ETEC PH-42FB31, PH-50FB31 Schematic

PDP TELEVISION

PH-42/50FB31

CONTENTS

Safety precautions………………………………………………………………………..…

Criterion for identifying the defects on screen……………………………………………

Alignment instructions …………………………….…….………………………………….

Method of software upgrading……………….…….……………………………………….

Working principle analysis of the unit……………………………….………….………….

Block diagram…………………………………..………………………………….…………

IC block diagram………………………………………………………………………..……

Wiring diagram ……………………………………………………………………………….

Troubleshooting guide ………………………………………………………………..……..

Schematic diagram…………………………………………………………………………..

APPENDIX: Exploded View

1

2

5

8

15

17

18

26
27
38

Note: This maintenance manual is intended only for the reference of the maintenance people.
Please pay attention to the following points before carrying out the maintenance work.

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.

1.10 There is quite a number of circuits in PDP that are integrated ones. Please be on guard against

1

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
dirt from falling in between the screen and the glass lest it should harm the receiving and viewing

2

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.

2. “Criterion for Identifying the Defects on Screen”

The PDP produced by our Company at present uses the following criterion for identifying the
defective points:

2.1 42” Plasma PDP panel:
There may appear three kinds of defective points for this model as shown in Fig.1, i.e., bright spot
(remain bright); dark spot (non-illuminating); flickering spot (continuously flickering).
However they should not exceed the specification as in table 1. Otherwise the product shall be
deemed as sub-standard.

Zone B

H

W/4 W/2 W/4

Figure 1 Defective Points

Table 1 Criterion for Three Kinds of Defective Points

Kind Area A Area B Remark

Dark spots No more than 2 No more than 8

Bright spot No more than 1 No more than 2

Flickering spot No more than 1 No more than 2

2.2 50” Plasma PDP panel:

There may appear three kinds of defective points for this model as shown in Fig.2 i.e., bright spot
(remain bright); dark spot (non-illuminating); flickering spot (remain flickering).
However they should not exceed the specification as in table 2. Otherwise the product shall be

Zone A

W

H/4

H/2

H/4

Total number of defective
points in A and B shall not
exceed 8. The distance
between two defective
points shall not be shorter
than 15mm.

3

deemed as sub-standard.

H

Zone B

Zone A

W

H/4

H/2

H/4

Item Kind Area A Area B Remark

1 Dark spots No more than 4 No more than 10

2 Bright spot No more than 1 No more than 3

W/4 W/2 W/4

Total number of defective
points in A and B shall not
exceed 14. The distance

3 Flickering spots No more than 1 No more than 3

between two defective points
shall not be shorter than
10mm.

Figure 2 Defective Points

Table 2 Criterion for Three Kinds of Defective Points

4

Alignment instructions

1. Test equipment

PM5515 (video signal generator)
VG-849 (YUV, VGA, HDMI signal generator)
CA100 (white balancer)

2. The alignment flow chart (see below figure)

Connect with central signal source, then check each function of TV such as

station missing, analog control etc., check the output of headphone and speaker

Input AV/SVIDEO signal, then check each function of all the terminals

Input HD signal (format), then check each function of the terminal

Input VGA, HDMI signal, check if the display is normal, check each

function such as analog control etc., check horizontal /vertical center etc.

3. Description of adjustment

3.1 Unit adjustment

To produce digital board and analog board

Check the accessories and pack them in box

Fig-1 adjustment flow-chart

Check DDC and FLASH

All testing

Adjust white balance

Preset ex-factory

Connect the digital processing board, analog board, power board, power filter board and button
board according to the wiring diagram. Connect with power and observe the display.

3.2 Method for using factory menu

Press ”Source” button, then press”2580” to enter level one factory menu. Press ”▲” and “▼“ to

5

select adjustment page, then press “OK” to access. Press “▲” and “▼“ to move cursor up and down,
when the cursor stays on a certain adjustment item, you can adjust it according the prompt. Press
“MENU” exit to the level one factory menu; press “MENU” again to exit from the factory menu. The
adjustment item is list as table 3.

Table 3 adjustment item

No. Item Specification

1 Factory Preset Reset to the default data

2 Spatial NR

3 Speckel NR

4 Temporal NR

5 White Balance White balance adjustment

6 Auto Color A/D correction

7 DTV Manual Scan If search DTV at manual scan, default= Off

3.3 adjustment of white balance

3.3.1 input 16 level gray-scale signal from VG849 to HDMI channel (TMIING: select a support
format of HDMI), enter white balance adjustment page of factory menu, select cool color
temperature of item, fixed GG to 5000, adjust RG, BG, let the color coordinate of third level on the
right be (270,283) at 120nits; fixed BO to 5000, adjust RO, GO, let the color coordinate of third level
on the left be (270,283) at 5nits. The brightness of 120nits and 5nits may obtain by adjusting the
contrast and brightness of menu.

Noise reduce setting, the preset data of each
channel is different, please don’t change it.

3.3.2 input 16 level gray-scale signal from VG849 to AV channel (TMIING:968), enter white balance
adjustment page of factory menu, select cool color temperature of item, fixed GG to 5000, adjust
RG, BG, let the color coordinate of third level on the right be (270,283) at 120nits; fixed BO to 5000,
adjust RO, GO, let the color coordinate of third level on the left be (270,283) at 5nits. The brightness
of 120nits and 5nits may obtain by adjusting the contrast and brightness of menu.

3.3.3 input 16 level gray-scale signal from VG849 to VGA channel (TMIING: select a support format
of VGA), enter white balance adjustment page of factory menu, select cool color temperature of
item, fixed GG to 5000, adjust RG, BG let the color coordinate of third level on the right be (270,283)
at 120nits; fixed GO to 5000, adjust RO, BO, let the color coordinate of third level on the left be
(270,283) at 5nits. The brightness of 120nits and 5nits may obtain by adjusting the contrast and
brightness of menu.

3.3.4 input 16 level gray-scale signal of 480P from VG849 to YPbPr channel, enter white balance
adjustment page of factory menu, select cool color temperature of item, fixed RG, GG, BG to 5000,
and RO to 5000, adjust RO, BO, let the color coordinate of third level on the left be (270,283) at
5nits. The brightness of 5nits may obtain by adjusting the contrast and brightness of menu.

Note: the white balance adjustment of VGA and YPBPR must be done at the situation that the white
balance adjustment of HDMI is accurate.

4 Performance check

4.1 TV function

Connect RF-TV terminal to the central signal source, enter the setup menu→ auto search, check if
there is station skipping, the output of earphone and speaker, the picture are normal. Especially
check the signal of PAL and DVB-T, check if the S/PDIF output of DVB-T is normal.

4.2 AV/S-VIDEO terminal

Input AV/S signal, check if the picture and sound are normal. The main system is NTSC and PAL.

6

4.3 YPbPr/YCbCr terminal

Input YUV signal (VG-849 signal generator), separate input YUV format signal of table 4 and check
if the picture and sound are normal.

Table 4 YUV signal format

No H-frequency (KHz) V-frequency (KHz) Signal

15.734 59.94 SDTV 480i

1

2 31.469 59.94 HDTV 480p

3 44.955 59.94 HDTV 720p

33.716 59.94 HDTV 1080i

4

15.625 50 SDTV 576i

5

31.25 50 HDTV 576p

6

37.5 50 HDTV 720p

7

4.4 VGA terminal

Input VGA signal (VG-849 signal generator), separate input VGA format signal of table 3 and check
if the picture and sound are normal. If the image is deflection of the H/V-field, select manual
correction of Advanced Video Menu.

4.5 HDMI terminal

HDMI signal format receives the 8 high-definition signals: 480I, 480P, 720P/60 Hz, 1080I/60 Hz,
576I, 576P, 720P/50Hz,1080I/50Hz except for the table 5 signal. Separate input the signals from
VG-849. Check if the image (contain HDCP ON and OFF) and sound are normal, if the output of
S/PDIF is normal.

Table 5 VGA signal format

No Resolution H-frequency(kHz) V-frenquency(Hz)

1 720 X 400 31.469 70.086 28.322 IBM

2 640 X 480 31.469 59.94 25.175 IBM

3 640 X 480 37.861 72.809 31.5 VESA

4 640 X 480 37.5 75 31.5 VESA

5 640 X 480 43.269 85.008 36 VESA

6 800 X 600 35.156 56.25 36 VESA

7 800 X 600 37.879 60.317 40 VESA

8 800 X 600 48.077 72.188 50 VESA

9 800 X 600 46.875 75 49.5 VESA

10 800 X 600 53.674 85.061 56.25 VESA

11 1024 X 768 48.363 60.004 65 VESA

12 1024 X 768 56.476 70.069 75 VESA

13 1024 X 768 60.023 75.029 78.75 VESA

Point clock pulse

frenquency(MHz)

Remark

5 Ex-factory setting of user menu

1) Select TV channel, volume: 40

2) Video menu, Picture Mode: Vivid ( other items: Mild, Custom, Standard), Aspect Ratio: Wide

3) Video menu, Advanced Video Menu:

7

Color Temperature: Cool

4) Audio menu, Audio Mode: Speech(other items: Custom, Music, Movie)
Balance: 50, SPDIF Mode: Auto, HP Volume:50

5) Rate menu, Rating: No Block, Parent Lock: off

6) System menu, State: NSW/ACT(other items: VIC, QLD, SA, WA, TAS, NT)

Note: the default password of Rate menu is”0000”

Method of software upgrading

1. Connect RS-232 cable to computer and TV set. The cable must be a female to female

RS-232 cable, and the line is TXD to RXD and RXD to TXD cross-link. It’s popular for PC to

PC connection.

2. If the computer has no RS-232 serial port(e.g. Notebook PC),you needs a additional USB to

serial port cable.

8

3. Copy the update tools (iDev.exe) to the path you want to do it, and double click it.

4. Select “setup” menu.

9

5. Confirm the Serial port is right. Base on the port which using for update. And set the band rate to

115200 (default).

6. Select the “Image path” menu.

10

7. Confirm it’s the right file.

8. If it’s not right(Maybe you didn’t select it before),click the “…”button to select “*.ecc” file.

Sometimes the image file you got it will be “*.rar ”or “*.zip” zip file, needs unzip it first.

9. You also can click the setup button to select and config, but please don’t select the red

one(update boot sector).

11

10. Then click the “down” button.

12

11. You can see the “waiting” window.

12. Then power (off then) on the TV set.

13. After download, it will be burning.

13

14. Last it will be finished

15. Press the (IR/ locate keypad) power key and holding for several second to force power off TV

set, then power on again. It would be ok now. If it’s failure you can try once again.

14

Working principle analysis of the unit

Feature:

1. PDP PANEL

SIZE: 42” 50”
Pixel Rate:1024X768 1366X768
Interface: LVDS(Single 24bits)

2. SIGNAL FEATURES

TV: PAL-BG / DVB-T
RF Frequency Range:46.25~855.25MHz
PC Max. Resolution: Up to 1280 x 1024 60Hz
PC Max. Pixel Rate:110MHz
COMPONENT:480i,480p,576i,576p,720p/50Hz,
1080i/50Hz,720p/60Hz,1080i/60Hz
HDMI Max. Resolution: Up to 1920 x 1080i
HDMI Data Protection: HDCPv1.1

3. OSD FEATURES

Size: Full Screen Size
Color: 24bit True Color
Type: Graphical & Text UI
Language: English

4. CONNECTION FEATURES

VIDEO INPUT: AV X2, S-VIDEO X1, RGB(PC) X1, COMPONENT X2, HDMI X1.
AUDIO INPUT: AV X2, RGB(PC) X1, COMPONENT X2.
VIDEO OUTPUT: AV OUT X1.
AUDIO OUTPUT: Audio Out x 1, S/PDIF X1, Earphone X1, Speaker Out x 2.
TV INPUT: RF X1
Service(input):RS-232 X1

5. OTHERS

Wide power voltage range, low power consumption at standby(≤1W)
Digital decoder with 3D comb filter
High efficiency D class audio amplifier, high quality output
Wide power voltage input: AC110V-240V,50HZ/60HZ

15

Working principle

1. PAL-BG signal flow:

Antenna reception PAL-BG signal send to the integrative tuner FQD1216, which contains HF and IF
amplifier circuit and video decoding circuit. It is controlled by main IC ZR39660 (inside CPU)
through I2C bus. The PAL-BG signal via frequency tuning, HF amplification, IF amplification, system
switching and decoding, output video signal TV-CVBS of 1Vpp and sound IF signal (SIF).
TV-CVBS and AV1-CVBS, AV2-CVBS input from AV terminal, via switch IC HEF4052 to output
signal, one way send to ZR39660 for VEDIO DECODER, DEINTERLACE and SCALER, then send
to LVDS level drive for LCD screen, another way is output through AV output socket as AV OUT.
The sound IF (SIF) is fed into demodulation IC SGTV5810, via demodulate, pre-amplify, woof adjust
and volume control, output left/right sound signal to digital audio amplifier TPA3001 amplify, then
send to speaker.

2. DVB-T signal flow:

Antenna reception DVB-T signal send to tuner FQD1216, after frequency tuning, HF amplification,
IF amplification and SAW FILTER, output IF signal to demodulation chip DRX3975, via QAM
demodulation, fed to ZR39660 for information source decoding in the format of standard serial TS
stream.
HD video signal via decoding to A/D conversion and OSD superposition, at last send to LVDS drive
level for PDP panel.
HD audio signal, via decoder built-in ZR39660, resumed to multi- channel sound of Dolby AC-3, at
the same time output data stream of I2S format and S/PDIF data stream. Audio data of I2S format is
fed to audio D/A conversion chip CS4345 to output analog L/R signal. S/PDIF data stream directly
output from optical fiber interface.

3. PC/YPrPb signal flow

PC and two YPBPR signal via matched resistance, it a-c couple to Triple Video A/D Converter
TDA8759 A/D conversion. Send B/G/B of 24 bit to main IC ZR39660 digital decode, image scale
and OSD superposition, then send to LVDS level drive for LCD screen.
Sound signal (PC, YPrPb) via matched resistance and a-c couple, it send to SGTV5810 (sound
processing and volume control) switch of audio. Select right/left sound channel, their send to digital
sound amplifier TPA3001 amplify, then send to speaker.

4. HDMI signal flow

HDMI video signal is directly fed to main IC ZR39660 (with HDCP function of HDMI) digital decode,
image scale and OSD superposition, then output LVDS drive level for screen.
HDMI audio signal, via decoder built-in ZR39660,output data stream of I2S format and S/PDIF data
stream at the same time. Audio data of I2S format is fed to audio D/A conversion chip CS4344 to
output analog L/R signal. S/PDIF data stream directly output from optical fiber interface.

16

Block diagram

AV1 AUDIO

AV2 AUDIO

YPBPR1 AUDIO

YPBPR2 AUDIO

PC AUDIO

SGTV5810

NJW1109

Earphone

Analog SIF

TPA3001D1

Loudspeaker

S_C

D/A CS4345

IIS OUT

CVBS2

S_Y

HEF4052BT

CVBS,Y/C

CVBS1

CVBS_TV

TS

FQD1216/PH5

TUNER

Digital IF

DRX3975D

HS,VS,CLK

24-BIT Data

ZR39660

BGA400

AV_OUT

LVDS

YPBPR1

YPBPR2

TDA8759

FLASH

DDRAM

PC

HDMI

W19B320ABT

2X16MX16

17

Panel

IC block diagram

1. ZR39660

Pin descriptions of ZR39660:
(1) Serial Transport Input Port
T4: MPEG Transport Port Input Clock
T3: MPEG Transport Input Data
U3: MPEG Transport Input Frame
Y1: MPEG Transport Input Valid

(2) HDMI Input
D1,E3,F3,E2,F2,E1: HDMI Differential Data Pairs
D2,C1: HDMI Differential Clock Pair
C3: HDMI Serial Clock

18

B2: HDMI Serial Data
A1: HDMI Hot Plug Detect
D3: HDMI Current Set

(3) NTSC/PAL Analog Input Port
W2:Video Front End Luminance In
Y3:Video Front End Chroma In
W3:Video Front End Common Mode Reference

(4) Analog Video Output
K18:Composite Data Output (CVBS)
J20:Blue/Pb Pixel Data Output
J18:Green/Y Pixel Data Output
J19:Red/Pr Pixel Data Output

(5) Audio I/O
R2:Audio Clock
R3:Bit Clock
P3:Left/Right Channel Selector
U2:Serial Audio Data Input
T2:Serial Audio Data Output
V1:IEC958 Format Out

(6) LVDS Panel Interface
B20,C19: Output Clock Pair
E18,F17: Output Data Pairs 0
C20,D19: Output Data Pairs 1
F18,G17: Output Data Pairs 2
D20,E19: Output Data Pairs 3
E20,F19: Output Data Pairs 4
H18,G18: Output Data Pairs 5
F20,G19: Output Data Pairs 6
G20,H19: Output Data Pairs 7
D18: External Resistor Connection

(7) UART and I2C Interface
N1:UART 0 Transmit
P1 UART 0 Receive
R1:I2C Compatible Clock 0
P2:I2C Compatible Data 0
M3:I2C Compatible Clock 1
M2:I2C Compatible Data 1

(8) Miscellaneous
M4, N3:Two pins required to support the 24.576 MHz crystal

19

N5:Power On Reset
L4:Infrared Receive

2. DRX3975D

The DRX 3975D is a fourth-generation COFDM demodulator that offers today’s highest level of
front-end integration resulting in ultimate DVB-T digital reception, compliant to ETS 300 744, DTG
D-Book,EICTA E-Book, and Nordig Unified v1.0.2 .
The IC applies cutting-edge digital filtering techniques in combination with a high-performance
A/D-converter and PLL configuration, resulting in superior performance figures in the presence of
digital- and analog adjacent channels.

Pin configuration of DRX3975D:

20

Pin description of DRX3975D:
2: RESET_N 56, 57: Oscillator
22: Select I2C address 33: I2C data for host communication with the tuner
34: I2C clock to the tuner 15: I2C clock from host
16: I2C data from/to host 38, 39: Differential input for IF
17, 18, 21,25: Serial Transport Output Port

3. ADC conversion TDA8759

21

Pin configuration of TDA8759:

Pin description:
78,79,80: Red analog input
63,64,65: Green analog input
50,51,52: Blue analog input
72,73,74: Sync on Green analog input
108,109,110: Horizontal SYNC Input
105,106,107: Vertical SYNC Input
29: Hold PLL Frequency, do not track HSYNC
119: Serial Interface clock
118: Serial Interface data pin
96: Serial interface address pin
7-10, 15-18: Red output data
35,36,39-44: Green output data
23-28,31,32: Blue output data
2: Output data clock
167: DE output
168: HSYNC output
169: VSYNC output

22

4. Audio processor SGTV5810

The SGTV58xy is a TV audio processor designed to serve as a low cost, integrated audio
CODEC for hybrid (analog and digital) TVs, digital only TVs, and analog TVs. Other applications
include set top boxes or other media applications where a low cost, high fidelity audio processor is
required. The SGTV58xy has highly integrated features and input/output that simplify TV audio
design.

23

Pin configuration of SGTV5810:

Pin description of SGTV5810:

69-72,57-60,51-54,43-50: Analog AUDIO INPUT L/R

42,39: EAR PHONE L/R

30-35: AV AUDIO OUT L/R

38,37: MAIN AUDIO OUTPUT L/R

93,92: I2C SDA/SCL

95,94: Serial interface address pin

96: RESET_N

83,81:SIF INPUT

87,86: Oscillator

24

5. TPA3001

The sound power amplifier TPA3001 Class D AMP is the high effective D type of power
amplifier of the single track. The BTL output power can reach 20W(10% THD+N) with 8-Ω speakers,
+18V power supply, eliminating the need for heat sinks.

The TPA3001D1 is available in the 24-pin thermally enhanced TSSOP package.

Pin configuration of TPA3001:

Pin descriptions of TPA3001:
1: Negative differential input；
2: Positive differential input；
3, 4: gain control；
10, 11: Negative BTL output；
14, 15: Positive BTL output；
9, 16, 24: Power Supply；
6, 12, 13, 18, 19: Power Ground；
5 : Shutdown terminal；

25

Wiring diagram

Butt on bo ard

RS-232 HDMI VGA

S/PDIF

Digital processing board

`

XA50

31 6 12 11

Logical board

LA03

X802

YpbPr 1 YpbPr2

X602

X601

Powe r boa rd

X603

X608

Panel

X606

5 6 5 5 9

XC01XB01XC02

XB03 X801 X603

X232X103X102

X231 X101 X226

5

4 6

X501

AV out Earp hone S-Vide o AV1 in AV2 in

X105

2

Analog board

X106

Speaker assy

Power filter board

X104

4

RF

26

Trouble shooting

Before servicing please check to find the possible causes of the troubles according to the table
below.

1.Antenna(signal):

Picture is out of focus or jumping 6. Bad status in signal receiving

7. Poor signal

8. Check if there are failures with the electrical connector or
the antenna.

9. Check if the antenna is properly connected.

Fringe in picture z Check if the antenna is correctly oriented.

z Maybe there is electric wave reflected from hilltop or

building.

Picture is interfered by stripe
shaped bright spots

There appear streaks or light color
on the screen

2.TV set:

Symptoms Possible cause

Unable to switch the power on z Check to see if the power plug has been inserted

No picture and sound z Check to see if the power supply of liquid crystal TV has

Deterioration of color phase or
color tone

Screen position or size is not

proper

Picture is twisted and deformed z Check to see if the picture-frame ratio is properly set up.

Picture color changed or colorless z Check the “Component” or “RGB” settings of the liquid

z Possibly due to interference from automobile, train, high

voltage transmission line, neon lamp etc.

z Maybe there is interference between antenna and power

supply line. Please try to separate them in a longer
distance.

z Maybe the shielded-layer of signal wire is not connected

properly to the connector.

z Check if interfered by other equipment and if interfered

possibly by the equipment like transmitting antenna, non
professional radio station and cellular phone.

properly into the socket.

been switched on. ( as can be indicated by the red LED
at the front of the TV set)

z See if it’s receiving the signal that is transmitted from

other source than the station

z Check if it’s connected to the wrong terminal or if the

input mode is correct.

z Check if the signal cable connection between video

frequency source and the liquid crystal TV set is correct.

z Check if all the picture setups have been corrected.

z Check is the screen position and size is correctly set up.

crystal TV set and make proper adjustment according to

27

Symptoms Possible cause

the signal types.

Picture too bright and there is
distortion in the brightest area

z Check if the contrast setting is too high.
z Possibly the output quality of DVD broadcaster is set too

high.

z It maybe also due to improper terminal connection of the

video frequency signal in a certain position of the
system.

Picture is whitish or too bright in
the darkest area of the picture

z Check if the setting for the brightness is too high
z Possibly the brightness grade of DVD player

(broadcaster) is set too high.

No picture or signal produced from
the displayer if “XXX in search”
appears.

There appears an indication ­“outside the receivable scope)

z Check if the cable is disconnected.
z Check if it’s connected to the proper terminal or if the

input mode is correct.

z Check if the TV set can receive input signal. The signal is

not correctly identified and VGA format is beyond the
specified scope.

Remote control cannot work
properly

z Check if the batteries are installed in the reverse order.
z Check if the battery is effective.
z Check the distance or angle from the monitor.
z Check if there is any obstruct between the remote control

and the TV set.

z Check if the remote control signal- receiving window is

exposed to strong fluorescence.

No picture and sound, but only

hash.

z Check if the antenna cable is correctly connected, or if it

has received the video signal correctly.

Blur picture z Check if the antenna cable is correctly connected.

z Of if it has received the right video signal.

No sound z Check if the “mute” audio frequency setting is selected.

z Check if the sound volume is set to minimum.
z Make sure the earphone is not connected.
z Check if the cable connection is loose.

When playing VHS picture search
tape, there are lines at the top or
bottom of the picture.

10. When being played or in pause VHS picture search tape
sometimes can’t provide stable picture, which may lead
to incorrect display of the liquid crystal TV, In this case
please press “auto” key on the remote control so as to
enable the liquid crystal TV set to recheck the signal and
then to display correct picture signal

28

Troubleshooting guide

Yes, turn the unit on

If the picture of each channel

is normal?

If the sound of each channel is

normal?

(1) abnormal picture

a) A certain differential wire pair of LVDS of XA50 (RX0+/-, RX1+/-, RX2+/-, RX3+/-)is

b) Failure with resistor rows RA18~RA25, which may lead to loss of corresponding color

c) Failure with NA50 and its periphery components, which may lead to picture abnormal of

d) Failure with N103, which may lead to picture abnormal of TV, AV1, AV2, S-VIDEO.

Begin

A red indicator

lights?

A blue indicator

lights?

Ye s

Display picture?

Ye s

abnormal, which may lead to lack of color or color splash.

from the gray degree corresponding to the picture of channel HDMI.

PC, YPrPb and YCrCb.

No

No

No

No

No

Check power board , button board and power

cord

Check if the pin1 of X602 in data processing

board is high level(+5V)? check V660/V661.

Check if the crystal in data processing board

starts, DDR clock is correct?

Check the signal inputted from the channel to

pin IC or IC and its peripheral circuit or the

output of LVDS is normal

Check the signal inputted from the channel to

pin IC is normal or IC(SGTV5810/TPA3001)

and its periphery is normal

29

(2) no picture, no sound

g

b

p

p

p

p

Red

Check the power

oard

No sound No picture

Refer to (3) checking

rocedure

(3) with picture but no sound

With picture but no sound

Check if the voltage of sound amplifier

of X113 in analog board is normal?

Check if the pin2 of N112/N113

in

Ye s

Check N112/N113 and

their peripheral circuit

No picture, no sound

Check the color of indicator

li

ht

Ye s

Refer to (4) checking

rocedure

Ye s

uts signals

No

Check N106 and its

eripheral circuit

Blue

Check the output voltage of

sockets X603/X606/X608

No

Power board problem

No

Check the power board

30

(4) with sound but no picture

If there is no picture

in all channels?

Ye s

Check N108 and

its peripheral circuit

With sound but no picture

Display OSD MENU?

Ye s

Display LOGO? If pin5 of X602 (IRR) has signal?

Yes N o

Check if the crystal in data processing board starts,

DDR clock and DDR SDRAM are normal?

No

Refer to (5), (6), (7), (8), (9),

(10), (11) checking procedure

No

31

(5) AV no picture

Check if pin13 of N103

outputs signals?

Ye s

Check the periphery circuit

from XC02 to N801

(6) S-terminal no picture

Check if pin13/3 of N103

outputs signals?

Ye s

Check the periphery circuit

from XC02 to N801

Check if C155 and C156

input signals?

Ye s

No

Check if C123 and C157

input signals?

Ye s

No

No

Check N104/N107 and the circuit

from AV terminal to N103

Check N103 and its

periphery circuit

No

Check N108 and the circuit

from S-terminal to N103

Check N103 and its

periphery circuit

32

(7) TV channel no picture

Check if pin12 of TUNER241

output signals?

Ye s

No

Check if pin13 of N103

outputs signals?

Check TUNER241 power supply

and the peripheral circuit.

Ye s

No

Check the periphery circuit

from XC02 to N801

Check N103 and its

periphery circuit

(8) DVB-T channel no picture

Check if pin7/8 of TUNER241

output signals?

Ye s

No

Check if the crystal of

N242 (4MHz) is normal?

Check TUNER241 power supply

and the peripheral circuit.

Ye s

No

Check the clock signal of

the front 4 pins of XC01

Check G241, N242 and

periphery circuit

Note :

The I2C bus line control of TUNER is switch through the bus line of N242, so after checking the
power supply and peripheral circuit of TUNER241, it is still no picture in TV and DVB-T channel,
please check N242 emphatically.

33

(9) YPrPb or YCrCb channel no picture

Check if pin63/64/72/73 of

NA05 output signals?

Ye s

Check if resistor rows RS72~RA74,

RA77~RA79 are well jointing

Ye s

Check NA50 and its periphery

(10) D-sub channel no picture

Check if pin52/65/80 of NA50

and pin105/108 output signals?

Ye s

Check if resistor rows RA72~RA74,

RA77~RA79 are well jointing

Ye s

Check NA50 and peripheral

circuit.

No

Check the path from NB01,

NB02, NA50 to YPbPr

No

Check NB03/NB04 and the circuit

from NA50 to VGA socket

34

(11) HDMI channel no picture

p

Check DETECT NA04 and its

peripheral circuit?

Ye s

No

Check if signals of

RA18~RA25 are normal?

Ye s

Check N801 and its

eripheral circuit

Check the connection to HDMI

socket, NA04 and its peripheral

circuit

Note: N801 embeds FLASH, which stores HDCP information of HDMI, while EDID data stored in
external EEPROM(NA02), so make sure the connection between HDMI socket/interface and the
data of NA02 is well flash write, the picture and sound will display normally.

35

Block diagram of 42” power board

AC IN

EMI

Rectify

STR

–E1565

PFC

Isol ation

18V

AP1501

AP1501

AP1501

AP1501A

Fliter

3V3SC

5VSC

5VCTRL

12VSC

18VSC

5VSB

Va

Vs

STR A6159M

–

Isolation

STR F6468–

Isolation

STR X6769–

DC/DC

Isolation

DC/DC

DC/DC

DC/DC

DC/DC

DC/DC

DC/DC

DC/DC

MCU

ATMEGA8L

IIC

IR

KEY

VGA_H∕V

LED

RESET

5VCTRL Va.Vs.

Overvolta ge underv oltg ae tes t.

Input AC volt age te st

Output volt age co ntro l ON/O FF

Va,Vs activ e disc hage c ontr ol

PFC OUT 400V

36

Troubleshooting of 42” power board

Instruction of system and time sequence control

The whole system is composed of EMI, rectify, PFC, DC/DC and MCU. Therein MCU is the control
core of the whole system. On the one hand, it controls ON/OFF time sequence of each voltage and
the main AC voltage test. On the other hand, it performs the standby CPU function with IIC bus to
the main CPU.

Time sequence

The system has two working modes: AUTO and NORMAL, AUTO mode is used for adjustment and
service, while NORMAL mode is used for TV at normal time. At AUTO mode(short X610), connect
5VCTRL with load of about 2A, turn on power, then output several low-voltage power supplies,
delay 1.5s or so and output Va, Vs. First stop the output of Va, Vs at power-down, and active
discharge to output-capacitor of Va,Vs. on condition that the voltage Va,Vs each is lower than 10
percent (if unsatisfied, then wait), then delay 0.5s and stop all the low-voltage power supplies
except for 5VSB into Standby mode.
At NORMAL mode, MCU receives power-on control of IR or button board, outputs several
low-voltage power supplies, after main CPU sending Va,Vs start-control through IIC bus, outputs
Va,Vs. at the status of turn on, MCU receives power-down control from main CPU and performs
power-down time sequence (power-down time sequence is the same at AUTO mode).
At the two modes, when detect the lower input AC voltage, it will not perform power-on. At the status
of turn on, when detect the lower input AC voltage or 5VCTRL,Va,Vs beyond normal scope value, it
will perform the power-down time sequence above and enter into Standby mode.

Trouble diagnosis

The voltage 5VSB is normal, while the voltages of other circuits are zero, in this case, it may switch
power on at AUTO mode and check if 5VCTRL delay 1.5s or so, if NO, check 5VCTRL and its
fore-circuit; if YES, check LED (LED601), if LED lights, check the circuit of Va, jf not, check the
circuit of Vs (note: premise N608 and its periphery circuit are normal). If the voltages of other circuits
are abnormal, check the corresponding circuits.

Trouble phenomenon (premise the voltage 5VSB is normal)
The main voltage of power board is abnormal, which is commonly detected to enter into Standby
mode, the phenomenon is that switch power off immediately after switching power on.
AC detect circuit or IR, button circuit is abnormal, which will lead to unable to switch power on.
The low-voltage power supplies are normal, while the voltage Va, Vs is zero, it maybe
communication abnormal of IIC bus between MCU and main CPU.

37

APPENDIX-A: Main assembly

Model Part name No.

PH-42FB31 Digital processing board 667.PHIFB31-69

Key board 667.PHIFC31-05

IR receiver board 667.PHIFC31-09

Power board 667.PH42FB6-20

Power filter board 667.PH42T8-51

Analog board 667.PS42FB6-53

Remote control 301.D42FB6-06

Panel 335.42014-00

PH-50FB31 Digital processing board 667.PHIFB31-69

Key board 667.PHIFC31-05

IR receiver board 667.PHIFC31-09

Power board 667.PHST18-20

Power filter board 667.50FB18-51

Analog board 667.50FB18-53

Remote control 301.D42FB6-06

Panel 335.50005-00

603-PH42FB31-12

Ver.1.0