Panasonic TX-22LT3 User manual

ORDERNO. ITD0310055C2
LCD TV
TX-22LT3
LH12 Chassis
SPECIFICATIONS
Power Source
AC 100~240V, 50/60Hz
Power Consumption
Averageuse: 67W
Stand-bycondition: 1.8W
TV set DC 15V, 3.8Amax.
LCD
22-inch(558 mm), 16:9aspect ratioLCD panel
ScreenSize
486.8mm(W) x273.6mm(H)
Channel Capability-100
UHF: 21-68
Sound
Speaker
4cm, 2pcs, 16
AudioOutput
11W(3.0W+3.0W+5.0W(Woofer)), 10%THD
Headphones
M3(3.5mm) Jack x1
Receiving System/ Band name
PALI
UHFE21 - 68
PAL525/60
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Playback of NTSC tapefromsome PALvideorecorders
(VCR)
M.NTSC
Playback fromM.NTSC Videorecorders (VCR)
NTSC (AV input only)
Playback fromNTSC Videorecorders (VCR)
Aerial-Rear
UHF
Operating Conditions
Temperature: 41°F-95°F(5-35°C)
Humidity: 5%-90%RH (non-condensing)
Connection Terminals
AV1(Scart connecter)
21 Pinsocket (Audio/Videoin, Audio/Videoout, RGB in,
Q-Link)
AV2(Scart connecter)
21 Pinsocket (Audio/Videoin, Audio/Videoout, S-Video
in, Q-Link)
AV3
VIDEO
RCAPIN Type× 1
S-VIDEO
Mini DIN 4-pin
AUDIO L-R
RCAPIN Type× 2
Dimensions(WxD xH)
Including TV Stand
586mm x255mm x428mm
TV Set Only
586mm x96mm x387mm
Weight (Mass)
11kgNet
Note:
Design and Specificationsare subject tochangewithout notice.
Weight and Dimensionsshownare approximate.
2003 Matsushita ElectricIndustrial Co., Ltd. All rights reserved.
Unauthorized copying and distribution isaviolation of law.
1. Safety Precautions
1.1. General Guidelines
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1. When servicing, observe the original lead dress. Ifashort circuit
isfound, replace all parts which have been overheated or
damaged bythe short circuit.
2. After servicing, see to itthat all the protective devices such as
insulation barriers, insulation papers shields are properly
installed.
3. After servicing, make the following leakage current checks to
prevent the customer from being exposed to shock hazards.
1.2. Touch-Current Check
1. Plug the AC cord directlyinto the AC outlet. Donot use an
isolation transformer for thischeck.
2. Connect ameasuring network for touch currents between each
exposed metallicpart on the set and agood earth ground such as
awater pipe, as showninFigure 1.
3. Use Leakage Current Tester (Simpson 228 or equivalent) to
measure the potential across the measuring network.
4. Check each exposed metallicpart, and measure the voltage at
each point.
5. Reserve the AC plug inthe AC outlet and repeat each of the above
measure.
6. The potential at anypoint (TOUGHCURRENT) expressed as
voltage U1and U2, does not exceed the following values:
For a. c.:U1= 35 V(peak) and U2= 0.35 V(peak);
For d. c.:U1= 1.0V,
Note:
The limit value of U2= 0.35 V (peak) fora. c. and U1= 1.0 V ford. c. correspond tothe values 0.7
mA (peak) a. c. and 2.0 mA d. c.
The limit value U1= 35 V (peak) fora. c. correspond tothe value 70 mA (peak) a. c. for
frequencies greaterthan100 kHz.
7. Incase ameasurement isout of the limits specified, there isa
possibilityof ashock hazard, and the equipment shouldbe
repaired and rechecked before itisreturned to the customer.
Figure 1
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2. Prevention of Electro Static Discharge (ESD) to
Electrostatically Sensitive (ES) Devices
Some semiconductor(solidstate) devices canbe damagedeasilybystatic electricity. Such
components commonlyare calledElectrostaticallySensitive (ES) Devices. Examples of typical
ES devices are integratedcircuits and some field-effect transistorsand semiconductor"chip"
components. The following techniques shouldbe usedtohelpreduce the incidence of
component damage causedbyelectrostatic discharge (ESD).
1. Immediatelybefore handling anysemiconductor component or
semiconductor-equipped assembly, drainoff anyESDon your
bodybytouching aknownearth ground. Alternatively, obtainand
wear acommerciallyavailabledischarging ESDwrist strap,
whichshouldbe removed for potential shock reasons prior to
applying power to the unitunder test.
2. After removing an electrical assemblyequipped with ES devices,
place the assemblyon aconductive surface such as alminum foil,
to prevent electrostaticcharge buildup or exposure of the
assembly.
3. Use onlyagrounded-tipsoldering iron to solder or unsolder ES
devices.
4. Use onlyan anti-staticsolder removal device. Some solder
removal devices not classified as "anti-static(ESDprotected)"
can generate electrical charge sufficient to damage ES devices.
5. Donot use freon-propelled chemicals. These can generate
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electrical charges sufficient to damage ES devices.
6. Donot remove areplacement ES device from its protective
package until immediatelybefore you are readyto install it. (Most
replacement ES devices are packaged with leads electrically
shorted together byconductive foam, alminum foil or
comparableconductive material).
7. Immediatelybefore removing the protective material from the
leads of areplacement ES device, touch the protective material to
the chassisor circuitassemblyinto which the device will be
installed.
Caution
Besure no power isapplied to the chassisor circuit, and observe
all other safetyprecautions.
8. Minimize bodilymotions when handling unpackaged replacement
ES devices. (Otherwise hamless motion such as the brushing
together of your clothes fabricor the lifting of your foot from a
carpeted floor can generate staticelectricity(ESD)sufficient
todamage an ES device).
3. Self Check
1. Self-Check isused to automaticallycheck the bus lines and
hexadecimal code of the TV set.
2. To get into the Self-Check mode press the Down( )button on
the customer controlsat the front of the set, at the same time
pressing the Recall button on the remote control, andthe screen
will show :
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If the CCU ports have beencheckedand found tobe incorrect ornot locatedthen“--” will
appearinplace of “O.K.”.
Display Ref. No. Description P.C.B.
MEM IC1004 EEPROM DG-Board
GC2M IC9001 Global Core DG-Board
HAD IC9007 RGB A/D Converter DG-Board
AVSW IC4001 AV selector A-Board
Tun1 TNR001 Tuner B-Board
MSP IC2501 Multi Sound Processor A-Board
LCDMCU IC3002 LCD MCU DG-Board
MEM IC3001 EEPROM DG-Board
PIXL IC6004 Pixel Converter DG-Board
HAD+ IC6003 RGB A/D Converter DG-Board
PNL - LCD Panel -
4. Chasis Board Layout
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BoardName Function
A-Board Main(DC PowerSupply, Audio, Input Select, AV
Connector)
B - Board Tuner
DG - Board Global Core, RGB Processor, MicroProcessor, Pixel
Converter)
K - Board Switch
PD - Board Back Light Inverter
PH - Board Back Light Inverter
V - Board RM, LED
5. Servicing method
5.1. Removing the tiltbase
1. Laydownthe mainunitso that the rear cover faces upward.
2. Remove the AVcablecover.
3. Remove the tuner cablecover.
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4. Remove the fixing screw (1pcs).
5. Remove the hinge cover.
6. Remove the fixing screws(4pcs).
7. Remove the tiltbase.
5.2. Removing the rear cover
1. Remove the tiltbase. (See 5.1.)
2. Remove the fixing screws(9pcs).
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3. Remove the rear cover.
5.3. Removing the shieldplate
1. Remove the rear cover. (See 5.2.)
2. Remove the fixing screws(8psc).
3. Remove the shieldplate.
5.4. Removing the PHshieldplate and the PDshieldplate
1. Remove the shieldplate. (See 5.3.)
2. Remove the fixing screws(5psc).
3. Remove the PHshieldplate.
4. Remove the fixing screws(4psc).
5. Remove the PDshieldplate.
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5.5. Removing the speaker box
1. Remove the shieldplate (See 5.3.)
2. Remove the fixing screwsA(2pcs) and B(2pcs).
3. Remove the angle.
4. Disconnect the coupler(A9), and unlock the cableclamper and
hook to free the cable
5. Remove the speaker box.
5.6. Removing the V-Board
1. Remove the speaker box. (See 5.5.)
2. Disconnect the coupler (A5).
3. Remove the fixing screw (1pcs).
4. Remove the V-Board.
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5.7. Removing the switch unit
1. Remove the shieldplate. (See 5.3.)
2. Disconnect the coupler (K1).
3. Remove the fixing screws(2pcs).
4. Remove the switch unit.
5.8. Removing the K-Board
1. Remove the switch unit. (See 5.7.)
2. Remove the fixing screws(2psc).
3. Remove the K-Board.
5.9. Removing the chassis
1. Remove the PHshieldplate and the PDshieldplate. (See 5.4.)
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2. Remove the V-Board. (See 5.6.)
3. Disconnect the couplers (PH1, PH2, PD1, PD2and DG6900), and
unlock the cableclampers to free the cable.
4. Remove the chassis.
-Disconnecting flexiblecablefrom the coupler. / Lift up both ends
of the cablelock (browncolored) simultaneouslyto release the
locking. Once the flat cableisdisconnected from the coupler, the
cablelock tends to detach from the couplereasily. Due precaution
shouldbe paidon it.
-Reconnecting flexiblecableto the coupler.
Attach the cablelock (brown) to the coupler (white) with its both
ends being pulled up. Insert the flat cableinto the coupler over the
cablelock until the cablestops firmlyat the coupler end. Press
downboth ends of the cablelock until theirupper faces are
positioned flat to lock the cable.
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5.10. Removing the tuner cover and the terminal cover
1. Remove the rear cover. (See 5.2.)
2. Remove the tuner cover.
*The tuner cover lever ispulled up and remove the tuner cover.
3. Remove the fixing screws(4pcs).
4. Remove the terminal cover.
*Ahooks isremoved.
5.11. Removing the B-Board (with tuner assembly)
1. Remove the shieldplate. (See 5.3.)
2. Remove the tuner cover (See 5.10.)
3. Remove the fixing screw (1pcs).
4. Remove the B-Board.
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5.12. Removing the A-Board
1. Remove the shieldplate. (See 5.3.)
2. Remove the angle. (See 5.5.)
3. Remove the terminal cover. (See 5.10.)
4. Remove B-Board. (See 5.11.)
5. Disconnect the couplers (A1,A2, A3and A5).
6. Disconnect the coupler (A9), and unlock the cableclamper to free
the cable.
7. Remove the fixing screws(3pcs).
8. Remove the A-Board.
5.13. Removing the ICHeat Shink
1. Pressing ICHeat Shink Spring and pull up ICHeat Shink.
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5.14. Removing the DG-Board
1. Remove the shieldplate. (See 5.3.)
2. Disconnect the couplers (DG1, DG2, DG3and DG6900).
*When removing coupler (DG6900), cautions are required for the
handling of aconnector. (See 5.9.)
3. Remove the fixing screws(4pcs).
4. Remove the DG-Board.
5.15. Removing the PH-Board
1. Remove the rear cover. (See 5.2.)
2. Remove the PHshieldplate. (See 5.4.)
3. Disconnect the couplers (PH1, PH2and PH3).
4. Remove the fixing screws(2pcs).
5. Remove the PH-Board.
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5.16. Removing the PD-Board
1. Remove the rear cover. (See 5.2.)
2. Remove the PDshieldplate. (See 5.4.)
3. Disconnect the couplers (PD1, PD2, PD3and PD5).
4. Remove the fixing screw (1pcs).
5. Remove the PD-Board.
5.17. Removing the LCD panel
1. Remove the chassis. (See 5.9.)
2. Remove the LCD panel.
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6. Service Mode Function
MPU controls the functions switching foreachIICs through IIC bus inthis chassis. The
following setting and adjustment canbe adjustedbyremote control inService Mode.
6.1. How to enter SERVICE1
1. Insound menu, set BASS to MAXIMUM, and set TREBLE to
MINIMUM.
2. Simultaneouslypress INDEX button on remote control and DOWN
button [ ]on the TV set.
6.2. How to enter SERVICE2
1. Set the channel to CH99.
2. Press HOLDbutton on remote control.
Note:
To exitto Service mode, press Nor Power button on remote control.
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6.3. Option Description
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7. Conductor Views
7.1. A-Board
7.2. DG-Board
7.3. PD-Board
7.4. PH-Board
7.5. B, H1, H2, K, P1 and P2-Board
8. Block and Schematic Diagrams
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