AS2533 Datasheet, PDF (1/25 Pages) ams AG – Multi-Standard CMOS Single Chip Telephone IC with Dual Soft Clipping

Data Sheet
AS2533...6
Multi-Standard CMOS Single Chip
®
Telephone IC with Dual Soft Clipping
Austria Mikro Systeme International AG
General Description
Key Features
The AS253x is a CMOS integrated circuit that contains
u Line/speech circuit, LD/MF repertory dialler and
tone ringer on one 28 pin CMOS chip
all the functions needed to form a high performance
electronic telephone.
u Operating range from 13 to 100 mA (down to 5 mA
with reduced performance)
u Soft clipping to avoid harsh distortion
u Volume control of receive signal
The device incorporates LD/MF repertory dialling, melody
generation, ring frequency discrimination and a high
quality line/speech circuit.
u Line loss compensation selectable by pin option
u Low noise (max. - 72 dBmp)
u Real or complex impedance
u NET 4 compatible
u LD/MF switchable dialling
u Pacifier tone during programming
A RAM is on chip for a 31 digit last number redial and
memories (not AS2534) each containing up to 21 digits/
data. The sliding cursor procedure makes the LNR
function easy to use under various PABX systems. Also
centrex keys (not AS2535) are provided.
u 31 digit last number redial
u Repertory memories (not AS2534), 4 direct/10
indirect (AS2533/6), 12 direct (AS2535)
u Repeat dialling by busy or engaged (not AS2535)
The device incorporate a volume control for the earpiece.
The volume can be controlled by the VOL key (+ 5.4 dB)
or by the –/+ keys (+8.1 dB/-5.4 dB in 5 steps).
u Sliding cursor protocol with comparison
u Pause key for access pause or wait function
u 3 flash keys, 100 ms, 280 ms and 375/600 ms
u On chip MF filter (CEPT CS 203 compatible)
The versatility of the circuit is provided by pin options
and a few external components. This allows easy
adaptation to different PTT requirements.
u Ring frequency discrimination
u 3-tone melody generator
Package
Block Diagramme
Available in 28 pin SOIC or DIP.
La
Z2
ZBAL
Z1
Lb
LI
CI
LS
RI
STB
AGND
LED
CS
RO
LINE ADAPTATION
POWER EXTRACTION
DC MASK
LINE
CURRENT
SENSE
VDD
VDD
SOFT CLIP
AGC
M2
Vss
M1
AS253x
MO
MELODY
SEQUENCER
R4
TONE
MUTE
GENERATOR
RAM
R3
FCI
RING
FREQUENCY
DISCRIMINATION
CONTROL
LOGIC
OSC
DIALLER
R2
R1
HS/DP
LLC
OSC
MFL
3.58
MHz
MODE ^{C1 C2 C3 C4}
AGND
LLC Hi
LLC Lo
LLC Off
KEY
PAD
Rev. 7
1
July 1998