China PH42HK31 PLASMA Schematic

PDP TELEVISION

PH-42HK31

CONTENTS

Safety precautions………………………………………………………………………..…
Alignment instructions …………………………….…….…………………………………
Working principle analysis of the unit……………………………….………….………….
Block diagram…………………………………..………………………………….…………
IC block diagram………………………………………………………………………..……
Wiring diagram …………………………………………………………………………….
Troubleshooting guide ………………………………………………………………..……
Schematic diagram…………………………………………………………………………
APPENDIX-A: Assembly list
APPENDIX-B: Exploded View

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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 – bathroom, 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 where the space is
narrow and in bad ventilation.

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1.10 There is 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
too big screw.

1.20 Care must be taken to guard against dust during assembling or dismantling, especially to avoid

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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-848 (VGA and HDMI signal generator)
CA210(LCD)/CA-100(PDP) (color analyzer)

2 Alignment flow-chart

The alignment flow-chart is shown as fig-1

Check DDC, HDCP KEY, FLASH and POWER control IC

Factory initialization setup

IF channel AFT voltage of TV and AGC voltage

ADC correction of VGA, YPbPr

White balance adjustment

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.
Method for software upgrading: enter factory menu and select “OPTION”, set ISP to 1 or insert
jump wire J201, then you can upgrade the software on line. After upgrade, it needs to set ISP back
to 0 or pull out jump wire J201. when software upgrade finish, please turn off the TV and then turn
on, enter the factory menu and initialize the EEPROM (EEPROM-MEMORAY RECALL).

Performance check

Preset ex-factory

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3.1 Initialization
The items are only for some units which have special demands. They do not need to be adjusted for
normal units.
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 the power consumption

SIF PRESCALE 001 adjust according the power consumption

BACK LIGHT 100 Adjust according the screen/ this item is not use for PDP

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

NO STANDY 11 01: turn on 00: memory function of turn on 10: standby

INIT VOLUME 0-100 Volume when turn on

INIT CHANNEL 1-200 Channel when turn on

INIT SRC Program source Input Source when turn on

EEPROM-MEMORAY

RECALL

> EEPROM Initialization (operate when EEPROM data chaos)

3.2 Adjustment for AFT and AGC of IF channel in TV

3.2.1 IF AFT adjustment
Turn on the TV then press “INPUT”, “2”, “5”, “8” and “0” to enter the factory menu, set IF VCO to 1,
(or directly press “INPUT”, “2”, “5”, “8”, “1” to enter the adjustment mode), disconnect J601, adjust
L610 to value 2.5V of TP603 on A face (or TP604 on B face)/( the point print “AFT” on B face for
PDP), then wed J601.

3.2.2 IF AGC adjustment
Input 172.25MHz RF signal of 60dB to RF terminal, adjust RP601 to value 3.3V of TP601 on A face
(or TP602 on B face)/(the point print “AGC” on B face for PDP), and there should be no obvious
snowy picture. Increase the TV signal to 90dBV and it should be no obvious noisy.

3.3 White balance adjustment

3.3.1 HDMI white balance adjustment
a. Input VG-848 signal to HDMI: TIMING854(800*600/60Hz), 16 level/8 level (PDP) gray scale

of PAT921/PAT920 (PDP), adjust the balance with CA210/CA-100(PDP).

b. Enter COLOR TEMP sub menu and select color temperature of standard (10000K)

/(11000K for PDP), the value of coordinate is commend.

c. Fixed B OFF, adjust R OFF, G OFF to let the color coordinate of the fourth /second (PDP)

level be (285,293) (CPT panel)/ (280,275) (PDP LG panel); Fixed B GAIN, adjust R GAIN, G GAIN

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to let the color coordinate of the thirteenth /seventh (PDP) level be (285,293) (CPT panel)/ (280,275)
(PDP LG panel). Repeat adjust R OFF, G OFF, R GAIN and G GAIN, until the color coordinate of
the two level gray scale be (285,293) (CPT panel)/ (280,275)(PDP LG panel).

3.3.2 VGA/YPbPr/ AV white balance check and correct

a. Connect VG-848 signal of VGA to VGA terminal and input TIMING854 (800*600/60HZ)
(PATTERN: CROSS), and auto adjust to full screen then input PAT921(16 gray levels), enter
submenu of ADC ADJ, select AUTOTUNE and wait for OK display. Input PAT921(16 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 YPbPr signal to YPbPr terminal and input TIMING972(1080I/60Hz) PAT908
color bar(include back/white bars), enter submenu of ADC ADJ, select AUTOTUNE and wait for OK
display. Input PAT921(16 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

c. Input AV signal of VG-848 to AV terminal, input TIMING968 (480i) PATTERN 921 (16 levels)
and check if the white balance is normal, if not, set ALL COLOR to 0 and fine adjust according the
method of 3.3.1.
Note: it can’t set back to 1 once ALL COLOR changes to 0.

4 Performance check

4.1 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 CCD and V-CHIP for America.

4.2 AV/S, YPbPr terminals
Input AV/S, YPbPr / YCbCr HD signal, check if it is normal.

4.3 VGA terminal
Insert VGA terminal, input VGA format signal of 640X480@60 Hz and check if the display is normal.

4.4 HDMI terminal
Insert HDMI terminal, input 640X480@60Hz signal, check if the display is normal. Check HDCP
function.

4.5 check sound channel
Check the speaker and earphone of each channel.

4.6 RS232 terminal
Insert the earphone wire to COM port, check the long-distance control function with special test
software. (option)

4.7 other function check
Check the turn on/turn off timer, asleep timer, picture/sound mode, OSD, freeze/mute, stereo/SAP,
ect.

4.8 presetting before ex-factory

Item Setting Item Setting Item Setting

PICTURE MODE NAUTRAL

SOUND MODE NEWS

NR LOW HALFTONE 50 ANTENNA CATV

ZOOM FULL DURATION 15 Turn off channel TV

OSD English

VGA/HDMI color

temperature

STANDARD

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4.9 software instruction

No. code model function

N303 5272404002 AT24C04IV-10SU-2.7 HDCP Yes FSX.2A3360-034

N305 5272540003 EN25F40 flash Yes FSX.2A3360-062

N202 5272402002 AT24C02BN10SU-1.8 VGA EDID Yes FSX.2A3360-030

N501 5272404002 AT24C02BN10SU-1.8 HDMI EDID Yes FSX.2A3360-030

N502 5272404002 AT24C02BN10SU-1.8 HDMI EDID Yes FSX.2A3360-030

N503 5272404002

N601 5270008001 ATMEGA8L-8AI Power control Yes FSX.2A3360-061

AT24C02BN10SU-1.8

HDMI EDID Yes FSX.2A3360-030

Flash write

before paste

method

Working principle analysis of the unit

The RF signal received by antenna will be sent to tuner TUNER601, then IF signal will be
obtained through high amplified, mixed frequency. After pre-intermediate amplified by V602, it will
be sent to acoustic surface-wave Z602 to do IF filter and get better IF characteristics, then it will be
sent to N602 (R2S40401) to do intermediate amplification, phase-lock loop VCO and synchronous
wave detection to get the composite video signal TV-CVBS; after pre-intermediate amplification IF
will also be sent to acoustic surface-wave Z601 to do filter at the same time, the it will be sent to
N602 to do intermediate amplification and output the second sound intermediate frequency signal
TV-SIF.

The TV-CVBS and TV-SIF signal will be sent to main IC N304 (MST9U89). Video signal of AV1,
AV2, S-VIDEO, YPbPr1 and YPbPr2 will also be sent to MST9U89, their audio signal via audio
switch N207 (HEF4052BT) selection to MST9U89 (AV1 and S-VIDEO share the same audio jacks).
HDMI1, HDMI2 and HDMI3 via HDMI switch N504 (TMDS351) selection, then sent to MST9U89
together with VGA.

The main IC N304(MST9U89) is a high performance and fully integrated IC, which can realize
HDMI interface processing, video decoding, 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 MST9U89 processing, output 4 pairs differential signal and 1 pair clock
signal for PDP panel display.

The audio signal via MST9U89 processing, it will be sent to N206 (BH3547F) amplifying to
earphone. The audio signal will also sent to sound amplifier N203 (TPA3120) amplifying to speaker.

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Block diagram

P A N E L

I/O port

Power

manage Meg8

DDR

Serial flash

Speaker

D class

amplifier

TPA3120

Earphone

MST9U89CL

HDCP

KEY

Earphone

amplifier

BH3547

EEPROM

HDMI 1

AV 1

HDMI switch

HDMI 2

VGA&L/R

YPrPb1 &L/R

HDMI 3

YPrPb2 &L/R

AV 2

S-VIEDO

R2S10401

TUNER

AV-OUT

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IC block diagram

1. MST9U89BL

The MST9U89BL is a high performance and fully integrated IC for multi-function LCD monitor/TV
with resolutions up to full HD (1920x1080). It is configured with an integrated triple-ADC/PLL, an
integrated DVI/HDCP/HDMI receiver, a multi-standard TV video and audio decoder, two video
de-interlacers, two scaling engines, the MStarACE-3 color engine, an on-screen display controller,
an 8-bit MCU and a built-in output panel interface. By use of external frame buffer, PIP/POP is
provided for multimedia applications Furthermore, 3-D video decoding and processing are fulfilled
for high-quality TV applications. To further reduce system costs, the MST9U89BL also integrates
intelligent power management control capability for green-mode requirements and spread-spectrum
support for EMI management.

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