Panasonic TC-32LX70/70 Quick start guide

Panasonic Service and Technology Company
National Training
TC-32LX70/700, TC37LZ85, and TC-32LX85 LCD Display Television
Technical Guide

Prepared by
Jean Magloire
Panasonic Service and Technology Company
National Training
Warning
This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does
not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product. Products
powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service or repair
the product or products dealt with in this service information by anyone else could result in serious injury or death.
Copyright © 2008 by Panasonic Services Company
All rights reserved. Unauthorized copying and distribution is a violation of law.

Table of Contents
3
Subject Page # Subject Page #
Topics 5Self-Check Menu 38
2007 LCD TV Specifications 7Check Point 39
P.C.B Layout (LX700) 8Serviceman Mode 40
P.C.B Layout (LX70) 9Serviceman Mode Menu and Navigation 41
P.C.B Layout (LX700 Pictorial) 10 Adjustment Data 42
P.C.B Layout (LX700 Connectors) 11 SRV-TOOL 43
P.C.B Layout (LX700 LVDS Connector) 12 Voltage chart of AP-board 45
TC-32LX700 Board Description 13 Voltage chart of P and A boards 46
P Board – Main Power Board 15 Voltage chart of DT board 47
Main MPU (Power On Commands) 17 Troubleshooting Signal Problems 49
Standby Operation 19 Picture NG and Sound OK (LX700/LX70 ) 50
SUB Voltages and Over-voltage Protection 21 Picture OK and Sound NG (LX700/LX70) 51
Main Voltages and Over-voltage Protection 22 Picture NG and Sound NG (LX700/LX70 ) 52
Inverter_On Command and Protection 23 No Picture from TV Reception 53
Video Process Block Diagram 25 No Picture 54
Audio Process Block Diagram 27 No Video, Dark Blue Screen 55
MPU SOS Inputs and Blink Codes 29 No Audio 57
Over-Current Protection Circuit 31 No Power 58
Over-Current Protection Circuit 2 33 Power LED Blinks One Time (INV_SOS) 60
Power LED Timing Table 35 Power LED Blinks Three Times (TV_SOS) 61
Self-Check and Reset Function 37 Power LED Blinks Four Times 62

Purposely Left Blank
2008 LCD Television Models 63
Full HD TC-LZ85 & HD TC-LX85 Series 64
Chassis structure (37 Full HD type) 65
Chassis structure (37 HD type) 66
Signal Circuit Block Diagram 67
TC-32LX85 / TC37LZ85 Signal Circuit Block Diagram 68
TC37LZ85 Signal Circuit Block Diagram 69
TC32LX85 Signal Circuit Block Diagram 71
TC37LZ85 Audio Circuit Block Diagram 73
TC32LX85 Audio Circuit Block Diagram 75
Power Supply Overview 77
Power Supply Description 78
Self-Check and Reset Function 80
SOS and Power LED Indication 81
Power LED Blinks 1 Time 82
Power LED Blinks 3 Times 83
Power LED Blinks 4 or 5 Times 84
Power LED Blinks 6 or 7 Times 85
Power LED Blinks 8 or 9 Times 86
Power LED Blinks 1 Time (TC-32LX85) 87
Power LED Blinks 3 Times (TC-32LX85) 88
Power LED Blinks 4 or 5 Times (TC-32LX85) 89
Power LED Blinks 6 or 7 Times (TC-32LX85) 90
Power LED Blinks 8 or 9 Times (TC-32LX85) 91
Picture Defect) 92
Sound Defect 104
Service Information for 2008 models 105
Internal Pattern generator 106
Copy from the TV to the SD Card 109
Copy Data from the SD Card to the TV 115
Copy Self Check Data to the SD Card 117
Local maintenance 120
Picture Refresh Mode 128
Table of Contents
4

1. Models Comparison
2. Boards Layout
3. Power supply/Standby/Power on
4. Troubleshooting
5. SOS Circuit
6. Video/Audio Processing Circuit
7. Panel Drive Circuit
8. Service Man Mode
9. Self-Check
10.Reset
11.Adjustments
12.Service Information for 2008 models
Topics
5

Purposely Left Blank
Purposely left blank
6

2007 LCD TV Specifications
TC-32LX700 TC-32LX70
VIDEO
Screen Size Diagonal (inches) 32 32
Aspect Ratio 16:9 16:9
Number of Pixels 1,049,088 (1,366 x 768) 1,049,088 (1,366 x 768)
Brightness (Panel Luminance) 500 cd/m2 500 cd/m2
Display Capability (1080p, 1080i, 720p, 480P) Y Y
Motion Picture Pro Y —
AUDIO
Speakers Slim squawker x 2, woofer x 2 (L, R) Full-range x 2 (L, R)
Audio Output 20 W (10% THD) 20 W (10% THD)
JACKS
Integrated ATSC Tuner Y Y
SD Memory Card Slot Y (SDHC Compatible) —
HDMI Input 2 2
Composite Video Input 3 (1 side) 3 (1 side)
S-Video Input 2 2
Component Video Input (Y, PB
, PR ) 1 1
Monitor Output 1 1
Digital Audio Output 1 1
Headphone Jack 1 1
7

32/26LX600
AP
P
A
SP
DT
SP V
(HDMI)
KEY Control
P.C.B Layout (LX700)
P.C.B Layout (LX700)
Differences from LX600:
GS board for SD card slot is added.
The inverter PCB of the LX700 is visible.
AP
P
A
SP
DT
SP V
(HDMI)
KEY Control
INV
SP
SP
G
32LX700
GS
SP
G
SP
8

32/26LX60
AP
P
A
SP
DT
SP V
(HDMI)
KEY Control
32/26LX70
P.C.B Layout (LX70)
P.C.B Layout (LX70)
AP
P
A
SP
DT
SP V
(HDMI)
KEY Control
GG
Differences from LX60:
Board structure is almost same.
9

P.C.B Layout (LX700 Pictorial)
P.C.B Layout (LX700 Pictorial)
10 P Board
AP Board DT BoardG Board
GS Board
A Board Inverter PCB
V Board
Key Control

P.C.B Layout (LX700 Connectors)
P.C.B Layout (LX700 Connectors)
11
GS8 A7
G4
A8
A5
A6
P5
P6
P3
CN1
CN501
A9
AP4/A4
AP3/A3
To
Panel
CCFLTs

P.C.B Layout (LX700 LVDS Connector)
P.C.B Layout (LX700 LVDS Connector)
A2
LVDS Connector
Remove the 4 Screws and the metal
plate to expose the LVDS Connector.
A2
LVDS Connector
12

TC-32LX700 Board Description
Board Description Part Number
A-Board Main (Rear Terminal, AV Switch, MCU, Audio &
Video Processor, LVDS) (Exchange Only) TNPH0683S
AP-Board DC-DC, Power Switch TNPA4155ABS
DT-Board Digital Tuner (Exchange Only) TNAG172S
G-Board Video 3, Headphone Jack TNPA4266S
GS-Board SD Card Slot TNPA4206S
V-Board Remote Receiver, LED TNPA4152ADS
P-Board Power (AC/DC) (Exchange Only) TZRXN010MRR
Control Panel
ASSY Control Button (Non-Serviceable, Control Panel Assembly should be exchanged for service.) K0RB00600004
13

Differences from Current models
Differences from Current models
LX600
LX60
Differences from LX600/60:
1. Peaks Lite2 and VIDEO SW are introduced instead of VCTP, FPGA and Peaks Lite .
2. For LX700, HQ1L and LVDS TX are introduced for Motion Picture Pro.
3. HQ1L and LVDS TX are used to convert the picture frames from 60 to 120.
This process helps to reduce after-images.
4. The DT board of the 32LX700 provides Channel Data output only. The
MPEG2 and AC3 (Peaks Lite2) decoders are now part of the A board.
VCTP
HDMI
(CEC)
FPGA
A
ATSC
DT
AUDIO
SWITCH
LX700
LX70
Peaks Lite2
HDMI
(CEC)
HQ1L(*)
A
ATSC
DT
VIDEO
SWITCH
AUDIO
SWITCH
LVDS TX(*)
* 32LX700 only
Peaks Lite
14

P Board
P Board – – Main Power Board Main Power Board
15
T801 D821

P Board
P Board – – Main Power Board Main Power Board
16
When AC is applied to the TV, the Standby circuit of the P board outputs 5Vdc to the AP board. The STB5V
passes through the AP board and enters the A board. On the A board The STB5V is converted to 3.3V to power the system
control circuit for standby operation. The STB3.3V is also applied to the Remote Control receiver and the power LED on the
V board. The MPU (IC1100) of the A board outputs the SUB_ON command to provide a ground connection to relay RL802
of the power supply board. On the AP board, the SUB_ON command is used to turn on a circuit (not shown in the diagram)
that provides STB5V to relay RL802 via pin 15 of connector AP2/P2. When the relay is closed, DC voltage from the rectifier,
approximately 105Vdc, is supplied to the LCD panel for conversion into 24Vdc. The output of the 24V generator passes
through the P board and enters the AP board for conversion into SUB_5V, DTV9V (SUB_9V), and HQ3.3V.
If the power button (main unit or remote control) is not pressed within 25 seconds after applying AC to the unit,
the SUB_ON command goes low to disengage the power relay. When the power button is pressed, the SUB_ON command
goes high to repeat the same operation. The voltages remain present until the unit is turned off.
When the unit is turned on, the LCD panel’s inverter circuit uses the 24Vdc source to generate the 120Vac to
illuminate the CCFLTs. The INV_ON command and the 12Vdc source enter the panel’s drive circuit via the connector
AP2/P2 and P5 of the P board. The inverter circuit is monitored for abnormality. When a defect is detected, a SOS (High)
output is provided to the A board MPU (IC1100) via Connectors P5 and P2/AP2.
Caution: The P board is not to be repaired by you. It is to be exchanged only.

Main MPU (Power On Commands)
Main MPU (Power On Commands)
17

Main MPU (Power On Commands)
Main MPU (Power On Commands)
18
The STB 5V output of the P board passes through the AP board and enters the A board when the unit is
plugged into the AC outlet. IC5702 of the A board converts the STB 5V to 3.3V to power the system control circuit.
Activation of the power switch causes transistor Q5712 to turn off and output STB 3.3V to pin 18 of the MPU. Upon
receiving the STB 3.3V, the MPU (IC1100) outputs the TV-SUB-ON command via pin 8 of connector A4/AP4. The TV-
SUB_ON command is routed to the P board to provide a ground connection for relay RL802 of the power supply board.
On the AP board, The TV_SUB_ON command is used to turn on a circuit (not shown in the diagram) on the A board
that provides STB_5V to relay RL802. As a result , the switch of relay RL802 on the P board closes to allow the output
of 105Vdc to the LCD panel. The TV_Main_ON signal issued by IC1100 appears on pin 6 of connector AP4/A4 to
enable the output of the sound+12V DC/DC converter. Pin 105 of IC1100 outputs the PANEL VCC command to the AP
board to turn on the 12V DC/DC converter. The 12V output is provided to the panel via the P board.
Caution: Measure the 105Vdc source between pin 1 and 3 of connector P3. Hot ground must be used.

Standby Operation
Standby Operation
19

Standby Operation
Standby Operation
20
When the main power switch is activated, it is sensed on the A board by the MPU IC1100. The TV_SUB_ON
signal is subsequently issued in response on pin 8 of connector A4/AP4. It turns on the transistors Q7224 and Q7223 to
output the “Relay voltage on pin 15 of connector AP2/P2. The TV Sub_On signal is also provided to the relay via the
resistor R7208 and pin 17 of connector AP2/P2. This pulls the contacts of the AC relay on the P board. The AC input is
rectified and provided to the LCD panel for conversion into 24Vdc. The 24V is then provided to the inverter circuit of the
LCD panel to produce the 120Vac that powers the backlight CCFLTs. The same 24V passes through the P board and
enters the AP board for conversion into other voltages.
The over-voltage protection circuitry affiliated with each of the regulators located on the AP board monitors
for over-voltage conditions. It is designed to turn off the AC power by disabling the SUB_ON command that turns on the
AC relay.
When an over-voltage condition is detected on the AP board, the voltage at the base of transistor Q7207
goes “high” to turn on Q7207, Q7206, Q7205, and Q7204. The TV_SUB_ON voltage at pin 17 of connector A2/AP2 is now
grounded through Q7204 and the unit shuts down. To turn the unit back on, disconnect and reconnect the AC cord before
pressing the power button.