Panasonic TH-50LFE7U Building instructions

© Panasonic Corporation 2014
Unauthorized copying and distribution is a violation
of law.
ORDER NO.VED1406521CE
D06
FULL HD LCD Display
Model No. TH-50LFE7U
TH-50LFE7W
TH-50LFE7E
LA55 Chassis

2
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
TABLE OF CONTENTS
PAGE PAGE
1 Safety Precautions -----------------------------------------------3
1.1. General Guidelines ----------------------------------------3
1.2. Touch-Current Check (for TH-50LFE7U)-------------3
1.3. Touch-Current Check (for TH-50LFE7W/TH-
50LFE7E) ----------------------------------------------------4
2 Warning --------------------------------------------------------------5
2.1. Prevention of Electrostatic Discharge (ESD)
to Electrostatically Sensitive (ES) Devices ----------5
2.2. About lead free solder (PbF) ----------------------------6
3 Service Navigation------------------------------------------------7
3.1. Service Hint--------------------------------------------------7
4 Specifications ------------------------------------------------------8
5 Service Mode -------------------------------------------------------9
5.1. CAT (Computer Aided Test) mode ---------------------9
5.2. IIC mode structure (following items value is
sample data)----------------------------------------------- 13
6 Troubleshooting Guide---------------------------------------- 14
6.1. Self Check ------------------------------------------------- 14
6.2. No Power--------------------------------------------------- 17
6.3. No Picture -------------------------------------------------- 17
7 Disassembly and Assembly Instructions --------------- 18
7.1. PCB Layout ------------------------------------------------ 18
7.2. Preparation ------------------------------------------------ 18
7.3. About disassembly and replacement --------------- 18
7.4. Backcover Comp removal ----------------------------- 19
7.5. A-Board replacement------------------------------------ 19
7.6. P-Board replacement------------------------------------ 22
7.7. GK-Board and Key Button Bracket
replacement ----------------------------------------------- 22
7.8. Speaker Unit (L) (R) replacement-------------------- 23
7.9. K-Board, LED Panel and LED Panel Case
replacement ----------------------------------------------- 23
7.10. LCD Panel Assy replacement------------------------- 24
8 Block Diagram --------------------------------------------------- 27
8.1. Diagram Notes -------------------------------------------- 27
8.2. Main Block Diagram ------------------------------------- 28
8.3. Block (1 of 2) Diagram ---------------------------------- 29
8.4. Block (2 of 2) Diagram ---------------------------------- 30
9 Wiring Connection Diagram --------------------------------- 31
10 Exploded View and Replacement Parts List ----------- 32
10.1. Exploded View -------------------------------------------- 32
10.2. Packing and Accessories ------------------------------ 33
10.3. Parts List --------------------------------------------------- 34

3
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
1 Safety Precautions
1.1. General Guidelines
1. When conducting repairs and servicing, do not attempt to modify the equipment, its parts or its materials.
2. When wiring units (with cables, flexible cables or lead wires) are supplied as repair parts and only one wire or some of the
wires have been broken or disconnected, do not attempt to repair or re-wire the units. Replace the entire wiring unit instead.
3. When conducting repairs and servicing, do not twist the Fasten connectors but plug them straight in or unplug them straight
out.
4. When servicing, observe the original lead dress. If a short circuit is found, replace all parts have been overheated or damaged
by the short circuit.
5. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly
installed.
6. After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.
1.2. Touch-Current Check (for TH-50LFE7U)
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Connect a measuring network for touch currents between each exposed metallic part on the set and a good earth ground
such as a water pipe, as shown in Figure 1.
3. Use Leakage Current Tester (Simpson 228 or equivalent) to measure the potential across the measuring network.
4. Check each exposed metallic part, and measure the voltage at each point.
5. Reserve the AC plug in the AC outlet and repeat each of the above measure.
6. The potential at any point (TOUCH CURRENT) shall not exceed 0.5 MIU.
7. In case a measurement is out of the limits specified, there is a possibility of a shock hazard, and the equipment should be
repaired and rechecked before it is returned to the customer.
Figure 1

4
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
1.3. Touch-Current Check (for TH-50LFE7W/TH-50LFE7E)
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Connect a measuring network for touch currents between each exposed metallic part on the set and a good earth ground
such as a water pipe, as shown in Figure 1.
3. Use Leakage Current Tester (Simpson 228 or equivalent) to measure the potential across the measuring network.
4. Check each exposed metallic part, and measure the voltage at each point.
5. Reserve the AC plug in the AC outlet and repeat each of the above measure.
6. The potential at any point (TOUCH CURRENT) 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= 1.0 V,
Note:
The limit value of U2= 0.35 V (peak) for a. c. and U1= 1.0 V for d. c. correspond to the values 0.7 mA (peak) a. c. and 2.0
mA d. c.
The limit value U1= 35 V (peak) for a. c. correspond to the value 70 mA (peak) a. c. for frequencies greater than 100 kHz.
7. In case a measurement is out of the limits specified, there is a possibility of a shock hazard, and the equipment should be
repaired and rechecked before it is returned to the customer.

5
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
2 Warning
2.1. Prevention of Electrostatic Discharge (ESD) to Electrostatically Sensi-
tive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Elec-
trostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and
semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage
caused by electrostatic discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your
body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap,
which should be removed for potential shock reasons prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as alumi-
num foil, to prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as “anti-static (ESD protected)” can
generate electrical charge sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most
replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or compara-
ble conductive material).
7. Immediately before removing the protective material from the leads of a replacement ES device, 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 bodily motions when handling unpackaged replacement ES devices. (Otherwise ham less motion such as the brush-
ing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD) sufficient
to damage an ES device).

6
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
2.2. About lead free solder (PbF)
Note: Lead is listed as (Pb) in the periodic table of elements.
In the information below, Pb will refer to Lead solder, and PbF will refer to Lead Free Solder.
The Lead Free Solder used in our manufacturing process and discussed below is (Sn+Ag+Cu).
That is Tin (Sn), Silver (Ag) and Copper (Cu) although other types are available.
This model uses Pb Free solder in it’s manufacture due to environmental conservation issues. For service and repair work, we’d
suggest the use of Pb free solder as well, although Pb solder may be used.
PCBs manufactured using lead free solder will have the PbF within a leaf Symbol PbF stamped on the back of PCB.
Caution
• Pb free solder has a higher melting point than standard solder. Typically the melting point is 50 ~ 70 °F (30~40 °C) higher. Please
use a high temperature soldering iron and set it to 700 ± 20 °F (370 ± 10 °C).
• Pb free solder will tend to splash when heated too high (about 1100 °F or 600 °C).
If you must use Pb solder, please completely remove all of the Pb free solder on the pins or solder area before applying Pb sol-
der. If this is not practical, be sure to heat the Pb free solder until it melts, before applying Pb solder.
• After applying PbF solder to double layered boards, please check the component side for excess solder which may flow onto the
opposite side. (see figure below)
Suggested Pb free solder
There are several kinds of Pb free solder available for purchase. This product uses Sn+Ag+Cu (tin, silver, copper) solder. How-
ever, Sn+Cu (tin, copper), Sn+Zn+Bi (tin, zinc, bismuth) solder can also be used.

7
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
3 Service Navigation
3.1. Service Hint
Board Name Function
P-Board Power supply
Non serviceable.
P-Board should be exchanged for service.
A-Board Digital core signal processor
Non serviceable.
A-Board should be exchanged for service.
GK-Board Key, Power SW
Non serviceable.
GK-Board should be exchanged for service.
K-Board Power LED, Remote receiver, C.A.T.S. sensor
Non serviceable.
K-Board should be exchanged for service.

8
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
4 Specifications
Power Source (U) 110 - 127 V AC, 50/60Hz
Power Source (W, E) 220 - 240 V AC, 50/60Hz
Power Consumption
Rated Power Consumption 95 W
Stand-by condition 0.5 W
Power off condition 0.4 W
Sound
Speakers 25 mm 90 mm 2 pcs
Audio Output 20 W [10 W + 10 W] (10 % THD)
LCD Display panel 50-inch VA panel (LED backlight), 16:9 aspect ratio
Screen size 43.1 inch (1,096 mm) (W) 24.3 inch (616 mm) (H) 49.5 inch (1,257 mm) (diagonal)
(No. of pixels) 2,073,600 (1,920 (W) 1,080 (H))
[5,760 1,080 dots]
Operating condition
Temperature 32 °F - 104 °F (0 °C - 40 °C)
Humidity 20 % - 80 %
Applicable signals
Scanning format 525 (480) / 60i 60p, 625 (575) / 50i 50p, 750 (720) / 60p 50p, 1125 (1080) /
60i 60p 50i 50p 24p 25p 30p 24psF
PC signals VGA, SVGA, XGA, SXGA
UXGA ..... (compressed)
Horizontal scanning frequency 30 - 110 kHz
Vertical scanning frequency 48 - 120 Hz
Connection terminals
AV IN HDMI1 TYPE A Connector 2
HDMI2
DVI-D IN DVI-D 24 Pin Compliance with DVI Revision 1.0
Content Protection Compatible with HDCP 1.1
AUDIO Stereo mini jack (M3) 1 0.5 Vrms, Shared with PC IN
PC IN High-Density Mini D-sub 15 Pin G with sync 1.0 Vp-p (75-ohm)
G without sync 0.7 Vp-p (75-ohm)
B: 0.7 Vp-p (75-ohm)
R: 0.7 Vp-p (75-ohm)
HD / VD:1.0 - 5.0 Vp-p (high impedance)
AUDIO Stereo mini jack (M3) 1 0.5 Vrms, Shared with DVI-D IN
LAN RJ45 10BASE-T/100BASE-TX, compatible with PJLinkTM
SERIAL External Control Terminal
D-sub 9 Pin RS-232C compatible
AUDIO OUT Stereo mini jack (M3) 1 0.5 Vrms
Output level: Variable (- —0 dB) [INPUT 1 kHz / 0 dB, 10 k ohm Load]
CHARGE 5 V/500 mA
Accessories Supply
Remote Control Transmitter N2QAYB000691
Batteries R6 (UM3) Size 2
Dimensions (W H D) 44.4 inch (1,126 mm) 25.7 inch (652 mm) 2.1 inch (53 mm)
Mass (weight) approx. 31.97 lbs (14.5 kg)
Notes:
• Design and specifications are subject to change without notice. Mass and dimensions shown are approximate.
• This equipment complies with the EMC standards listed below. EN55022, EN55024, EN61000-3-2, EN61000-3-3.

9
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
5 Service Mode
5.1. CAT (Computer Aided Test) mode
How to access the CAT mode.
Method A Main unit + remote control operation
Press and hold the button on the rear side of the unit and press the RECALL button on the remote control 3 times quickly
within 2 second, this will place the unit into the CAT mode.
Method B Remote control operation only
1. Set the OFF timer except for [0] minute by OFF TIMER button. (30 minutes, 60minutes, 90 minutes)
2. Set the volume level of sound to 0 by VOL down button / -button.
3. Press the RECALL button more than 3 seconds before a volume display disappears.
To exit the CAT mode, turn the power off by the main unit or a remote control.
5.1.1. IIC mode
Select the IIC mode by Up/Down button on the remote control at the front page of CAT mode and then press the Action button on
the remote control.
Subject and item are mentioned on “IIC mode structure”.
To exit the IIC mode, press the R button on the remote control.

10
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
5.1.2. CD mode
Select the CD mode by Up/Down button on the remote control at the front page of CAT mode and then press the Mute button on
the remote control more than 3 seconds.
Memory data change
To exit the CD mode, press the R button on the remote control.
About the serial number display
As for the serial number of A-module for repair, a dummy value is displayed.
* By the set for which A-module was exchanged, a serial number is displayed as [-----].
About the history display of SOS for the power supply system
• This unit adds the history display (5 times) of power supply failure to the CD mode as PTCT.
• By the self check of a signal system, only one history is displayed (After a self check disappears). But PTCT displays 5 times of
histories (Abnormality of the latest 3 times, first time and second time after shipment) and after a self check does not disappear.
You can see a detailed history of power failure sometimes.
* About the display contents of PTCT
PTCT : The position of [05] is the first time after shipment.
PTCT : The position of [04] is the second time after shipment.
PTCT : The position of [03] is second from last time.
PTCT : The position of [02] is last time.
PTCT : The position of [01] is the latest.
In [Contents & Check point] of [6.1.2. Power LED Blinking timing chart], the two-digit following PTCT are displayed by a hexadeci-
mal number.
Blinking times Contents & Check point Display contents
ex.1 2 times PTCT 02 H 09 02
ex.2 4 times PTCT 04 H 09 04

11
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
5.1.3. SD mode
Select the SD mode by Up/Down button on the remote control at the front page of CAT mode and then press the Action button on
the remote control.
To exit the SD mode, press the R button on the remote control.
5.1.4. MS mode
Select the MS mode by Up/Down button on the remote control at the front page of CAT mode and then press the Mute button on
the remote control more than 3 seconds.
To exit the MS mode, press the R button on the remote control.
Caution:
Market Select should be set after exchange of A-Board.
Destination number
Number Model (Destination)
0 50LFE7J (Japan)
1 50LFE7U (North America)
2 50LFE7E (Europe)
3 50LFE7W (Asia, Oceania, ME, Africa)
18 50LFE7C (China)

12
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
5.1.5. NW mode
Note :
To use the network function, set each "Network Setup" setting and make sure to set the "Control I/F Select" to "LAN".
Select the NW mode by Up/Down button on the remote control at the front page of CAT mode and then press the Action button
on the remote control.
To exit the NW mode, press the R button on the remote control.
5.1.6. ID mode
Select the ID mode by Up/Down button on the remote control at the front page of CAT mode and then press the Mute button on
the remote control more than 3 seconds.
To exit the ID mode, press the R button on the remote control.

13
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
5.2. IIC mode structure (following items value is sample data)

14
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
6 Troubleshooting Guide
6.1. Self Check
6.1.1. Display Indication
1. Self-check is used to automatically check the bus line controlled circuit of the LCD display.
2. To get into the Self-check mode, press the volume down button on the rear side of the unit, at the same time pressing the
OFF-TIMER button on the remote control, and the screen will show.
Method A Self-check only (A shipment setup is not carried out).
• Select the ID mode by Up/Down button on the remote control at the front page of CAT mode and then press the Mute button
on the remote control more than 3 seconds.
Method B Self-check+Shipment setup
• Press and hold the button on the rear side of the unit and press the OFF-TIMER button on the remote control.
If the IIC ports have been checked and found to be incorrect
Or not located then “ - - ” will appear in place of “ OK ”
“ 02 ” in the line of the “ PTCT ” means the number of blinks of the Power LED is 2. (Reference to 6.1.2)
“ H09 ” in the line of the “ PTCT ” is the error code.
To exit the CAT mode switch off the main power.
Note:
The line of the “ PTCT ” displays when you get into the Self-check mode for the first time only after the Power LED blinks.
6.1.2. Power LED Blinking timing chart
1. Subject
Information of LED Blinking timing chart.
2. Contents
When an abnormality has occurred to the unit, the protection circuit operates and resets to the stand by mode. At this time,
the defective block can be identified by the number of blinks of the Power LED on the front panel of the unit.
*Refer to 6.1.1 Display Indication

15
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
6.1.3. LCD Panel test mode

16
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E

17
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
6.2. No Power
First check point
There are following 3 states of No Power indication by power LED.
1. No lit.
2. Green is lit then turns red blinking a few seconds later.
3. Only red is lit.
6.3. No Picture

18
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
7 Disassembly and Assembly Instructions
7.1. PCB Layout
7.2. Preparation
Please spread soft cloth etc. not to damage a screen and
please turn the front of a main part down and lay it down
7.3. About disassembly and
replacement
Cautions when replacing each component
• When you replace each component, please be sure to carry
out according to the following procedure.
• When you attach each module, please do not bolt a screw
strongly.
• The part without the statement of tightening torque, please
tighten a screw 60 ± 10 [N cm].
• To disassemble P.C.B., wait for 1 minute after power was off
for discharge from electrolysis capacitors.
• When tightening a screw, retention structures are required
not to deform the LCD Panel.
• Please remove a clamper and a wire processing tape if
needed in the repair.
• Hold the specified parts to stand the monitor up. (Prevent
from the curvature and deformation of a set)
• In carrying out Section 7.5. or later, please execute the
Chapter 7.4. in advance.

19
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
7.4. Backcover Comp removal
1. Remove the screws, and then remove the Backcover
Comp.
7.5. A-Board replacement
1. Disconnect the connectors and remove the screws.
2. Remove the screws, and then remove the A-Board from
the Terminal Metal.

20
TH-50LFE7U/TH-50LFE7W/TH-50LFE7E
Caution when replacing A-Board
• Gaskets are included with the A-Board for repair.
Please stick the gaskets on the position of the following fig-
ure when replacing the A-Board.