U3900BM
Programmable Telephone Audio Processor
Description
The programmable telephone audio processor U3900BM
is a linear integrated circuit for use in feature phones,
answering machines, fax machines and cordless phones.
It contains the speech circuit, tone-ringer interface with
DC/DC converter, sidetone equivalent and ear-protection
rectifiers. The circuit is line-powered and contains all
components necessary for signal amplification and
adaptation to the line. The U3900BM can also be supplied
via an external power supply. An integrated voice switch
with loudspeaker amplifier enables hands-free or loud-
hearing operation. With an anti-feedback function,
acoustical feedback during loudhearing can be reduced
significantly. The generated supply voltage is suitable for
a wide range of peripheral circuits.
Features
D
D
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Speech circuit with anti-clipping
Tone ringer interface with DC/DC converter
Speaker amplifier with anti-distortion
Power-supply management, regulated, unregulated
and a special supply for electret microphone
Voice switch
CLID + SCWID
DTMF generator
Switch matrix
Line current information
Fully programmable
Watchdog
Benefits
D
Savings of one piezoelectric transducer
D
Complete system integration of analog signal
processing on one chip
D
Very few external components
D
Highly integrated solution
D
Extremely versatile due to full programmability
Applications
Feature phone, answering machine, fax machine, speaker
phone, base station of cordless phone
Speech
circuit
Voice
switch
Audio
amplifier
Clock
Data
Reset
DTMF
Serial
bus
MCU
Tone
ringer
Class
14602
Ordering Information
Extended Type Number
U3900BM-AFN
U3900BM-AFNG3
Package
SSO44
SSO44
Remarks
Taped and reeled
Rev. A2, 25-Aug-98
1 (34)
Target Specification
TEMIC [ TEMIC SEMICONDUCTORS ]
