD Module

NO PART NO DESCRIP TION MATERKAL COLOR FINISH Q'TY
1 - DECO FRONT PMMA BLACK 1
2 610-006A SPEAKER 10W
,
10Ω
-2
3
400-021C FRONT COVERPC+ABSSILVER,BLACK1
4 408-002D LENS SENSOR PC TRANSPARENCE 1
5IRPCB--1
6CONTROLPCB--1
7404-004B BLOCKKNOBABSSILIVER1
8 450-001Z CONTROL PLATE AL SILIVER 1
9PANV320W2L01 PANELSAMSUNG -1
10407-005F BRKTL,REGI-2
11407-001Z LCD BRKTEGI-1
12620-005D SMPS --1
13AYMALT52A01A MAINPCBASS'Y--1
14407-007S,TJACK SHIELD SPTH-1
15407-002L REARSHIELD EGI-1
16 407-003F BACKCOVERPC+ABSDARK GRAY1
17401-0032 BOTTOMBRKTEGI-1
18450-001Y DECO STAND PMMABLACK 1
19 450-004F,G,HREAR PLATEPVC BLACK1
20402-004WSTANDBOTTOMABS SILVER 1
21402-004C STAND FRONT ABSDARK GRAY1
22401-0016 STAND BRKTEGI-1
23402-004D STAND REARABSDARK GRAY1
24410-001Q BTB4*12 39
25410-001K TTB3*88
26410-001L TTB3*10 5
27410-003R PBTB4*10 4
28410-002R PP4*12 4
29 410-001R PB4*813
30410-001N FTB3*618
AYCOLT40A01A
SCREW MACHINE
SCREW TAPPING
SZN
12
3
4 5
6
7
8
10
11
12
14
15
13
16
17
18 19
20 21 22 23
24
25
25
25
25
25
26
26
27
27
28
29
31
31
31
31 31
31
32
MATERIAL DATA
2005. 04. 18
THIS ENGR
D.H.KIM
TREATMENT GHK
MODEL APPD SCALE SHEET
LT32H - 1 / 1
SET Exploded Drawing
MA05-005
DRAWINGNO.
TITLE
9
MECHANICAL EXPLODED VIEW

SERVICE MANUAL
WIRE DRESSING
1. Wire Dressing
Note: Using acetate
Using Copper (Conducted tape)
Using Ferrite Cpre
Using Copper Tape
Using
Conducted tape
Using
F
errite
C
pre