AS2591 Datasheet, PDF (1/10 Pages) ams AG – 16-Digit LCD Driver CMOS Integrated Circuit

Preliminary
AS2591
Austria Mikro Systeme International AG
16-Digit LCD Driver
CMOS Integrated Circuit
Key Features
q 16-digit LCD driver on a 44 pin CMOS chip
q Operating voltage range: 3.2 to 4.8V
q Low power consumption: max. 150 µA
q Driving 7-segment displays with up to 16 digits and
12 symbols
q Option for 12 digits
q Buffer for 32 digits
q 4 backplanes
q 2-wire interface
q On chip timer for showing elapsed time
q Contrast adjustable
q On chip oscillator using 32.768 kHz crystal
q Compatible with AS2525
Block Diagramme
V_DD
BACKPLANE
POR
COUNTER
DI
SCLK
CS
SERIAL
I/F
7-
SEGMENT
DECODER
DATA
COMMAND ^ADDRESS
DECODER CONTROL
DIGIT
MEMORY
32 DIGITS
32.768 kHz
OSC
ELAPSE
TIME
COUNTER
General Description
The AS2591 is a CMOS integrated circuit for driving a
liquid crystal display intended for use in telephones.
The driver can be used with 12- or 16-digit LCDs.
The 2-wire serial interface is compatible with the
AS2525, single-chip handsfree telephone circuit.
The device is designed for LCDs with 4 backplanes
and 24 or 31 segments providing 12 or 16 7-segment
digits and 12 symbols.
The AS2591 also includes a timer for showing
elapsed time in minutes and seconds.
The contrast can be adjusted through the serial
interface.
Package
Available in 44 pin TQFP.
4
COM1-4
16
S1_n
16
S2_n
LCD
V_LCD
CONTRAST
VOLTAGE
CONTROL
TIMER
AS2591
Figure 1: Block diagram
Rev. 1.0
Page 1
May 1999