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PDP TELEVISION




PH-42HU31S
CONTENTS


Safety instructions...................................................................................... 1
Alignment instruction ................................................................................ 3
Method of software upgrading....................................................................... 6
Working principle analysis........................................................................... 12
Block diagram.............................................................................................13
IC block diagram.........................................................................................14
Wiring diagram ........................................................................................ 19
Troubleshooting guide ................................................................................ 20
Schematic diagram.................................................................................... 23
APPENDIX-A: Assembly list
APPENDIX-B: Exploded View
Attention: This service manual is only for service personnel to take reference with. Before
servicing please read the following points carefully.

Safety precautions
Please read the "Points for attention for the Maintenance & Repair of PDP" and "Criterion for
Identifying the Defects on Screen" as below, before inspecting and adjusting the TV set.

1. "Points for attention for the Maintenance & Repair of PDP"
To avoid possible danger, damage or jeopardy to health and to prevent PDP screen from new
damage, the maintenance people must read the following carefully. If they ignore the following
warnings, there will be deathful risks:
1.1 Screens vary from one model to another and therefore not interchangeable. Be sure to use the
same type of screen in the replacement.
1.2 The operation voltage is approximately 350v for PDP module (including screen, driving circuit,
logic circuit and power module). If you want to conduct maintenance work on PDP module when the
set is in normal operation or just after the power is off, you must take proper measures to avoid
electric shock and never have direct contact or touch with the circuitry of the working module or
metal parts. That's because within a short time relatively high voltage still remains on the capacitor
of the driving part even after the power is off. Make sure to begin relevant maintenance operation at
least one minute after the power is off.
1.3 Don't apply on the module any power supply that is higher than the specification. If the power
supply used deviates from the value given in the specification, there might be a possibility of leading
to fire or damage to the module.
1.4 Never have operation or mounting work under unsuitable environment such as areas in the
vicinity of water (bath room, laundry, water chute of kitchen), sources of fire, heat-radiation parts or
direct exposure to sunlight. Otherwise there will be kickbacks.
1.5 In case foreign substances such as water, liquid, metal slices or others fall into the module
carelessly power must be cut off immediately. Keep the module as it is and do not move anything on
the module. Otherwise it might be possible to contact the high voltage or cause shock short circuit
so that it may lead to fire or electric shock.
1.6 If there is smoke, abnormal smell or sound from the module, please cut the power off
immediately. Likewise in case the screen doesn't work when the power is on or during the
operation, please also cut off the power at once. No more operation in this case.
1.7 Do not remove or plug its connection wire when the module is in operation or right after the
power is off. That's because there remains a relatively high voltage on the capacitor of the
driving circuit. If there is a need to remove or plug in the connection wire, please wait at
least one minute after the power is off.
1.8 Considering the module has a glass faceplate, please avoid extrusion by external force lest
it should cause glass breakage that may get people injured. Two people are needed in
cooperation to move this module lest contingency takes place.
1.9 The complete TV set is designed on the basis of full consideration of thermal dissipation by
convection, with the round hole on the top for heat emission. To avoid overheat, please do
not have any covering on the hole during normal operation and never put it in the place

1
where the space is narrow and in bad ventilation.
1.10 There are quite a number of circuits in PDP that are integrated ones. Please be on guard
against static electricity. During maintenance operation be sure to cover yourself with anti-static bag
and before operation make sure to have it sufficiently grounded.
1.11 There are a big number of connection wires distributed around the screen. Please take care
not to touch or scuff them during maintenance or removing the screen, because once they are
damaged the screen will fail to work and it's not possible to repair it.
If the connection wires, connectors or components fixed by the thermotropic glue need to disengage
when service, please soak the thermotropic glue into the alcohol and then pull them out in case of
damage.
1.12 Connector for the circuit board of the screen part is relatively fine and delicate. Please take
care in the replacement operation lest it should get damaged.
1.13 Special care must be taken during transportation and handling because strenuous vibration
could lead to screen glass breakage or damage on the driving circuitry. Be sure to use a strong
outer case to pack it up before transportation or handling.
1.14 Please put it for storage in an environment in which the conditions are under control so as to
prevent the temperature and humidity from exceeding the scope stipulated in the specification. For
prolonged storage please cover it with anti-moisture bag and have them piled and stored in one
place. The environmental conditions are tabulated as below:

Temperature Scope for operation 0~50centigrade
Scope for storage -15~60centigrade
Humidity Scope for operation 20%~80%
Scope for storage 20%~80%


1.15 If a fixed picture is displayed for a long time, difference in its brightness and color may occur
compared with movable pictures. But it doesn't show any problem and the reason is that there is
reduced density of fluorescent powder in the former. On the other hand, even if changes take place
in the picture, it can keep its brightness for a period of time (several minutes). It's a feature inherent
with plasma and it's not abnormal. However please try as much as possible to avoid showing a still
picture of high brightness for a long time during operation.
1.16 As a digitalized display devise, this module is provided with error diffusion technology and the
gray scale and false enhancement of contour can be displayed by reusing of sub-field. As compared
with cathode ray tube, it can be found in the moving picture that at the brim of the face of a person
there are some wrong colors.
1.17 During the display of graph (indicating the gradual change in brightness horizontally or
vertically) resulting from gray scale test it can be found that the brightness for the two adjacent
levels is uneven. This is caused by the reuse of sub-field, the display of load rectification and the
electrolysis.
1.18 The screen front plate is of glass. Please make sure that the screen has been put in place
during erection. If it is not in place before the erection begins it may lead to screen crack or
breakage.
1.19 Make sure the screw used in the mounting of the screen is of the original specs lest it should
cause damage to the screen due to mismatch. Special care should be taken not to use too long or


2
too big screw.
1.20 Care must be taken to guard against dust during assembling or dismantling, especially to avoid
dirt from falling in between the screen and the glass lest it should harm the receiving and viewing
effect.
1.21 There is piece of insulator stuck on the rear chassis corresponding to the power supply board.
It is used to isolate the cool part from the hot part. Please take care to keep it intact lest it should
become a potential safety trouble.
1.22 In addition to plasma screen, the glass is a part of high value. It has such functions as
anti-radiation, adjustment of color temperature etc. Please handle it carefully.




Alignment instructions
1. Test equipment
PM5518 (video signal generator)
VG-849 (VGA signal generator)
CA210 (white balancer)
2 Alignment flow-chart
The alignment flow-chart is shown as fig-1

Check DDC, HDCP KEY, FLASH and POWER control IC



Combined test for general assembly


Factory initialization setup


IF channel voltage of TV and AGC voltage adjustment


White balance adjustment


Performance check


Preset ex-factory


Fig-1 adjustment flow-chart
3 Unit adjustments
Connect all the boards according to wiring diagram, connect with power and observe the display.
Method for entering factory menu: press "INPUT", "2", "5", "8" and "0" in turn to enter factory menu;
press "CH+" and "CH-" to select adjustment items and press "VOL+" and "VOL-" to adjust value
items, press "MENU" continuously to exit.



3
3.1 Initialization
Enter factory menu, select "OPTION" and "HOTEL OPTION" sub-menu, adjustment of items to see
table1.
Table1 sub-menu adjustment
Items Preset Introduce
HOTEL 0 1: HOTEL OPTION of factory menu is optional
0: HOTEL OPTION of factory menu is not optional
LOGO 1 1: display LOGO in no signal or turn on
0: no LOGO display
ADC PRESCALE 00A Adjust according different power consumption
SIF PRESCALE 000 Adjust according different power consumption
BACK LIGHT 28 Adjust according different screen
ALL COLOR 1 1: white balance of each channel auto offset based on the HDMI white
balance
0: white balance of each channel adjust the offset base separately
ISP 0 0: no unit upgrade on the assembly line
1: unit upgrade on the assembly line
NO STANDY 00 01: turn on; 00: memory function of turn on; 10: standby
INIT VOLUME 0-100 Volume of turn on
INIT CHANNEL 1-200 Channel of turn on
INIT SRC Source Source of turn on
EEPROM-MEMORAY > EEPROM Initialization (operate when EEPROM data chaos)
RECALL


3.2 Adjustment for AFT voltage and AGC voltage of IF channel in TV
3.2.1 IF AFC adjustment
Disconnect J401(B face), input 38.9MHz PAL signal of 80dB from J401 near the socket, Adjust
L404 to value 0.9V of TP402. Enter factory menu, adjust TDA4470 from BG to LL, input 33.9MHz
SECAM signal of 80dB, adjust RP402 to value 0.9V of TP402, then wed J401.
3.2.2 IF AGC adjustment
Input 184.25MHz RF signal of 60DB from RF terminal, adjust RP401 to value 4V of TP404
and there should be no obvious snowy picture. Increase the signal to 90DBV and it should be
display normally and no obvious noise.
3.3 White balance adjustment
3.3.1 white balance adjustment of HDMI
a. Input VG-848 signal from HDMI: TIMING854(800* 600/60Hz) and eighth level gray-scale
signal of PAT920. Use color analyzer CA210 to adjust white balance.
b. Enter submenu of COLOR TEMP., Select 9300k of color temperature
c. Fixed value of B GAIN, adjust R GAIN and G GAIN, let the color coordinate of the seventh
level be 285 and 293. Fixed value of B OFF, adjust R OFF and G OFF, let the color coordinate of
second level be 285 and 293 and the brightness be about 3nit-10nit. Adjustment R GAIN, G GAIN,
R OFF and G OFF repeatedly until the value of the two levels gray-scale be 285 and 293.
3.3.2 VGA/YPBPR/AV white balance check and correct
a. Input VG-848 signal of VGA: TIMING854(800* 600/60Hz) (PATIERN:CROSS) and auto

4
adjust to full screen, then input PAT948 black/white signal, enter factory menu ADC ADJ, select
AUTOTUNE and wait for OK display. Input PAT920(8 gray levels), check if the white balance is
normal, if not, set ALL COLOR to 0 and fine adjust according the method of 3.3.1
b. connect VG-848 signal of YPBPR to YPBPR terminal and input TIMING972(1080i/60HZ)
color bar of PAT908(include black/white bar), Enter submenu of ADC ADJ, Select AUTOTUNE and
wait for OK display. Input PAT920(8 gray levels), check if the white balance is normal, if not, set ALL
COLOR to 0 and fine adjust according the method of 3.3.2
c. Input AV signal(PM5518, 8 gray levels) to VIDEO terminal, check if the white balance is
normal, if not, set ALL COLOR to 0 and fine adjust according the method of 3.3.2
Note: it can't set back to 1 once ALL COLOR changes to 0.
4 Software upgrade
When software upgrading please enter factory menu first, enter ISP of OPTION, set ISP to 1 and
you can begin to upgrade. After upgrade finished, it needs to set ISP back to 0. If the picture can't
display when upgrading, it needs to web J1 of 01S board. Please disconnect J1 again after
upgrading.
5 Performance check
5.1 TV function
Enter searching menu auto search, connect RF-TV terminal with central signal source and check
if the picture is normal, if there are channels be skipped. Check TXT and parental control.
5.2 AV/S, YpbPr terminals
Input AV/S, YPbPr/YCbCr HD signal, check if it is normal.
5.3 VGA terminal
Insert VGA terminal, input VGA format signal of 640X480@60 Hz and check if the display is normal.
5.4 HDMI terminal
Insert HDMI terminal, input signal of 640 X 480@60 Hz signal and check if the display is normal.
5.5 check sound channel
Check the speaker and headphone of each channel.
5.6 RS232 terminal
Insert earphone to COM terminal and check if the long-distance control function is normal.
5.7 other function check
Check the turn on/turn off timer, asleep timer, picture/sound mode, OSD, freeze/mute, stereo, ect.
5.8 presetting before ex-factory

Item Setting Item Setting Item Setting
PICTURE MODE STANDARD BALANCE 50 OSD LANGUAGE English
COLOR MODE NORMAL VOLUME 50 OSD HPOSITION 50
NR WEAK SLEEP TIMER OFF OSD VPOSITION 50
ZOOM FULL TTX LANGUAGE WEST OSD HALFTONE 50
SOUND MODE STANDARD BLUE SCREEN OFF OSD DURATION 15
AVC OFF




5
Method of software upgrading
1. The tools and software demanded
1) Please confirm that PC has the software of ISP_TOOL and install the parallel interface drive
program Port95nt.
2) ISP_TOOL icon is bellow:




3) One serial cable (25 pins) and one VGA cable (15 pins), the serial cable connects the PC and the
upgrade instrument, the VGA cable connects the TV and the upgrade instrument.

2. The steps for upgrading software
1) Please confirm that the connection wires and the upgrade instrument are connected well before
the software written and then power on the TV.
2) Double click the icon ISP_TOOL to open it:




3) Press "Connect" to connect TV, if the connection is done successfully as shown below, then
press "enter".




6
Note: if it appears error, check the connection wires and check if ISP item of the factory menu is set
to 1, if not, please set it to 1.
4) After connection is done, it needs to read the Binary document. Press "Read" as shown below:




5) Search the document needed to write in the "Read" check box.




7
Select




6) Select the document then the window will appear as shown below:



8
7) Press "Auto" to select the writing function.




Select the items shown in the picture above:
(a) Read File
9
(b) Program
(c) Exit ISP
(d) Erase Device
(e) File Area
8) Press "Run" to begin the writing program, wait till the blue bar is complete.




After writing, it will display OK:




If there is error appeared (shown as below), press "Run" again to rewrite the program till it is
success.




10
Note1: keep the connection well and don't cut off the power during the writing process.
Note2: the writing speed can be adjusted as shown below. Select "Config" then adjust Speed BAR,
the value is bigger the speed is faster. But it is easier to appear error when increase the speed, so it
need to select a suitable speed according the PC.




Step 1




Step 2




11
Working principle analysis of the unit
The RF signal received by antenna will be sent to tuner TUN401, then IF signal will be obtained
through high amplifier and mixed frequency, through pre-intermediate amplified by V408, then it will
be sent to acoustic surface-wave Z407 to do IF filter and get better IF characteristics, then it will be
sent to N404 (TDA4470) to do intermediate amplification, phase-locked loop VCO and synchronous
wave detection to get video signal TV-V; after pre-intermediate amplification IF will also be sent to
acoustic surface-wave Z406 to do filter at the same time, then it will be sent to N404 to do
intermediate amplification and output the second sound intermediate frequency signal (TV-SIF).
The TV-V signal output from TDA4470 together with TV-SIF will be sent to main IC
NS4(MST9E88L).
Video signals of AV1/S, VGA, YPbPr and HDMI will be sent to MST9E88L, too.
Video RGB of SCART1 and S-Y, S-C of SCART2 will still be sent to MST9E88L, and the audio
signal of them via audio switch N302(HEF4052BT) selection after also sent to MST9E88L.
The main IC NS4(MST9E88L) is a high performance and fully integrated IC, which can realize
HDMI processing, video demodulating, video switch selection, A/D and D/A conversion,
interlace/de-interlace processing, modes conversion, OSD and low-voltage differential output, ect.
And it also has functions of audio selection, processing and MCU.
The video signal via MST9E88L processing, output 4 pairs differential signal and 1 pair clock
signal for PDP panel display. TV-V output from TDA4470 via double video amplifying, it will be sent
to SCART1 for AV-OUT. AV processed by MST9E88L via double video amplifying will be sent to
SCART2 for AV-OUT, too.
Audio signal via MST9E88L processing will be sent to sound amplifier N405 (MP7722DF)
amplifying to speaker. The audio also sent to earphone amplifier N406(BH3547F) amplifying to
earphone. TV audio signal will be sent to D/A converter NS6(DS4344) through I2S bus converting to
analog audio signal TV-L/R, then sent to SCART1 for AV-OUT. At the same time, TV-L/R together
with AV-L/R processed by MST9E88L will be sent to audio switch NS8(HEF4052BT), after selecting
to SCART2 for AV-OUT.




12
Block diagram

POWER MEG.
ATMEG8L
EDID EDID
24C02 24C02


HDMI DDR

VGA

FLASH
YPbPr HDTV SW.

(DTV) PI5V330
EEPROM

SCART1-RGB LCD TV
SCART1-AV CONTROLLER
HDCP KEY
SCART1-L/R AUDIO SW.
MST9X88LD
HEF4052
SCART2-L/R
SCART2-Y PANEL

SCART2-C

Y/AV1 AUDIO AMP.
S-C MP7722


TUNER SAW


TV-V SPEAKER
IF AMP
TDA4470 TV-SIF


L/R-VGA HP AMP HEAD
L/R-YPbPr BH3547F PHONE
L/R-AV1/S
AV-L/R
SCART1-V OUT 2*AMP TV-IIS
AUDIO SW. SCART2-L/R OUT
HEF4052

SCART2-V OUT 2*AMP CVBS
D/A SCART1-L/R OUT
CS4334 TV-L/R




13
IC block diagram
1. MST9E88L
The MST9E88L is a high performance and fully integrated IC for multi-function LCD monitor/TV with
resolutions up to SXGA/WXGA. It is configured with an integrated triple-ADC/PLL, an integrated
DVI/HDCP/HDMI receiver, a multi-standard TV video and audio decoder, a video de-interlacer, a
scaling engine, the MStarACE-3 color engine, an on-screen display controller, an 8-bit MCU and a
built-in output panel interface. With external frame buffer, 3-D video decoding and processing are
fulfilled for high-quality TV applications. To further reduce system costs, the MST9E88L also
integrates intelligent power management control capability for green-mode requirements and
spread-spectrum support for EMI management.




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2. MP7722DF
The MP7722 is a stereo 20W Class D Audio Amplifier. It is one of MPS'second generation of fully
integrated audio amplifiers which dramatically reduces solution size by integrating the following:
180m power MOSFETs
Startup / Shutdown pop elimination
Short circuit protection
Mute / Standby
The MP7722 utilizes a single ended output structure capable of delivering 2 x 20W into 4speakers.
MPS Class D Audio Amplifiers exhibit the high fidelity of a Class A/B amplifier at efficiencies greater
than 90%. The circuit is based on the MPS' proprietary variable frequency topology that delivers low
distortion, fast response time and operates on a single power supply.




15
16
3. TDA4470
The TDA4470 is an integrated bipolar circuit for multi-standard video/sound IF(VIF/SIF) signal
processing in TV/VCR and multimedia applications. The circuit processed all TV video IF signals
with negative modulation (e.g., B/G standard), positive modulation (e.g., L standard) and the AM,
FM/NICAM sound IF signals.




17
18
Wiring diagram




IF adjust




19
Trouble shooting
1. No raster

Turn-on power supply, check yes
if the red indicator is light in
the STANDBY?

no


Check if PIN3(5V) of main Press POWER button in the red
board is normal? unit or sensor control and
check the indicator.

blue
no
Check if the PIN27 of X304 in
Check STANDBY circuit of
01 board is high-level?
power supply board
yes
no

Replace 01 board

no
Check if the PIN11 of X303 in
Check if Va, Vs of X5203, main board is high-level?
no
X5204 on the power board
is normal yes

yes Replace Check power
N102 supply board
Check the Check the panel
power board




20
2. Raster, but no picture



Check if the unit button Does display OSD yes
yes
and remote control menu in screen when
operation? press menu button?

no
no Check if the all
yes
channels have signal?

no

HDMI/VGA/YPRPB
Enter factory-menu, Which is no signal
initialization EEPROM, of channels
no
Replace then turn off the TV,
main board turn on again, display
TV Replace
picture?
main board
yes

Adjust main board
again
Check if 1VPP signal
yes and noise wave of
X405(PIN 8) in the
TV board?


no


Check if output
Replace TUNER1 no IF signal of
TUNER1(pin
11) is normal?

yes

Check N404 and
its periphery




21
3.no sound

Check if PIN2, 8,13 and Check PIN3 and
yes yes
18 voltage of N405 is PIN7 output wave of Replace N405
normal? N405

no
no

Check power supply
Check PIN62 wave of
yes Replace NS4
NS4



no

yes Replace Z406
Check PIN11 wave of
TUNER1

no

Replace TUNER1




22
page 1 of 4
page 2 of 4
page 3of 4
page 4 of 4
interface connector
KEY board
IR receiver board
TV board
APPENDIX-A: Board List (9342HU3127)

Name No. Main components and its No.

Analog Board 6HU0515310 N404 TDA4470MFL