TDA7331 Datasheet, PDF (1/7 Pages) STMicroelectronics – SINGLE CHIP RDS DEMODULATOR+ FILTER

TDA7331
SINGLE CHIP RDS DEMODULATOR + FILTER
VERY HIGH RDS DEMODULATION QUALITY
WITH IMPROVED DIGITAL SIGNAL PROC-
ESSING
HIGH PERFORMANCE, 57KHz BANDPASS
FILTER (8th ORDER)
PURELY DIGITAL RDS DEMODULATION
WITHOUT EXTERNAL COMPONENTS
ARI INDICATION AND RDS SIGNAL QUAL-
ITY OUTPUTS
4.332MHz CRYSTAL OSCILLATOR
(8.664 and 17.328MHz SELECTABLE OP-
TIONS)
LOW NOISE CMOS TECHNOLOGY
LOW RADIATION
DIP20
SO20
ORDERING NUMBERS:
TDA7331
TDA7331D
DESCRIPTION
The TDA7331, an improved version of
TDA7330B, 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.
The device is made up of two sections: a cas-
BLOCK DIAGRAM and TEST CIRCUIT
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
1
MPX
270pF
4
FILOUT
V_S
100nF
10µF
16
VREF 2
2nd ORDER
ANTIALIASING
FILTER
8th ORDER
SC-BANDPASS
FILTER
-
+
T57
11
OSCIN
10
OSCOUT
9
OSCILLATOR &
DIVIDER
57KHz PLL
FAST ARI
INDICATOR
1187.5Hz
PLL
QUAL DET.
3
OSEL
18
FSEL
12
RDCL
15
ARI
14
QUAL
POLARITY
BIPHASE DEC.
INTEGRAL
BIPHASE DEC.
0
MUX
1
13
DIFF. DECODER
RDDA
TEST LOGIC
19
TM
5
GND
6,7,8,17
N.C.
20
EXTRES
D97AU686B
February 1998
1/7