AS2590 Datasheet, PDF (1/12 Pages) ams AG – LC DISPLAY DRIVER WITH 18 DIGITS, 6 SYMBOLS AND CLOCK/TIMER

Data Sheet
AS2590
LC DISPLAY DRIVER WITH 18 DIGITS,
®
Austria Mikro Systeme International
6 SYMBOLS AND CLOCK/TIMER
Key Features
u Very low operating current, typ. 30 µA @ 3V
u Low power oscillator using 32.768 kHz Xtal
u 2-wire interface compatible to AS2574B
u 18 digits by 7 segments
u 6 symbols
u 24 hour clock showing hours and minutes
u Timer automatically showing elapsed time in
minutes and seconds after each telephone
conversation
u 33 LCD segment outputs and 4 LCD backplane
outputs
u 4 times multiplex mode with a cycle time of 128 Hz
u Mode select pin for selecting clock function
Package
Available in 48 pin DIP and 52 pin PLCC.
General Description
The AS2590 is an integrated CMOS device for driving a
liquid crystal display intended for use in telephones. The
2-wire serial interface is compatible to the dialler
AS2574B.
The extreme low operating current allows the circuit to
be operational also during on-hook which is necessary
in order to the use of the clock function. In on-hook
condition the circuit can be supplied by a small leakage
current from the telephone line or from a small 3V
battery.
Whether the oscillator shall continue operating or be
stopped during on-hook is determined by the mode pin,
MS.
SPEECH CIRCUIT
KEYBOARD
VDD
DIALLER
CONTROLLER
AS2574A/B
Vss
VDD
V23
MS
V13
X1
VLCD
SDA
SCL
X2
BIAS
Vss
32.768kHz
Rev. 1
1
Dec. 1993