Microprocessor
Supervisory Circuit
ADM1232A
Rev. A
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FEATURES
Precision 5 V voltage monitor with 5% or 10% tolerance options
Adjustable
STROBE
monitor with 150 ms, 600 ms, or 1.2 sec
options
Fast (20 ns)
STROBE
pulse width
No external components required
Packaged in 8-Lead SOIC
Specified from −40°C to +85°C
APPLICATIONS
Microprocessor systems
Portable equipment
Computers
Controllers
Intelligent instruments
Automotive systems
Protection against damage caused by microprocessor failure
FUNCTIONAL BLOCK DIAGRAM
V
CC
OLERANCE
PB RESET
TD
GND
5%/10%
TOLERANCE
SELECT
DEBOUNCE
VREF
RESET
GENERATOR
WATCHDOG
TIMER
WATCHDOG
TIMEBASE
SELECT
RESET
RESET
STROBE
ADM1232A
0061-001
Figure 1.
GENERAL DESCRIPTION
The ADM1232A is pin-compatible to the MAX1232, DS1232LP,
and DS1232. The ADM1232A can detect strobe pulse widths as
narrow as 20 ns, making it compatible with high speed
microprocessors. The Analog Devices, Inc., ADM1232A is a
microprocessor monitoring circuit that monitors micro-
processor supply voltage. It can also detect if a microprocessor
has locked up or an external interrupt has been issued. The
ADM1232A is available in an 8-lead narrow body SOIC and is
specified over the −40°C to +85°C temperature range.
MICROPROCESSOR
GND TD TOLERANCE
RESET
STROBE
RESET
I/O
ADM1232A
5
5
10kΩ
00061-002
Figure 2. Typical Supply Monitoring Application
