Daewoo CP-785A Schematic

S/M No. : TCP785AEF0

Service Manual

59/68 Cm STEREO Color Television

MODEL

CHASSIS

DTE-25G5THS CP-785A DTE-29G5TH

FS-59T90	CP-785A
FS-68T90

DAEWOO ELECTRONICS CO., LTD.

http : //svc.dwe.co.kr

NOV. 2000

Service manual CP-785A

Contents

1	- Main features .................................................................................................................................	2
	1-1 Specifications ....................................................................................................................	2
	1-2 Channel table ....................................................................................................................	4
2	- Safety instruction ..........................................................................................................................	7
3	- Alignment instructions .................................................................................................................	8
	3-1 Microcontroller configuration : Service mode ....................................................................	8
	3-2 Microcontroller configuration : Option................................................................................	8
	3-3 TV set Alignment ...............................................................................................................	8
4	- IC description ................................................................................................................................	10
	4-1 TDA936x TV signal processor - TXT with embedded μ-Controller. ..................................	10
	4-2 MSP3415D Multistandard Sound Processor.....................................................................	18
	4-3 TDA894xJ Stereo Audio Amplifier.....................................................................................	22
	4-4 TDA835xJ Vertical Amplifier..............................................................................................	23
	4-4-1 TDA8358J...............................................................................................................	24
	4-5 TDA6107Q ........................................................................................................................	25
	4-6 24C08 8 Kbit EEPROM .....................................................................................................	26
	4-7 STR-F6654 .......................................................................................................................	27
5	- Circuit description.........................................................................................................................	29
	5-1 Block diagram....................................................................................................................	29
	5-2 IF .......................................................................................................................................	33
	5-3 Source switching ...............................................................................................................	34
	5-4 u-Controller I/O pin configuration and function..................................................................	34
	5-5 Sound processing..............................................................................................................	35
	5-6 Sound amplification ...........................................................................................................	37
	5-7 Vertical deflection ..............................................................................................................	37
	5-8 Power supply (STR-F6654) ...............................................................................................	39
	5-9 TV start-up, TV normal run and stand by mode operations ..............................................	43
6	-Service parts list.............................................................................................................................	50
	FS-59T90 & FS-68T90 ...........................................................................................................	50
	(DTE-25G5THS & DTE-29G5TH)
7	- Exploded view ...............................................................................................................................	59
8	- PCB Layout ....................................................................................................................................	61
9	- Circuit Diagram..............................................................................................................................	62

Service manual CP-785A

1-1 Specifications

TV standard		PAL, SECAM - B/G, H
Sound system		NICAM B/G
		FM 2Carrier B/G
Power consumption		25" : 113 W approx.
		29" : 118 W approx.
Sound Output Power		25" : 5W x 5W (at 60% mod, 10%THD)
		29" : 5W x 5W (at 60% mod, 10%THD)
Speaker		25" : 7W 8 ohm x 2
		29" : 7W 8 ohm x 2
Teletext system		10 pages memory FASTEXT (FLOF or TOP)
Aerial input		75 ohm unbalanced
Channel coverage		Off-air channels, S-cable channels and hyperband
Tuning system		frequency synthesiser tuning system
Visual screen size		25" : 59 cm
		29" : 68 cm
Channel indication		On Screen Display
Program Selection		100 programmes
Aux. terminal		INPUT1(SCART) : Audio / Video In, S-VHS In(with cable)
		INPUT2(RCA) : Audio / Video In
		OUTPUT(RCA) : TV OUT
		Headphone jack (3.5 mm) on front of cabinet
Remote Control Unit		R-40A01 / R-44N08(RD-D90)
RCA Jack - input 2
Pin	Signal Description		Matching value
1	Video Input		1.0 Vpp+/- 3dB , Impedance 75 ohm
2	Audio Input Left		0.5 Vrms, Impedance > 10k ohm
3	Audio Input Right		0.5 Vrms, Impedence > 10k ohm

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		Service manual CP-785A
RCA Jack output
Pin	Signal Description	Matching value
1	TV Video	1.0Vpp +/- 3dB , Impedence 75 ohm
2	TV Audio Left	0.5Vrms at RF sound FM 54% Mod.(27kHz dev.)
3	TV Audio Right	0.5Vrms at RF sound FM 54% Mod.(27kHz dev.)

Ω

Ω

Ω

Ω

21 pin Euro SCART - Input 1 / S-Video

Pin	Signal Description	Matching value
1	N.C.
2	Audio Input Right	0.5 Vrms, Impedance > 10 kΩ
3	N.C.
4	Audio Earth
5	Earth
6	Audio Input Left	0.5 Vrms, Impedance > 10 kΩ
7	N.C.
8	N.C.
9	N.C.
10	N.C.
11	N.C.
12	N.C.
13	N.C
14	Earth
15	Chroma Input	+/- 3dB for a luminance signal of 1 Vpp
16	N.C.
17	Earth
18	Video In Earth
19	N.C.
20	Video Input / Y Input 1 Vpp +/- 3dB, Impedance 75 ohm
21	Common Earth

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Service manual CP-785A

1-2 Channel table

FREQUENCY TABLE CP-785A

CH	AUSTRALIA	N/Z'land
C00	46.25
C01	57.25
C02	64.25
C03	86.25
C04	95.25
C05	102.25
C5A	138.25
C06	175.25
C07	182.25
C08	189.25
C09	196.25
C10	209.25
C11	216.75
N01	-	45.25
N02	-	55.25
N03	-	62.25
N08	-	203.25
N09	-	210.25
N10	-	217.25
-	-	-	-	-
C21	471.25
C22	479.25
C23	487.25
C24	495.25
C25	503.25
C26	511.25
C27	519.25
C28	527.25
C29	534.25
C30	541.25
C31	548.25
C32	555.25
C33	562.25
C34	569.25
C35	576.25
C36	583.25
C37	590.25
C38	597.25
C39	603.25
C40	610.25
C41	617.25

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Service manual CP-785A

CH	AUSTRALIA	N/Z'land
C42	624.25
C43	631.25
C44	638.25
C45	645.25
C46	652.25
C47	659.25
C48	666.25
C49	673.25
C50	680.25
C51	687.25
C52	694.25
C53	701.25
C54	708.25
C55	715.25
C56	722.25
C57	729.25
C58	736.25
C59	743.25
C60	750.25
C61	757.25
C62	764.25
C63	771.25
C64	779.25
C65	786.25
C66	793.25
C67	800.25
C68	807.25
C69	814.25
C70	-
C71	-
C72	-
C73	-
C74	-
C75	-
C76	-
C77	-
S01	105.25
S02	112.25
S03	119.25
S04	126.25
S05	133.25
S06	140.25
S07	147.25
S08	154.25
S09	161.25

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Service manual CP-785A

CH	AUSTRALIA	N/Z'land
S10	168.25
S11	231.25
S12	238.25
S13	245.25
S14	252.25
S15	259.25
S16	266.25
S17	273.25
S18	280.25
S19	287.25
S20	294.25
S21	303.25
S22	311.25
S23	319.25
S24	327.25
S25	335.25
S26	343.25
S27	351.25
S28	359.25
S29	367.25
S30	375.25
S31	383.25
S32	391.25
S33	399.25
S34	407.25
S35	415.25
S36	423.25
S37	431.25
S38	439.25
S39	447.25
S40	455.25
S41	463.25

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Service manual CP-785A

2 - Safety instruction

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

X-RAY RADIATION PRECAUTION

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 26~28 KV (25” - 29”) at max beam current. The high voltage must not under any circumstances, exceed 29.5 KV (25") or 31 KV (29").

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.

SAFETY PRECAUTION

1.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 high voltage 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 this TV receiver is blown, replace it with the FUSE specified in the Replacement Parts List.

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

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

5.This receiver must operate under AC 240 volts, 5O Hz. NEVER connect to DC supply or any other power or frequency.

PRODUCT SAFETY NOTICE

Many electrical and mechanical parts in this equipment 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 substitutes replacement parts which do not have the same safety characteristics as specified in the parts list may create X-ray Radiation.

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Service manual CP-785A

3 - Alignment instructions

3-1 Microcontroller configuration : Service mode

To switch the TV set into service mode please see instruction below.

1 - Select pr. number 91

2 - Adjust sharpness to minimum value and exit all menu.

3 - Quickly press the key sequence : RED - GREEN - menu

To exit SERVICE menu press menu key or Operate(Std By) key.

In Service Mode press “OK” to stop the microcontroller i.e. the I2C bus is free and the set can be controlled by external equipment. Press “OK” again to allow the microcontroller to control the set again

3-2 Microcontroller configuration : Option

Option	Tuner maker	Remark
0	DAEWOO / SAMSUNG	for Daewoo Remote control
1	DAEWOO / SAMSUNG	for Daewoo Remote control
4	DAEWOO / SAMSUNG	for NEC Remote control
5	DAEWOO / SAMSUNG	for NEC Remote control

3-3 TV set Alignment

3-3-1 - G2 alignement

-TV in AV mode without video signal Þ Black screen.

-TV preset with WP Red, WP Green and WP Blue equal to 32.

-TV preset with Black R, Black G equal to 8.

-Set TV in NORMAL I mode

-Adjust screen volume ( on FBT ) such that the highest cathod cut-off voltage measured on CRT

board, is Vcut off ± 5V.

Screen size	Vcut-off
25”	140V
29”	140V

3-3-2 - White balance

-Select a dark picture and adjust Black G and Black R to the desired colour temperature.

-Select a bright picture and adjust WP Red, WP Green, WP Blue to the desired colour temperature.

3-3-3 - Focus

- Adjust the Focus volume ( on FBT ) to have the best resolution on screen.

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Service manual CP-785A

3-3-4 - Vertical geometry

- Adjust the Vertical Amplitude, Shift, S- Correction and Slope to compensate for vertical distortion.

3-3-5 - Horizontal picture centering

- Adjust H Shift to have the picture in the center of the screen.

3-3-6 - East / West correction

- Adjust the H Parall, H Bow, H Width, EW Parabo, Up Corner, Dw Corner, EW trapez to compensate for geometrical distortion.

H. Parall

EW.Parabola

H. Bow

Up Corner

H.Width

Dw Corner

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Service manual CP-785A

EW Trapez

3-3-7 - AGC

-Adjust the antenna signal level at 68 dBμV± 2 (UHF - CH25)

-Set RF AGC to 0.

-Increase RF AGC level and stop when the level on pin 6 of TDA936x goes below 2.5 Vdc

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Service manual CP-785A

4 - IC description

4-1 TDA936x TV signal processor - Teletext decoder with embedded μ-Controller.

TV-signal Processor

•Multi-standard vision IF circuit with alignment-free PLL demodulator

•Internal (switchable) time-constant for the IF-AGC circuit

•Source selection between 'Internal' CVBS and external CVBS or Y/C signals

•Integrated chrominance trap circuit

•Integrated luminance delay line with adjustable delay time

•Asymmetrical ‘delay line type’ peaking in the luminance channel

•Black stretching for non-standard luminance signals

•lntegrated chroma band-pass filter with switchable centre frequency

•Only one reference (12 MHz) crystal required for the μ-Controller, Teletext and the colour decoder

•PAL / NTSC or multistandard colour decoder with automatic search system

•Internal base-band delay line

•RGB control circuit with 'Continuous Cathode Calibration', white point and black level off set adjustment so that the colour temperature of the dark and the bright parts of the screen can be chosen independently.

•The Text/OSD signals are internally supplied from the -Controller/Teletext decoder

•Contrast reduction possibility during mixed-mode of OSD and Text signals

•Horizontal synchronisation with two control loops and alignment-free horizontal oscillator

•Vertical count-down circuit

•Vertical driver optimised for DC-coupled vertical output stages

•Horizontal and vertical geometry processing

•Horizontal and vertical zoom function for 16 : 9 applications

•Horizontal parallelogram and bow correction for large screen picture tubes

μ-Controller

•80C51 μ-controller core standard instruction set and timing

•1μs machine cycle

•32 - 128Kx8-bit late programmed ROM

•3 - 12Kx8-bit Auxiliary RAM (shared with Display and Acquisition)

•Interrupt controller for individual enable/disable with two level priority

•Two 16-bit Timer/Counter registers

•WatchDog timer

•Auxiliary RAM page pointer

•16-bit Data pointer

•IDLE and Power Down (PD) mode

•14 bits PWM for Voltage Synthesis Tuning

•8-bit A/D converter

•4 pins which can be programmed as general I/0 pin, ADC input or PWM (6-bit) output

Data Capture

• Text memory 10 pages

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Service manual CP-785A

•Inventory of transmitted Teletext pages stored in the Transmitted Page Table (TPT) and Subtitle Page Table (SPT)

•Data Capture for US Closed Caption

•Data Capture for 525/625 line WST, VPS (PDC system A) and Wide Screen Signalling (WSS) bit decoding Automatic selection between 525 WST/625 WST

•Automatic selection between 625 WST/VPS on line 16 of VBI

•Real-time capture and decoding for WST Teletext in Hardware, to enable optimised μ-processor throughput

•Automatic detection of FASTEXT transmission

•Real-time packet 26 engine in Hardware for processing accented, G2 and G3 characters

•Signal quality detector for video and WST/VPS data types

•Comprehensive teletext language coverage

•Full Field and Vertical Blanking lnterval (VBI) data capture of WST data

Display

•Teletext and Enhanced OSD modes

•Features of lever 1.5 WST and US Close Caption

•Serial and Parallel Display Attributes

•Single/Double/Quadruple Width and Height for characters

•Scrolling of display region

•Variable flash rate controlled by software

•Enhanced display features including overlining, underlining and italics

•Soft colours using CLUT with 4096 colour palette

•Globally selectable scan lines per row (9/10/13/16) and character matrix [12x10, 12xl3, 12x16 (VxH)]

•Fringing (Shadow) selectable from N-S-E-W direction

•Fringe colour selectable

•Meshing of defined area

•Contrast reduction of defined area

•Cursor

•Special Graphics Characters with two planes, allowing four colours per character

•32 software redefinable On-Screen display characters

•4 WST Character sets (GO/G2) in single device (e.g. Latin, Cyrillic, Greek, Arabic)

•G1 Mosaic graphics, Limited G3 Line drawing characters

•WST Character sets and Closed Caption Character set in single device

Data Capture

The Data Capture section takes in the analogue Composite Vidéo and Blanking 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 convert the analogue CVBS signal into a digital form. This is done using an ADC sampling at 12MHz. The data and clock recovery is then performed by a Multi-Rate Video Input Processor (MuIVIP). From the recovered data and clock the following data types are extracted WST Teletext (625/525), Closed Caption, VPS, WSS. The extracted data is stored in either memory (DRAM) via the Memory Interface or in SFR locations.

Data Capture Features

- Video Signal Quality detector

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Service manual CP-785A

-Data Capture for 625 line WST

-Data Capture for 525 line WST

-Data Capture for US Closed Caption

-Data Capture for VPS data (PDC system A)

-Data Capture for Wide Screen Signalling (WSS) bit decoding

-Automatic selection between 525 WST/625WST

-Automatic selection between 625WST/VPS on line 16 of VBI

-Real-time capture and decoding for WST Teletext in Hardware, to enable optimised microprocessor throughput

-10 pages stored On-Chip

-lnventory of transmitted Teletext pages stored in the Transmitted Page Table (TPT) and Subtitle Page Table (SPT)

-Automatic detection of FASTEXT transmission

-Real-time packet 26 engine in Hardware for processing accented, G2 and G3 characters

-Signal quality detector for WST/VPS data types

-Comprehensive Teletext language coverage

-Full Field and Vertical Blanking Interval (VBI) data capture of WST data

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Service manual CP-785A

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Service manual CP-785A

Chassis		IC marking				OSD languages	Capacity		Text
CP-785A	DW9365/N1/3-BDx					English	64K		Pan-European,
	(OTP: TDA9365PS/						10 pages Teletext
		N1/5S
PINNING
SYMBOL			PIN			DESCRIPTION
n.u.			1		Port 1.3 Not used.
SCL			2		I2C bus clock line
SDA			3		I2C Data line
SECAM L’ out			4		Port 2.0 : High when L’ selected (PushPull )
OCP			5		Port 3.0 : Over Current Protection
RF AGC in			6		ADC 1 : For factory use only ( High impedance )
Key-in			7		ADC 2 : local key input ( High impedance )
S/SW			8		ADC 3 : Scart Slow switching input
VssC/P			9		digital ground for μ-controller core and peripheral
LED 1			10		port 0.5 ( 8mA current sinking capability )
LED 2			11		port 0.6 ( 8mA current sinking capability )
VSSA			12		analog ground of teletext decoder and digital ground of TV processor
SEC PLL			13		SECAM PLL decoupling
VP2			14		2nd supply voltage TV-processor
DECDIG			15		decoupling digital supply of TV-processor
PH2LF			16		phase-2 filter
PH1LF			17		phase-1 filter
GND3			18		ground 3 for TV-processor
DECBG			19		bandgap decoupling
AVL/EWD			20		East / West drive output
VDRB			21		vertical drive B output
VDRA			22		vertical drive A output
IFIN1			23		IF input 1
IFIN2			24		IF input 2
IREF			25		reference current input
VSC			26		vertical sawtooth capacitor
TUNERAGC			27		tuner AGC output
SIFIN1			28		SIF input 1
SIFIN2			29		SIF input 2
GND2			30		ground 2 for TV processor
SIF AGC			31		AGC sound IF
REF0			32		n.u.
HOUT			33		horizontal output
FBISO			34		flyback input / sandcastle output

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			Service manual CP-785A
	SYMBOL	PIN	DESCRIPTION
	QSS out	35	QSS intercarrier output
	EHT0	36	EHT/Overvoltage protection
	PLLIF	37	IF PLL loop filter
	IFVO	38	IF video output
	VP1	39	main supply voltage TV-processor
	CVBSINT	40	internal CVBS input
	GND1	41	ground 1 for TV-processor
	CVBS/Y	42	external CVBS/Y input
	CHROMA	43	chrominance input (SVHS)
	AMOUT	44	n.u.
	INSSW2	45	2nd RGB insertion input
	R2IN	46	2nd R input
	G2IN	47	2nd G input
	B2IN	48	2nd B input
	BCLIN	49	beam current limiter input
	BLKIN	50	black current input
	R0	51	RED Output
	G0	52	GREEN Output
	B0	53	BLUE Output
	VDDA	54	analog supply of Teletext decoder and digital supply of TV-Processor
			(3.3V)
	VPE	55	OTP programming supply
	VDDC	56	digital supply to core (3.3V)
	OSCGND	57	oscillator ground supply
	XTALIN	58	crystal oscillator input
	XTALOUT	59	crystal oscillator output
	RESET	60	reset
	VDDP	61	digital supply to periphery (3.3V)
	Audio Mute	62	Port 1.0 : Audio mute output (PushPull )
	Power	63	Port 1.1 : Power output (PushPull )
	IR in	64	Interrupt input 0 : R/C Infrared input

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Service manual CP-785A

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Service manual CP-785A

4-2 MSP3415D Multistandard Sound Processor

The MSP 3415D is designed as a single-chip Multistandard Sound Processor for applications in analogue and digital TV sets, video recorders, and PC cards.

MSP 3415D features

-sound IF input

-No external filters required

-Stereo baseband input via integrated AD converters

-Two pairs of DA converters

-Two carrier FM or NICAM processing

-AVC : Automatic Volume Correction

-Bass, treble, volume processing

-Full SCART in/out matrix without restrictions

-Improved FM-identification

-Demodulator short programming

-Autodetection for 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 AM-demodulation

-Reduction of necessary controlling

-Less external components

Basic Features of the MSP 3415D

Demodulator and NICAM Decoder Section

The MSP 3415D is designed to simultaneously perform digital demodulation and decoding of NICAMcoded TV stereo sound, as well as demodulation of FM or AM mono TV sound. Alternatively, two carrier FM systems according to the German terrestrial specs can be processed with the MSP 3415D.

The MSP 3415D facilitates profitable multistandard capability, offering the following advantages:

-Automatic Gain Control (AGC) for analogue input: input range: 0.10 - 3 Vpp

-integrated A/D converter for sound-IF input

-all demodulation and filtering is performed on chip and is individually programmable

-easy realisation of all digital NICAM standards (B/G, I, L and D/K)

-FM-demodulation of all terrestrial standards (include identification decoding)

-no external filter hardware is required

-only one crystal clock (18.432 MHz) is necessary

-high deviation FM-mono mode (max. deviation: approx. ±360 kHz)

DSP-Section (Audio Baseband Processing)

-flexible selection of audio sources to be processed

-performance of terrestrial de-emphasise systems (FM, NICAM)

-digitally performed FM-identification decoding and de-matrixing

-digital baseband processing: volume, bass, treble

-simple controlling of volume, bass, treble

Analogue Section

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