H
CAT1640, CAT1641
EE
GEN FR
ALO
Supervisory Circuits with I2C Serial 64K CMOS EEPROM
LE
A D F R E ETM
FEATURES
s 3.0V to 5.5V operation
s Precision power supply voltage monitor
s Low power CMOS technology
— 5V, 3.3V and 3V systems
s 64-Byte page write buffer
- +5.0V (+/- 5%, +/- 10%)
- +3.3V (+/- 5%, +/- 10%)
- +3.0V (+/- 10%)
s 1,000,000 Program/Erase cycles
s 100 year data retention
s Active low reset, CAT1640
s 8-pin DIP, SOIC, TSSOP and TDFN packages
s Active high reset, CAT1641
s Industrial temperature range
s Valid reset guaranteed at VCC=1V
s 400kHz I2C bus
DESCRIPTION
The CAT1640 and CAT1641 are complete memory and
supervisory solutions for microcontroller-based systems.
A 64kbit serial EEPROM memory and a system power
supervisor with brown-out protection are integrated
together in low power CMOS technology. Memory
interface is via a 400kHz I2C bus.
active, preventing the system microcontroller, ASIC or
peripherals from operating. Reset signals become inactive
typically 200 ms after the supply voltage exceeds the reset
threshold level. With both active high and low reset options,
interface to microcontrollers and other ICs is simple. In
addition, the RESET (CAT1640) pin can be used as an
input for push-button manual reset capability.
The CAT1640 provides a precision VCC sense circuit
and drives an open drain output, RESET low whenever The CAT1640/41 memory features a 64-byte page. In
addition, hardware data protection is provided by a VCC
VCC falls below the reset threshold voltage.
sense circuit that prevents writes to memory whenever VCC
The CAT1641 provides a precision VCC sense circuit falls below the reset threshold or until VCC reaches the reset
that drives an open drain output, RESET high whenever threshold during power up.
VCC falls below the reset threshold voltage.
Available packages include an 8-pin DIP, SOIC, TSSOP
The power supply monitor and reset circuit protect and 4.9 x 3mm TDFN.
memory and system controllers during power up/down
and against brownout conditions. Five reset threshold
voltages support 5V, 3.3V and 3V systems. If power
supply voltages are out of tolerance reset signals become
PIN CONFIGURATION
PDIP (P, L) SOIC (J, W)
8 VCC
7 RESET
A0 1
A2 3
6 SCL
VSS 4
A0 1
A1 2
CAT1641
A0
1
8
VCC
A1
2
7
RESET
A2 3
6 SCL
A2
3
6
SCL
VSS 4
5 SDA
VSS
4
5
SDA
8 VCC
CAT1640
8 VCC
7 RESET
5 SDA
A0 1
A1 2
TDFN PACKAGE: 4.9MM X 3MM
(RD2, ZD2)
TSSOP (U, Y)
A0 1
8
VCC
7 RESET
A1 2
7
RESET
6
SCL
5
SDA
A1 2
CAT1640
CAT1641
8 VCC
7 RESET
A0
1
A1
2
A2 3
6 SCL
A2 3
6 SCL
A2
3
VSS 4
5 SDA
VSS 4
5 SDA
VSS
4
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
CAT1640
CAT1641
Doc. No. 25082, Rev. 00
