Daewoo cp-776 Service Manual

Service Manual

59 / 66 Cm STEREO Colour Television

CHASSIS : CP-776

DAEWOO ELECTRONICS CO., L

TD.

http://svc.dwe.co.kr Sep,1999

MODEL : DTL- 25G6F

DTL- 25G7F DTL- 28G2F DTL- 28G6F DTL- 28G7F

DTL- 28G8F

CONTENTS

1. Specifications .........................1

2. Safety Instruction .......................3

3. Circuit Block Diagram .....................4

4. Alignment Instructions .....................5

5. IC Description .........................8

6. IC DC Voltage charts .....................33

7. Circuit Description ......................36

8. Service Parts List/Recommendable Spare Parts List .......41

9. Mechanical Exploded V

iew

..................

10. Printed Circuit Board .....................

11. Schematic Diagram .....................56

Specifications

CRT 25” : A59EAK071X11 (PHILIPS)

28” : A66EAK071X11 (PHILIPS) System PAL/SECAM-B/G, D/K, PAL-I, SECAM-L/L’, NTSC-3.58/4.43(Play back) Main Voltage 230V AC, 50Hz

Power Consumption Stand-by mode : 2.5 Watts

Normal operating mode : 25” = 75 Watts

28” = 75 Watts Sound output 7 + 7 Watts, 10 % THD at RF 60 % mod. (1 ) Speaker 12W 8 ohm x 2 EA Antenna 75 ohm unbalanced input Impedance Tuning system Frequency Synthesizer(FS) Tuning System Tuner DT5-BF14D, EL2782-105-B Number of 100 programs program Aux. Terminal 21 pin EURO-SCART jack ( AV input, TV output, RGB input )

21 pin EURO-SCART jack ( AV input, S-VHS input ) RCA type AV input jack

Headphone jack (3.5 mm ) Remote controller R-28B07 with 2 “AA” type batteries Teletext 8 pages memory TOP & FLOF

- West option :English, German/Dutch/Flemish, French, Italian, Spanish/Portuguese, Swedish/Finnish/Danish, Czech/Slovak

- East option : Polish, Czech/Slovak, Rumanian, Hungarian, Servo-croat, German/Dutch/Flemish, French, Italian

- Turkish option : Turkish, English, German/Dutch/Flemish, French, Italian, Spanish/Portuguese, Swedish/Finnish/Danish

OSD language - West : English, German, French, Italian, Spanish, Netherlands, Portuguese,

Danish, Swedish, Finnish, Norwegian

- East : Polish, Rumanian, Czech, Hungarian

21 PIN EURO-SCART

PIN Signal Designation Matching Value

1 Audio Out(linked with 3) 0.5Vrms,lmp<1 (RF 60% MOD) 2 Audio In(linked with 6) 3 Audio Out(linked with 1) 0.5Vrms,lmp<1 (RF 60% MOD) 4 Audio Earth 5 Blue Earth 6 Audio in (linked with 2) 0.5Vrms,lmp>10 7 Blue in 0.7Vpp 3dB ,lmp75 8 Slow(Function) Switching TV:0-2V,PERI:9.5-12V,lmp>10 9 Green Earth

10 NC 11 Green In 0.7Vpp 3dB 12 NC 13 Red Earth 14 NC 15 Red In, C In 0.7Vpp 3 ,lmp75 16 Rapid(Blanking) switching 17 Video Earth 18 Rapid Blanking Earth 19 Video Out 1Vpp 3

,lmp75 20 Video In, Y In 1Vpp 3 ,lmp75 21 Common Earth

20 18 16 14 12 10 8 6 4 2

21 19 17 15 13 11 9 7 5 3 1

dB dB

• Safety Instruction

WARNING: Only competent service personnel may carry out work involving the testing or repair of this equipment.

1. Excessive high voltage can produce potentially hazardous X-RAY RADIATION.To avoid such hazards, the high voltage must not exceed the specified limit. The nominal value of the high

voltage of this receiver is 26 at max beam current. The high voltage must not, under any

circumstances, exceed 29.5 (25"), 30 (28"). Each time a receiver requires servicing, the high voltage should be checked. It is important to use an accurate and reliable high voltage meter.

2. The only source of X-RAY Radiation in this TV receiver is the picture tube.For continued X-RAY RADIATION protection,the replacement tube must be exactly the same type tube as specified in the parts list.

Potentials of high voltage are present when this receiver is operating. Operation of the receiver outside the cabinet or with the back board removed involves a shock hazard from the receiver.

1) Servicing should not be attempted by anyone who is not thoroughly familiar with the precautions necessary when working on highvoltage 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.

If any Fuse in this TV receiver is blown, replace it with the FUSE specified in the Replacement Parts List.

When replacing a high wattage resistor(oxide metal film resistor)in circuit board, keep the resistor 10mm away from circuit board.

4. Keep wires away from high voltage or high temperature components.

5. This receiver must operate under AC230 volts, 50Hz. NEVER connect to DC supply or any other power or frequency.

Many electrical and mechanical parts in this have special safety-related characteristics. These characteristics are often passed unnoticed by a visual inspection and the X-RAY RADIATION protection afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage,wattage,etc. Replacement parts which have these special safety characteristics are identified in this manual and its supplements, electrical components having such features are

identified by designated symbol on the parts list. Before replacing any of these components, read the parts list in this manual carefully. The use of substitute replacement parts which do not have the

list may create X-RAY Radiation.

X-RAY RADIATION PRECAUTION

PRODUCT SAFETY NOTICE

SAFETY PRECAUTION

same safety characterisitics as specified in the parts

Circuit Block Diagram

1. AFT

1.1 Standard B/G,D/K,I and L

1) Set a Signal Generator with

- RF FREQUENCY = 38.9 MHz, 5dBuV

- System = PAL-B/G

2) Connect the Signal Generator RF Output to TP2 (Tuner IF Output). There must be no signal input to the tuner.

3) Set the L109 to TP1(I603, #22) with DC Voltage to 2.5V 0.3V

2. AGC

1) Set a Pattern Generator with RF LEVEL 63 3dBuV, RF Frequency 210. 25MHz(10CH).

2) Connect a OSCILLOSCOPE PROBE to P101 (TUNER AGC INPUT).

3) Set the RBOI to P101(Tuner AGC Input) with DC Voltage to 2.5V 0.3V

3. SCREEN

1) Set the TV to AVI mode(no signal)

2) Set the TV to NORMAL I mode.

3) Press the SVC key on SVC Remocon.

4) Connect a OSCILLOSCOPE PROBE to P904 ( CRT CATHOD R, G, B ).

5) Adjust the SCREEN VOLUME on FBT such that the highest black level voltage 145 5Vdc.

4. WHITE BALANCE

1) Set the TV to NOR I mode.

2) Set the R,G,B LEVEL to CENTER with R,G,B UP/DOWN KEY .

3) Adjust the R,G,B UP/DOWN KEY of the other color which did not appear on the screen to obtain WHITE.

5. FOCUS

1) Apply a RETMA PATTERN signal.

2) Adjust the FOCUS VOLUME on FBT to obtain optimal resolution.

6. GEOMETRY

6.1 VERTICAL SLOPE

1) Apply a RETMA PATTERN Signal.

2) Set the TV to NORMAL I mode.

3) Pressing the V-SLOPE DOWN/UP KEY, the lower half of the screen is blanked .

4) Adjust the border line of blanked picture

coincident with the retma center using

the V-SLOPE DOWN/UP keys.

6.2 VERTICAL CENTER

1) Apply a RETMA PATTERN Signal.

2) Set the TV to NORMAL I mode.

3) Adjust the center of the picture with the V-CENTER DOWN/UP kyes.

Alignment Instructions

6.3 VERTICAL SIZE

has to be done in advance.

1) Apply a RETMA PATTERN Signal.

2) Set the TV to NORMAL I mode.

3) Adjust the upper part of the picture with the V-SIZE DOWN/UP keys.

6.4 VERTICAL S-CORRECTION

1) Apply a CROSSHATCH PATTERN signal.

2) Adjust the S-COR UP/DOWN KEY to obtain

the same distance between horizontal lines.

6.5 HORIZONTAL CENTER

1) Apply a RETMA PATTERN signal.

2) Adjust picture centering with CENTER LEFT/RIGHT keys.

7. EW

7.1 WIDTH

1) Apply a RETMA PATTERN signal.

2) Pressing the EW KEY, the WIDTH OSD appear in the screen.

3) Adjust the over to make a perfect circle with VOL-UP/DOWN KEY.

7.2 PARA

1) Apply a CROSSHATCH PATTERN signal.

2) Pressing the EW KEY, the PARA OSD appear in the screen.

3) Adjust the vertical line to straight with VOL-UP/DOWN KEY.

7.3 CORNER

1) Apply a CROSSHATCH PATTERN signal.

2) Pressing the EW KEY, the CORNER OSD appear in the screen.

3) Adjust the vertical line to straight with VOL-UP/DOWN KEY.

7.4 TRAPI

1) Apply a CROSSHATCH PATTERN signal.

2) Pressing the EW KEY, the TRAPI OSD appear in the screen.

3) Adjust the vertical line to straight with VOL-UP/DOWN KEY.

If EEPROM (I702) has been changed ;

- Option data has to be changed and

- all alignment function has to be readjusted .

Service Remocon ( Part Code : 48B1530SVC )

POW ERPOW ER

STOP

VOL

REMOTE CONTRO LLER R- 30SVCR-30SV C

VOL

EF FEC T

B ASS

TR EBL E

B AL

MIN

MAX

L R

AF T

AU TO

TE ST

TT X

AF T-L’

V-C ENT ER V- SIZ E V-S LOP E S-CO R. SU B B RI.

AG C

H- CEN TER

R- 30S VC

MO DE

WO OFE R

CO NT BR I CO L

MAX MAX MAX

MIN MINMIN

+ +

- - -

+ + +

- - -

- -

- If you need this service remocon, then please order to our subsidiaries.

DW5457 - AE1

The DW5457-AE1 is a single chip teletext decoder for decoding World System Teletext data as well as Video Programming System(VPS), Program Delivery Control(PDC), and Wide Screen Signalling(WSS) data used for PALplus transmissions(line 23). Furthermore, the device provides an integrated C500 based general-purpose, fully 8051-compatible microcontroller

with television specific hardware features. The on-chip display unit for displaying

¡ '

Level 1.5'teletext data can also be used for customer defined on-screen displays. Up to 10 display pages are available internally. The DW 5457-AE1 contains a slicer for VPS, WSS, PDC, and TTX, an accelerating acquisition hardware modul, a

display generator for " Level 1.5 " TTX data, and an 8bit microcontroller running at 250 ns cycle time(min.). The controller with dedicated hardware guarantees flexibility, does most of the internal processing of TTX acquisition, transfers data to/from the external memory interface and receives/transmits data via I2C-firmware user-interface. The slicer combined with dedicated hardware stores TTX data in a VBI buffer of 764Byte. The microcontroller firmware performs all the acquisition tasks(hamming-and parity-checks, page search and evaluation of header control bits) once per field. Additionally, the firmware can provide high-end Teletext-features like Packet-26-handling, FLOF, TOP(in 8/10sheet for details).

(2) Feature

Acquisition

- Feature selection via special function register

- Simultaneous reception of TTX, VPS, PDC, and WSS(line 23)

- Fixed framing code for VPS and TTX.

- Acquisition during VBI

- Direct access to VBI RAM buffer.

- Acquisition of packets x/0 to x/24, x/27, 8/30(firmware)

- Assistance of all relevant checks(firmware)

- 1-bit framing code error tolerance(switchable)

- Complete TTX-acquisition firmware with simple user interface

Display

- Features selectable via special function register.

- 50/60/100/120-Hz display.

- Level 1.5 serial attribute display pages.

- Blanking and contrast reduction output.

- 8 direct addressable display pages.

- 12 x 10-character matrix.

- 96 character ROM(standard G0 character set).

- 156 national option characters for 12 languages(European version).

- 288 characters for X/26 display.

- 64 block mosaic graphic characters.

- 32 characters for OSD in expanded character ROM +32 characters inside OSD box.

- Saturation of basic colors adjustable in 4 steps.

- 8 foreground +8 background colours out of 64 colours.

- Conceal/reveal.

- Transparent foreground/background-inside/outside of a box.

- Contrast reduction inside/outside of a box.

- Cursor(colour changes from foreground to background colour).

- Flash(flash rate 1 s, independent of frame rate).

- Programmable horizontal and vertical sync delay.

- Full screen background colour in outer screen.

- Double size/double width/double height characters.

- Character shadowing.

IC Description

(1) General Description

- Box shadowing.

- Up to 64 Characters in a display row.

- Software selectable pixel frequency(12, 13.7, 16, 19.2 and 24MHz).

Synchronization

- Display synchronization to Sandcastle Pulse

Microcontroller

- 8bit C500-CPU(8051 compatible)

- 24-MHz internal clock(max.)

- 0.25 (min.) instruction cycle.

- Non-multiplexed 8-bit data and 16 ... 19-bit address bus(ROMless Version)

- Eight 16-bit data pointer registers(DPTR)

- Two 16-bit timers

- Watchdog timer

- Capture compare timer for infrared remote control decoding.

- 256-bytes on-chip RAM.

- Display RAM and TXT/VPS/PDC/WSS-Acquisition-Buffer directly accessible via MOVX.

- 10 Kbyte on-chip display-RAM(access via MOVX) for SDA 5457.

- 8 Kbyte on-chip display-RAM(access via MOVX) SDA 5454 to SDA 5457.

- 1 Kbyte on-ship ACQ-buffer-RAM(XRAM, access via MOVX)for SDA 5450 and SDA 5454 to SDA 5457.

- 6 channel 8-bit pulse width modulation unit.

- 2 channel 14-bit pulse width modulation unit.

- ADC with 8-bit resolution(4 multiplexed input channels)

Ports

- One 8-bit I/O-port with open drain output and optional I2C Bus emulation(Port0).

- Two 8-bit multifuncional I/O-ports(Port1, Port3).

- One 4-bit port working as digital or analog inputs for the ADC(Port2).

- One 1-bit Input-port with secondary functions(P4.7/VS/EVEN_ODD).

- One 2-bit I/O-port with optional RAM/ROM address expansion up to 512 Kbyte(P4.0 and P4.1).

Additional Features

- Single external 6MHz crystal, all necessary clocks are generated internally

- CPU clock speed selectable via special funtion registers(7 possible selections between 3 and 24MHz)

(3) Block Diagram

Watchdog-Timer

Capture

Compare-Timer

ADC

Port 2 Port 4 Port 0External Memory Interface

CPU

PWM

Port 3Port 1

CPU-XRAM

VBI-Buffer

Program-ROM

MMU

Display-RAM

Slicer

Acquisition

Character

Font

3 2bit-DACs

Display

Generator

Pin Name Symbol Description

1 P3.1 SYS SECAM-L’ OUT for switching SAW filter K9650-M

- SECAM-L’ : H

- SECAM- L : L

2 P0.7/Open Drain BUSSTOP I2C BUS STOP IN for Computer controlled

alignment in Factory ( Active Low )

3 P0.6/Open Drain SDA Serial data IN/OUT for I2C 4 P0.5/Open Drain SCL Serial clock IN/OUT for I2C 5 P0.4/Open Drain Not Used

6 P0.3/Open Drain 7 P0.2/Open Drain Not Used 8 P0.1/Open Drain

9 P0.0/Open Drain LED LED drive OUT

- Stand-by mode : H

- Operating mode : L ( IR reception : pulse )

10 VSS VSS ground 11 VCC VCC Power Supply 12 XTAL1 OSCIN Input to inverting osc. Amplifier 13 XTAL2 OSCOUT Output of inverting osc. Amplifier 14 P4.0/ALE Not Used 15 RESET RST RESET IN (ACTIVE LOW) 16 P1.7/14BIT PWM Not Used 17 P1.6/14BIT PWM Not Used 18 P1.5/14BIT PWM Not Used 19 P1.4/14BIT PWM Degaussing/SW H : ON

L : OFF 20 P1.3/14BIT PWM MUTE AUDIO MUTE OUT 21 P1.2/14BIT PWM GND GND 22 P1.1/8BIT PWM Not Used 23 P1.0/8BIT PWM Not Used 24 VSSA VSSA Analog GND for Slicer 25 FIL3 FIL3 PLL Loop Filter I/O for Phase Shifting

26 FIL2 Not Used 27 FIL1 Not Used 28 VCCA VCCA Analog Supply for SlicerNot Used 29 IREF IREF Reference Current for Slicer PLLs 30 CVBS CVBS CVBS IN 31 P2.3/8 bit ADC AFT AFT 32 P2.2/8 bit ADC AGC IF AGC INPUT for Auto Tuning System

(4) Pin Description

Pin Name Symbol Description

33 P2.1/8 bit ADC KS Local KEY SCAN IN 34 P2.0/8 bit ADC S/SW S/SW IDENT IN for Automatic

switching between TV/AV mode

- H : AV / RGB mode

- L : TV mode 35 VSS VSS-OSD VSS Ground 36 P3.3/INT1 IR REMOTE IR IN 37 VDD VCC-OSD VDD Power Supply 38 LCIN OSCIN-OSD Not Used 39 LCOUT Not Used 40 P3.7/TXT I/O Not Used 41 P3.6/RXD Not Used 42 P3.5/T1 SYS Standard switch

Meg. modulated video-IF Signal : H Pos. modulated video-IF

Signal : L 43 P3.4/T0 POWER POWER CONTROL OUT 44 P3.2/INT0 Not Used 45 HS/SC Sandcastle IN Sandcastle IN 46 P4.7/VS Not Used 47 R R RED OUT 48 G G GREEN OUT 49 B B BLUE OUT 50 BLANK BL BLANK OUT 51 COR COR Not Used

(CONTRAST REDUCTION OUT) 52 P3.0 T1C2/PWM1 EVEN/ODD EVEN/ODD OUT for non-interlacing

in TTX mode

AT24C16-10PC (E2PROM)

(1) Typical Features

•

IC Bus compatible

•

Low power CMOS Technology

• Eight-byte page(1k, 2k), 16-byte page(4k, 8k, 16k) write buffer

•

Self-Timed Write cycle with Auto-Clear

•

100,000 program/Erase cycles

•

100 Year Data Retention

•

Optional High Endurance Device Available

(2) Description

The AT24C16-10PC is a 16K bit serial CMOS E2PROM internally organized as 2048x8bits. The AT24C16-10PC features a 16 byte page write buffer.

(3) Block Diagram

(4) Pin Description

PIN SYMBOL DESCRIPTION

1-3 A0, A1, A2 Device Address lnputs

4 Vss Ground 5 SDA Serial Data/Address 6 SCL Serial Clock 7 TEST Connect to Vss 8 Vcc +5V Power supply

TDA8844N2 (I2C-bus controlled PAL/NTSC/SECAM TV Processors)

(1) General Description

The TDA8844N2 is I2C-bus controlled single chip TV processors which are intended to be applied in PAL/NTSC television receiver. The IC is mounted in a S-DIP 56 envelope.

(2) Feature

•

Video

- Integrated luminance delay line

- Integrated chroma trap and bandpass filters (auto calibrated)

- Asymmetrical peaking circuit in the luminance channel

- Black stretching of non standard CVBS or luminance signals

•

RGB

- RGB control circuit with “Continuous Cathode Calibralion” and white point adjustment.

•

Input / Output

- Flexible source selection with CVBS switch and Y(CUBS)/C input so that a comb filter can be applied.

- The output signal of the video source select is externally available ( also as CVBS when Y/C input is used).

- External audio input.

- Linear RGB input with fast blanking.

•

Synchronization and Deflection

- Horizontal synchronization with two control loops and alignment free horizontal oscillator.

- Slow start and slow stop of the horizontal drive output to enable low stress start-up and switch-off from the line circuit at nominal line supply voltage.

- Vertical count-down circuit for stable behavior with provisions for non-standard signals.

- Vertical geometry control.

- Vertical drive optimized for DC coupled vertical output stages.

•

Control

- Full I2C bus control, as well for customer controls as for factory alignment.

- All automatic controls have an option for forced mode.

•

Packaging

- SDIP-56(Soldering Dual in-line Packages)

(3) Block Diagram

(4) PIN Description

SYMBOL

ANDIF AUDIOEXT NC NC PLLLF IFVO SCL SDA DECBG CHROMA CVBS/Y VP1 CVBSINT GND1 AUDIOOUT SECPLL CVBSEXT BLKIN BO GO RO BCLIN RI GI BI RGBIN LUMIN LUMOUT BYO RYO BYI RYI REFO XTAL1 XTAL2 DET VP2 CABS10 DECDIG HOUT FBISO PH2LF PH1LF GND2 EWD VDRB VDRA IFIN1 IFIN2 EHTO VSC Irel DECAGC AGCOUT AUDEEM DECSDEM

DESCRIPTION

Sound IF input Extemal audio input not connected not connected IF-PLL loop filter IF video output serial clock input serial data input/output bandgap decoupling chrominance input(S-VHS) external CVBS/Y input main supply voltage 1 (+8V) extemal CVBS input ground1 audio output SECAM PLL decoupling external CVBS input black-current input blue output green output red output beam current limiter input/V-guard input red input for insertion green input for insertion blue input for insertion RGB insertion input Luminance input Luminance output (B-Y) signal output (R-Y) signal output (B-Y) signal input (R-Y) signal input subcamer reference output

3.58 MHz crystal connection

4.43/3.58 MHz crystal connection loop fiter phase detector 2nd supply voltage 1(+8V) CVBS-1 output Decoupling digital supply horizontal output flyback input/sandcastle output phase-2 filter phase-1 filter ground2 east-west drive output vertical drive B output verticla drive A output IF input 1 IF input 2 EHT/overvoltage protection input vertical sawtooth capacitor reterence current input AGC decoupling capacitor tuner AGC output Audio deemphasis Decoupling sound demodulator

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

TDA4470-M(Multistandard Video-if and Quasi Parallel Sound Processing)

(1) Feature

•

5V supply voltage; low power consumption

• Active carrier generation by FPLL principle (frequency-phase-locked-loop)for true synchronous demodulation.

• Very linear video demodulation, good pulse response and excellent intermodulation figures.

• VCO circuit operates at picture carrier frequency, the VCO frequency is switchable for L’-mode.

• 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 level detector)

• Tuner AGC with adjustable take over point

• Alignment-free quasi parallel sound(QPS) mixer for FM/NICAM sound IF signals.

• Intercarrier output signal is gain controlled(necessary for digital sound processing)

• Complete Alignment-free AM demodulator with gain control AF output.

• Separate SIF-AGC with average detection

• Two independent SIF inputs

• Parallel operation fo the AM demodulator and QPS mixer (for NICAM-L stereo sound)

(2) Description

The TDA4470 is an intergrated bipolar circuit for multistandard video/sound IF(VIF/SIF) signal processing in TV/VCR and multimedia applications. The circuit processes all TV video IF signals with negative modulation (e.g., B/G standard), positive modulation(e.g., L standard) and the AM, FM/NICAM sound IF signals.

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