Advanced
CAT24C323(32K), CAT24C643 (64K)
Supervisory Circuits with I2C Serial CMOS E2PROM, Precision Reset Controller and Watchdog Timer
FEATURES
s
Watchdog Timer Input (WDI)
s
Programmable Reset Threshold
s
400 KHz I2C Bus Compatible
s
2.7 to 6 Volt Operation
s
Low Power CMOS Technology
s
32 - Byte Page Write Buffer
s
Built-in inadvertent write protection
s
Active High or Low Reset Outputs
— Precision Power Supply Voltage Monitoring
— 5V, 3.3V and 3V options
s
1,000,000 Program/Erase Cycles
s
100 Year Data Retention
s
8-Pin DIP or 8-Pin SOIC
s
Commercial, Industrial and Automotive
— V
CC
Lock Out
Temperature Ranges
DESCRIPTION
The CAT24C323/643 is a single chip solution to three
popular functions of EEPROM memory, precision reset
controller and watchdog timer. The 24C323(32K) and
24C643 (64K) feature a I
2
C Serial CMOS EEPROM
Catalyst advanced CMOS technology substantially re-
duces device power requirements. The 24C323/643
features a 32-byte page and is available in 8-pin DIP or
8-pin SOIC packages.
The reset function of the 24C323/643 protects the sys-
tem during brown out and power up/down conditions.
During system failure the watchdog timer feature pro-
tects the microcontroller with a reset signal. 24C323
features active low reset on pin 2 and active high reset
on pin 7. 24C323/643 features watchdog timer on the
WDI input pin (pin 1).
PIN CONFIGURATION
24C323/643*
WDI
RESET
WP
VSS
VCC
RESET
SCL
SDA
BLOCK DIAGRAM
EXTERNAL LOAD
DOUT
ACK
VCC
VSS
WORD ADDRESS
BUFFERS
COLUMN
DECODERS
SENSE AMPS
SHIFT REGISTERS
*All products offered in P and J packages
SDA
START/STOP
LOGIC
PIN FUNCITONS
Pin Name
SDA
RESET/RESET
SCL
Vcc
V
SS
WDI
WP
Function
WP
XDEC
CONTROL
LOGIC
E
2
PROM
Serial Data/Address
Reset I/O
Clock Input
Power Supply
Ground
Watchdog Timer Input
Write Protect
DATA IN STORAGE
HIGH VOLTAGE/
TIMING CONTROL
RESET Controller
WATCHDOG
STATE COUNTERS
SLAVE
ADDRESS
COMPARATORS
SCL
High
Precision
Vcc Monitor
WDI RESET/RESET
© 1998 by Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. 25084-00 12/98
CATALYST [ CATALYST SEMICONDUCTOR ]
