EN 1169.EM5.1ECircuit Descriptions, Abbreviation List, and IC Data Sheets
Signal IF-TER from the tuner is fed to pin 1 and 2, IF circuits of 9.3.5 Power supplies
TDA8887H IC7301 via SAW filter 1352. The AGC voltage for
the tuner can be adjusted in the SAM tuner menu (2nd AGC).The power supplies used by the DW panel are from the main
board 5 V, 8 V, and 33 V (for tuner only). IC7802 LM317T
Source selectionregulates the 5V to +3.3V, +3V, and +3VD. These voltages are
After IF demodulation, the CVBS-PIP-OUT is fed back to mainly used by the DW processor circuitry. The 8V is mainly
TDA888x pin 24 with or without video switching circuit supplied to the IF + video processing circuitry (IC7301
comprises of 7402 (HEF4053). Due to this construction, two TDA888x), and to fast switching IC7803.
independent RF signal pictures can be selectively displayed on
the CRTs screen. See table.
9.4Abbreviation list
Table 9-1 Switching logic for Main and DW Picture
2DNRSpatial (2D) Noise Reduction
3DNRTemporal (3D) Noise Reduction
SEL-TUNER1(Pin SEL TUNER2Selected CVBS
AARAAutomatic Aspect Ratio Adaptation:
6 IC7403)(Pin 7 IC7403)signals
algorithm that adapts aspect ratio to
00Main = Tuner 1
remove horizontal black bars; keeping
DW/PIP = Tuner 2
up the original aspect ratio
01Main = Tuner 1ACIAutomatic Channel Installation:
DW/PIP = Tuner 1algorithm that installs TV sets directly
10Main = Tuner 2from cable network by means of a
DW/PIP = Tuner 2predefined TXT page
ADCAnalogue to Digital Converter
11Main = Tuner 2
AFCAutomatic Frequency Control: control
DW/PIP = Tuner 1
signal used to tune to the correct
frequency
The source signals are fed directly to video processor IC7301. AGCAutomatic Gain Control: algorithm that
The IC performs the source selection internally.controls the video input of the feature-
The video processor IC7301 decodes the CVBS at pin 24 or pin box
29 into YC signals and further process it into YUV signal. AMAmplitude Modulation
Output is at pins 40, 45, and 46. ANRAutomatic Noise Reduction: one of the
The PIP-AUDIO signal is fed to pin 47 of the audio demodulator algorithms of Auto TV
MSP34xx on the SSB. ARAspect Ratio: 4 by 3 or 16 by 9
ArtisticSee OTC 2.5: main processor
Note: When S-VHS is inserted from the rear, the AV2 source ASFAuto Screen Fit: algorithm that adapts
will be disabled. Likewise, when S-VHS is inserted from the aspect ratio to remove horizontal black
side-AV. bars but without throwing away video
information
9.3.4 DW/PIP processingATVSee Auto TV
AUDIO_CAudio Centre
AUDIO_LAudio Left
The SAB908x (IC7801) is a multi-standard PIP controller,
AUDIO_RAudio Right
which can be used in double window or PIP applications. The
AUDIO_SLAudio Surround Left
YUV signals from the video processor IC7301 are fed to pin 79,
81, and 83. The PIP controller will insert the YUV signals from AUDIO-SRAudio surround right
AUDIO_SWAudio Subwoofer
IC7301 with reduced size into the main picture. The main
Auto TVA hardware and software control
picture YUV signals (50 Hz) are fed to pins 100, 2, and 98,
system that measures picture content,
respectively. These signals are used during the DW mode.
and adapts image parameters in a
dynamic way
Inside IC7801, the conversion to the digital environment is
BC-PROTProtection signal to the uP for a too
done with ADCs. Processing and storage (1 MB DRAM) of the
high Beam Current.
video data is done entirely in the digital domain. The
BGSystem B and G
conversion back to the analogue domain is done by DACs.
Internal clocks are generated by PLLs, which lock on to the BLC-INFOBlack Current Info
B-SC1-INBlue SCART1 in
applied horizontal and vertical syncs from the main and sub
B-SC2-INBlue SCART2 in
pictures. The main picture syncs are applied to pin 70 (V) and
B-TXTBlue teletext
pin 94 (H) and the sub picture syncs are applied to pin 72 (V)
BOCMABiMOS One Chip Mid-end
and pin 87 (H).
Architecture: integrated video and
For DW mode, the main picture is compressed horizontally by
chroma decoder
a factor of two and fed directly to the output. After compression,
CLConstant Level: audio output to
a horizontal expansion of two is possible for the main picture.
connect with an external amplifier
The sub picture is also compressed horizontally by a factor two,
but is stored in memory before it is fed to the outputs. ComPairComputer aided rePair
CRTCathode Ray Tube or picture tube
CSMCustomer Service Mode
Post-processed YUV signals are fed to the "fast switching"
CTIColour Transient Improvement:
IC7803 (TDA8601 pins 6, 7, and 8). In normal operation
manipulates steepness of chroma
(without DW), the main picture YUV signals (at pins 2, 3 and 4)
transients
are bypassed by IC7803, and returned back to the main video
CVBSComposite Video Blanking and
processor. When DW mode is active, the compressed YUV
Synchronisation
signals (main and sub pictures) are used and fed to the main
CVBS-TERCVBS terrestrial
video processor. During the PIP mode, only sub-picture YUV
signals are used. The insertion control is made possible by a DACDigital to Analogue Converter
DBEDynamic Bass Enhancement: extra
fast blanking signal from pin 68 of IC7801.
low frequency amplification
DC-filamentFilament supply voltage |
ACEC
