Xoceco LC-52R36 Schematic

LCD TELEVISION

LC-52R36

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

1. Instructions

Be sure to switch off the power supply before replacing or welding any components or
inserting/plugging in connection wire Anti static measures to be taken (throughout the entire
production process!):
a) Do not touch here and there by hand at will;
b) Be sure to use anti static electric iron;
c) It’s a must for the welder to wear anti static gloves.
Please refer to the detailed list before replacing components that have special safety requirements.
Do not change the specs and type at will.

2. Points for attention in servicing of LCD

2.1 Screens are different from one model to another and therefore not interchangeable. Be sure to
use the screen of the original model for replacement.

2.2 The operation voltage of LCD screen is 700-825V. Be sure to take proper measures in
protecting yourself and the machine when testing the system in the course of normal operation or
right after the power is switched off. Please do not touch the circuit or the metal part of the module
that is in operation mode. Relevant operation is possible only one minute after the power is
switched off.

2.3 Do not use any adapter that is not identical with the TV set. Otherwise it will cause fire or
damage to the set.

2.4 Never operate the set or do any installation work in bad environment such as wet bathroom,
laundry, kitchen, or nearby fire source, heating equipment and devices or exposure to sunlight etc.
Otherwise bad effect will result.

2.5 If any foreign substance such as water, liquid, metal slices or other matters happens to fall into
the module, be sure to cut the power off immediately and do not move anything on the module lest it
should cause fire or electric shock due to contact with the high voltage or short circuit.

2.6 Should there be smoke, abnormal smell or sound from the module, please shut the power off at
once. Likewise, if the screen is not working after the power is on or in the course of operation, the
power must be cut off immediately and no more operation is allowed under the same condition.

2.7 Do not pull out or plug in the connection wire when the module is in operation or just after the
power is off because in this case relatively high voltage still remains in the capacitor of the driving
circuit. Please wait at least one minute before the pulling out or plugging in the connection wire.

2.8 When operating or installing LCD please don’t subject the LCD components to bending, twisting
or extrusion, collision lest mishap should result.

2.9 As most of the circuitry in LCD TV set is composed of CMOS integrated circuits, it’s necessary
to pay attention to anti statics. Before servicing LCD TV make sure to take anti static measure and
ensure full grounding for all the parts that have to be grounded.

2.10 There are lots of connection wires between parts behind the LCD screen. When servicing or
moving the set please take care not to touch or scratch them. Once they are damaged the screen

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would be unable to work and no way to get it repaired.
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.

2.11 Special care must be taken in transporting or handling it. Exquisite shock vibration may lead to
breakage of screen glass or damage to driving circuit. Therefore it must be packed in a strong case
before the transportation or handling.

2.12 For the storage make sure to put it in a place where the environment can be controlled so as to
prevent the temperature and humidity from exceeding the limits as specified in the manual. For
prolonged storage, it is necessary to house it in an anti-moisture bag and put them altogether in one
place. The ambient conditions are tabulated as follows:

Temperature Scope for operation 0 ~ +50 oC

Scope for storage -20 ~ +60 oC

Humidity Scope for operation 20% ~ 85%

Scope for storage 10% ~ 90%

2.13 Display of a fixed picture for a long time may result in appearance of picture residue on the
screen, as commonly called “ghost shadow”. The extent of the residual picture varies with the
maker of LCD screen. This phenomenon doesn’t represent failure. This “ghost shadow” may remain
in the picture for a period of time (several minutes). But when operating it please avoid displaying
still picture in high brightness for a long time.

3. Points for attention during installation

3.1 The front panel of LCD screen is of glass. When installing it please make sure to put it in place.

3.2 For service or installation it’s necessary to use specified screw lest it should damage the screen.

3.3 Be sure to take anti dust measures. Any foreign substance that happens to fall down between
the screen and the glass will affect the receiving and viewing effect

3.4 When dismantling or mounting the protective partition plate that is used for anti vibration and
insulation please take care to keep it in intactness so as to avoid hidden trouble.

3.5 Be sure to protect the cabinet from damage or scratch during service, dismantling or mounting.

Alignment instructions

1. Test equipment

PM5518 (Video signal generator)
VG-848 (Signal generator)
CA210 (White balancer)

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2. The alignment flow chart (see below figure)

Production of main board and analog board on the line.

Check DDC, HDCP KEY and FLASH

Check CPU board and analog board

Combined test for general assembly

Connect to central signal source; check if various

TV functions (station skipping, modulate quantity

control etc), check if the output of earphone and

speaker are normal.

Input AV/S signal and HDTV signal; check various

functions under AV/S terminal

Input VGA signal and check if display is normal in

the state of PC and various functions (analog

quantity control, line/field center etc.)

Input HDMI signal and check if display is normal in

the state of HDMI and various functions (sound

and analog quantity control).

Preset ex-factory

Check accessories and then packing

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3. Adjustment illustration

3.1 The unit adjustment

Connect all the boards according the wiring diagram, then power on and check the display.

3.2 The method for entering factory menu

Enter factory menu method: press the SOURCE→ 2→ 5→8→0 buttons one by one on the remote
control to enter factory menu. When the first line of the adjustment item is light, press the MENU
button to select item and press the DSP button to exit the factory menu.

3.3 EEPROM initialization

Enter the firs page of factory menu, adjust item OPTION-1 to 25, OPTION-2 to 5, select the
EEPROM Initial after, press the VOL+ button, then display the DOING, still the DOING disappear
and turn off the unit.
Note: option-1 and option-2 function as follows:

Option-1 Option-2

Bit4 0: RS232 can’t be controlled by the external unit

1: RS232 can be controlled by the external unit

Bit3 0: No memory function after power off for 10s

1: memory function after power off for 10s

Bit2,1 00: STANDBY

01: turn on

10: memory function of turn on

Bit0 0: without LOGO

1: With LOGO

0: Gammar On

1: Gammar Off

0:no signal noise wave of TV

1:no signal blue screen of TV

hold

0: Video and Graphic channel white balance no share

1: Video and Graphic channel white balance share

3.2 HDMI channel adjustment

Input the VG-848 TIME854(800X600/60Hz) and PATTERN920 8-LEVEL gray signal, enter the
factory menu2(white balance adjustment menu), adjust the third step and the seventh step.
Adjust R-offset, G-offset and B-offset item, still the third step color coordinate to (275, 285). Adjust
R-gain, G-gain and B-gain item, still the seventh step color coordinate to (275, 285). Repeat
adjustment R-offset, G- offset and B- offset item and R-gain, G-gain and B-gain item, still two step
gray to (275, 285).
Note: R-offset, G-offset, B-offset values must be an item value to 128 at least; R-gain, G-gain,
B-gain values must be an item value to 255 at least.

3.3 VGA channel adjustment

3.3.1 mode pre-set
Input the VGA signal of VG-848 (PATTERN 980:1 dot ON/OFF), select the TIME877 (720x400/70Hz)
signal, press auto-adjust button to all screen or adjust PC settings menu to auto correction.
Separate auto adjust for TIME885 (640x480/60Hz) and TIME854 (800x600/60Hz).

3.3.2 VGA channel auto color adjustment
Input the VG-848 TIME854(800x600/60Hz) and PATTERN920(GRAY 8 STEP(H)), enter the factory
menu1, select the AUTO COLOR after, press the VOL+ button to select AUTO COLOR.

3.4 YPBPR channel adjustment

Input the VG-848 TIME972(1080i/60Hz) and PATTERN976(64 GRAY & Color), enter the factory
menu1, select the AUTO COLOR after, press the VOL+ button to select AUTO COLOR.

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4. Performance check

4.1 TV function
Input center source signal to RF-TV terminal, enter search menu→auto search, check if the channel
is leak for auto searching.

4.2 AV/S and YPbPr terminal
Input AV/S and HDTV signal, check if the signal is normal.

4.3 VGA terminal
Input 640 x 480 @60Hz VGA format signal, check if the signal is normal.

4.4 HDMI terminal
Separate input HDMI and DVI signal; check the picture and sound is normal, check if the HDCP
function is normal.

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

4.6 check the clock
Enter user’s clock setting menu, set the clock and calendar and power off, then power on and check
if the clock and calendar settings are stored.

4.7 light sensor function
Enter user’s picture menu, set “light sensor” to On and check if the brightness of picture changes
according to the ambient room light conditions

4.6 ex-factory setting
Enter the first page of factory menu, select the factory out after, press the VOL+ button to display
“doing”, then “doing” disappear while it can auto ex-factory setting.

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Working principle analysis of the unit

The RF1 via integrative tuner TUNER1 after, the FBAS VIDEO1 and SIF is generated. The RF2 via
integrative tuner TUNER2 after, the FBAS VIDEO2 and AUDIO is generated. Video signal and
audio signal of VIDEO1,VIDEO2,AV1/SVHS1,AV2,AV3 and audio signal of VGA and so on, its sent
NA3 (CXA2089Q) to switch selection. The output video signal of main picture (Y/V, C) sent N7
(TVP5160) to decode. The signal via N7 decode after, it sent 8-bit ITU-R656 format signal to N10
(FLI2310) non-interlaced processing. It sent 24bit YUV signal to main processing control chip
N15(GM1501/1601).
The sub-picture video signal via CXA2089Q select after, it sent N8 (TVP5147) to decode. The signal
via N8 decode after, it sent 8-bit ITU-R656 format signal to N15 (GM1501/1601). Therein, the signal
of TUNER2 is sub-picture only.
The main-picture video signal from CXA2089Q is sent to decoder and also AV OUTPUT.
USB signal via A/V decoder AML278 to output RGB and digital audio signal, the audio signal via
CS4334 D/A convert then output L/R-USB.
Two ways YPBPR signal via HDTV switch NA1(PI5V330W) selection after, it sent to HDTV switch
device NA15(PI5V330W) switch selection together with USB signal, then sent RGB switch
N4(PI5V330W) select with RGB from VGA port of PC , then it sent to GM1501/1601.
Another two ways HDMI via HDMI switch (FSHDMI04) selecting after, it sent to HDMI receiver
N34(MST3383MB), then output RGB signal of 24bit to GM1501/1601.
They sent to GM1501/1601 picture processing, therein YPBYP or RGB to A/D conversion after, it
and other two signals are switched selection and digital display processing, it include OSD, GAMMA
correction, brightness and contrast processing, then LVDS conversion to signal acceptable for LCD
panel, namely four pairs of differential signal and one pair of clock signal, then it is sent to image
enhancer PW9702 to improve the image, and then to LCD panel for picture display.
The SIF of tuner output signal to audio processing NA4(MSP3420),The audio of main-picture and
sub-picture via switch conversion CXA2089Q to MSP3410; the audio of two YPBPR and USB
processed by AML3278 via switch conversion NA2(HEF4052) to MSP3410, the HDMI via
MST3383MB decode to audio, it audio via N26(CS4334) D/A conversion to MSP3410 too.
The stereo of the SIF with other four ways audio switch conversion selection to volume control and
audio processing. One way output right/left channel audio of main-picture, the signal sent SRS
processing NA5 (M62494) to SRS sound stereo processing. It via sound amplifier NA20, NA21
(TPA3001D1) to speaker; one way output right/left channel audio of sub-picture, it sent to earphone,
another way is AV OUT R/L output.
The work of whole unit is controlled by MCU, which includes GM1501/1601.

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Black diagram

Hs,Vs

RGB

VGA

YPbPr1
YPbPr2

USB

A/V Processor
AML3278

HDMI1
HDMI2

EDID
24C02

EDID
24C02

L/R-HDMI

Y Main/C Main V-PIP

AV1
AV2 L/R-PIP
AV3
L/R-VGA L/R-Main
Tuner2
V-AVOUT SIF
Tuner1
L/R-HDMI
L/R-YPbPr1
L/R-YPbPr2
L/R-USB
L/R-AVOUT

VIDEO DEC.
TVP5160

EDID
24C02

HDTV SW.
PI5V330

HDMI SW.
FSHDMI04

LOGIC SW.
CBT3257

AV SW.
CXA2089Q

AUDIO SW.
HEF4052

HDTV SW.
PI5V330

D/A
CS4334

HDMI RX
MST3383

D/A
CS4334

DEINTERLACER
FLI2310

VIDEO DEC.
TVP5147

AUDIO

PROCESSOR

MSP3410/MSP3420

SN74AHC14

RGB SW.
PI5V330

L/R-USB

HDCP KEY
24C04

Power-ON,IR,KeyA,
KeyB,Led1,Led2,Mute,
HP-SW,VGA-CAB,DV
I-CAB,YUV/VGA,YU
V-SW,YUV/USB

LCD TV
CONTROLLER

GM1501/GM1601

SRS
M62494

HP AMP
TDA7053

DDR

FLASH

EEPROM

IMAGE QUALITY
ENHANCER
PW9702

PANEL

SPEAKER

AUDIO AMP .
TPA3001 x2

HEAD
PHONE

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IC block diagram

1.MSP34X0G

The MSP 34x0G family of single-chip Multistandard Sound Processors covers the sound
processing of all analog TV-Standards worldwide, as well as the NICAM digital sound standards.
The full TV sound processing, starting with analog sound IF signal-in, down to processed analog
AF-out, is performed on a single chip. Figure 1–1 shows a simplified functional block diagram of the
MSP 34x0G.
This new generation of TV sound processing ICs now includes versions for processing the
multichannel television sound (MTS) signal conforming to the standard recommended by the
Broadcast Television Systems Committee (BTSC). The DBX noise reduction, or alternatively,
Micronas Noise Reduction (MNR) is performed alignment free.
Other processed standards are the Japanese FM-FM multiplex standard (EIA-J) and the FM Stereo
Radio standard.
Current ICs have to perform adjustment procedures in order to achieve good stereo separation for
BTSC and EIA-J. The MSP 34x0G has optimum stereo performance without any adjustments.
All MSP 34xxG versions are pin compatible to the MSP 34xxD. Only minor modifications are
necessary to adapt a MSP34xxD controlling software to the MSP 34xxG. The MSP 34x0G further
simplifies controlling software. Standard selection requires a single I2C transmission only.
The MSP 34x0G has built-in automatic functions: The IC is able to detect the actual sound standard
automatically (Automatic Standard Detection). Furthermore, pilot levels and identification signals
can be evaluated internally with subsequent switching between mono/ stereo/bilingual; no I2C
interaction is necessary (Automatic Sound Selection).
The MSP 34x0G can handle very high FM deviations even in conjunction with NICAM processing.
This is especially important for the introduction of NICAM in China.
The ICs are produced in submicron CMOS technology. The MSP 34x0G is available in the following
packages: PLCC68 (not intended for new design), PSDIP64, PSDIP52, PQFP80, and PLQFP64.

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Fig. 1–1: Simplified functional block diagram of the MSP 34x0G

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2. TVP5160

The TVP5160 device is a high quality; digital video decoder that digitizes and decodes all popular
baseband analog video formats into digital component video. The TVP5160 decoder supports the
A/D conversion of component YPbPr and RGB (SCART) signals, as well as the A/D conversion and
decoding of NTSC, PAL, and SECAM composite and S-Video into component YCbCr. Additionally,
component progressive signals can be digitized. The chip includes two 11-bit, 60-MSPS, A/D
converters (ADCs). Prior to each ADC, each analog channel contains an analog circuit, which
clamps the input to a reference voltage and applies a programmable gain and offset. A total of 12
video input terminals can be configured to a combination of YPbPr, RGB, CVBS,
and S-Video video inputs. Progressive component signals are sampled at 2x clock frequency (54
MHz) and are then decimated to the 1x rate. In SCART mode the component inputs and the CVBS
inputs are sampled at 54 MHz alternately, then decimated to the 1x rate. Composite or S-Video
signals are sampled at 4x the ITU-R BT.601 clock frequency (54 MHz), line-locked for correct pixel
alignment, and are then decimated to the 1x rate. CVBS decoding utilizes advanced 3D Y/C filtering
and 2-dimensional complementary 5-line adaptive comb filtering for both the luma and chroma data
paths to reduce both cross-luma and cross-chroma artifacts. 3D Y/C color separation may be used
on both PAL and NTSC video signals. A chroma trap filter is also available. On CVBS and Y/C
inputs, the user can control video characteristics such as hue, contrast, brightness, and saturation
via an I2C host port interface. Furthermore, luma peaking with programmable gain is included, as
well as a patented color transient improvement (CTI) circuit. Attenuation at higher frequencies or
asymmetrical color subcarrier sidebands are compensated using the IF compensation block. Frame
adaptive noise reduction may be applied to reduce temporal noise on CVBS, S-Video, or
component inputs. 3D noise reduction and 3D Y/C separation may be used at the same time or
independently. The TVP5160 decoder utilizes Texas Instruments’ patented technology for locking
to weak, noisy, or unstable signals and can auto-detect between broadcast quality and VCR-style
(nonstandard) video sources. The TVP5160 decoder generates synchronization, blanking, field,
active video window, horizontal and vertical syncs, clock, genlock (for downstream video encoder
synchronization), host CPU interrupt and programmable logic I/O signals, in addition to digital video
outputs. The TVP5160 decoder includes methods for advanced vertical blanking interval (VBI) data
retrieval. The VBI data processor (VDP) slices and performs error checking on teletext, closed
caption, and other VBI data. A built-in FIFO stores up to 11 lines of teletext data, and, with proper
host port synchronization, full-screen teletext retrieval is possible. The TVP5160 decoder can pass
through the output formatter 2x sampled raw Luma data for host-based VBI processing. Digital RGB
overlay can be synchronously switched with any video input, with all signals being oversampled at
4x the pixel rate.

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INTERNAL BLOCK DIAGRAM:

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3. TPA3001D1

The TPA3001D1 is a 20-W mono bridge-tied load (BTL) class-D audio power amplifier with high
efficiency, eliminating the need for heat sinks. The TPA3001D1 can drive 4-Ω or 8-Ω speakers with
only a ferrite bead filter required to reduce EMI.
The gain of the amplifier is controlled by two input terminals,GAIN1 and GAIN0. This allows the
amplifier to be configured for a gain of 12, 18, 23.6, and 36 dB. The differential input stage provides
high common mode rejection and improved power supply rejection.
The amplifier also includes depop circuitry to reduce the amount of pop at power-up and when
cycling SHUTDOWN.
The TPA3001D1 is available in the 24-pin thermally enhanced TSSOP package (PWP) which
eliminates the need for an external heat sink.

INTERNAL BLOCK DIAGRAM:

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