SUMMIT
MICROELECTRONICS, Inc.
SMS2902/SMS2904/SMS2916
Voltage Supervisory Circuit With Watchdog Timer
FEATURES
• Precision Voltage Monitor
– V
CC
Supply Monitor
- Complementary reset outputs for complex
microcontroller systems
- Integrated memory write lockout function
- No external components required
•Watchdog Timer
– 1600 ms, internal
• Two Wire Serial Interface (I
2
C™)
• Extended Programmable Functions
available on SMS24
• High Reliability
– Endurance: 100,000 erase/write cycles
– Data retention: 100 years
• 8-Pin SOIC Packages
OVERVIEW
The SMS29xx is a power supervisory circuit that monitors
V
CC
and will generate complementary reset outputs. The
reset pins also act as I/Os and may be used for signal
conditioning. The SMS29xx also has an on-board watch-
dog timer.
The SMS29xx integrates a nonvolatile serial memory. It
features the industry standard I
2
C serial
interface allowing quick implementation in an end-users’
system.
BLOCK DIAGRAM
VCC
8
SCL
SDA
6
5
NONVOLATILE
MEMORY
ARRAY
WRITE
CONTROL
PROGRAMMABLE
RESET PULSE
GENERATOR
2
RESET#
+
–
VTRIP
RESET
CONTROL
7
WDI#
1
1.26V
WATCHDOG
TIMER
RESET
4
GND
2028 T BD 2.0
SUMMIT MICROELECTRONICS, Inc.
•
300 Orchard City Drive, Suite 131
•
Campbell, CA 95008
•
Telephone 408-378-6461
•
Fax 408-378-6586
•
www.summitmicro.com
© SUMMIT MICROELECTRONICS, Inc. 2000
2028 5.1 8/2/00
Characteristics subject to change without notice
1