TELEFUNKEN Semiconductors
U4275B
FM-Receiving Condition Analyser and Multipath Noise
Cancellation
Description
The U4275B is a bipolar integrated receiving conditions
analyser as well as multipath noise cancellation circuit.
It is designed for high performance car radio applications.
Features
D
Preparation of the fieldstrength signal
D
Detection of multipath and common channel
interferences
D
Evaluation of the receiving conditions by
microcomputer
D
D
D
D
D
Interrupt output for abruptly occuring interferences
Suitable for analogue as well as digital processing
Mute function controllable by microcomputer
Multipath noise cancellation
Only a few external components necessary
Block diagram
FIL19
20
CRIN
14
Oscillator
Common
channel
detector
Filter
Interference
interrupt
9
INT
FIL26
19
CCHFIL
17
12
Reset
Address
logic
1
FSIN
AVFS
3
Multipath
detector
Analogue
multiplex
11
13
15
ADDR0
ADDR1
OE
ANAOUT
2
BFSOUT
Buffer
MNC
control
Multipath
Noise
Cancellation
(Gain 1.5)
18
4
5
6
8
Bandgap
7
V
S
10
94 8644
16
GND1
MUTE MPFIL
GND2
VREF
MPXIN MPXOUT
Rev. A1: 14.03.1995
Preliminary Information
1