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Service Manual
(1906 2206)
HDMI

MST719

2009/10/13

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Contents

1. Precautions and Safety Notices..................................................................3 2. Specification.............................................................................................5 3. Function Control Description......................................................................10 4. Circuit Description....................................................................................11 5. Adjusting Procedure.................................................................................17 6. Trouble Shooting Flow Chart.............................................................................23 7. Block Diagrams........................................................................................26

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1. Precautions and Safety Notices
Prior to using this service manual, please ensure that you have carefully followed all the procedures outlined in the user's manual for this product. (1) Read all of these instructions. (2) Save these instructions. (3) Follow all warnings and instructions a marked on the product. (4) Unplug this product from the wall outlet before cleaning. Do not use liquid cleaners or aerosol cleaners, use a damp cloth for cleaning. (5) Do not use this product near water. (6) Do not place this product on an unstable cart, stand or table. The product may fall, causing serious damage to the product. (7) Slots and openings in the cabinet and the back or bottom are provided for ventilation, to ensure reliable operation of the product and to protect it from overheating, those openings must not be blocked or covered. The openings should never be blocked by placing the product on a bed, sofa, rug, or other similar surface. This product should not be placed in a built-in installation less proper ventilation is provided. (8) These products should be operated from the type of power source indicated on the marketing label. If you are not sure of the type of power available, consult your dealer or local power company. (9) This product is equipped with a 3-wire grounding type plug, a plug having a third (grounding) pin. This plug will only fit into a grounding-type power outlet. This is a safety feature, if you are unable to insert the plug into the outlet, contact your electrician to replace your obsolete outlet. Do not defeat the purpose of the grounding-type plug. (10) Do not allow anything to rest on the power cord. Do not locate this product where persons will walk on the cord. (11) If an extension cord is used with this product, make sure that the total of the ampere ratings on the product plugged into the extension cord to the waplugged into outlet does not exceed 15 ampere. (12) Never push objects of any kind into this product through cabinet slots as they may touch dangerous voltage points or short out parts that could result in a risk of fire or electric shock. Never spill liquid of any kind on the product. (13) Do not attempt to service this product yourself, as opening or removing covers may expose you to dangerous voltage points or other risks. Refer all servicing to service personnel. (14) Unplug this product from the wall outlet and refer servicing to qualified service personnel under the following conditions: a. When the power cord or plug is damaged or frayed. b. If liquid has been spilled into the product.
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c. If the product has been exposed to rain or water. d. If the product does not operate normally, when the operating instructions are followed. Adjust only those controls that are covered by the operating instructions since improper adjustment of other controls may result in damage and will often require extension work by a qualified technician to restore the product to normal operation. e. If the product has been dropped or the cabinet has been damaged. f. If the product exhibits a distinct change in performance, indicating a need for service.

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2.Specification
Model No. Display Pixel Pixel Pitch Active Display Area Pixel Type Number of Colors View Angle Brightness Contrast Ratio Brightness Uniformity Power Source Power Consumption Sound Output 19" 1440 (H) x 900(V) 0.285mm (H) x0.285mm (V) 410.4 (H) x 256.5 (V) R+G+B vertical stripe 16.2M ±85°degree(H), ±80°degree (V) Typical 300cd/m2 typical 850:1 typical at CR 10 75% min. 100-240V~,50/60Hz,50W 42W Max with speaker Standby: 1.5W 3W ×2 8 22" 1680 (H) x 1050(V) 0.282mm (H) x0.282mm (V) 473.76 (H) x 296.1(V) R+G+B vertical stripe 16.7M ±85°degree(H), ±80°degree (V) Typical 300cd/m2 typical 700:1 typical at CR 10 75% min. 100-240V~,50/60Hz,50W 50W Max with speaker Standby: 1.5W 3W ×2 8

AV/TV Source

Inputs &

Signals

Video Format

Connector types Video Sound None RCA x 2 RCA x 2 Earphone

Outputs ANT Main-TV PH Type PAL/SECAM VIDEO Video + L/R Audio CVBS RCA x 1 S-VIDEO S-VIDEO+ L/R Audio Y/C Mini Din 4 Pin VGA VGA+ L/R Earphone Analog RGB VGA15 Pin HDMI HDMI Digital RGB 19 Pin SCART CVBS/RGB ,Video IN/OUT, PAL,NTSC,SECA SCART M connector Audio IN/OUT

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Graphic and Video signal Output Source Speaker Out The Speaker Out Output Jack Shall Consist of 1. 3.5mm Mini-stereo ×1 Analog HD15 PC Signal (RGB) Format Level/Impedance DDC 1/2B Sync Frequency Maximum Pixel Clock Connector Format Level / Impedance S-Video (Y/C) Signal Formal Level / Impedance Y, C Y: 1.0Vp-p / 75 C: ±286mV / 75 RGB PC Timing STANDARD VESA VESA VGA SVGA SVGA XGA SXGA STANDARD NTSC PAL STANDARD SDTV 576i
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R, G, B Analog 0.7Vp-p / 75 Compliant with Revision 1.3 H/V separate 3V TTL level / 1k Fh3180kHz Fv5676Hz 135MHz Mini VGA 15pin (female) ×1 Video (Composite) CVBS Signal PAL,NTSC,SECAM 1.0Vp-p / 75

RESOLUTION 640×400 720×400 640×480 800×600 800×600 1024×768 1280×1024 RESOLUTION 525 625 STANDARD SDTV 576i

V FREQ Hz 85.081 85.081 59.941 56.250 60.317 60.004 60.020 V FREQ Hz 60 50 STANDARD SDTV 576i

H FREQ Hz 37.861 37.861 31.469 35.156 37.879 48.363 63.981 H FREQ KHz 15.734 15.625 STANDARD SDTV 576i

CLK MHz 31.500 35.500 25.175 36.000 40.000 65.000 108.000 CLK MHz 12.65 14.50 STANDARD SDTV 576i
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Video & S-Video AV Timing

HDTV/Component AV Timing

SDTV 576p SDTV 480i SDTV 480p HDTV 720p HDTV 720p HDTV 1080i

SDTV 576p SDTV 480i SDTV 480p HDTV 720p HDTV 720p HDTV 1080i

SDTV 576p SDTV 480i SDTV 480p HDTV 720p HDTV 720p HDTV 1080i

SDTV 576p SDTV 480i SDTV 480p HDTV 720p HDTV 720p HDTV 1080i

SDTV 576p SDTV 480i SDTV 480p HDTV 720p HDTV 720p HDTV 1080i

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Signal Connector Pin Assignment HMDI connector is a type A receptacle for video/audio mode.

1.TMDS Data 2+ 2.TMDS Data 2 shield 3.TMDS Data 24.TMDS Data 1+ 5.TMDS Data 1 shield 6.TMDS Data 17.TMDS Data 0+ 8.TMDS Data 0 shield

9.TMDS Data 010.Clock + 11.Clock shield 12.Clock 13.CEC 14.NC 15.DDC CLK 16.DDC Data

17.CEC/GND 18.+5V Power 19.Hot Plug Detect

VGA connector VGA connector pin assignment 1.Red 2.Green 3.Blue 4.ISP SCL 5.GND 6.GND 7.GND 8.GND 9.+5V 10. GND 11.ISP SDA 12.VGA SDA 13.H-sync. 14.V-sync. 15.VGA SCL

Mini DIN CNC 4 Pins (SCN570S3NS00000) for S-video, the pin assignment is described as below:

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SCART connector

Pin No. Signal Inter Connection Pin No. 1 Audio right channel output (0.5 Vrms, < 1K ohms) 2 2 Audio right channel input (0.5 Vrms, > 10K ohms) 1 3 Audio left channel output (0.5 Vrms, < 1K ohms) 6 4 Audio ground 4 5 Blue signal ground 5 6 Audio left channel input (0.5 Vrms, > 10K ohms) 3 7 Blue signal I/O (0.7 Vp-p, 75 ohms) 7 8 Function switching I/O (L: < 2V, H: > 10V, 10K ohms) 8 9 Green signal ground 9 10 Intercommunication data line No. 1 10 11 Green signal I/O (0.7 Vp-p, 75 ohms) 11 12 Intercommunication data line No. 2 12 13 Red signal ground 13 14 Blanking signal ground 14 15 Red signal I/O (0.7 Vp-p, 75 ohms) 15 16 Blanking signal I/O (L: < 0.4V, H: >1.0V, 75 ohms) 16 17 Composite video signal ground 18 18 Blanking signal ground 17 19 Composite video signal output (1 Vp-p, 75 ohms, sync: negative) 20 20 Composite video signal input (1 Vp-p, 75 ohms, sync: negative) 19 21 Plug shield (common ground) 21

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3. Function Control Description
Operation, Adjust and Programming

1.POWER Button Push this button to turn the unit on, and press it one more time to turn it off. 2.MENU Button Press this key to pop up the OSD menu under the current selected input mode. 3.TV/AV Button Press this key to select input sources. 4.CHANNEL (+, - ) Buttons Press CHANNEL - or + to browse through the TV channels which are not skipped. Press CHANNEL - or + as up or down select keys to select the OSD menu item. 5.VOLUME (+ ,-) Buttons Press VOLUME - or + to adjust the audio volume increase and decrease. Press VOLUME - or + as right or left select key to select the OSD main menu item.
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4. Circuit Description
(1) SMPS and Voltage Regulator circuit The LCD TV power board should be designed so that AC power supply AC 100V to 240V and the input frequency within 50/60Hz can be applied. (2) Video Circuit

HDMI SCART

VGA MST719 AV

LVDS TO PANEL

S-VIDEO ATV TV
Video Decoder / De-interlace / Scaler MST719

The MST719 is a high performance and fully integrated IC for multi-function LCD monitor/TV with resolutions up to SXGA(1280x1024)/WXGA+(1440x900). It is configured with an integrated triple-ADC/PLL, a multi-standard TV video and audio decoder, a video de-interlacer, a scaling engine, an on-screen display controller, an 8-bit MCU, and a built-in output panel interface. To further reduce system costs, the MST719 also integrates intelligent power management control capability for green-mode requirements and spread-spectrum support for EMI management.

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(3) Audio Circuit

Multiplexer 4052 DESCRIPTION The UTC 4052 analog multiplexers is digitally controlled analog switch. The device feature low ON impedance and very low OFF leakage current. Control of analog signals up to the complete supply voltage range can be achieved. FEATURES *Triple Diode Protection on Control Inputs *Switch Function is Break Before Make *Supply Voltage Range=3.0 Vdc to 18 Vdc *Analog Voltage Range(VDD-VEE)=3.0 to 18V *Note:VEE must beVss *Linearized Transfer Characterisstics *Low-noise-12nV/Cycle ,f1.0kHz Typical

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2-channel multiplexer PI5V330 DESCRIPTION Pericom Semiconductor's PI5V330 is a true bidirectional Quad 2-channel multiplexer/ demultiplexer recommended for both RGB and composite video switching applications. The switch can bi driven from a current output RAMDAC or voltage output composite video source. FEATURES *High-performance solution to switch between video sources *Wide bandwidth:200MHz *Low On-Resistance:3 *Ultra-low quiescent power(0.1µA typical) *Single supply operation:+5.0V *Fast switching:10ns *High-current output:100mA *Packaging(Pb-free & Green Available): 16-pin 300-mil wide plastic SOIC(S) 16-pin 150-mil wide plastic SOIC(W) 16-pin 150-mil wide plastic QSOP(Q)

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Stereo D/A Converter CS4334 DESCRIPTION The CS4334 family members are complete, stereo digital to analog out put systems including interpolation, 1-bit D/A conversion and out put analog filtering in an 8-pin package. The CS4334 support all major audio data interface formats, and the individual devices differ only in the supported interface format. The CS4334 family is based on delta-sigma modulation, where the modulator output controls the reference voltage input to an ultra-linear analog low-pass filter. This architecture allows for infinite adjustment of sample rate between 2kHz and 100kHz simply by changing the master clock frequency. FEATURES *Complete stereo DAC system: Interpolation D/A, Output analog filtering. *24bit Conversion. *96dB dynamic range. *-88dB THD+N *Low clock jitter sensitivity. *Filtered line level outputs *On-Chip digital de-emphasis *Popgaurd technology.

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Audio Processor
DESCRIPTION

MSP3415G

The MSP 34×5G 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 in a single chip. Figure 1-1 shows a simplified functional block diagram of the MSP 34×5G.
FEATURES

* A2-Systems * NICAM-Systems * Very high deviation FM-Mono * BTSC-Stereo * BTSC-Mono + SAP
Block Diagram

*Japan Stereo *FM-Satellite Sound *FM-Stereo-Radio *Standard Selection *Automatic Carrier Mute

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Audio Amp.

TDA1517

Description The TDA1517P is an integrated class-B dual output amplifier in a 18-lead dual in-line (DIP18) plastic medium power package. The device is primarily developed for multi-media applications.

FEATURES
*Requires very few external components *High output power *Fixed gain *Good ripple rejection *Mute/stand-by switch *Load dump protection *AC and DC short-circuit-safe to ground and Vcc *Thermally protected *Reverse polarity safe *Capability to handle high energy on outputs (Vcc=0V) *No switch-on/switch-off plop *Protected against electrostatic discharge

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5. Adjusting Procedure
ITEM Program Menu 1. M/B Voltage confirmation Digital Multimeter Equipments Requirement s Connect with Connect Power to check if Power LED displays the AC Adapter RED light Use voltmeter to measure output position, and check voltage CON1/Pin1-2(12V); CON25/Pin1-2(5V) Please refer to appendix A if there is abnormal phenomenon. 2. Manual VG828 To select the SOURCE then choose VGA. Press MENU button and use the up/down button to select the AUTO SYNC of SCREEN menu.(do twice and confirm the complete action.) 3. Color Temp. Adjustment White-balance calibrate VG828 Chroma/7110 Select SOURCE then choose VGA Enter the factory area Select Calibration Enter Color Temp. to User Enter User Color temp and adjust the R G B offset/gain value a. Natural adjustment Select Natural Auto adjustment R.G.B value, make the color Enter screen b. Warm adjustment Select Warm Auto adjustment R.G.B value, make the color Enter R.G.B adjustment screen c. Cool adjustment Select Cool Enter screen 4. VIDEO adjustment DVD Play DVD interlaced output 5.S-VIDEO adjustment
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Procedure & SPEC

adjustment VGA Pattern Auto adjustment Generator

R.G.B

temperature of the white screen to

adjustment

temperature of the white screen to

Auto adjustment R.G.B number, make the color temperature of the white screen to

R.G.B

adjustment Screen is clear and fluent

Video Cable Set DVD to

DVD S-Video

Play DVD Set DVD to

Screen is clear and fluent

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Cable 6. TV de-interlacing FLUKE 54200 Or other seem rate of equipment 7. VGA PC VGA Cable

interlaced output To send out the TV signal by 54200 To set up the Reduce of OSD to be Strong, and to reduce snowflakes. To set up the Reduce of OSD to be OFF, and the image will display serious snowflakes. PC Mode Each Mode can display normally. If there is a specific Mode that is not appropriate after switch, press Auto Adjust will to automatically adjust for appropriate screen. Confirm PC can automated identify the model of LCD

8. VGA 9. Brightness adjustment Contrast adjustment

TV BOX VGA Cable DVD Cable

Utilize external-connect TV BOX, watching the TV program; the screen is clear and fluent. Play DVD test Select the SOURCE to be or AV2 disc VIDEO Then press MENU Key to enter the adjustment mode. paragraph). Play Sending the signal from DVD test disc (second ESSENTIAL(

PICTURE/VIDEO S-Video

Video Cable A-1) or TV Signal DVD Generator "FLUKE same interlaced

Set DVD to DVD PLUGE w_Gray Scale

54200" or the output Visual rank examining follow: 1. Observing distance is about Adjust BRIGHTNESS to increase the value. Then see this line and adjust the default value to be 50. 35cm 2. Ambient is and approved conditions as equipment.

brightness Selects MENU to exit after finishing. about Screen changes evenly. (contrast: turn from min to max). 150 LUX 3. Observing angle: 90 degree (measure from the central of
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the panel as 90 degrees) 4. Ambient temperatu re: 25±5 C 5. Ambient humidity: 65±20% 10. Display Mode PC Test DVD S-Video Cable Video Cable TV Signal HDMI Cable 11. DVD PICTURE/VIDEO S-Video TINT adjustment Cable TV Signal COLOR adjustment disc HDTV VGA HDMI Select the source to be TV,SCART,Video,S-Video,VGA,HDMI. Press MENU to select the Screen and Select the Display Mode to be 16:9, 4:3, Zoom or Anamorphic. Make sure the each of Display Mode is normal work. Play DVD test Select source then choose VIDEO or S-VIDEO. VIDEO Then press MENU Key to enter the adjustment mode. Sending the signal from DVD test disc (fifth paragraph) ESSENTIALS Set DVD to Hue from to

Video Cable (A-1) GENERTOR interlaced FLUKE54200 output. or the same (COLOR) rank approved equipment. and adjusts maximum

minimum and color present TINT_COLOR variation between black white. and Adjust TINT value to meet the requirement, and collocate blue attachment slice to see the color identical from up to down. Default value is 50. Adjust COLOR value to meet the requirement and collocate blue attachment slice to see the color identical from up and down. Default value is 30 or 25. Select MENU to exit after finishing.

12.

DVD

Play DVD test Select source then choose VIDEO or S-VIDEO. disc VIDEO Sending the signal from DVD test disc (twelfth paragraph) ESSENTIALS Interlaced

PICTURE/VIDEO S-Video 3D COMB FILTER Cable

Video Cable (A-1)

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output(NTSC Mode)

Under S-VIDEO MODE, watch the movable circle pattern is normal without tint. The pattern is normal under 300 and 400. Under VIDEO MODE, watch the movable circle patter, static state is normal without the tint, and movement contains the tint (it is normal phenomenon). Pattern is normal under 300 and 400, if set DVD to PAL, it will contain tint under VIDEO MODE. 13. WINDOWS. DVD OVERSCAN(6%) S-Video Cable Play DVD test Select source then choose VIDEO or S-VIDEO. disc VIDEO Sending the signal from DVD test disc (eighth paragraph) ESSENTIALS Set DVD to interlaced output

Video Cable (A-1)

Watch the screen to check if sees the block screen within SAFE ACTION. 14. WINDOWS DVD Cable Play DVD test Select source then choose VIDEO or S-VIDEO. disc VIDEO Sending the signal from DVD test disc (twelfth paragraph) ESSENTIALS Set DVD to interlaced output FREEZE Window S-Video

Video Cable (A-1)

Select Freeze Windows function to ON and Check if the screen is pause, then restoring the function to Default value OFF.
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15. NTSC/PAL switch

DVD S-Video Cable

Play DVD test Select source then choose VIDEO or S-VIDEO. disc VIDEO Sending the signal from DVD test disc (sixth paragraph) ESSENTIALS Set DVD to interlaced output

Video Cable (A-1)

Switch DVD to output mode NTSC/PAL if there is the action of switch. 16. 480p/480i switch DVD Component Cable Play DVD test Select source then choose VIDEO or S-VIDEO. disc (A-1) Set the DVD to progressive output (P-SCAN) Switch DVD output mode P-SCN ON/OFF, see if there is the action of switch mode on the screen. (480p/480i). 17. Audio adjustment Pattern Generator Sound input External connect left-right trumpet(10W/ 8) a. Volume b. Balance Press < / > Key to Setup the sound volume. Check if the action is normal. Press < / > Key to Setup the balance between left-right trumpet. Check if the action is normal. The initial value is located at middle. i. Sound Mode
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VIDEO Sending the signal from DVD test disc (sixth paragraph).

ESSENTIALS

Any Pattern

Select source Then press MENU Key enter AUDIO adjustment item.

Press < / > Key to setup the surround/off.
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Check if the action is normal. 18. Setting DPMS Power regulator Signal don wire Check OSD if the screen displays count down connect picture. Check if LED show red color. Check if Power is normal. Full White VGA Input (800×600/60 Hz) 19. Language adjustment 20. Defective Cell VG828 Full Red Full Green Full Blue Black AU CMO19" Panel 0.5W Then press Power ON to check if it can turn on and LED show blue color. Check if power is normal. AU CMO19" Panel 21W Select required language. Initial value is set to English or set upon clients' requirement. Black pixels: Section A2 Section B8 RGB: Examination of all the dead pixels in pure Green and pure Red also pure Blue display. any Check if it turns off when the time ends off.

Chroma/6530 with signal. VG828 VGA Cable

White pixels Section A1 Section B2 RGB: Examination of all the dead pixels in pure Green and pure Red also pure Blue display.

Total: Black Pixels + White Pixels + Sparking Pixels 8 21. Remote examination VGA Generator TV Signal Generator DVD or VCD HDTV Player HDMI Player Exam all the functions that remote control offered under all the mode that LCD provides. control Function Pattern

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6. Trouble Shooting Flow Chart

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7. Block Diagram

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