AS2533_1 Datasheet, PDF (1/25 Pages) ams AG – Multi-Standard CMOS Telephone IC for Basic Telephones

Multi-Standard CMOS Telephone IC
for Basic Telephones
AS2533-36
austriamicrosystems
DATA SHEET
General Description
The AS253x is a CMOS integrated circuit that contains all
the functions needed to build a high performance electronic
telephone set with basic features.
The AS253x incorporates a line interface, a speech circuit,
a dialler and ringer. It is a real single-chip / single-die IC
with 28 pins. It allows either package mounting or chip-on-
board mounting.
The device is available in 4 versions (pin-compatible) with
different features ranging from LNR only (last number
redial) to 4 direct (one-touch) memories and 10 indirect
(two-touch) memories. The sliding cursor procedure makes
the LNR function easy to use under various PABX systems.
The versatility of the circuit is provided by pin options and a
few external components. This allows fast time-to-market
and easy adaptation to different PTT requirements. A
unique EMI performance has been achieved due to the
consequent use of CMOS amplifiers.
Key Features
Line Interface and Speech Circuit
- Electronic Rx volume control
- Electronic microphone mute
- Microphone amplifier with symmetrical input
Block Diagram
- Rx and Tx soft clipping to avoid harsh distortion
- Real or complex impedance (EU compliant)
- Stabilized supply for dialler and peripherals
- Automatic line loss compensation
- Operating range from 13 to 100 mA (down to 5 mA with
reduced performance)
- Unique EMI performance (EU compliant)
Dialler
- LD/MF dialing and mixed-mode dialing
- 31 digit last number redial (LNR)
- 4 direct/10 indirect (AS2533/36), 12 direct (AS2535)
- Repeat dialing by busy or engaged (not AS2535)
- Confidence tone during memory programming and mute
- Notepad memory function
- Pause key for access pause or wait function
- 3 flash timings, 100 ms, 280 ms and 375/600 ms
- Sliding cursor protocol with comparison
Ringer
- Ring frequency discrimination
- 3-tone melody generator
- Ring melody selection via keyboard
- Ring volume selection via keyboard
- Version available with fixed ring melody and ring volume
Package
- SOIC 28 or DIE
Revision 8.8
Figure 1 Block Diagram
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