U4276B TEMIC Semiconductors, U4276B Datasheet - Page 2

• Manufacturer Part Number: U4276B
• Description: FM Multipath Noise Cancellation
• Manufacturer: TEMIC Semiconductors

FSIN / BFSOUT
All information about reception conditions is derived
from the fieldstrength signal. The fieldstrength signal at
FSIN is initially buffered so as not to impair the character-
istics of the IF IC and is available at BFSOUT.
AVFS
The fieldstrength signal at buffer output BFSOUT is aver-
aged over time and applied to input AVFS via an RC
low-pass filter with a large time constant.
MUTE
The function unit MNC can be controlled externally via
this pin. Blanking occurs when the voltage at the MUTE
pin falls below 1 V.
U4276B
2 (8)
FSIN
MUTE
AVFS
40
94 8651
m
A
BFSOUT
40
94 8648
m
Preliminary Information
A
V
S
94 8647
MPXIN / MPXOUT
The MPX signal is fed directly from the FM demodulator
to input MPXIN and is available amplified by a factor of
1.5 at MPXOUT. The MPX signal is blanked out in the
event of multipath interference or when MUTE is acti-
vated externally in the circuit part MNC (Multipath Noise
Canceller). In all other cases, the MPX signal passes
through the IC unchanged.
MPXOUT
MPXIN
94 8650
50 k
50 k
60 k
60 k
W
W
V
W
TELEFUNKEN Semiconductors
W
S
V
S
V
200
S
94 8649
Rev. A1, 05-Sep-96
m
A