TDA8961 Philips Semiconductors, TDA8961 Datasheet - Page 3

• Manufacturer Part Number: TDA8961
• Description: ATSC/NTSC digital TV front-end chipset
• Manufacturer: Philips Semiconductors

Philips Semiconductors
GENERAL DESCRIPTION
The TDA8961 is an Advanced Television Systems
Committee (ATSC)-compliant demodulator and FEC
decoder for reception of 8-VSB modulated signals for
terrestrial and cable applications:
An application using the TDA8961 and the TDA8980
NTSC/ATSC TV input processor for TV and Multi-Media is
shown in Fig.1. A tuner converts the incoming RF signal to
a fixed IF centered at 44 MHz. The output signal from the
tuner is filtered and fed to the TDA8980 which performs the
following functions:
2000 May 19
handbook, full pagewidth
Terrestrial: reception of 8-VSB modulated signals via
standard 6 MHz VHF/UHF terrestrial TV channels (TV
channels 2 to 69 in the United States).
Cable: reception of 8-VSB modulated signals via
standard 6 MHz VHF/UHF cable TV channels.
Decodes the analog NTSC signals: The audio signals
are digitized, using on-chip audio stereo A/D converters,
into an I
using on-chip video A/D converters, into an ITU656
stream.
ATSC Digital Terrestrial TV
demodulator/decoder
2
S-bus stream; the video information is digitized,
TUNER
I
2
C
Fig.1 Front-end design for a hybrid TV system using the TDA8980 and TDA8961.
FILTER
FILTER
NTSC
FLAT
SAW
SAW
TVIFIN
VSBIFIN
TUNERAGC
I
2
C
X12MOUT
TDA8980
12 MHz
D9 to D0
REF12M
VIFAGC
X12MIN
VCLK
master
I
2
C
3
Although the TDA8980 has an internal 2-D comb filter,
external filters such as a 3-D comb filter and other picture
improvement devices can easily be connected. Sound can
be decoded using an external device such as the
TDA9851 I
decoder. This IC has an internal switch allowing it to
process either analog NTSC IF or digital 8-VSB IF signals.
A 12 MHz clock signal is generated using a 12 MHz crystal
connected to the TDA8980. The TDA8961 also uses this
clock signal which is fed from the TDA8980 to pin XTALI of
the TDA8961.
I
ADCLK
ADIN9 to ADIN0
XTALI
AGCOUT
Down converts the incoming 6 MHz wide 8-VSB IF
signal to a low-IF signal centered at 4 MHz: The low-IF
signal is then digitized, using an on-chip 10-bit A/D
converter, and fed to the TDA8961 for further
processing. In this application, AGC is also managed by
the TDA8980 so that no other external components,
such as an operational amplifier loop integrator, are
required.
2
C
PDI0 PDISYNC PDIVAL
2
C-bus controlled economic BTSC stereo
serial MPEG-2 transport
TDA8961
stream input
PDICLK PDIERR
PDO7 to PDO0
PDOSYNC
PDOERR
PDOCLK
PDOVAL
Objective specification
MGU085
TDA8961
transport
MPEG-2
stream