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Service manual SC-140

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5-3-11  Video Sync Processing

To extract the sync information from the video signal, a linear phase low-pass filter eliminates all noise and video
contents above 1 MHz. The sync is separated by a slicer; the sync phase is measured. A variable window can be
selected to improve the noise immunity of the slicer. The phase comparator measures the falling edge of sync, as well
as the integrated sync pulse. The sync phase error is filtered by a phase-locked loop that is computed by the Fast
Processor. All timing in the front-end is derived from a counter that is part of this PLL, and it thus counts synchro-
nously to the video signal. A separate hardware block measures the signal back porch and also allows gathering the
maximum/minimum of the video signal. This information is processed by the FP and used for gain control and
clamping. For vertical sync separation, the sliced video signal is integrated. The FP uses the integrator value to derive
vertical sync and field information. The information extracted by the video sync processing is multiplexed onto the
hardware front sync signal (FSY) and is distributed to the rest of the video processing system.
The data for the vertical deflection, the sawtooth, and the East-West correction signal is calculated by the VCT 38xxA.

5-3-12  Display Processing

In the display processing the conversion from digital YC r C b to analogue RGB is carried out.
In the luminance processing path, contrast and brightness adjustments and a variety of features, such as black-level
expansion, dynamic peaking and soft limiting, are provided. In the chrominance path, the C r C b signals are converted
to 4:4:4 format and filtered by a colour transient improvement circuit. The YC r C b signals are converted by a program-
mable matrix to RGB colour space. The digital OSD insertion circuit allows the insertion of a 5-bit OSD signal.
The OSD signals and the display clock are synchronised to the horizontal flyback.

5-3-13  Chroma Transient Improvement

The intention of this block is to enhance the chroma resolution. A correction signal is calculated by differentiation of
the colour difference signals. The differentiation can be selected according to the signal bandwidth, e.g. for PAL/NTSC/
SECAM or digital component signals, respectively. The amplitude of the correction signal is adjustable. Small noise
amplitudes in the correction signal are suppressed by an adjustable coring circuit. To eliminate ‘wrong colours’,

 which

are caused by over and undershoots at the chroma transition, the sharpened chroma signals are limited to a proper value
automatically.

5-3-14  Video Back-end

The digital RGB signals are converted to analogue RGBs using three video digital-to-analogue converters (DAC) with
10-bit resolution. An analogue brightness value is provided by three additional DACs. The adjustment range is 40 % of
the full RGB range. Controlling the white-drive/analogue brightness and also the external contrast and brightness
adjustments is done via the Fast Processor, located in the front-end. Control of the cutoff DACs is done via I 2 C bus
registers. Finally cutoff and blanking values are added to the RGB signals. Cutoff (dark current) is provided by three 9-
bit DACs. The adjustment range is 60 % of full scale RGB range. The analogue RGB-outputs are current outputs with
current-sink characteristics. The maximum current drawn by the output stage is obtained with peak white RGB. An
external half contrast signal can be used to reduce the output current of the RGB outputs to 50% . Cutoff and white-
drive current measurement are carried out during the vertical blanking interval. They always use the small bandwidth
setting.

Содержание DSC-3210E

Страница 1: ...Service Manual Color Television CHASSIS SC 140 Model DSC 3210E S M No DSC140BEF0 Jul 2002 DAEWOO ELECTRONICS CO LTD http svc dwe co kr...

Страница 2: ...nal processor Teletext decoder with embedded 8 bit Controller 18 4 1 1 Block diagram off the VCT 18 4 1 2 TV signal Processor 18 4 1 2 Controller 19 4 1 4 Teletext Features 19 4 1 5 Displaty OSD Featu...

Страница 3: ...h 44 5 2 9 LSwitch 44 5 2 10 Internal Voltage Stabiliser 44 5 3 Video VCT description 45 5 3 1 Introduction 45 5 3 2 Video Front end 45 5 3 3 Input Selector 45 5 3 4 Clamping 45 5 3 5 Automatic Gain C...

Страница 4: ...nd amplification 55 5 7 1 Power amplifier 55 5 7 2 Mode selection 56 5 8 Vertical deflection 56 5 8 1 Flybac k voltage 56 5 8 2 Protection 56 5 8 3 Guard circuit 56 5 8 4 Damping resistor 56 5 8 5 EAS...

Страница 5: ...channels S cable channels and hyperband Tuning system frequency synthesiser tuning system Visual screen 32 76Cm Channel indication On Screen Display program Selection 100 programmes Aux terminal Remo...

Страница 6: ...9 Full Screen AV2 Monitor Output MSP Version Option 3410 Sound Dffects Off Spatial Graphic Equalizer AV3 Audio Input Dedicated Teletext Page Memory 10 Page Top Teletext Available Selectable in factory...

Страница 7: ...p 0 1V Impedance 75 16 Fast Switching 0 to 0 4V Logic 0 1 to 3V Logic 1 Impedance 75 17 Video Out Earth 18 Video In Earth 19 Video Output 1 Vpp 3dB Impedance 75 20 Video Input 1 Vpp 3dB Impedance 75 2...

Страница 8: ...Service manual SC 140 7 19 Video Output 1 Vpp 3dB Impedance 75 Monitor output Not available for cp885 20 Video Input Y In 1 Vpp 3dB Impedance 75 21 Common Earth...

Страница 9: ...C18 192 25 85 75 C19 201 25 C20 C21 471 25 471 25 471 25 471 25 C22 479 25 479 25 479 25 479 25 C23 487 25 487 25 487 25 487 25 C24 495 25 495 25 495 25 495 25 C25 503 25 503 25 503 25 503 25 C26 511...

Страница 10: ...25 C58 767 25 767 25 767 25 767 25 C59 775 25 775 25 775 25 775 25 C60 783 25 783 25 783 25 783 25 C61 791 25 791 25 791 25 791 25 C62 799 25 799 25 799 25 799 25 C63 807 25 807 25 807 25 807 25 C64 8...

Страница 11: ...25 311 25 311 25 S23 319 25 319 25 319 25 319 25 S24 327 25 327 25 327 25 327 25 S25 335 25 335 25 335 25 335 25 S26 343 25 343 25 343 25 343 25 S27 351 25 351 25 351 25 351 25 S28 359 25 359 25 359 2...

Страница 12: ...from the selected country and named by the TV controlling softw are Within this group the sorting order is fixed by the A TSS list Group II It contains all the pro grams with a strong signal strength...

Страница 13: ...odulation and then a second time with France system selected positive video modulation Special case GB Note for sa tellite recei ver users Before starting ATSS tur n On your satellite r ecei ver and t...

Страница 14: ...equipment 2 Discharge the high potential of the picture tube before handling the tube The picture tube is highly evacuated and if broken glass fragments will be violently expelled 2 If any Fuse in th...

Страница 15: ...menu press menu key or Std By key 3 2 Service mode navigation Pr Up Down remote keys cycle through the service items available Vol remote keys Decrement Increment the values within range 0 7 digit ke...

Страница 16: ...pattern The Frequency of the signal carrier must be accurate Max 10khz deviation fron the nominal channel frequency Find AFT item in service mode Adjust the coil L150 to bring the cursor to central p...

Страница 17: ...zontal picture centring Adjust HOR CEN Horizontal center to have the picture in the center of the screen 3 4 7 Eau West comection Adjust the PARABOLA HOR WIDTH CORNER HOR PARAL EW TRAPEZ H BOW to comp...

Страница 18: ...ual SC 140 17 CORNER EW TRAPEZ 3 4 8 AGC Adjust the antenna signal level at 70 dB V 2 Tune a colour bar pattern Find the AGC item in service mode Adjust AGC volume RB10 to bring the cursor to central...

Страница 19: ...mbedded 8 bit Controller 4 1 1 Block diagram of the VCT 4 1 2 TV signal Processor Four composite video inputs two S VHS inputs AnalogueYC r C b input Composite video monitor Multistandard colour decod...

Страница 20: ...apture compare module watchdog timer 14 bit PWM for voltage synthesis Four 8 bit PWMs 10 bit ADC with 15 1 input MUX I2C bus master interface 24 programmable I O ports 80C51 controller core standard i...

Страница 21: ...nking Signal CVBS and from this extracts the required data which is then decoded and stored in memory The extraction of the data is performed in the digital domain The first stage is to select and con...

Страница 22: ...aptive Comb filter Panorama Scaler 4 1 11 IC marking and version Chassis OSD languages ATSS countries Text SC 140 VCT3834A Pan European Latin Cyrillic Greek GB France Germany Italy Belgium Spain Austr...

Страница 23: ...tooth Output 36 EW OUT Vertical Parabola Output 37 SENSE IN SenseADC Input 38 GNDM SUPPLY Ground MADC Input 39 RSW1 OUT Range Switch1 for MeasurementADC 40 RSW2 OUT Range Switch2 for MeasurementADC 41...

Страница 24: ...3 3V GND GND GND XREF VRD GND 5V B out G out R out SVM out RSW2 RSW1 GND SENSE EW VERTQ VERT HFLB Power 1 2 3 4 5 7 8 9 10 17 19 20 21 22 23 24 25 26 27 28 29 31 30 32 18 11 12 13 14 15 16 6 AGC S B...

Страница 25: ...terrestrial TV sound standards Precise bit error rate indication Automatic switching from NICAM to FM AM or vice versa Improved NICAM synchronisation algorithm Improved carrier mute algorithm Improved...

Страница 26: ...ian Spanish and French TV standards high quality stereo sound is transmitted digitally The systems allow two high quality digital sound channels to be added to the already existing FM AM channel The s...

Страница 27: ...PAL UK D K 6 5 6 2578125 D K1 FM Stereo SECAM East USSR 6 5 6 7421875 D K2 6 5 5 85 D K NICAM FM Mono NICAM Hungary Architecture of MSP341x Pin connections and short description Pin No Pin Name Type S...

Страница 28: ...Reference ground 1 high voltage part 36 SC1_OUT_R Out Scart output 1 right 37 SC1_OUT_L Out Scart output 1 left 38 NC Not Connected 39 AHVSUP Analog power supply 8 0V 40 CAPL_M Volume capacitor MAIN 4...

Страница 29: ...es Alignment free AFC without external reference circuit polarity of the AFC curve is switchable VIF AGC for negative modulated signals peak sync detection and for positive modulation peak white black...

Страница 30: ...SIF2 SIF2 input symmetrical 4 3 4 Block diagram Offset 26 18 20 21 14 VCO l switch VCO Control phase shift FPLL VIF amp Loop filter comp optional 4 9 16 AM det FM det 25 24 17 Cref 23 13 22 19 6 7 8 1...

Страница 31: ...4 4 TDA894xJ Stereo AudioAmplif ier The TDA8944J TDA 8946J is a dual channel audio po wer amplifier with an output power of 2 x 7W 2 X 15W at an 8 load and a 12V supply The circuit contains two Bridg...

Страница 32: ...Service manual SC 140 31 Block diagram TDA8944J...

Страница 33: ...t combines Bipolar CMOS and DMOS devices MOS transistors are used in the output stage because of the absence of second breakdown 4 5 1 TDA8357J Features Few external components High efficient fully DC...

Страница 34: ...urrent from the diode modulator circuit Features Few external components Highly efficient fully DC coupled vertical output bridge circuit Short rise and fall time of the vertical flyback switch Guard...

Страница 35: ...Service manual SC 140 34...

Страница 36: ...pical bandwidth of 5 5 MHz for an output signal of 60 Vpp High slew rate of 900V s No external components required Very simple application Single supply voltage of 200V Internal reference voltage of 2...

Страница 37: ...Service manual SC 140 36 Block diagram TDA6107Q...

Страница 38: ...erial clock 7 WC Write control 8 Vcc Supply voltage 4 Vss Ground The memory device is compatible with the I2C memory standard This is a two wire serial interface that uses a bi directionnal data bus a...

Страница 39: ...nd control IC designed for flyback converter type switch mode power supply applications 4 8 2 Features Small SIP fully isolated molded 5 pins package Many protection functions Pulse by pulse overcurre...

Страница 40: ...Circuit current in 4 5 IIN on 30 mA operation Circuit current in non 4 5 IIN off 100 mA A operation Maximum OFF time TOFF max 45 55 SEC Minimum time for input of 1 5 TTH 2 1 0 SEC quaxi resonant signa...

Страница 41: ...ectrical characteristics IC PINS RATING NUMBER MIN TYPE MAX Drain to source break 3 2 VDSS 650 V voltage Drain leakage current 3 2 IDSS 300 A On resistance 3 2 RDS on 1 95 Switching time 3 2 tf 2 50 n...

Страница 42: ...Service manual SC 140 41 5 Circuit description 5 1 Block diagram...

Страница 43: ...tial input Pin 6 7 of the VIF amplifier 5 2 2 Vision IF Amplifier This amplifier consists of three AC coupled amplifier stages Each differential amplifier is gain controlled by the automatic gain cont...

Страница 44: ...ner AGC to generate the tuner AGC current at Pin 11 open collector output The take over point of the tuner AGC can be adjusted at Pin 10 by a potentiometer or an external dc voltage from interface cir...

Страница 45: ...AGC is related to the average level of AM or FM carrier and controls the SIF amplifier to provide a constant SIF signal to the AM demodulator and QPS mixer 5 2 7 Quasi Parallel Sound QPS Mixer The QPS...

Страница 46: ...rier chrominance signal These inputs are internally biased and have a fixed gain amplifier 5 3 4 Clamping The composite video input signals are AC coupled to the IC The clamping voltage is stored on t...

Страница 47: ...lour standards The colour killer uses the burst phase burst frequency measurement to identify a PAL NTSC or SECAM colour signal For PAL NTSC the colour is switched off killed as long as the colour sub...

Страница 48: ...b signals are converted by a program mable matrix to RGB colour space The digital OSD insertion circuit allows the insertion of a 5 bit OSD signal The OSD signals and the display clock are synchronis...

Страница 49: ...o BCL limited drives and brightness 5 3 17 Analogue RGB Insertion The VCT 38xxA allows insertion of external analogue RGB signals The RGB signal is key clamped and inserted into the main RGB by the Fa...

Страница 50: ...cuitry VSUP D 5 4 Microcontroller 5 4 1 Introduction The TV controller basically consists of the CPU RAM ROM and a number of peripheral modules For instance a memory banking module is included to allo...

Страница 51: ...s as input for the analogue to digital converter Controller I O pin configuration and function table pin name description To reduce power consumption in stand by mode all ports not used are configured...

Страница 52: ...mall horizontal geometrical error typically 8 linear ZOOM 16 9 133 100 Picture is displayed 16 9 picture letter box filling the full screen format with 430 active width and height lines PANORAMA 100 1...

Страница 53: ...1 or S SW 2 represent the SLOW SWITCHING inputs of the first SCART AV 1 or second SCART AV 2 these each being pin number 8 5 F SW 1 represents the FAST SWITCHING input of the first SCART AV 1 on pin n...

Страница 54: ...en broadcaster the intended language that the teletext page should be displayed in As there are only 3 bits there are only 8 codes available to cover all the possible language combinations This means...

Страница 55: ...n Spanish Dutch Danish Finnish Norwegian Swedish Greek Polish Hungarian Czech Slovakian Rumanial Russian 5 6 Sound processing 5 6 1 Analogue sound IF input section The input pins ANA_IN1 and ANA_IN of...

Страница 56: ...uality and automatically switches to the analogue sound carrier 1 if the transmission quality is too poor To avoid unwanted automatic switching the threshold levels mono to stereo and stereo to mono a...

Страница 57: ...through the deflection coils measured as voltage across R398 which provides internal feedback information The voltage across R398 is proportional to the output current 5 8 1 Flyback voltage The flybac...

Страница 58: ...designed for flyback converter type switch mode power supply applications 5 9 2 Power supply primary part operations An oscillator generates pulses signals which turn on and off a MOSFET transistor 5...

Страница 59: ...does not increase to the set voltage immediately after the control circuit starts operating VIN starts dropping However as this winding voltage reaches the set value before VIN voltage drops to the s...

Страница 60: ...Service manual SC 140 59 5 9 2 2 STR F6654 oscillating operation...

Страница 61: ...by C1 and R1 is the OFF time of the MOSFET When C1 voltage falls to around 3 7V the STR F6654 internal oscillator is reversed again and the MOSFET turns ON C1 is quickly charged to around 6 5V The MO...

Страница 62: ...ulator This regulator provides 5V 3 3V DC voltage to I501 microcontroller power supply pins pin 3 pin 54 and to the reset pulse circuit which provides reset pulse to I501 microcontroller reset pin pin...

Страница 63: ...hing off the microcontroller switches TV set to stand by mode decreasing power pin voltage pin 1 5 10 2 TV normal run and stand by mode operations Depending on remote control commands I501 microcontro...

Страница 64: ...he ground and I810 controlled rectifier gate pin is set to low no conducting So current from 14V DC voltage from T801 SMPS transformer pin 13 does not flow through Q811 and Q810 transistors but flows...

Страница 65: ...udes an IC error amplifier I806 which corrects unexpected DC voltage variations on this line power supply IC delivery during TV set normal run power supply line IC power supply delivery Remarks 143V F...

Страница 66: ...C H I N G C I R C U I T T801 SM PS TRA N S I501 M A I N IC OCP FB D801 D804 GRAETZ BRIDGE 16 D821 I810 controlled rectifier HIGH C841 C840 R713 1 3 1 2 61 64 56 54 7 63 CONDUCTING I R I N com supply...

Страница 67: ...ier gate pin is set to high and I810 is conducting So current flows from pin 16 SMPS transformer to the ground via I804 optocoupler and Q810 and Q811 transistors which are conducting In these conditio...

Страница 68: ...304J C MYLAR 400V PU 0 3MF J C499 CEYD1H689W C ELECTRO 50V RHD 6 8MF 16X35 5 C619 CEXF1E102C C ELECTRO 25V RUS 1000MF 13X20 TP C801 CL1UC3474M C LINE ACROSS 0 47MF 1J UCVSNDF SV Q O C805 CEYN2G181P C...

Страница 69: ...SEMI 2KV BL N 1000PF K T C823 CEXF1E102V C ELECTRO 25V RSS 1000MF 13X20 TP C832 CEXF1E102V C ELECTRO 25V RSS 1000MF 13X20 TP C841 CEXF1C332V C ELECTRO 16V RSS 3300MF 16X25 TP z_loc z_parts_code parts...

Страница 70: ...PPING C605 CEXF1E470V C ELECTRO 25V RSS 47MF 5X11 TP C608 CEXF1H100V C ELECTRO 50V RSS 10MF 5X11 TP C610 CEXF1H100V C ELECTRO 50V RSS 10MF 5X11 TP z_loc z_parts_code parts_name parts_descr C611 CEXF1H...

Страница 71: ...C CERA 50V B 1000PF K AXIAL C151 CCZF1H103Z C CERA 50V F 0 01MF Z C154 CCZF1H103Z C CERA 50V F 0 01MF Z C160 CCZF1H103Z C CERA 50V F 0 01MF Z C161 CZCH1H220J C CERA 50V CH 22PF J AXIAL C163 CCZF1H103Z...

Страница 72: ...DIODE ZENER UZ 5 6BM DA16 DUZ5R6BM DIODE ZENER UZ 5 6BM DA27 DUZ5R6BM DIODE ZENER UZ 5 6BM DA32 DUZ5R6BM DIODE ZENER UZ 5 6BM J002 85801065GY WIRE COPPER AWG22 1 0 65 TIN COATING J003 85801065GY WIRE...

Страница 73: ...IRE COPPER AWG22 1 0 65 TIN COATING J934 85801065GY WIRE COPPER AWG22 1 0 65 TIN COATING L105 5CPZ479K02 COIL PEAKING 4 7UH K AXIAL 3 5MM L153 5CPZ120K02 COIL PEAKING 12UH K AXIAL 3 5MM L501 5CPZ479K0...

Страница 74: ...AZ101J R CARBON FILM 1 6 100 OHM J R586 RD AZ271J R CARBON FILM 1 6 270 OHM J R587 RD AZ101J R CARBON FILM 1 6 100 OHM J z_loc z_parts_code parts_name parts_descr R588 RD AZ101J R CARBON FILM 1 6 100...

Страница 75: ...OHM J RA14 RD AZ101J R CARBON FILM 1 6 100 OHM J RA15 RD AZ750J R CARBON FILM 1 6 75 OHM J RA16 RD AZ750J R CARBON FILM 1 6 75 OHM J z_loc z_parts_code parts_name parts_descr RA17 RD AZ750J R CARBON...

Страница 76: ...140 75 z_loc z_parts_code parts_name parts_descr R902 RD AZ472J R CARBON FILM 1 6 4 7K OHM J R903 RD AZ750J R CARBON FILM 1 6 75 OHM J R904 RD AZ750J R CARBON FILM 1 6 75 OHM J z_loc z_parts_code part...

Страница 77: ...SPEC PLATE PART NAME 02 02 15 HJLEE Checked by 02 02 15 BKCHOI MODEL Approved by QTY 1 COVER BACK MASK FRONT HOLDER CORD CLOTH BLACK CLOTH BLACK HOLDER CORD SPRING 4 3 1 6 1 1 1 CR T2 0 EXPLODED VIEW...

Страница 78: ...Service manual SC 140 77 8 PCB Layout...

Страница 79: ...Service manual SC 140 78 9 Schematic Diagram...

Страница 80: ...DAEWOO ELECTRONICS CO LTD 686 AHYEON DONG MAPO GU SEOUL KOREA C P O BOX 8003 SEOUL KOREA TELEX DWELEC K28177 8 CABLE DAEWOOELEC...

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