Panasonic TC-L55WT50 Schematic

ORDER NO.MTNC120562CE

B32 Canada: B61

55 inch Class 1080p LCD HDTV

Model No. TC-L55WT50

LA34 Chassis

© Panasonic Corporation 2012.

Unauthorized copying and distribution is a violation of law.

TABLE OF CONTENTS

		PAGE	PAGE
1	Safety Precautions -----------------------------------------------	3
	1.1. General Guidelines ----------------------------------------	3
2	Warning --------------------------------------------------------------	4
	2.1. Prevention of Electrostatic Discharge (ESD)
	to Electrostatically Sensitive (ES) Devices ----------	4
	2.2. About lead free solder (PbF) ----------------------------	5
3	Service Navigation------------------------------------------------	6
	3.1. PCB Layout --------------------------------------------------	6
4	Specifications ------------------------------------------------------	7
5	Technical Descriptions------------------------------------------	8
	5.1. Specification of KEY for DTCP-IP, WMDRM
	and Widevine------------------------------------------------	8
6	Service Mode -------------------------------------------------------	9
	6.1. How to enter into Service Mode ------------------------	9
	6.2. SRV-TOOL-------------------------------------------------	10
	6.3. Hotel mode-------------------------------------------------	11
	6.4. Data Copy by SD Card ---------------------------------	12
7	Troubleshooting Guide----------------------------------------	15
	7.1. Check of the IIC bus lines------------------------------	15
	7.2. Power LED Blinking timing chart ---------------------	16
	7.3. LCD Panel test mode -----------------------------------	16
8	Disassembly and Assembly Instructions---------------	17
	8.1. Disassembly Flow Chart for the Unit ----------------	17
	8.2. Disassembly Procedure for the Unit-----------------	17
9	Measurements and Adjustments --------------------------	32
	9.1. Voltage chart of A-board-------------------------------	32
10	Block Diagram ---------------------------------------------------	33
	10.1. Main Block Diagram -------------------------------------	33
	10.2. Block (1/2) Diagram -------------------------------------	34
	10.3. Block (2/2) Diagram -------------------------------------	35
11	Wiring Connection Diagram ---------------------------------	37
	11.1. Caution statement.---------------------------------------	37
	11.2. Wiring 1 -----------------------------------------------------	37
	11.3. Wiring 2 -----------------------------------------------------	38
	11.4. Wiring 3 -----------------------------------------------------	39
12	Schematic Diagram
13	Printed Circuit Board
14	Exploded View

2

1 Safety Precautions

1.1.General Guidelines

1.When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or damaged by the short circuit.

2.After servicing, see to it that 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.

4.When conducting repairs and servicing, do not attempt to modify the equipment, its parts or its materials.

5.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.

6.When conducting repairs and servicing, do not twist the Fasten connectors but plug them straight in or unplug them straight out.

1.1.1.Leakage Current Cold Check

1.Unplug the AC cord and connect a jumper between the two prongs on the plug.

2.Measure the resistance value, with an ohmmeter, between the jumpered AC plug and each exposed metallic cabinet part on the equipment such as screwheads, connectors, control shafts, etc. When the exposed metallic part has a return path to the chassis, the reading should be 100 Mohm and over.

When the exposed metal does not have a return path to the chassis, the reading must be .

1.1.2.Leakage Current Hot Check (See

Figure 1.)

1.Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.

2.Connect a 1.5kohm, 10 watts resistor, in parallel with a 0.15μF capacitors, 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 an AC voltmeter, with 1000 ohms/volt or more sensitivity, to measure the potential across the resistor.

4.Check each exposed metallic part, and measure the voltage at each point.

5.Reverse the AC plug in the AC outlet and repeat each of the above measurements.

6.The potential at any point should not exceed 0.75 volts RMS. A leakage current tester (Simpson Model 229 or equivalent) may be used to make the hot checks, leakage current must not exceed 1/2 milliamp. In case a measurement is outside 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

3

2 Warning

2.1.Prevention of Electrostatic Discharge (ESD) to Electrostatically

Sensitive (ES) Devices

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically 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 aluminum 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 comparable 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 brushing 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).

4

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 solder. 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. However, Sn+Cu (tin, copper), Sn+Zn+Bi (tin, zinc, bismuth) solder can also be used.

5

3 Service Navigation

3.1.PCB Layout

Board Name	Function
A-Board	Main
K-Board	LED, Cat's eye
P-Board	Power supply, Power switch, Control Button
	Non serviceable.
	P-Board should be exchanged for service.
LP-Board	LOGO LED
LD-Board	LED Drive

6

4 Specifications

Power Source	AC 110-127 V, 60 Hz
Power Consumption
Rated Power	146 W
Standby Power	0.15 W
Display Panel
Panel System	LCD panel (LED backlight)
Screen size	55 inch class (55.0 inches measured diagonally)
W × H × Diagonal	47.9 inch × 26.8 inch × 55.0 inch (1,210 mm × 680 mm × 1,388 mm)
Number of pixels	1,920 × 1,080
Speaker Output	18 W [4 W × 2 + 10 W] ( 10 % THD )
Channel Capability (Digital/Analog) VHF/ UHF: 2 - 69, CATV: 1 - 135		32 °F - 95 °F (0 °C - 35°C)
Operating Conditions	Temperature:
	Humidity:	20 % - 80 % RH (non-condensing)
Connection Terminals
VIDEO IN	RCA PIN (VIDEO, AUDIO-L, AUDIO-R)
COMPONENT IN	RCA PIN (Y, PB, PR, AUDIO-L, AUDIO-R)
HDMI 1/2/3/4	TYPE A Connector (supports [HDAVI Control 5] function)
USB 1/2/3	USB 2.0 Type A connector
PC IN	D-SUB 15PIN (VGA, SVGA, WVGA, XGA, SXGA, WXGA)
DIGITAL AUDIO OUT	PCM / Dolby Digital, Fiber Optic
OTHERS	SD CARD slot, ETHERNET (10BASE-T/100BASE-TX)
Dimensions (W × H × D)	48.7 inch × 31.6 inch × 13.2 inch (1,236 mm × 804 mm × 335 mm)
Including pedestal
TV Set only	48.7 inch × 28.6 inch × 1.1 inch (1,236 mm × 726 mm × 27 mm)
Mass
Including pedestal	43.0 lb. (19.5 kg) NET
TV Set only	37.5 lb. (17.0 kg) NET
Q Wireless LAN
Standard Compliance and	IEEE802.11a/n:
Frequency Range*1,*2	5.15GHz - 5.35 GHz, 5.47GHz - 5.85 GHz
	IEEE802.11b/g/n:
	2.400 GHz - 2.4835 GHz
Access Mode	Infrastructure mode
Security	WPA2-PSK (TKIP/AES)
	WAP-PSK (TKIP/AES)
	WEP (64bit/128bit)

*1 The frequency and channel differ depending on the country.

*2 802.11b/g/n CH1 ~ CH11 only use for United States and Canada.

Q Bluetooth
Standard Compliance	Bluetooth® 3.0
Frequency Range	2,402 GHz - 2,480 GHz

•Use Panasonic 3D Eyewear supporting Bluetooth wireless technology.

•Up to 5 devices can be used simultaneously (except the Touch Pad Controller and the 3D Eyewear).

Note

Design and Specifications are subject to change without notice. Mass and Dimensions shown are approximate.

7

5 Technical Descriptions

5.1.Specification of KEY for DTCP-IP, WMDRM and Widevine

5.1.1.		General information:
1.	EEPROM (IC8902) for spare parts has the seed of KEY for each DTCP-IP for DLNA, WMDRM for Netflix and Widevine for
	CinemaNow.
2.	The final KEY data will be generated by Peaks IC (IC8000) when SELF CHECK was done and are stored in both Peaks IC
	(IC8000) and EEPROM (IC8902).
5.1.2.		Replacement of ICs:

When Peaks IC is replaced, EEPROM should be also replaced with new one the same time. When EEPROM is replaced, Peaks IC is not necessary to be replaced the same time.

After the replacement of IC, SELF CHECK should be done to generate the final KEY data.

How to SELF CHECK: While pressing [VOLUME ( - )] button on the main unit, press [MENU] button on the remote control for more than 3 seconds.

TV will be forced to the factory shipment setting after this SELF CHECK.

8

6 Service Mode

6.1.How to enter into Service Mode

6.1.1.Purpose

After exchange parts, check and adjust the contents of adjustment mode.

While pressing [VOLUME ( - )] button of the main unit, press [INFO] button of the remote control three times within 2 seconds.

6.1.2.Key command

[1]button...Main items Selection in forward direction

[2]button...Main items Selection in reverse direction

[3]button...Sub items Selection in forward direction

[4]button...Sub items Selection in reverse direction

[VOL] button...Value of sub items change in forward direction ( + ), in reverse direction ( - )

6.1.3.How to exit

Switch off the power with the [POWER] button on the main unit or the [POWER] button on the remote control.

6.1.4.Contents of adjustment mode

•Value is shown as a hexadecimal number.

•Preset value differs depending on models.

•After entering the adjustment mode, take note of the value in each item before starting adjustment.

Main item	Sub item	Sample Data	Remark
ADJUST	CONTRAST	000
	COLOR	4C
	TINT	00
	SUB-BRT	800
	BACKLGT	086
	B-Y-G	40
	R-Y-A	00
	V COM	15C
WB-ADJ	R-GAIN	80
	G-GAIN	72
	B-GAIN	75
	R-CENT	7E
	G-CENT	80
	B-CENT	8A
OPTION	Boot	ROM	Factory Preset.
	STBY-SET	00
	EMERGENCY	ON
	CLK MODE	00
	CLOCK	F9E
	EDID-CLK	HIGH
SRV-TOOL		00	See next.

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6.2.SRV-TOOL

6.2.1.How to access

1.Select [SRV-TOOL] in Service Mode.

2.Press [OK] button on the remote control.

6.2.2.Display of SOS History

SOS History (Number of LED blinking) indication.

From left side; Last SOS, before Last, three occurrence before, 2nd occurrence after shipment, 1st occurrence after shipment. This indication except 2nd and 1st occurrence after shipment will be cleared by [Self-check indication and forced to factory shipment setting].

6.2.3.POWER ON TIME/COUNT

Note : To display TIME/COUNT menu, highlight position, then press MUTE for 3 sec.

Time : Cumulative power on time, indicated hour : minute by decimal

Count : Number of ON times by decimal

Note : This indication will not be cleared by either of the self-checks or any other command.

6.2.4.Exit

1. Disconnect the AC cord from wall outlet.

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6.3.Hotel mode

1.Purpose

Restrict a function for hotels.

2.Access command to the Hotel mode setup menu In order to display the Hotel mode setup menu:

While pressing [VOLUME (-)] button of the main unit, press [INPUT] button of the remote control three times within 2 seconds.

Then, the Hotel mode setup menu is displayed.

3.To exit the Hotel mode setup menu Disconnect AC power cord from wall outlet.

4.Explain the Hotel mode setup menu

Item	Function
Mode	Select hotel mode off/on
Input	Select input signal modes.
	Set the input, when each time power is
	switched on.
	Selection:
	-,RF,HDMI1,HDMI2,HDMI3,HDMI4,Comp./
	Video,PC
	• OFF: give priority to a last memory.
Channel	Select channel when input signal is RF.
	Set the channel, each time power is switched
	on.
	Selection:
	Any channel number or [-].
	[-] means the channel when turns off.
Volume	Adjust the volume when each time power is
	switched on.
	Range:
	0 to 100
Vol. Max	Adjust maximum volume.
	Range:
	0 to 100
OSD Ctrl	Restrict the OSD.
	Selection:
	Off/Pattern1
	• Off: No restriction
	• Pattern1: restriction
FP Ctrl	Select front key conditions.
	Selection:
	Off/Pattern1/All
	• Off: altogether valid.
	• Pattern1: only input key is valid.
	• All: altogether invalid.
Pow Ctrl	Select POWER-ON/OFF condition when AC
	power cord is disconnected and then
	connected.
	Off: The same condition when AC power
	cord is disconnected.
	On: Forced power ON condition.

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6.4.Data Copy by SD Card

6.4.1.Purpose

(a)Board replacement (Copy the data when exchanging A-board):

When exchanging A-board, the data in original A-board can be copied to SD card and then copy to new A-board.

(b)Hotel (Copy the data when installing a number of units in hotel or any facility):

When installing a number of units in hotel or any facility, the data in master TV can be copied to SD card and then copy to other TVs.

6.4.2.Preparation

Make pwd file as startup file for (a) or (b) in a empty SD card.

1.Insert a empty SD card to your PC.

2.Right-click a blank area in a SD card window, point to New, and then click text document. A new file is created by default (New Text Document.txt).

3.Right-click the new text document that you just created and select rename, and then change the name and extension of the

file to the following file name for (a) or (b) and press ENTER.

File name:

(a)For Board replacement : boardreplace.pwd

(b)For Hotel : hotel.pwd

Note:

Please make only one file to prevent the operation error.

No any other file should not be in SD card.

12

6.4.3.Data copy from TV set to SD Card

1.Turn on the TV set.

2.Insert SD card with a startup file (pwd file) to SD slot.

On-screen Display will be appeared according to the startup file automatically.

3.Input a following password for (a) or (b) by using remote control.

(a)For Board replacement : 2770

(b)For Hotel : 4850

Data will be copied from TV set to SD card.

It takes around 2 to 6 minutes maximum for copying.

4.After the completion of copying to SD card, remove SD card from TV set.

5.Turn off the TV set.

Note:

Following new folder will be created in SD card for data from TV set.

(a)For Board replacement : user_setup

(b)For Hotel : hotel

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6.4.4.Data copy from SD Card to TV set

1.Turn on the TV set.

2.Insert SD card with Data to SD slot.

On-screen Display will be appeared according to the Data folder automatically.

3.Input a following password for (a) or (b) by using remote control.

(a)For Board replacement : 2771

(b)For Hotel : 4851

Data will be copied from SD card to TV set.

4.After the completion of copying to SD card, remove SD card from TV set.

(a)For Board replacement : Data will be deleted after copying (Limited one copy).

(b)For Hotel : Data will not be deleted and can be used for other TVs.

5.Turn off the TV set.

Note:

1.Depending on the failure of boards, function of Data copy for board replacement does not work.

2.This function can be effective among the same model numbers.

14

7 Troubleshooting Guide

Use the self-check function to test the unit.

1.Checking the IIC bus lines

2.Power LED Blinking timing

7.1.Check of the IIC bus lines

7.1.1.How to access

Self-check indication only:

Produce TV reception screen, and while pressing [VOLUME ( - )] button on the main unit, press [OK] button on the remote control for more than 3 seconds.

Self-check indication and forced to factory shipment setting:

Produce TV reception screen, and while pressing [VOLUME ( - )] button on the main unit, press [MENU] button on the remote control for more than 3 seconds.

7.1.2.Exit

Disconnect the AC cord from wall outlet.

7.1.3.Screen display

7.1.4.Check Point

Confirm the following parts if NG was displayed.

DISPLAY	Check Ref. No.	Description	Check Point
PEAKS	IC8000	PEAKS	A-Board
TUN	TU6706	TUNER	A-Board
AVSW	IC3001	AV SWITCH	A-Board
STBY	IC8000	PEAKS(STM)	A-Board
MEM1	IC8902	PEAKS EEPROM	A-Board
MEM2	IC8900	NAND FLASH	A-Board
ZWEI		ZWEI	LCD PANEL
ID		ID	A-Board
BT	IC8000,A21	Bluetooth	A-Board/Bluetooth
WiFi	IC8000,A20	WiFi	A-Board/WiFi

15

7.2.Power LED Blinking timing chart

1.Subject

Information of LED Flashing timing chart.

2.Contents

When an abnormality has occurred the unit, the protection circuit operates and reset 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.

Blinking Times	Contents	Check point
1	BACK LIGHT SOS	LCD PANEL
		P-Board
3	STM IROM BOOT PROGRAM SOS	A-Board
		P-Board
7	SUB 3.3V SENSE SOS	A-Board
8	SOS (T-CON power)	A-Board
9	SOUND SOS	A-Board
		Speaker
10	ZWEI/FRC SOS	A-Board
12	BE SOS	A-Board
13	EMERGENCY SOS	A-Board
20	2nd BOOT PROGRAM SOS	A-Board
	(Watchdog timer over flow)
21	2nd BOOT PROGRAM SOS	A-Board
	(System error)
22	2nd BOOT PROGRAM SOS	A-Board
	(Main system bus freeze)
23	2nd BOOT PROGRAM SOS	A-Board
	(Accidental interrupt signal)
24	2nd BOOT PROGRAM SOS	A-Board
	(NAND Flash memory data transfer error finish)
25	2nd BOOT PROGRAM SOS	A-Board
	(Unsupported NAND Flash memory)

7.3.LCD Panel test mode

Purpose:

To find the possible failure point where in LCD Panel or Printed Circuit Board when the abnormal picture is displayed.

How to Enter:

While pressing [VOLUME ( - )] button of the main unit, press [OPTION] button of the remote control three times within 2 seconds.

How to Exit:

Disconnect AC plug from wall outlet.

How to confirm:

If the abnormal picture is displayed, go into LCD Panel test mode to display the several test patterns. And then, judge by the following method.

Still abnormal picture is displayed: The cause must be in LCD Panel. Normal picture is displayed: The cause must be in A board.

Remarks:

The test pattern is created by the circuit in LCD Panel.

In LCD Panel test mode, this test pattern is displayed unaffected by signal processing for RF or input signal. If the normal picture is displayed, LCD Panel must be okay and the cause of failure must be in A board.

16

8 Disassembly and Assembly Instructions

8.1.Disassembly Flow Chart for the Unit

This is a disassembly chart.

When assembling, perform this chart conversely.

8.2.Disassembly Procedure for the Unit

8.2.1. Pedestal

8.2.2. WiFi dongle

1.Lay down the unit so that the rear cover faces upward.

2.Remove the 2 screws.

3.Remove the cover.

1.Remove the 1 screw.

2.Remove the WiFi dongle.

4.Remove the 4 screws.

5.Remove the pedestal.

17

8.2.3.BT dongle

1.Remove the 1 screw.

2.Remove the BT dongle.

8.2.4.Rear cover

1.Remove the 33 screws.

2.Remove the 4 M8 CAPs.

3.Remove the rear cover.

8.2.5.P-Board

1.Remove the 1 screw and 1 tab.

2.Remove the key button.

3.Remove the 6 screws.

4.Disconnect the connectors (P2 and P4).

5.Remove the P-Board.

6. Remove the Barrier PCB P.

18

8.2.6.A-Board

1.Remove the 2 screws.

2.Remove the metal AV bracket bottom.

3.Remove the 1 screw.

4.Remove the metal AV bracket side.

5.Remove the 3 screws.

6.Disconnect the connectors (A02, A10, A12 ,A16 ,A20 and A21).

7.Remove the A-Board.

8.2.7.LD-Board

1.Remove the 4 screws.

2.Disconnect the connectors (LD1, LD2, LD3 and LD4).

3.Remove the LD-Board.

19

8.2.8.LP-Board

1.Remove the 1 screw (A).

2.Remove the 8 screws (B).

3.Remove the metal bracket bottom.

4. Remove the bottom cover C.

8.2.9.K-Board

1. Remove the bottom cover L assy.

2.Disconnect the connector (K10).

3.Remove the K-Board.

8.2.10. IR Receiver

1. Remove the bottom cover R.

5.Disconnect the connector (LP10).

6.Remove the LP-Board.

20

2.Disconnect the connector (RM10).

3.Remove the IR Receiver.

8.2.11.Speaker SQ

1.Remove the 4 screws.

2.Remove the 2 speaker SQs.

8.2.12. Speaker thin box

1. Remove the speaker thin box.

8.2.13. Connector bracket BT

1. Remove the 2 tabs and the connector bracket BT.

8.2.14. USB cable

1. Remove the 1 screw and USB cable.

21

8.2.15. Rear Panel T/L/R assy

1. Remove the 6 screws and Rear Panel T/L/R assy.

8.2.16. Rear Panel B assy and LCD Panel

1.Remove the 2 screws.

2.Remove the Rear Panel B assy and the LCD Panel.

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8.2.17. EMI processing

23