U4055B1
Model | U4055B1 |
Description | Low-Voltage Electronic Speech Circuit with Dialer Interface |
PDF file | Total 10 pages (File size: 152K) |
Chip Manufacturer | TEMIC |
U4055B/U4055B1
Low-Voltage Electronic Speech Circuit with Dialer Interface
Description
The U4055B electronic speech circuit is a linear
integrated circuit for use in telephone and other line fed
terminal equipment. It replaces the common speech
circuit with carbon microphone, hybrid transformer,
sidetone equivalent and ear protection rectifiers. A
low-cost electrodynamic transducer is used as the
earphone. It contains all components necessary for
amplification of signals and adaption to the line.
Features
D
An electronic circuit replaces the microphone hybrid
transformer
D
Symmetrical input for dynamic or piezo microphone
D
High performance through the use of dynamic
transducers as the earphone (non-linear distortion
2 %)
D
D
D
D
DTMF interface with muting
Supply voltage for dialer
High range of line feeding current
Input resistance independent of line current and
sidetone suppression circuit.
x
D
Automatic line loss compensation
D
Built-in ear protection by earphone voltage limiter
D
Operation possible from 8 mA
U4055B1:
High level mute;
U4055B:
Low level mute
Figure 1. Block diagram and pin connection
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96
1 (10)
Preliminary Information