Samsung LA22N21B Schematic
TFT-LCD TV/MONITOR
Chassis Model
VA22SO LA22N21B
Manual
SERVICE
TFT-LCD TV/MONITOR CONTENTS
1. Precautions
2. Product Specifications
3. Disassembly & Reassembly
4. Alignment & Adjustments
5. Troubleshooting
6. Exploded View & Parts List
7. Parts List
8. Block Diagram
9. Wiring Diagram
10. PCB Layout
11. Schematic Diagrams
12. Panel Description
Samsung Electronics Co.,Ltd.
416, Maetan-3Dong, Yeongtong-Gu, Suwon City, Kyungki-Do,
Korea, 442-742
Printed in Korea
P/N : BN82-00103W-00
http : //www.samsungmonitor.com (SyncMaster Worldwide)
http : //www.samsung-monitor.com (SyncMaster USA)
URL : http://itself.sec.samsung.co.kr/
❈ This Service Manual is a property of
Samsung Electronics Co., Ltd.
Any unauthorized use of Manual can be
punished under applicable International
and/or domestic law.
1 Precautions
LA22N21B 1-1
1-1-1 Warnings
1. For continued safety, do not attempt to modify the circuit
board.
2. Disconnect the AC power and DC Power Jack before
servicing.
1-1-2 Ser vicing the LCD TV
1. When servicing the LCD TV Disconnect the AC line
cord from the AC outlet.
2. It is essential that service technicians have an accurate
voltage meter available at all times. Check the
calibration of this meter periodically.
1-1-3 Fire and Shock Hazard
Before returning the TV to the user, perform the following
safety checks:
1. Inspect each lead dress to make certain that the leads are
not pinched or that hardware is not lodged between the
chassis and other metal parts in the monitor.
2. Inspect all protective devices such as nonmetallic control
knobs, insulating materials, cabinet backs, adjustment
and compartment covers or shields, isolation resistorcapacitor networks, mechanical insulators, etc.
3. Leakage Current Hot Check (Figure 1-1):
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).
Figure 1-1. Leakage Current Test Circuit
4. With the unit completely reassembled, plug the AC line
cord directly into a 120V AC outlet. With the unit’s AC
switch first in the ON position and then OFF, measure
the current between a known earth ground (metal water
pipe, conduit, etc.) and all exposed metal parts,
including: metal cabinets, screwheads and control shafts.
The current measured should not exceed 0.5 milliamp.
Reverse the power-plug prongs in the AC outlet and
repeat the test.
1-1-4 Product Safety Notices
Some electrical and mechanical parts have special safetyrelated characteristics which are often not evident from visual
inspection. The protection they give may not be obtained by
replacing them with components rated for higher voltage,
wattage, etc. Parts that have special safety characteristics are
identified by on schematics and parts lists. A substitute
replacement that does not have the same safety characteristics
as the recommended replacement part might create shock, fire
and/or other hazards. Product safety is under review
continuously and new instructions are issued whenever
appropriate.
1 Precautions
Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock.
1-1 Safety Precautions
DEVICE
UNDER
TEST
TEST ALL
EXPOSED METAL
SURFACES
(READING SHOULD
NOT BE ABOVE 0.5mA)
LEAKAGE
CURRENT
TESTER
2-WIRE CORD
ALSO TEST WITH
PLUG REVERSED
(USING AC ADAPTER
PLUG AS REQUIRED)
EARTH
GROUND
!
1 Precautions
1-2 LA22N21B
1-2-1 General Ser vicing
Precautions
1. Always unplug the unit’s AC power cord from the AC
power source and disconnect the DC Power Jack before
attempting to:
(a) remove or reinstall any component or assembly, (b)
disconnect PCB plugs or connectors, (c) connect a test
component in parallel with an electrolytic capacitor.
2. Some components are raised above the printed circuit
board for safety. An insulation tube or tape is sometimes
used. The internal wiring is sometimes clamped to
prevent contact with thermally hot components. Reinstall
all such elements to their original position.
3. After servicing, always check that the screws,
components and wiring have been correctly reinstalled.
Make sure that the area around the serviced part has not
been damaged.
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. To
avoid a shock hazard, be sure to remove the wrist strap
before applying power to the TV.
2. After removing an ESD-equipped assembly, place it on a
conductive surface such as aluminum foil to prevent
accumulation of an electrostatic charge.
3. Do not use freon-propelled chemicals. These can
generate electrical charges sufficient to damage ESDs.
4. Use only a grounded-tip soldering iron to solder or
desolder ESDs.
5. Use only an anti-static solder removal device. Some
solder removal devices not classified as “anti-static” can
generate electrical charges sufficient to damage ESDs.
4. Check the insulation between the blades of the AC plug
and accessible conductive parts (examples: metal panels,
input terminals and earphone jacks).
5. Insulation Checking Procedure: Disconnect the power
cord from the AC source and turn the power switch ON.
Connect an insulation resistance meter (500 V) to the
blades of the AC plug.
The insulation resistance between each blade of the AC
plug and accessible conductive parts (see above) should
be greater than 1 megohm.
6. 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.
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.
1-3 Electrostatically Sensitive Devices (ESD) Precautions
Some semiconductor (solid state) devices can be easily damaged by static electricity. Such components are commonly called
Electrostatically Sensitive Devices (ESD). Examples of typical ESD are integrated circuits and some field-effect transistors. The
following techniques will reduce the incidence of component damage caused by static electricity.
1-2 Ser vicing 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.
2 Product Specifications
LA22N21B
2 Product Specifications
2-1 Specifications
LCD Panel
TFT-LCD Panel, RGB vertical stripe, normaly Black, 22-Inch viewable, 0.381 mm pixel pitch
Scanning Frequency Horizontal : 30 kHz ~ 68 kHz (Automatic)
Vertical : 56 Hz ~ 85 Hz (Automatic)
Display Colors 16.7 Million colors
Maximum Resolution Horizontal : 1280 Pixels
Vertical : 720 Pixel
Input Video Signal Positive at 75 Ω
Input Sync Signal Type : Seperate H/V
Level : TTL level
Maximum Pixel Clock rate 70 MHz
Active Display
Horizontal/Vertical
AC power voltage & Frequency
AC 100 ~ 264 Volts, 50~60 Hz ± 3 Hz
Power Consumption 80 W
Dimensions (W x H x D)
Set
23.6 x 17.3 x 8.2 Inches (599 X 439 X 209.4 mm) / 23.6 x 16.5 x 4.4 Inches (599 X 418 X 112.7 mm) State of stand disassembled
Package
28.1 x 23.0 x 8.1 Inches (713.0 X 583.0 X 205.0 mm)
Weight
Set / Package 8.98 kg (19.8 lbs) After installation of Stand / 11.0 kg (24.3 lbs)
Environmental Considerations
Operating Temperature : 50 °F ~ 104 °F (10 °C ~ 40 °C)
Operating Humidity : 10 % ~ 80 %
Storage Temperature : -4 °F ~ 113 °F (-20 °C ~ 45 °C)
Storage Humidity : 5 % ~ 95 %
TV System
Antena Input 75Ω
– MAX Internal speaker Out : Right => 5W
Left => 5W
Sound Characteristic
– BASS Control Range : -8 dB ~ + 8dB
– TREBLE Control Range : -8 dB ~ +8 dB
– Headphone Out : 5 mW max (400 m Vrms)
– Output Frequency : 20 Hz ~15.2 Hz
2-1
Item
Description
487.68 mm/ 274.32 mm
Tunning Frequency Synthesize
System NTSC-M
Sound Multi
2 Product Specifications
LA22N21B
2 Product Specifications
2-2
2-2 Pin Assignments
2-2-1 DVI-I (Analog & Digital)
Ref) DVI-D : Digital only
D-SUB : Analog only
Pin
No.
Signal Assignment
Pin
No.
Signal Assignment
Pin
No.
Signal Assignment
1
2
3
4
5
6
7
8
9
10
RX2-
RX2+
GND
NC
NC
DDC Clock (SCL)
DDC Data (SDA)
Analog Vertical Sync.
RX1-
RX1+
11
12
13
14
15
16
17
18
19
20
GND
NC
NC
DDC Input Power(+5V)
IDENT_PC
5V
RX0-
RX0+
GND
NC
21
22
23
24
C1
C2
C3
C4
NC
GND
RXC+
RXC-
Analog Red
Analog Green
Analog Blue
Analog Horizontal Sync.
12345678
9 10111213141516
17 18 19 20 21 22 23 24
C1 C2
C4
C3
DVI-I Receptacle Connector Front View
2 Product Specifications
LA22N21B
2 Product Specifications
2-3
Pin
Separate
1
2
3
4
5
GND
Y
C
GND
GND
RCA Green
RCA Blue
RCA Red
RCA White
RCA Red
Y
GND
Pb (Cb)
GND
Pr (Cr)
GND
Audio L
GND
Audio R
GND
2-2-3 S-Video
2-2-2 Component 1, 2
RCA White
RCA Red
CVBS
Audio L
GND
Audio R
GND
2-2-4 A/V
RCA Yellow
2 Product Specifications
LA22N21B
2 Product Specifications
2-4
2-3 Timing Char t
This section of the service manual describes the timing that the computer industry recognizes as standard for
computer-generated video signals.
2-3-1 LCD Panel Mode1 mode
2 Product Specifications
LA22N21B
2 Product Specifications
2-5
2-3-1 Supported Modes (1)
2 Product Specifications
LA22N21B
2 Product Specifications
2-6
2-3-1 Supported Modes (2)
2 Product Specifications
LA22N21B
2 Product Specifications
2-7
2-3-1 Supported Modes (3)
Memo
2 Product Specifications
LA22N21B
2 Product Specifications
2-8
3 Disassembly and Reassembly
LA22N21B 3-1
3 Disassembly and Reassembly
This section of the service manual describes the disassembly and reassembly procedures for the
LA22N21B monitor.
WARNING: This monitor contains electrostatically sensitive devices. Use caution
when handling these components.
3-1 Disassembly
Cautions : 1. Disconnect the monitor from the power source before disassembly.
2. Follow these directions carefully; never use metal instruments to pry
apart the cabinet.
3. R/Cover opening jig : BH81-00001A
1. Loacte the monitor on the cushioned table
with face down. Remove the stand from
LCD-TV and pull the stand cover.
2. Remove 2 screws from the rear cover and
remove rear cover by using opening jig.
3. Lift up the rear cover and disconnect function
cable, A/V Input cable, IR cable and speaker
cable from the shield. (See illustrations)
4. Remove 2 screws (A/V Input Board) from the
shield. Please add a circle around the 6 screw that
connects the silver shield of the Main-PCB to the
Panel shield.(see illustrations)
5. Lift up main shield and remove 17 screws from
the set (Main Board and Panel Shield).
(see illustrations)
SPEAKER
IR
A/V INPUT
FUNCTION
SPEAKER
!
!
3 Disassembly and Reassembly
3-2 LA22N21B
6. Disconnect cable and lift up the main board and
panel shield. (see illustrations)
7. Lift up the panel.
3-2 Replacement Order of Lamp Assemblies
LCD panal may not be serviced. (Lamps are generally located at top and bottom of panel, which may be
replaced.However,for the Victoria LTA170WP_L01 panel, the lamp is firmly soldered inside of the back
panel. Therefore,servicing the lamp may cause a defective panel.Also,servicing lamp requires front glass
removal, which may cause scratch and/or foreign materials on the glass.)
3-3 Reassembly
Reassembly procedures are in the reverse order of dissasembly procedures.
4 Alignments and Adjustments
LA22N21B 4-1
4 Alignments and Adjustments
4-1 General Alignment Instuction
1. Usually, a color TV-VCR needs only slight touch-up adjustment upon installation.
Check the basic characteristics such as height, horizontal and vertical sync.
2. Use the specified test equipment or its equivalent.
3. Correct impedance matching is essential.
4. Avoid overload. Excessive signal from a sweep generator might overload the front-end
of the TV. When inserting signal markers, do not allow the marker generator to distort
test result.
5. Connect the TV only to an AC power source with voltage and frequency as specified on
the backcover nameplate.
6. Do not attempt to connect or disconnect any wire while the TV is turned on. Make sure
that the power cord is disconnected before replacing any parts.
7. To protect aganist shock hazard, use an isolation transform.
4 Alignments and Adjustments
4-2 LA22N21B
4-2 Factory Mode Adjustments
4-2-1 Entering Factory Mode
1. To enter “Service Mode” Press the remote -control keys in this sequence :
- If you do not have Factory remote - control
- If you have Factory remote - control
4-2-2 Factory Mode Tree
- The buttons are active in the service mode.
1. Remote - Control Key : Power, Arrow Up, Arrow Down, Arrow Left
Arrow Right, Menu, Enter, Number Key(0~9)
2. Function - Control Key : Power, CH +, CH -, VOL +, VOL -,
Menu, TV/VIDEO(Enter)
5 West Europe
4 Alignments and Adjustments
LA22N21B 4-3
[W/B]
RF/AV ComponentDVI-D DVI-A D-TV
Su
b-Brightness ADJ[0~255] 111127 127 127 127
Red Offs
et ADJ[0~255] 128128 128 128 128
Green Offse
t FIX[0~255] 128128 128 128 128
Blue Offs
et ADJ[0~255] 128128 128 128 128
Brightness
[PC Brightness
]
FIX[0~10
0] 45 45 45 45 45
Sub-Cont
rast Fix[0~255] 155110 115 100 115
Red G
ain ADJ[0~255] 128128 128 128 128
Green Gai
n FIX[0~255] 128128 128 128 128
Blue
Gain ADJ[0~255] 128128 128 128 128
TT X Bright
[PC Contras
t]
FIX[0~10
0]
10
0
10
0 100 100 100
[W/B]
RF/AV
Compon
ent DVI-D DVI-A D-TV
Su
b-Brightness ADJ[0~255] 120 125 132132 56
Red Offs
et ADJ[0~255] 127 127 124124 54
Green Offse
t FIX[0~255] 128 128 128128 50
Blue Offs
et ADJ[0~255] 126 126 124124 55
Sub-Contrast Fix[0~255] 133 133 120 120 61
Red Gain ADJ[0~255] 124 124 128128 50
Green Gai
n FIX[0~255] 128 128 128128 50
Blue
Gain ADJ[0~255] 130 130 127127 44
4 Alignments and Adjustments
4-4 LA22N21B
Dithering Off
0E
21
32
2F
4 Alignments and Adjustments
LA22N21B 4-5
4 Alignments and Adjustments
4-6 LA22N21B
4 Alignments and Adjustments
LA22N21B 4-7
32
CSC_OFFSET_Y
CSC_OFFSET_CB
CSC_OFFSET_CR
240
128
128
4 Alignments and Adjustments
4-8 LA22N21B
* Unless otherwise specifid, do not adjust data in Factory Mode.
* Data may be changed for display improvement.
10
3
4 Alignments and Adjustments
LA22N21B 4-9
4-3 White Balance Adjustment
1. In factory mode (1, 3, 6), you can adjust the white balance.
2. As the adjustment and data values differ depending on input sources, different adjustments are requried for RF,
PC/DVI modes.
3. Optimum condition data for each mode are saved as default values. (Refer to Table 2, 3)
4. As the RF mode is applied with the same vlaues as for VIDEO and S-VIDEO, adjustment can be
made in any of RF, VIDEO and S-VIDEO modes.
Table 4-1. White Balance Setting Conditions
RF/AV/COMPONENT
Table 4-2. Color Control Default Vlaue
Table 4-3. Color Control Default Vlaue
4 Alignments and Adjustments
4-10 LA22N21B
4-3-1 Conditions for Measurement
1. On the basis of toshiba ABL pattern : High Light level (57 IRE)
- INPUT SIGNAL GENERATOR : MSPG-925LTH
* Mode NO 1 : 750X480@60 Hz
NO 6 : 1280X720@60 Hz
NO 21 : 1024X768@60 Hz
* Pattern NO 36 : 16 Color Pattern
NO 16 : Toshiba ABL Pattern
2. Optical measuring device : CA210 (FL)
Please use the MSPG-925 LTH generator for model LTP227W.
4-3-2 Method of Adjustment
1. Adjust the basic level of DTV and PC input signals.
a) Set the input to the mode in which the adjustment will be made (PC).
* Input signal - PC Mode : Model #21 (1024*768 Mode), Pattern #16 (Picture 4-1)
b) Enter factory Calibration, confirm the ADC data (PC Mode Only).
* ADC default value : Table 4-3.
2. Adjust the white balance of RF, DTV and PC Modes.
a) Set the input to the mode in which the adjustment will be made (RF DTV PC).
* Input signal - VIDEO Mode : Model #1 (750*480 Mode), Pattern #16
- PC Mode : Model #21 (1024*768 Mode), Pattern #16
b) Enter factory color control, confirm the data.
Picture 4-1 Toshiba ABL Pattern
4 Alignments and Adjustments
LA22N21B 4-11
c) Adjust the low light. (Refer to table 1, 2 in adjustment position by mode)
- Adjust sub - Brightness to set the 'Y' value.
- Adjust red offset ('x') and blue offset ('y') to the color coordinates.
* Do not adjust green offset data.
d) Adjust the high light. (Refer to table 1, 2 in adjustment position by mode)
- Adjust red gain ('x') and blue gain ('y') to the color coordinates.
* Do not adjust the green gain and sub-contrast (Y) data.
Picture 4-2 Toshiba ABL Pattern
Picture 4-3 Toshiba ABL Pattern
Low light
Measurement point
High light
Measurement point
4 Alignments and Adjustments
4-12 LA22N21B
4-3-4 PW565
* Below figures are for contrast adjustment of PW565 (IC565). Do not change the data.
4-3-3 Option Table
* The default settings are most recommended for Option Data. Each data may be adjusted.
4 Alignments and Adjustments
LA22N21B 4-13
4-3-5 VPC 3230-MAIN
* Data may be adjusted.
4-3-6 ADC
*Adjust the R(Pr), G(Y), B(Pb) gain and offset to the basic level of DTV and PC Input signals.
4 Alignments and Adjustments
4-14 LA22N21B
4-3-8 MDIN-150
* Control the specify item that a output signals (RF, CVBS, S-VHS Modes) of MDIN-150 (IC405).
* This data can be changed without notice.
4-3-9 Test Pattern
* Use below test patters to demonstrate the image display of PW565 (IC565).
1) Luma Ramp (16 step)
2) Luma Ramp (128 Step)
3) White 16
4) White 240
5) Color Bar
6) RGB Ramp (32 Step)
4-3-10 Check sum
* XXXX : Displays the current check sum size of the MICOM.
(Varies depending on program update)
4-3-11 Reset
* Initializes the data in the MICOM. (Set to default value)
Use ‘Reset’ to restore adjustmints made in Factory Mode to the original settings.
4-3-12 T_VIC22PEU_0908 02/05/2004 16:04:38
* Displays the MICOM program version
4-3-7 DNIe
* Control the specify item that a output signals of scalar (PW565).
* This data can be changed without notice.
4 Alignments and Adjustments
LA22N21B 4-15
4-4
How to use SW(FlashupgradNT) for LTP227W Set program update
1. Store program practice file in new folder.
2. Connect Set and Jig Cable to execute Program Update.
(Refer to the Picture 4-4 attachment)
3. After completing the JIG Cable connection, store Update practice program (hex file 3EA) in new folder. (guiR,
romcode, factoryGui).
4. Click FlashupgradNT.exe icon 2 times and execute it.
(Upgrader OSD screen is marked)
5. Select OFull.inf in Flash.
(flaher, romcode, guir, factorygui items look in Files To)
Picture 4-4
Picture 4-5
4 Alignments and Adjustments
4-16 LA22N21B
7. After acting No.6, extract Set’s Power Cable and connect it again.
8. During acting No.7, program Update sledding is marked sequentially on OSD screen.
9. After Program Update completion, act NO.7 again.
10. Program Update is completed.
3
2
1
4
<Attachment Picture 4-7 : JIG Cable Connection Explain>
1. Connect with PC Pattern Generator’s output.
(Connect only when you want to see PC screen.)
2. Connect with JIG Output (15 pins) and PC Input (PC/DVI 24 pins) terminal.
3. Connect with COM Port1 of PC (9 Pins).
4. Connect 14V 4.5A Adaptor Cable.
6. Click the “Flash” that is under right of OSD screen.
(if warning message comes out, Click the “Yes”(Y).)
Picture 4-6
Picture 4-7
Loading...