TDA7479 Datasheet, PDF (1/7 Pages) STMicroelectronics – SINGLE CHIP RDS DEMODULATOR FILTER

TDA7479
SINGLE CHIP RDS DEMODULATOR + FILTER
VERY HIGH RDS DEMODULATION QUALITY
WITH IMPROVED DIGITAL SIGNAL PROC-
ESSING
HIGH PERFORMANCE, 57KHz BANDPASS
FILTER (8th ORDER)
FILTER ADJUSTMENT FREE AND WITHOUT
EXTERNAL COMPONENTS
PURELY DIGITAL RDS DEMODULATION
WITHOUT EXTERNAL COMPONENTS
ARI (SK INDICATION) AND RDS SIGNAL
QUALITY OUTPUT
4.332MHz CRYSTAL OSCILLATOR
(8.664 and 17.328MHz OPTIONAL)
LOW NOISE CMOS TECHNOLOGY
LOW RADIATION
DESCRIPTION
The TDA7479 recovers the additional inaudible
RDS information which is transmitted by FM radio
broadcasting stations and operates in accord-
ance with the EBU (European Broadcasting Un-
ion) specifications.
BLOCK DIAGRAM AND TEST CIRCUIT
DIP16
SO16
ORDERING NUMBERS:
TDA7479
TDA7479D
The device is made up of two sections: a cas-
caded antialiasing + switched capacitors band-
pass filter for precise RDS band selection and a
demodulating section that performs the extraction
od RDS data stream (RDDA) and clock (RDCL),
to be furher processed by a suitable RDS de-
coder.
Outputs for RDS signal quality and ARI indication
are also present.
C1 27pF 4.332MHz C2 47pF
4
MPX
270pF
8
FILOUT
V_S
100nF
10µF
12
VREF 3
2nd ORDER
ANTIALIASING
FILTER
8th ORDER
SC-BANDPASS
FILTER
-
+
T57
15
OSCIN
13
OSCOUT
14
OSCILLATOR &
DIVIDER
57KHz PLL
FAST ARI
INDICATOR
1187.5Hz
PLL
QUAL DET.
5
OSEL
9
FSEL
16
RDCL
7
ARI
1
QUAL
POLARITY
BIPHASE DEC.
INTEGRAL
BIPHASE DEC.
0
MUX
1
DIFF. DECODER
2
RDDA
TEST LOGIC
10
TM
6
GND
11
EXTRES
D97AU751A
February 1998
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