DAEWOO ELECTRONICS DTE-21U6TH User manual

Service Manual
51 Cm STEREO Color Television
MODEL CHASSIS
DTE-21U6TH
PF51T30
CP-785AF
CP-785AF
S/M No.: TCP785AFF0
http : //svc.dwe.co.kr Apr. 2002
DAEWOO ELECTRONICS CO.,LTD.
✔ Caution
: In this Manual, some parts can be changed for improving, their
performance without notice in the parts list. So, if you need the
latest parts information,please refer to PPL(Parts Price List) in
Service Information Center (http://svc.dwe.co.kr).

Service manual CP-785AF
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............................................................................................................... 9
4 - IC description ................................................................................................................................ 10
4-1 TDA936x TV signal processor - TXT with embedded m-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-F665X ....................................................................................................................... 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
PF15T30 .............................. ................................................................................................. 50
(DTE-21U6TH)
7 - Exploded view ............................................................................................................................... 59
8 - PCB Layout....................................................................................................................................
9 - Circuit Diagram..............................................................................................................................
60
61

Service manual CP-785AF
-2-
1-1 Specifications
TV standard PAL, SECAM- B/G, H
Sound system NICAM B/G
FM 2Carrier B/G
Power consumption
21": 95W approx.
Sound Output Power 21" : 3W x 3W (at 60% mod, 10%THD)
Speaker 21" : 5W 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 21" : 51 cm
Channel indication On Screen Display
Program Selection 100 programmes
Aux. terminal 21" : INPUT1(RCA) : Audio / Video
INPUT2(RCA) : Audio / Video In
OUTPUT(RCA) : TV OUT
Headphone jack (3.5 mm) on front of cabinet
Remote Control Unit R-44N08(RD-D90)
Front RCA Jack - Input 2
Pin Signal Description Matching value
1 Video Input 1.0 Vpp+/- 3dB , Impedance 75 ohm
2Audio InputLeft 0.5 Vrms, Impedance > 10k ohm
3Audio Input Right 0.5 Vrms, Impedence > 10k ohm

Service manual CP-785AF
-3-
Rear RCA Jack -output
Pin Signal Description Matching value
1TV Video 1.0Vpp +/- 3dB , Impedence 75 ohm
2
3 TV Audio Right 0.5Vrms at RF sound FM 54% Mod.(27kHz dev.)
TV Audio Left 0.5Vrms at RF sound FM 54% Mod.(27kHz dev.)
Rear SCART [or RCA Jack - Input1 and S-VHS (optional)]
- SCART : 21 pin Euro SCART -> Input1 & S-VHS
- RCA Jack : Input1 (S-VHS not available)
Pin Signal Description Matching value
1N.C.
2Audio Input Right 0.5 Vrms, Impedance > 10 kΩ
3N.C.
4Audio Earth
5Earth
6Audio Input Left 0.5 Vrms, Impedance > 10 kΩ
7N.C.
8N.C.
9N.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

Service manual CP-785AF
-4-
1-2 Channel table
FREQUENCY TABLE CP-785AF
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

Service manual CP-785AF
-5-
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

Service manual CP-785AF
-6-
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

Service manual CP-785AF
-7-
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.

Service manual CP-785AF
-8-
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
Section
For
Adjustments
(Variable)
Items
AGC
R/G BIAS
R/G/B DRIVE
H-PARALLEL
H-BOW
H-SHIFT
V-SLOPE
V-Amplitude
V. S-Correction
V SHIFT
H-WIDTH
EW Parabola
Up-Conner
Dn-Conner
EW Trapezium
Bare
DATA
32
31/31
32/32/32
31
42
25
32
39
13
32
32
32
32
32
32
29"
38
31/31
32/32/28
36
34
30
35
19
27
34
37
20
32
32
29
25"
38
31/31
32/32/32
32
35
30
35
30
25
34
57
17
42
42
31
21"
38
31/31
32/32/32
32
35
30
38
35
25
45
35
00
32
32
29
OptionFor
Function
Change
(OTION)
For screen
Adjustment
04 04 04 04
HOTEL LOCK OFF OFF OFF OFF
HOTEL Max Vol 15 43 43 43
Clock Pr. 01 07 07 07
SVHS ON ON ON OFF
SCREEN 24 31 33 35
ON :
- impossible to change the
- Max. volume is limited.
It is available when HOTEL LOCK is on
Change the reference chanel for
Automatic clock setting
ON : disable S-VHS input
Because each CRT has
different screen Adjusting points
presetted channel
REMARK
old micom : 8/8
Option
0
1
2
3
4
5
6
7
Tuner
Daewoo & Samsung
Daewoo & Samsung
-
-
Daewoo & Samsung
Daewoo & Samsung
-
-
Remote
Controller
For
Daewoo
Remote
controller
For
NEC
Remote
controller

Service manual CP-785AF
-9-
3-3 TV set Alignment
3-3-1. Service Remote controller for Alignment :R-30SVC7 (S/N:48B380SV7)
3-3-2. G2 alignement
-There are 2kinds of screen voltage adjustment
-Method 1 (Use the SVC Remote Controller)
; TV in RF mode without any signal (noise signal)
; Press "SVC" button of Service Remote Controller
; Press "NORMAL" button of SVC Remote controller to change normal-1 mode
; Preset with WP Red/Green/Blue equal to 28-34, Black Red/Green/Blue equal to 28~34
; Press "SCREEN" button of Service Remote controller => Then you can hear the "BEEP" sound
; Adjust screen volume(FBT) when the "BEEP" sound disappeared
- Method 2 (Use the User Remote Controller)
; TV in AV mode without video signal => 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
21”
25” 140 V
29” 140 V
125V~130V
3-3-3. 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.
3-3-4. Focus
-Adjust the Focus volume ( on FBT ) to have the best resolution on screen.
3-3-5. Vertical geometry
-Adjust the Vertical Amplitude, Shift, S-
Correction and Slope to compensate for vertical
distortion.
3-3-6. Horizontal picture centering
-Adjust H Shift to have the picture in the center of the screen.

Service manual CP-785AF
-10 -
3-3-7. 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
H. Bow
H.Width
EW.Parabola
Up Corner
Dw Corner
EW Trapez
3-3-8. AGC
-Adjust the antenna signal level at 68 dBmV±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

Service manual CP-785AF
-11 -
4 -IC description
4-1 TDA936x TV signal processor -Teletext decoder with embedded µ-Controller.
TV-signal Processor
lMulti-standard vision IF circuit with alignment-free PLL demodulator
lInternal (switchable) time-constant for the IF-AGC circuit
lSource selection between 'Internal' CVBS and external CVBS or Y/C signals
lIntegrated chrominance trap circuit
lIntegrated luminance delay line with adjustable delay time
lAsymmetrical ‘delay line type’peaking in the luminance channel
lBlack stretching for non-standard luminance signals
llntegrated chroma band-pass filter with switchable centre frequency
lOnly one reference (12 MHz) crystal required for the µ-Controller, Teletext and the colour decoder
lPAL / NTSC or multistandard colour decoder with automatic search system
lInternal base-band delay line
lRGB 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.
lThe Text/OSD signals are internally supplied from the -Controller/Teletext decoder
lContrast reduction possibility during mixed-mode of OSD and Text signals
lHorizontal synchronisation with two control loops and alignment-free horizontal oscillator
lVertical count-down circuit
lVertical driver optimised for DC-coupled vertical output stages
lHorizontal and vertical geometry processing
lHorizontal and vertical zoom function for 16 : 9 applications
lHorizontal parallelogram and bow correction for large screen picture tubes
µ -Controller
l80C51 µ-controller core standard instruction set and timing
l1µs machine cycle
l32 -128Kx8-bit late programmed ROM
l3 -12Kx8-bit Auxiliary RAM (shared with Display and Acquisition)
lInterrupt controller for individual enable/disable with two level priority
lTwo 16-bit Timer/Counter registers
lWatchDog timer
lAuxiliary RAM page pointer
l16-bit Data pointer
lIDLE and Power Down (PD) mode
l14 bits PWM for Voltage Synthesis Tuning
l8-bit A/D converter
l4 pins which can be programmed as general I/0 pin, ADC input or PWM (6-bit) output
Data Capture
lText memory 10 pages

Service manual CP-785AF
-12 -
lInventory of transmitted Teletext pages stored in the Transmitted Page Table (TPT) and Subtitle
Page Table (SPT)
lData Capture for US Closed Caption
lData Capture for 525/625 line WST, VPS (PDC system A) and Wide Screen Signalling (WSS) bit
decoding Automatic selection between 525 WST/625 WST
lAutomatic selection between 625 WST/VPS on line 16 of VBI
lReal-time capture and decoding for WST Teletext in Hardware, to enable optimised µ-processor
throughput
lAutomatic detection of FASTEXT transmission
lReal-time packet 26 engine in Hardware for processing accented, G2 and G3 characters
lSignal quality detector for video and WST/VPS data types
lComprehensive teletext language coverage
lFull Field and Vertical Blanking lnterval (VBI) data capture of WST data
Display
lTeletext and Enhanced OSD modes
lFeatures of lever 1.5 WST and US Close Caption
lSerial and Parallel Display Attributes
lSingle/Double/Quadruple Width and Height for characters
lScrolling of display region
lVariable flash rate controlled by software
lEnhanced display features including overlining, underlining and italics
lSoft colours using CLUT with 4096 colour palette
lGlobally selectable scan lines per row (9/10/13/16) and character matrix [12x10, 12xl3, 12x16
(VxH)]
lFringing (Shadow) selectable from N-S-E-W direction
lFringe colour selectable
lMeshing of defined area
lContrast reduction of defined area
lCursor
lSpecial Graphics Characters with two planes, allowing four colours per character
l32 software redefinable On-Screen display characters
l4 WST Character sets (GO/G2) in single device (e.g. Latin, Cyrillic, Greek, Arabic)
lG1 Mosaic graphics, Limited G3 Line drawing characters
lWST 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

Service manual CP-785AF
-13 -
-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

Service manual CP-785AFA
-14 -

Service manual CP-785AF
-15 -
Chassis IC marking
OSD languages Capacity Text
CP-785A DW9365/N1/3-BDx
(OTP: TDA9365PS/
N1/5S
English 10 pages Teletext 64K Pan-European,
PINNING
SYMBOL PIN DESCRIPTION
n.u. 1Port 1.3 Not used.
SCL 2I2C bus clock line
SDA 3I2C Data line
SECAM L’out 4Port 2.0 : High when L’selected (PushPull )
OCP 5Port 3.0 : Over Current Protection
RF AGC in 6ADC 1 : For factory use only ( High impedance )
Key-in 7ADC 2 : local key input ( High impedance )
S/SW 8ADC 3 : Scart Slow switching input
VssC/P 9digital 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

Service manual CP-785AF
-16 -
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

Service manual CP-785AF
-17 -

Service manual CP-785AF
-18 -
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 NICAM-
coded 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

Service manual CP-785AF
-19 -
-two selectable analogue pairs of audio baseband input (= two SCART inputs) input level: <2 V RMS,
input impedance: >25 kΩ
-one selectable analogue mono input (i.e. AM sound): Not used in this chassis
-two high-quality A/D converters, S/N-Ratio: >85 dB
-20 Hz to 20 kHz bandwidth for SCART-to-SCART copy facilities
-loudspeaker: one pair of four-fold oversampled D/A converters
output level per channel: max. 1.4 VRMS output resistance: max. 5 kΩ
S/N-ratio: >85 dB at maximum volume max. noise voltage in mute mode: < 10 µV (BW: 20 Hz... 16
kHz)
-one pair of four-fold oversampled D/A converters supplying a pair of SCART-outputs.
output level per channel: max. 2 V RMS, output resistance: max. 0.5 kΩ,
S/N-Ratio: >85 dB (20 Hz... 16 kHz)
Application Fields of the MSP 3415D
In the following sections, a brief overview about the two main TV sound standards, NICAM 728 and
German FM Stereo, demonstrates the complex requirements of a multistandard audio IC.
NICAM plus FM/AM-Mono
According to the British, Scandinavian, 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 sound coding follows the format of the so-called Near
Instantaneous Companding System (NICAM 728). Transmission is performed using Differential
Quadrature Phase Shift Keying (DQPSK. Table below offers an overview of the modulation
parameters.
In the case of NICAM/FM (AM) mode, there are three different audio channels available: NICAM A,
NICAM B, and FM/AM-mono. NICAM A and B may belong either to a stereo or to a dual language
transmission. Information about operation mode and about the quality of the NICAM signal can be read
by the controlling software via the control bus. In the case of low quality (high bit error rate), the
controlling software may decide to switch to the analogue FM/AM-mono sound. Alternatively, an
automatic NICAM-FM/AM switching may be applied.
German 2-Carrier System (DUAL FM System)
Since September 1981, stereo and dual sound programs have been transmitted in Germany using the 2-
carrier system. Sound transmission consists of the already existing first sound carrier and a second
sound carrier additionally containing an identification signal. More details of this standard are given in
Tables below. For D/K very similar system is used.