© Semiconductor Components Industries, LLC, 2011
November, 2011 − Rev. 5
1 Publication Order Number:
CAT1640/D
CAT1640, CAT1641
Supervisory Circuits with
I
2
C Serial 64K CMOS
EEPROM
Description
The CAT1640 and CAT1641 are complete memory and supervisory
solutions for microcontroller−based systems. A 64 kbit 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 400 kHz I
2
C bus.
The CAT1640 provides a precision V
CC
sense circuit and drives an
open drain output, RESET low whenever V
CC
falls below the reset
threshold voltage.
The CAT1641 provides a precision VCC sense circuit that drives an
open drain output, RESET high whenever V
CC
falls below the reset
threshold voltage.
The power supply monitor and reset circuit protect memory and
system controllers during power up/down and against brownout
conditions. Five reset threshold voltages support 5 V, 3.3 V and 3 V
systems. If power supply voltages are out of tolerance reset signals
become 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 CAT1640/41 memory features a 64−byte page. In addition,
hardware data protection is provided by a V
CC
sense circuit that
prevents writes to memory whenever V
CC falls below the reset
threshold or until V
CC
reaches the reset threshold during power up.
Available packages include an 8−pin DIP, SOIC, TSSOP and
4.9 x 3 mm TDFN.
Features
• Precision Power Supply Voltage Monitor
♦ 5 V, 3.3 V and 3 V Systems
S +5.0 V (±5%, ±10%)
S +3.3 V (±5%, ±10%)
S +3.0 V (±10%)
• Active Low Reset, CAT1640
• Active High Reset, CAT1641
• Valid Reset Guaranteed at V
CC
= 1 V
• 400 kHz I
2
C Bus
• 3.0 V to 5.5 V Operation
• Low Power CMOS Technology
• 64−Byte Page Write Buffer
• 1,000,000 Program/Erase Cycles
• 100 Year Data Retention
• 8−pin DIP, SOIC, TSSOP and TDFN Packages
• Industrial Temperature Range
• These Devices are Pb−Free, Halogen Free/BFR Free
and are RoHS Compliant
ORDERING INFORMATION
http://onsemi.com
PDIP−8
CASE 646AA
SOIC−8
CASE 751BD
TSSOP−8
CASE 948S
TDFN−8
CASE 511AM
For Ordering Information details, see page 13.
