THOMSON CR14300, CR20300, CR20310, CR29411 Basic Service Data

CR14300 FEB/02
Television Basic Service Data
Latin America After Sales
SERVICE DATA INDEX
Adjustment Procedures .................................................................................................. 6
Block Diagrams............................................................................................................... 13
Circuit Description ......................................................................................................... 22
Disassembly ................................................................................................................... 5
IC Pin Descriptions ........................................................................................................ 18
Remote Control .............................................................................................................. 11
Replacement Partlist....................................................................................................... 36
Schematic Diagrams
CR14300 / CR20300 / CR20310 ................................................................................ 63
CR29411 only ............................................................................................................ 64
Servicing Checks ............................................................................................................. 4
Specifications..................................................................................................................2
Troubleshooting.............................................................................................................. 24
Waveforms...................................................................................................................... 32
CR14300
Additional Models:
CR20300, CR20310 &
CR29411
Page
Number
CAUTION: Modification or repair of this unit by unauthorized persons is a direct violation of FCC Rules Part 68.216 and could
result in risk of electric shock. You are urged to contact a qualified factory authorized service facility for repairs.
USE ISOLATION TRANSFORMER WHEN SERVICING
Components having special safety characteristics are identified by a ( ) on schematics and on the parts list in this Service Data and its bulletins. Before servicing this instrument, it is important that the service technician read and follow the "Safety Precautions" in the Basic Service Data.
First Edition - First Printing Copyright 2002 - Thomson multimedia Inc. Printed in U.S.A. - Trademark(s)
®
Registered - Marca(s) Registrada(s)
SAFETY NOTICE
CR14300
1 - GENERAL SPECIFICATIONS - CP02-R0 CHASSI
1.1 Product Models:
CR14300/20300...................................................................MONO conventional model;
CR20310..................................................................................................STEREO SAP;
CR29411..................................................................................................STEREO SAP.
1.2 Power Supply:
a) Power Source Range.........................................................................99VAC to 242VAC.
b) Power Supply: automatic commutation.
c) Power Consumption:
Model CR14300......................................................................................................60W;
Model CR20300......................................................................................................72W;
Model CR20310......................................................................................................80W;
Model CR29411....................................................................................................130W;
STAND BY..................................................................2W (120VAC) and 3W (220VAC).
d) High Voltage (Fly back Anode Voltage) and beam current:
High Voltage: CR14300/20300....................................................................22 ± 1.5 KV;
Beam current - with brightness and contrast at the maximum...................0.7 + 0.1 mA;
CR20310...............................................................................23 + 1.5 KV;
Beam current - with brightness and contrast at the maximum...................0.9 + 0.1 mA;
CR29411............................................................................27.5 + 1.5 KV;
Beam current - with brightness and contrast at the maximum...................1.4 + 0.1 mA;
e) Heating:..............................................................................................6.15 + 0.15 Vrms.
f) FLY BACK Main Power Supply :
“Fly back” Output Voltage CR14300...……..................105 ± 2 V DC; max ripple 2 Vpp;
“Fly back” Output Voltage CR20300 e CR20310…....108.5 ± 2V DC; max ripple 2 Vpp;
“Fly back” Output Voltage CR29411………..................130 ± 2V DC.; max ripple 2 Vpp.
1.3 Tuner and Receiving channel:
Channel Coverage............................……………………. 181 channels VHF/UHF/cable.
Color System: ………….........................................................PAL-N , PAL-M and NTSC;
1.4 Video Signal - Resolution:
Horizontal .......................................................................................................260 lines.
Vertical............................................................................................................330 lines.
1.5 Intermediate Frequency:
Video carrier..................................................................................................45.75Mhz;
Audio carrier..................................................................................................41.25Mhz;
Chrome carrier...............................................................................................42.17Mhz.
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1.6 Carrier System:
Audio...................................................................................................................4.5Mhz;
PAL-M Chrome........................................................................................3,575.611Mhz;
NTSC Chrome..........................................................................................3,579.545Mhz;
PAL-N Chrome.........................................................................................3,582.056Mhz.
1.7 Speaker Output:
CR14300/20300.....................................…………………...............................2.5W rms;
CR20310.........................................................…………………..........2.5W + 2.5W rms;
CR29411..............................................................…………………...........5W + 5W rms.
1.8 Antenna Input Impedance:
VHF/UHF/CABLE................................................75 unbalanced (“F” type connector).
1.9 Terminals:
Rear and front audio (mono) and video input …..................................CR14300/20300;
Rear and front audio (stereo) and video input ...............................................CR20310;
Two rear and one front audio (stereo) and video input...................................CR29411;
Input minimum impedance…....................................................................10kOhms;
Audio input signal level................................................................400 to 800mVrms;
Video input signal level.....................................................................................1Vpp.
Rear Audio output …………………….. ....................................CR29411 and CR20310;
Output maximum impedance......................................................................1kOhms;
Variable output level (maximum volume)....................................................1.5Vrms;
1.10 Dimensions (WxDxH):
CR14300...........................................................................................358.5x383x349 mm;
CR20300..............................................................................................486x488x446 mm;
CR20310..............................................................................................486x488x446 mm;
CR29411..............................................................................................754x529x578 mm.
1.11 Weight:
CR14300................................................................................................................8.9kg;
CR20300..............................................................................................................17.1kg;
CR20310..............................................................................................................17.2kg;
CR29411..............................................................................................................34.3Kg.
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3. ON-SCREEN DISPLAY ADJUSTMENT – SERVICE MODE
3.1 Memory Initialization
If a service repair is undertaken where it has been required to change the MEMORY IC (IC101 and IC102) the following steps should be taken to ensure correct data settings: " memory initialization":
Unplug the power cord from the AC Power Source;
While holding down “MENU” button and “VOLUME –“ button (front panel), plug the power cord in
the AC Power Source (wait 2 seconds before release the buttons).
Turn on the TV set through front panel “POWER” button or remote control.
To certify that the initialization was success executed, it will appear the following message:
To Run Automatic
Tuning Now Plug the Antenna
<No Yes>
ILLUSTRATION 1
3.2 OSD Adjustment – Service Mode
Unplug the power cord from the AC source;
While holding down “MENU” button (front panel), plug the power cord in the AC Source (wait 2
seconds before release the button);
Press and hold the “MENU” and “VOLUME +” buttons (front panel) during 2 seconds;
Turn on the TV set using “POWER” button (front panel or remote control unit).
Press “MENU” button to display the first “SERVICE MENU”.
Press “VOLUME +” and “VOLUME –“ buttons for navigation menus in service mode;
Press “CHANNEL +” and “CHANNEL –“ buttons to select one service menu item;
Press “MENU” button to activate the item adjustment. Press “VOLUME +” or “VOLUME-“ to set the
value adjustment”;
Press “MENU” button to return to the previous “SERVICE MENU” (for another selection).
To exit the service mode, press “MENU” button and turn off the TV set.
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SERVICE
BLKCURR
SERVICE
SERVICE
SERVICE
HP HB HSH VS VA
SERVICE
SBL FFI MAT BKS EVG
SC VSH BLR BLG WR
SERVICE
FMWS SL ADJ A1 A2
WG WB Yn Yp Yav
SERVICE
TC FETRACK AVTRACK MODEL
FSL CL AGCT AGCS RGB
SERVICE
ORIGMAG
VO.3P
3.3 Service Menu Items:
HP = Horizontal Parallelogram RGB = OSD Bright HB = Horizontal Bowl SBL= Services Blanking HSH = Horizontal Shift Adjust FFI = IF Filter VS = Vertical Slope MAT = Color Matrix VA = Vertical Amplitud BKS = Black Stretch SC = Vertical S-Correction EVG = Vertical Guard VSH = Vertical Shift FMWS = Sound PLL BLR = Red Black Level Offset SL = Audio level Adjust BLG = Green Black Level Offset ADJ = Stereo Adjust WR = White Point (red) A1 = Wideband WG = White Point (green) A2 = Spectral WB = White Point (blue) TC = ST current Adjust Yn = Y Delay for NTSC FETRACK = RF Phase1 Time Yp = Y Delay for PAL AVTRACK = AV Phase1 Time Yav = Y Delay for Avin MODEL = Model Identification FSL= Vertical Sync Slicing Level BLKCURR = G2 Adjust CL= Cathode Drive Level ORIGMAG = Factory Picture Settings AGCT = AGC Adjust VO.3P = Software Version AGCS = AGC Delay
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3.4 AGC Adjustment
Apply a color bar pattern (RF Input) with 500µV signal;
Connect a DC Voltmeter, in the AGC pin of the tuner;
Adjust AGCT to Zero and measure the voltage (V1);
Adjust AGCT so that the indication on the voltmeter be (V1) - 1 ± 0.2V.
3.5 Stereo Adjustment
For the adjustments, proceed according to illustration 2;
Adjust output indicated by “A” to tension equal to half of VCC plus 1V ;
Adjust TC to an indication in the microAmpère meter of 24µA in the pin 17 of IC450;
Apply 300Hz/Mono/25KHz of deviation, 250mVrms, in the pin 29 of IC450;
Adjust SL to 500±20mVrms in the pins 15 and 38 of IC450;
Apply in the channel L=300Hz and in the channel R= 3k, 14% of generator Stereo modulation
DBX-NR (EIDEN BTSC );
Change ADJ from 0 to 1. Check A1
and A2 after 1 second (if they varied);
After 1 second returns ADJ to 0 . The stereo circuit will align automatically.
ILLUSTRATION 2
3.6 Vertical Adjustment
Apply a circle Pattern Philips signal (RF Input)
Using the remote control, set the MAGIC mode “ORIGINAL”
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Activate the adjustment mode display (SBL item). Ajust SBL
from 0 to 1. Blanking the bottom of
the screen.
Adjust VSH until the bottom of the pattern be aligned with the reference marks of the mechanical
center on picture tube (the central vertical line in the center of the tube).
Adjust VS until the central line be aligned with the half bottom of the screen (the central line of the
circle pattern in the half cut of the screen)
Return SBL from 1 to
0 value . The image could be compressed or expanded.
Select VA item and set its value to adjust the size of the picture (proportional height and width
picture).
If necessary readjust SC item and set its value to adjust the Linearity (acts in the top of the image)
and VA.
NOTE: The SC and VA adjustments are interdependent (they should be used together). When the image to be decentralized in the vertical, to retouch VSH and/or VS
3.7 Horizontal Adjustment
Apply a Circle Pattern Philips (RF Input)
Using the remote control, set the MAGIC mode “ORIGINAL”
Activate the adjustment mode display (HSH item). Select HSH item and set its value to adjust the
horizontal symmetry of the pattern;
Select HP and HB items and adjust its value if necessary.
3.8 MAGIC Adjustment
Adjustment of original magic should have been according to pattern
Receive the color bar pattern (NTSC signal, RF input)
Connect the oscilloscope probe to the collector of Q830 (cathode G)
Using the remote control, set the image controls as follow:
Brightness: adjust to central position (8 Bars) Contrast: adjust from maximum to minimum (4 Bars) Color: adjust from minimum to maximum (5 Bars) Sharpness: adjust from minimum to maximum (3 Bars) Tint: adjust to the center (8 Bars)
After the image menu preset, turn off the television and activate the service menu. Select
ORIGMAG item;
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Press “VOLUME +” button and change the value from 0 to 1. Turn off the television and the
ORIGINAL MAGIC setup will be registered.
3.9 “SCREEN ( G2 )” Adjustment
Apply a Circle Pattern Philips at the antenna terminal (RF Input).
Using the remote control, set the brightness control to 10 Bars of the bargraph.
Activate the service mode and select BLKCURR item (the menu value should be 0)
Turn the Screen Grid Potentiometer (fly back body) fully counterclockwise (minimum adjustment).
Press the “VOLUME +” button . The register will change to 1 and vertical Deflection will be
blanked.
Turn the Screen Grid Potentiometer slowly clockwise until the power led (stand by) turn on (if the
adjustment of the screen Grid Potentiometer is turned beyond the ideal point, the power led will be turn off)
Press the “VOLUME +” button, it should return the original BLKCURR value. The image will be
return and the adjustment is finished.
3.10 “FOCUS” Adjustment
Apply a Circle Pattern Philips at the antenna terminal (RF Input).
Using the remote control, set the Magic mode “ORIGINAL”
Turn the Focus volume (fly back body) fully counterclockwise once
Adjust the Focus volume until picture is distinct (center of the screen).
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4 – REMOTE CONTROL Models CR14300/20300/20310
NOTE: Consult the original r. c. manufacturer documentation to access the schematic
diagram and the replacement parts list.
The “MENU” button contains the following operations:
MAIN MENU
PICTURE > SOUND > CHANNEL > TUNING > SETUP >
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4 – REMOTE CONTROL
Model CR29411
NOTE: Consult the original r. c. manufacturer documentation to access the schematic
diagram and the replacement parts list.
The “MENU” button contains the following operations:
The “MENU” button contains the following operations:
MAIN MENU MAIN MENU
PICTURE > SOUND >
PICTURE > CHANNEL >
SOUND > TUNING >
CHANNEL > SETUP >
TUNING > SETUP >
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5.2 – BLOCK DIAGRAM OF IC-101 (TDA9380
)
13
5.3 – BLOCK DIAGRAM OF IC-490 (BU4052)
14
5.4 – BLOCK DIAGRAM OF IC-601 (VERTICAL DEFLECTION BOOSTER) TDA9309/TDA8177F
5.5 – BLOCK DIAGRAM OF IC-401 (STEREO AMPLIFIER) TDA7499
15
5.6 – BLOCK DIAGRAM OF IC-450 (STEREO DECODER)
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5.7 – BLOCK DIAGRAM OF IC-430 – LMC568 PLL-“SAP”
____________________________________________
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6 – DESCRIPTION OF THE FUNCTIONS – THE INTEGRATED CIRCUIT´S PINS
6.1 – IC101 (TDA9380)
SIGN PIN DESCRIPTION
OPEN 1 N/C SCL 2 SERIAL CLOCK OUTPUT DAS 3 SERIAL DATA OUTPUT GAME 4 GAME (PWM) SWITCHES A 5 SWITCHES OF THE FRONT PANEL (IN) SWITCHES B 6 SWITCHES OF THE FRONT PANEL AND LED INDICATION (IN) VSH DET 7 SVHS DETECTING (IN) DET SAP 8 SAP DETECTING (IN) GND 9 TERRA SW 0 10 COMMUTATION TO EXTERNAL AV SW 1 11 COMMUTATION TO EXTERNAL AV GND A 12 GROUND SEC PLL 13 PLL DECOUPLING (SECAM) VP 2 14 SUPPLY 2 DEC D05 15 DECOUPLING OF THE DIGITAL PROCESSOR PH2IF 16 FILTER 2 PH1IF 17 FILTER OF SYNCHRONISM GND 3 18 GROUND 3 DET BG 19 FILTER OF (BANDGAP) AVL EWD 20 AVC FILTER VDR B 21 TO VERTICAL OUTPUT B VDR A 22 TO VERTICAL OUTPUT A IF IN 1 23 IF SIGNAL INPUT FILTER S.A.W IF IN 2 24 IF SIGNAL INPUT FILTER S.A.W L REF 25 CURRENT INPUT REF. V. DRIVE VC CAP 26 DECOUPLING OF VERTICAL AGC 27 FILTER OF AGC DEEM/SIFIN1 28 SIF 1 INPUT SDEC SIF 2 29 DECOUPLING OF ÁUDIO (IN 2) GND2 30 GROUND 2 SNDPLL SIF AGC 31 FILTER OF AGC AND SIF AVL REF 32 N/C HOUT 33 OUTPUT OF HORIZONTAL OSC. 15750HZ SAND 34 H PULSE SAND CASTLE ALDEXT OSS AM 35 EXTERNAL AUDIO INPUT IN THE MOD CR14300/20300 – IN THE
OTHERS: N/C
EHT PROT 36 PROTECTION PLLIF 37 PLL IF FILTER VIDEOOUT 38 VIDEO OUTPUT SUPLY 39 SUPPLY CVBS 40 INPUT OF VIDEO PACKAGE GND1 41 GROUND SVHS Y 42 SVHS VIDEO INPUT SVHS CROMA 43 SVHS CHROME VIDEO INPUT AUDOUT 44 AUDIO OUTPUT INS SW2 45 RGB GROUND ERVIN 46 R-Y GROUND G2/YIN 47 G-Y GROUND B2UIN 48 B-Y GROUND
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BCORR/VGUARD 49 ABL BLYIN 50 R 51 RED R G 52 GREEN G B 53 BLUE B VDD A 54 SUPPLY VPE 55 GROUND VDD C 56 SUPPLY OSDGND 57 GND OF OSC 12MHZ XIN 58 CRISTAL OF 12MHZ
XOUT 59 CRISTAL OF 12MHZ RESET 60 RESET CIRCUIT
VDD P 61 SUPPLY 33V MUDO 62 MUTE
PW ON 63 POWER IR 64 IR INPUT
BEAM CURRENT
6.2 - IC 901 (TDA16846)
SIGN PIN DESCRIPTION
OTC 1 OFF TIME CIRCUIT PCS 2 PRIMARY CURRENT SIMULATION RZI 3 REGULATION AND ZERO CROSSING INPUT SRC 4 SOFT-STAR AND REGULATION CAPACITOR OCI 5 OPTO COUPLER INPUT FC2 6 FAULT COMPARATOR 2 (GND) SYN 7 SYNCHRONIZATION INPUT NC 8 NOT CONNECTED REF 9 REFERENCE VOLTAGE AND CURRENT FC1 10 FAULT COMPARATOR 1 (GND) PVC 11 PRIMARY VOLTAGE CHECK GND 12 GROUND OUT 13 OUTPUT ( PWM PULSE) VCC 14 SUPPLY VOLTAGE
6.3 - IC 450 (TDA9855)
SIGN PIN DESCRIPTION
TL 1 TREBLE CONTROL CAPACITOR, LEFT CHANNEL B1L 2 BASS CONTROL CAPACITOR, LEFT CHANNEL B2L 3 BASS CONTROL CAPACITOR, LEFT CHANNEL OUTS 4 OUTPUT SUBWOOFER OR OUTPUT SURROUND SOUND NC 5 NOT CONNECTED OUTL 6 OUTPUT, LEFT CHANNEL LOL 7 INPUT LOUDNESS, LEFT CHANNEL CAV 10 AUTOMATIC VOLUME CONTROL CAPACITOR VREF 11 REFERENCE VOLTAGE 0.5 VCC LIL 12 INPUT LINE, LEFT CHANNEL FIL 13 INPUT AUTOMATIC VOLUME CONTROL, LEFT CHANNEL SOL 14 OUTPUT SELECTOR, LEFT CHANNEL LOL 15 OUTPUT LINE CONTROL, LEFT CHANNEL
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TW 16 CAPACITOR TIMING WIDEBAND FOR DBX TS 17 CAPACITOR TIMING SPECTRAL FOR DBX CW 18 CAPACITOR WIDEBAND FOR DBX CS 19 CAPACITOR SPECTRAL FOR DBX VEO 20 VARIABLE EMPHASIS OUTPUT FOR DBX VEI 21 VARIABLE EMPHASIS INPUT FOR DBX CNR 22 CAPACITOR NOISE REDUCTION FOR DBX CM 23 CAPACITOR MUTE FOR SAP CDEC 24 CAPACITOR DC-DECOUPLING FOR SAP GND 25 GROUND SDA1 26 SERIAL DATA INPUT/OUTPUT (I2C-BUS) SCL 27 SERIAL CLOCK INPUT (I2C-BUS) VCC 28 SUPPLY VOLTAGE COMP 29 COMPOSITE INPUT SIGNAL VCAP 30 CAPACITOR FOR ELECTRONIC FILTERING OF SUPPLY CP1 31 CAPACITOR FOR PILOT DETECTOR CP2 32 CAPACITOR FOR PILOT DETECTOR CPH 33 CAPACITOR FOR PHASE DETECTOR CADJ 34 CAPACITOR FOR PILTER ADJUSTMENT CER 35 CERAMIC RESONATOR ( 503KHz) CMO 36 CAPACITOR DC-DECOUPLING MONO CSS 37 CAPACITOR DC-DECOUPLING STEREO/SAP LOR 38 OUTPUT LINE CONTROL, RIGHT CHANNEL SOR 39 OUTPUT SELECTOR, RIGHT CHANNEL AVR 40 INPUT AUTOMATIC VOLUME CONTROL, RIGHT CHANNEL LIR 41 INPUT LINE CONTROL, RIGHT CHANNEL CPS2 42 CAPACITOR 2 PSEUDO FUNCTION CPS1 43 CAPACITOR 1 PSEUDO FUNCTION EOR 44 OUTPUT EFFECTS, RIGHT CHANNEL VIR 45 INPUT VOLUME CONTROL, RIGHT CHANNEL LDR 46 INPUT LOUDNESS, RIGHT CHANNEL OUTR 47 OUTPUT, RIGHT CHANNEL NC 48 NOT CONNECTED SW 49 FILTER CAPACITOR FOR SUBWOOFER B2R 50 BASS CONTROL CAPACITOR, RIGHT CHANNEL B1R 51 BASS CONTROL CAPACITOR, RIGHT CHANNEL TR 52 TREBLE CONTROL CAPACITOR
6.4 - IC 490 (4052)
SIGN PIN DESCRIPTION
IN1A 2Y0 1 REAR AV 1 INPUT (R) JUST TO CR20310/29411 IN3A 2Y2 2 REAR AV 1 INPUT (R) JUST TO CR20310/29411 OUTA 2Z 3 OUTPUT OF L/R JUST TO CR20310/29411 IN4A 2Y3 4 FRONT AV 2 INPUT (R) JUST TO CR20310/29411 IN2A 2Y1 5 FRONT AV 3 INPUT (R) JUST TO 29411 INIBIT E 6 GROUND VEE VEE 7 GROUND VSS GND 8 GROUND CTL2 G1 9 SW 1 SWITCH CTL1 S0 10 SW 0 SWITCH IN4B 1Y3 11 FRONT (L) INPUT IN1B 1Y0 12 SAP INPUT
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OUTB 1Z 13 OUTPUT IN2B 1Y1 14 AV3 ( L) INPUT TO CR29411 AND VIDEO INPUT TO CR14300/20300 IN3B 1Y2 15 AV1 ( L) INPUT TO CR20310/29411 - AUDIO INPUT TO CR14300/20300 VDD VCC 16 SUPPLY VOLTAGE
6.5 – IC102 (M24CO4MN)
SIGN PIN DESCRIPTION
AO 1 GROUND A1 2 GROUND A2 3 GROUND VSS 4 GROUND DAS 5 SERIAL DATA SCL 6 SERIAL CLOCK TEST 7 GROUND VDD 8 SUPPLY VOLTAGE
6.6 - IC 601 (TDA9309) 14” 20” (TDA8177F) 29”
SIGN PIN DESCRIPTION
Idrive (neg) 1 NON-INVERTING INPUT VCC 2 SUPPLY VOLTAGE (12V) Vp 3 FLYBACK GENERATOR GND 4 GROUND OUT 5 OUTPUT REF 6 OUTPUT STAGE SUPPLY Idrive (pos) 7 INVERTING INPUT
6.7 - IC 401 (TDA7499)
SIGN PIN DESCRIPTION
Vs- 1 DC SUPPLY VONTAGE OUTR 2 OUTPUT RIGHT CHANNEL VS+ 3 DC SUPPLY VOLTAGE (12V) OUTL 4 OUTUPUT LEFT CHANNEL MUTE 5 MUTE Vs- 6 DC SUPPLY VONTAGE (-12V) IN+ 7 INPUT IN- 8 INPUT GND 9 GROUND IN- 10 INPUT IN+ 11 INPUT
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7.0 - OPERATION DESCRIPTION- CP02R0 TELEVISION SET CIRCUIT
Fig.1- Block diagram
3.Tuner
2. TV signal processor and Microprocessor
5. Stereo decoder
6.Audio output
Speaker
Circuit
4. AV switches
7.Video output
8.Horizontal
1. Power Supply
and vertical deflections
CRT
The block diagram in Fig.1 shows how the TV set circuit works divided into 8 basic circuits.
7.1 - POWER SUPPLY
IC901, IC902, IC903, T901, Q901 and surrounding components (9xx)
This is a switching mode power supply designed to operate in AC power source from 99 Volts to 242 Volts and 50/60 Hertz. The main device is the TDA16846 (controller for switching mode power supplies). There are two different operating modes, low power standby and full operation mode.
-Standby: The power supply works in the burst mode and the circuit turn-on during 2 ms and turn-off during 12 ms. In this mode the power consumption is less than 2 Watts in 120 V AC and less than 3 Watts in 220 V AC. In the burst mode, the output voltages are reduced to 10% of the normal values (except microprocessor supply voltage) .
-Full operation mode: This mode is activate by the microprocessor (Remote control or front panel). The output voltages regulation is controlled by the IC903 circuit, opto coupler feedback (IC902) and by the IC901.
The basic output voltages are:
1. 108/128 Volts (CR14300_20300/CR20310_29411) to horizontal circuit;
2. +12 and –12 Volts to audio and vertical circuits;
3. 9 Volts to TV signal processor, stereo decoder and AV circuits;
4. 5 Volts to microprocessor and memory circuits;
5. 3.3 Volts to microprocessor and front panel switches circuits.
There are 3 basic protection mode:
1. AC power source undervoltage: the power supply will turn-off when the AC source is less than 95 Volts.
2. Power consumption limit: when the power consumption exceed 20% of the normal value.
3. Overvoltage outputs shutdown: when the output voltages exceed 15% of the normal values.
7.2 - TV SIGNAL PROCESSOR + MICROPROCESSOR
IC101, IC102 and surrounding components (1xx)
The main device is the TDA9380 (TV signal processor-Teletext decoder with embedded Micro-Controller) that combines the functions of a TV signal processor together with a Micro Controller and Closed Caption decoder. The highlights of this device are:
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