U3501BM
Cordless Telephone Signal Processor
Description
Cordless telephone signal processor reduces the need for
many external components.
Features
RF Receiver Part
IF converter, FM demodulator, RSSI-digital information
coding, transmit and receive part adjustable and mutable
by serial bus, compander, pre-/ de-emphasis, scrambler
with bypass function
LF Part
Microphone amplifier, earpiece amplifier, compander,
preemphasis, deemphasis, scrambler, descrambler,
digital power management, data management by FSK
Application:
CT1, CT1P, 900 MHz USA standard
Package:
SO28
Block Diagram
MIXO
IFIN1
IFIN2
DACO
RECDC
MIXIN
MIXGND
LOG
LOIN
OSCILATOR
11.15MHz
RSSI
DIVI
Switched Cap.
Divider.
LOEXT
NC
VBAT
D/A
BATD
Battery low
detector
Scrambler frequency
C
INTBUS
D
LPF
Bus
LPF
ADJ.2
Modem
VCC
TXO
Figure 1.
TELEFUNKEN Semiconductors
Rev. A1, 29-Jul-96
Preliminary Information
ÁÁÁ
ÁÁÁ
Serial
ÎÎÎ
ÎÎÎ
Demodulator
Á
Á
IFAMP
RDEMO
LPF
RGAIN
ADJ
DFIL
RXO
ETC
LPF
EXPANDER
Scrambler frequency
EXIN
RECO2
RECOUT
RECO1
RXDAT
FSK
MODEM
TXDAT
MIC1
MIC
MIC2
MICO
TGAIN
TGAIN
PFIL
COMPRESSOR
ADJ.1
COIN
LIMITER
GND
CTC
12386
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