Sharp LC-20SH21U - 20" LCD TV User manual

1
LC-20SH21U
SERVICE MANUAL
LCD COLOR TELEVISION
MODEL LC-20SH21U
This document has been published to be used for after
sales service only.
The contents are subject to change without notice.
In the interests of user
-
safety (Required by safety regulations in some countries) the set should be
restored to its original condition and only parts identical to those specified should be used.
SHARP CORPORATION
Page
1. Precautions and Safety Notices………………………….……………….…….2
2. Specifications………………….………………………….……………….….…..5
3. Servicing Environment………………………………….…………………....….6
4. Disassembly of Major Parts……….…….………………………..……….…....7
5. Wiring Diagram……………………..………………………….…………..……12
6. Block Diagram…………………….……………………………..………...…….13
7. Alignment Procedure For White Balance……….…………………..………...14
8. Firmware Upgrade Procedure ……….………………...……………………...22
9. Troubleshooting Analysis………….…………….…………….………….…....23
10. Exploded View……………………………………….………………………..…27
11.Part List………………………………………………………………….…..........29
Contents

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LC-20SH21U
1. Precautions and Safety Notices
Prior to using this manual, please ensure that you have carefully followed all the
procedures outlined in the user manual for this product.
lRead all of these instructions.
lSave this instructions for later use
lFollow all warnings and instructions marked on the product.
lDo not use this product near water.
lThis display should be installed on a solid horizontal base.
lWhen cleaning, use only a neutral detergent cleaner with a soft damp cloth. Do not spray with
liquid aerosol cleaners.
lDo not expose this display to direct sunlight or heat. Hot air may cause damage to the cabinet
and other parts.
lAdequate ventilation must be maintained to ensure reliable and continued operation and to
protect the display from overheating. Do not block ventilation slots and openings with objects
or install the display in a place where ventilation may be hindered.
lDo not allow metal pieces or objects of any kind fall into the display from ventilation holes.
Slots and openings in cabinet and the back or bottom are provided for ventilation. To ensure
reliable operation of the product and to protect it from overheating, these openings must not be
blocked or covered. The openings should never be blocked by placing the product on a bed, sofa,
rug, or other similar surface. This product should not be placed near or over a radiator or heat
register. This product should not be placed in built-installation unless proper ventilation is provided.

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LC-20SH21U
Safety Guidelines
CAUTION: The power supply outlet should be located near the HD TV and should be easily
accessible. Always use the appropriate AC cord that is certified for your specific country. Some
examples are listed below:
USA..................UL Switzerland ..... SEV
Canada.............CSA Britain ............. BASE/BS
Germany..........VDE Japan ............... Electric Appliance Control Act
IMPORTANT NOTICE CONCERNING POWER CORD SELECTION
The specific power cord for this HD TV is enclosed and has been selected according to the country
of destination and must be used to prevent electric shock. Use the following guidelines if it is
necessary to replace the original cord set, or if the cord set is not enclosed. The female receptacle
of the cord set must meet IEC-60320 requirements and should look like Figure A1 below:
Figure A1 Figure A2
For the United States and Canada
In the United States and Canada the male plug is a NEMA5-15 style (Figure A2), UL Listed, and
CSA Labeled. For LCD TVs that are placed on a desk or table, type SVT or SJT cord sets may be
used. For LCD TVs placed directly on the floor, only SJT type cord sets may be used. The cord set
must be selected according to the current rating for the LCD TV. Please consult the table below for
the selection criteria for power cords used in the United States and Canada.
Cord Type Size of Conductors in Cord
Maximum Current Rating of Unit
SJT 18 AWG 16 AWG
14 AWG
10 Amps
12 Amps
12 Amps
SVT 18 AWG
17 AWG 10 Amps 12 Amps

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LC-20SH21U
FCC Compliance Statement
This equipment has been tested and complies with the limits for a Class B digital device, pursuant
to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against
harmful interference in a residential installation. This equipment generates, uses, and can radiate
radio frequency energy, and may cause harmful interference to radio communications if not
installed and used in accordance with the instructions. However, there is no guarantee that
interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment off
and on, the user is encouraged to try to correct the interference by one or more of the following
measures:
•Reorient or relocate the receiving antenna.
•Increase the separation between the LCD TV and receiver.
•Connect the equipment into an outlet on a circuit different from that to which the receiver is
connected.
•Consult the SHARP Service Center or an experienced radio/TV technician for assistance.
FCC Warning
To assure continued FCC compliance, the user must use a grounded power supply cord and the
provided shielded video interface cable with bonded ferrite cores. If a BNC cable is used, use only
a shielded BNC (5) cable. Also, any unauthorized changes or modifications not expressly
approved by SHARP CORPORATION will void the user's authority to operate this device.

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LC-20SH21U
2. Specifications
Model Name LC-20SH21U
Panel Type 20" (20" viewable diagonal area), TFT (Thin Film Transistor),
TN model, 1366x 768 Normally White
Viewing Angles 160° (H) / 140° (V)
Input Signal Video/Audio VGAAnalog * 1 (75 ohms, 0.7 Vp-p)/Mini-Stereo *1
H/V separated (TTL) for PC; fh: 30-48 kHz, fv: 50-75 Hz
HDMI-HDCP *1 / RCA (L/R) stereo *1
TV system antenna / NTSC & ATSC *1 in USA(F type)
YPbPr *1/ RCA (L/R) Stereo *1
AV2 * 1 /RCA (L/R) Stereo *1
Composite * 1 / S–Video *1 / RCA (L/R) stereo * 1
Output Signal RCA (L/R) Stereo * 1;SPDIF (PCM/RAW) *1
HDTV Compatibility 480i, 480P, 720P, 1080i
Video Engine The best TVs use the best technology: ATI inside your TV for The Ultimate Visual Experience.™ Your new Sharp TV is powered by ATI’s Xilleon™ image processing chip
for the true high definition cinematic experience. Enjoy your new Sharp TV with ATI inside.
PC Compatible Recommended 1360x 768@60Hz(reduce blanking)
1280 x 720@60Hz 720 x 400
1024 x 768@60Hz 640 x 480
H = 30~48KHz V= 50~75 Hz
Speaker Output 2.5w (x2 Channels)
Power Voltage 120VAC, 60 Hz, 1.5A
Temperature Operating 0 to + 35° C (Hum. <90%)
(Note A) Storage -20 to+60oC(Hum.< 35%)
Humidity (Relative) Operating 20 to 90% non-condensing. (Ta< 35%)
(Note A) Storage 10 to 90% non-condensing. (NoteA)
Wet-bulb temperature should be 39oCMax. (Ta> 40oC)
Note A: The temperature and relative humidity range is shown in right side
Altitude Operating 0 to 3,000 m
Storage 0 to 12,000m
Dimensions Physical 509mm (W) x 408 mm (H) x203 mm (D)
Weight Net / Gross 6.4 kg / 8.3 kg
Regulations UL/C-UL, FCC-B, UL(UL60065) / C-UL,ICES-003,BETS-T
Consumption
(DC Power)
On
DC OFF
Powersaving
70w(Blue LED)
0.5w(LED off)
14w(Amber LED)
Preset Timing Mode:
Selects timing mode at 1360 x 768 / 60 Hz (reduce blanking) or recommended timing, when you set the graphics card
in your computer.
Note: Product Specifications are subject to change without notice.

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LC-20SH21U
3. Servicing Environment
1. This LCD TV should be used only with the power source type identified on the package and
User’s Guide
2. Service the LCD TV in a room with low humidity and free of dust.
3. Place the LCD TV on a firm, level surface. Subjecting the LCD TV to a drop or sharp impact
may cause severe damage to thin glass, plastic surface materials, and internal components.
4. If necessary, clean the LCD TV with a slightly damp cloth using clean water.
Disconnect the LCD TV from the power source before cleaning. DO NOT use ammonia-based
cleaning products.
5. In the event that the powered LCD rapidly heats, or emits unusual smells or noises,
immediately disconnect the LCD TV From the power source.
6. To avoid electrical hazard, make sure that the LCD TV is fully assembly the casing closed, and
the screws tightened completely before plugging in LCD TV for testing.
7. Internal components of LCD display may be damaged by electrostatic discharge(ESD). Carry
out repairs in an ESD-protected workshop. If no such workshop is available, wear an
antistatic wrist strap or touch a highly conductive metal object.
8. Before opening the housing, disconnect the product from all power source and remove any
connecting cable. If the display has not been disconnected from the power outlet before being
opened, there is a danger to life through electric shock. These is also a risk of damage to the
components

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LC-20SH21U
4. Disassembly of Major Parts
1. Remove the cover hinge.
2. Remove the stand fixing screws (5 pcs ).
3. Remove the Cabinet fixing screws (7 pcs).
4. After opening the Cabinet, remove the cable tie first.

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LC-20SH21U
5. Disconnect the Panel FFC cable connector.
6. Disconnect all the connectors fromthe PWB’s of Cabinet module.

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LC-20SH21U
7. Remove the Inverter PWB fixing screws (4 pcs).
8. Remove the Power PWB fixing screws (4 pcs).
9. Remove the Shield can module fixing screws (6 pcs), then take outthe
shield can module.
10. Remove the Left side IO fixing screws (5 pcs).
11. Remove the Bracket IO fixing screws (4 pcs).

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LC-20SH21U
12. Remove the Right side IO fixing screws (4 pcs).
13. Remove the Main PWB fixing screws (4 pcs).
14. Disconnect all the connectors fromthe PWB’s of Bezel module.

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LC-20SH21U
15. Remove the Key PWB fixing screws (2 pcs).
16. Remove the Audio PWB fixing screws (1 pcs).
17. Remove the Speakers fixing screws (4 pcs).

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LC-20SH21U
5. Wiring Diagram
INVERTER
BD
Main BD
POWER BD
60W
4
PIN
wire
AUO 20” WXGA
T200XW02
8
PIN wire
30
PIN
FFC
6
LAMPS
KEY BD
IR BD
6 PIN
v
The inverter Lamp wire, please c
onnect the
WHITE color wire to CN2/CN7, PINK color wire
to CN3/CN6, BLUE color wire connect to
CN4/CN5.
5 PINwire
AC 120V 60Hz
Panel
CN901
CN1
2pin
CN2 4pin
AC socket 2pin
CN200
1 4pin
CN41
3
CN415
8pin
CN1
8pin
CN301 6pin
CN303 7pin
CN809 5pin
CN9505
10pin CN9506 4pin
CN2
CN3
CN4
CN5
CN6
CN7
SPEAKER
2.5W X 2
4 PIN
5 PINwire
6 PINwire

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LC-20SH21U
6. Block Diagram
4MBITS
EEPROM
M25P40 K9F2808U0C
+3.3V+3.3V
128MBITS
NAND FLASH
IC501,IC502
KEYPAD ADC
CN301
CN303
IR & LED
VGA R/L
HDMI R/L
IC803 HEADPHONE R/L OUT
R/L
CN805
IC811
R
CN809
2
CN609
CN609 CN613
LD1117S
IC2006
FOR TUNER
FOR MCU
5VSB
3.3V
ATI_S/PDIF CN810
3
DEBUG PORT
CN402
JTAG CONNECT
RXD/TXD_B CN404
CN405
FACTORY MODE
RS232 DEBUG
RXD/TXD_C
RESET
IC407
CN407
USB PORT
CN401
JTAG RESET
CN413
CN302
IC401
PROGRAM
ATmeg48
DOENLOAD
IC503
BA9741F
IC2001 1.2V/3A
LD1085
IC2007
5V/5A
AIC1084
IC2003 3.3V
AIC1084
IC2008 1.8V
2.6V
+5V
TVSOUND (SIF)
CN701
CN604
CN601
+3.3V
IC405
FOR ATI & DDR
32K
BY OPTICAL TRANSMITTING
IC813
4052 INPUT2
IC805
ATSC R/L
74HC04
L
IC301
+16V
28Bits LVDS
THC63LVDM83A
24BIT/RGB OUT TMDS*4
IC505
IC802
74LVC125A
1366X768
PANEL
2
TUNER_I2C
2
4052
I2C I2S OUT I2S IN
INPUT1
IC806
AV R/L *2
COMPONENT R/L
4CH
MSP3445G
Micronas
2
ANALOG R/L OUT
COMPONENT
R/L
TPA1517
2
2
I2C INPUT PORT
SPEAKER 3W
Y/PB/PR
VGA
TMDS*4
AD9380
HDMI
3
+5V
+1.8V+3.3V
+1.8V
+2.6V
+3.3V
1.8V/0.37A/0.67W
1.2V/1.8A/2.16W
ATI X240
+1.2V
3.91W
3.3V/0.01A/0.03W
2.6V/0.42A/1.05W
I2S
RGB/24BIT
Microcontroller
+3.3V
TVSOUND (SIF)
PHILIPS/LG LG/0.24A
NTSC+ATSC TUNER
DIGITAL IF
NTSC_CVBS
2
ATmeg88
2UART +3.3V
+5V
+3.3V
+12V
+12V
MC7805
IC2004
5V
IC602
I2C
P/0.42A
TM701/TM702
S/PDIF OUT
AV1
S-Video
AV2 FRONT SIDE
DDR MEMORY
MT46V32M16
+2.6V
64MBYTES

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LC-20SH21U 7. Alignment Procedure for White
Balance
If the Main board or LCD Panel is replaced, white balance alignment must be performed. The
adjustment procedure should be done as following.
Alignment equipment:
1. ASTRO VG859 series.
2. MINOLTA CA210
Please set the LCD TV to enter Factory mode first, then proceed to alignment procedure.
ØPerform ADC CALIBRATION at PC and COMPONENT inputs.
1.PC mode (INPUT5 (PC)).
1.1 Preset condition.
1.1.1 Select in INPUT5 (PC), and analog RGB (D-SUB 15 pin), input 1024x768 / 60Hz
48K (VG859, T#856), 8 x color BAR (100%) + 16 Gray Scale (100%), (VG859,
P#918) (input level 100IRE 0.7Vp-p). See Figure 1
1.1.2 Press “MENU”button to select “Setting”, then enter “Factory Settings”by “Enter”
key, and enter “Calibration”to start perform ADC Calibration.
Fig.1
100% color BAR
100% white BAR

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LC
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20SH21U
1.1.3 After the calibration function ,please check the Gain/Offset value .
1.1.3.1 If the Red, Green, Blue Gain/Offset data are same”127”,it means this
set not yet do the ADC calibration, it must do the calibration function again.
1.1.3.2 If the Red, Green, Blue Gain data are out of the 80-135,Offset data are too
high(near 255) or too low(near 0), it means hardware or test pattern/timing NG.
1.2 32grays pattern check:
1.2.1 Input 1360x768 / 60Hz (reduce blanking), 32 grays scale pattern at 100IRE, adjust
brightness 25, contrast 40 (OSD setting).
1.2.2 In Color Low/Middle/High temp. (6500°K ,9300°K,12000°K)the 32 levels of gray
need be visible.
1.2.3 Input 1360x768 / 60Hz & 32 grays pattern at 100IRE, adjust brightness 25 , contrast
50 (OSD setting).
1.2.4 In Color Low/Middle/High temp. (6500°K ,9300°K,12000°K) 32grays need > 4 level
saturation.

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LC-20SH21U
1.3 Luminance test: (To select “custom mode”by entry “picture setting”)
1.3.1 Input 1360x768 / 60Hz full white pattern at 100IRE.
1.3.2 Adjust contrast & brightness & Backlight to Max., (OSD setting).
the Y > 315cd/m2 ( Bmax ). in color temp. Middle/Low mode,
the Y > 270cd/m2 ( Bmax ). in color temp. High mode.
( 450*0.7=315/450*0.6=270)
2. Component mode (INPUT 3(COMPONENT))
2.1 Input 720P (T#976),8 x color BAR (100%) + 16 Gray Scale (100%), (VG859, P#918)
(input level 100IRE 0.7Vp-p), (see Figure 1).
2.2 Select Setting -> Factory Settings->Calibration then do the ADC Calibration
.2.3 After the calibration function, please check the Gain/Offset value.
2.3.1 If the Red, Green, Blue Gain/Offset data are same”127”, it means this
set not yet do the ADC calibration, it must do the calibration function again.
2.3.2 If the Red, Green, Blue Gain data are out of the 39-88, Offset data are too high
(near 255) or too low (near 0), it means hardware or test pattern/timing NG.

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LC
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20SH21U
2.4 Input 480P (T#978),8 x color BAR (100%)+ 16 Gray Scale (100%),(VG859, P#918)
(input level 100IRE 0.7Vp-p), (see Figure 1).
2.5 2Select Setting -> Factory Settings->Calibration then do the ADC Calibration
2.6 After the calibration function, please check the Gain/Offset value.
2.6.2 If the Red, Green, Blue Gain/Offset data are same”127”, it means this
set not yet do the ADC calibration, it must do the calibration function again.
2.6.3 If the Red, Green, Blue Gain data are out of the 39-88, Offset data are too high
(near 255) or too low (near 0), it means hardware or test pattern/timing NG.
2.7 Grays pattern check:
2.7.2 Input 480P/720P, 32 grays pattern at 100IRE, adjust brightness 25, contrast 40
(OSD setting).
2.7.3 In Color Low/Middle/High temp. (6500°K ,9300°K,12000°K) the 32 grays need
be clear.
2.7.4 Input 480P/720P& 32 grays pattern at 100IRE, adjust brightness 25 , contrast 50
(OSD setting).
2.7.5 In Color Low/Middle/High temp. (6500°K, 9300°K, 12000°K) 32grays need > 4
level saturation.
2.8 Luminance test: (To select “custom mode”by entry “picture setting”)
2.8.2 Input 480P/720P full white pattern at 100IRE.
2.8.3 Adjust contrast & brightness & Backlight to Max., (OSD setting).
the Y > 315cd/m2 ( Bmax ). in color temp. Middle/Low mode,
the Y > 270cd/m2 ( Bmax ). in color temp. High mode.
( 450*0.7=315/450*0.6=270)
ØPerform White Balance Alignment after Finishing ADC Calibration.
n1. Test condition :
a. Measurement point: Center.
b. Measurement direction: Vertical to the screen.

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LC-20SH21U c. Luminance color meter: Minolta CA210 color analyzer.
n2. Check criteria:
There are four user selectable color setting as specified below:
High color temp (12000°K)
x = 0.272 ±0.02 y = 0.278 ±0.02.
Middle color temp (9300°K)
x = 0.286 ±0.02 y = 0.294 ±0.02
Low color temp (6500°K)
x=0.314 ±0.02 y = 0.324 ±0.02
User color temp (9300°K)
x = 0.286 ±0.02 y = 0.294 ±0.02
n3. Adjustment criteria
There are four user selectable color setting as specified below:
High color temp (12000°K)
x = 0.272 ±0.005 y = 0.278 ±0.005.
Middle color temp (9300°K)
x = 0.286 ±0.005 y = 0.294 ±0.005
Low color temp (6500°K)
x = 0.314 ±0.005 y = 0.324 ±0.005
User color temp (9300°K)
x = 0.286 ±0.005 y = 0.294 ±0.005
n4. White Balance adjustment procedure
4.1 Warm up the LCD TV about 30 minutes.
4.2 Set the LCD TV to Factory mode (By OSD), select input source to INPUT 4 (HDMI) and
Set pattern generator to HDMI 1360x768 60Hz timing with white pattern (White signal
level is 90%=90IRE).
4.3 Select custom mode, Contrast = 40, Brightness = 25 (OSD menu).
4.4 Select to High color temp. 12000°K .
4.5 Adjust RGB gain to meet the x=0.272 +/-0.005 and y=0.278+/-0.005.

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LC
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20SH21U
4.6 Select to Middle color temp. 9300K °K .
4.7 Adjust RGB gain to meet the x=0.286 +/-0.005 and y=0.294 +/-0.005.
4.8 Select to Low color temp. 6500 °K .
4.9 Adjust RGB gain to meet the x=0.314 +/-0.005 and y=0.324 +/-0.005.
4.10Exit the Factory mode and Power off/on the LCD TV , then use the item 2 Check
criteria to confirm All INPUT( TV/INPUT1-5) adjustment is well saved.
Note:
1. Do not adjust the RGB offset function.
2. Do not allow to increase RGB gain bigger than 127, only allow to decrease the RGB gain to
meet adjustment criteria.
3. There are at least 1 of RGB gain should be keeps at 127 in each adjusted colors.
ØEntry “Factory Info”mode to check TV set information

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LC-20SH21U
lI/O ports Test:
ØInput 1: Video
Connect the Composite Video to a legacy video device such as a VCR or video game
system.
ØInput 1: S-Video
Connect S-Video to a legacy vi deo device such as a VCR or video game system.If both
terminals are connected, S-Video terminal takes a priority
ØInput 1: Audio (Right / Left)
Connect an external audio source to this jack (Audio (R/L)).This connection supports either
S-Video or Video input.
ØInput 2: Video
Connect the Composite Video to a legacy video device such as a VCR or video game
system.
ØInput 2: Audio (Left / Right)
Connect an external audio source to this jack.
ØInput 3: YPbPr
Connect external video devices with component output to these jacks.
ØInput 3: YPbPr Audio (Left / Right)
Connect an external audio source to this jack.
ØInput 4: HDMI-HDCP
Connect to an external video device such as HD Digital cable/satellite receiver, HD
Set-Top-Box, Media Center PC, or DVD player.
ØInput 4: HDMI Audio (Left / Right)
Connect the audio input if you using a DVI-to-HDMI adaptor.
ØInput 5 (PC IN): Audio
Connect to the Audio out (Green) from a computer.
ØInput 5 (PC IN): Analog RGB
Using a 15-pin VGA cable,connect to a computer or other device with a VGA output.
ØSPDIF Output (Digital Audio Out)
Connect this output to an external stereo audio amplifier, receiver or surround sound
processor with SPDIF optical Input.
ØAudio Output: Right / Left
Connect this output to an external stereo audio amplifier, receiver or surround sound
processorwith R/L audio Inputs.
ØANT.: RF-input
Connect the LCD TV to an over-the-air antenna or cable service to view NTSC or ATSC