U4275B
INT
+5V
25 k
W
INT
TELEFUNKEN Semiconductors
The controller element detects the absolute value of
occuring multipath interference. This information is
stored in a capacitor which must be connected externally
to MPFIL. The capacitor voltage can be interrogated by
the system controller via ANAOUT.
FIL19 / FIL26
94 8654
Certain types of abruptly occuring interference with
reception require a fast reaction by the receiver. INT
signals such events to other circuit parts by means of
40-
m
s-wide pulses (low active). The output voltage is
limited to 5 V to permit direct activation of a system
controller. A monoblend function can thus be activated on
simple receivers. On antenna-diversity receivers, INT
can activate switchover between antennas.
FIL19
100 k
W
100 nA
94 8657
CCFIL
FIL26
CCFIL
100 k
W
100 nA
94 8655
94 8658
100 k
W
100 nA
The controller element detects the absolute value of
occuring common channel interference. This information
is stored in a capacitor which must be connected
externally to CGFIL. The capacitor voltage can be
selected by the system controller and then available via
ANAOUT.
In order to differentiate the various types of interference,
the amplitudes of a few spectral components of the
fieldstrength signal are determined and filtered in FIL19
and FIL26 for further processing.
VREF
V
S
30 k
VREF
30 k
MPFIL
MPFIL
100 k
W
94 9669
100 nA
94 8656
IF Mute is activated, the reference voltage VREF will
apply to the output MPXOUT. A capacitor of 100 nF
should be connected at VREF for filtering.
4
Preliminary Information
Rev. A1: 14.03.1995
TEMIC [ TEMIC SEMICONDUCTORS ]
