CAT823, CAT824, CAT825
System Supervisory Voltage
Reset with Watchdog and
The CAT823, CAT824, and CAT825 provide basic reset and
monitoring functions for the electronic systems. Each device monitors the
system voltage and maintains a reset output until that voltage reaches
the device’s specified trip value and then maintains the reset output
active condition until the device’s internal timer, after a minimum
timer of 140 ms; to allow the systems power supply to stabilize.
The CAT823 and CAT824 also have a watchdog input which can be
used to monitor a system signal and cause a reset to be issued if the
signal fails to change state prior to a timeout condition.
The CAT823 and CAT825 also provide a manual reset input which
can be used to initiate reset if pulled low. This input can be directly
attached to a push−button or a processor signal.
• Automatically Restarts Microprocessor after Power Failure
• Monitors Pushbutton for External Override
• Accurate Under Voltage System Monitoring
• Brownout Detection System Reset for use with 3.0, 3.3, and 5.0 Volt
• Pin and Function Compatible with the MAX823/24/25 Products
• Operating Range from −40°C to +85°C
• Available in TSOT−23 5−lead and SC−70 Packages
• These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS
• Microprocessor and Microcontroller Based Systems
• Intelligent Instruments
• Control Systems
• Critical mP Monitors
• Portable Equipment
RESET CMOS Push−Pull Active Low Reset Output
MR Manual Reset input – Pulled high Internally by a 52 kW res-
istor designed to be driven low by a mechanical pushbutton,
open drain output or CMOS output.
RESET CMOS Push−Pull Active High Reset Output
WDI Watchdog Timer Input – Designed to be driven by a processor
output or can be disabled by tri−stating or leaving open.
VCC Power Supply
= Specific Device Code
= Date Code
= Pb−Free Package*
(*Note: Microdot may be in either location)
See detailed ordering and shipping information in the package
dimensions section on page 11 of this data sheet.
© Semiconductor Components Industries, LLC, 2012
May, 2012 − Rev. 8
Publication Order Number: