Data Sheet
Rev. 3 1
AS2578 /B
March 1997
TELEPHONE CONTROLLER WITH
13 MEMORIES AND 2-WIRE BUS
Key Features
a75 Low operating voltage
a75 Low current consumption, standby ≤ 0.1 µA
a75 Oscillator using Xtal or ceramic resonator (3.58 MHz)
a75 Serial interface to external EEPROM
a75 Consistent, simple and usable procedures
a75 The settings are programmed via the keyboard and
stored in EEPROM or set by pin options
Dialler:
a75 Data protection with 20 digit FIFO
a75 Sliding cursor protocol with comparison
a75 Automatic pause generation
a75 Temporary MF select via keyboard
a75 30 digit LNR (Last Number Redial)
a75 13 x 20 digit memory (RAM) on chip
Tone Ringer:
a75 Ring frequency discrimination
a75 3 tone melody with 4 different repetition rates
a75 Volume of melodies can be set in 4 steps
Block Diagramme
General Description
The AS2578 /B are a versatile repertory LD/MF diallers
with a melody generator, a ring frequency discriminator
and a 2-wire interface to EEPROM. Together with the
AS2520/1, the AS2578 /B form a coherent basis for a
fully electronic telephone with a wide range of options.
The AS2578 /B are especially designed to adapt to
different PTT specifications. A RAM is on chip for last
number redial, 3 direct dial and 10 numbers with
abbreviated dialling. To allow easy use under a PABX,
the device incorporates automatic pause insertion and
sliding cursor procedure as selectable options (AS2578)
or centrex keys (AS2578B). The device can be used with
or without EEPROM as appropriate. When an EEPROM
is connected, all RAM content is stored in the EEPROM
by power loss.
The circuit provides the possibility to set different modes
of operation (LM codes) via the keyboard or via pin
options, e.g. default signalling mode, automatic pause
insertion, flash or ground loop and settings of volume
and melodies.
Austria Mikro Systeme International
KEYSCAN
HOOK
STATE
CONTROL
DIAL
DTMF
MELODY
SERIAL
INTERFACE
RING
FREQUENCY
DETECTOR
POR
OSCILLATOR
REDIAL
13 X 20
1 X 30
RAM
FIFO
*
0
87
#
9
2
54
1 3
6
R
MUTE
SET
LNR
3.58 MHz
DP
GL
MUTE
SCL
SDA
FCI
MF
MO
MASK
HS
CE
MODE
AP (AS2578 only)
MV
RR
AS2578 /B
Vss VDD
MEM
M1
M2
M3
D
C
B
A
(AS2578B)
Package
Available in 28 pin DIP and PLCC.
