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FEATURES
§ Automatically restarts microprocessor after
power failure
§ Maintains reset for 350 ms after V
CC
returns
to an in-tolerance condition
§ Accurate 5%, 10% or 15% microprocessor 5V
power supply monitoring
§ Reduces need for discrete components
§ Precision temperature-compensated voltage
reference and voltage sensor
§ Low-cost TO-92 package or surface mount
SOT-223 package
§ Internal 5 kW pull-up resistor
§ Compatible with Motorola 68XXX series and
HC16 Microprocessors
§ Operating temperature of -40°C to +85°C
PIN ASSIGNMENT
PIN DESCRIPTION
PIN 1 GROUND
PIN 2 RESET
PIN 3 V
CC
PIN 4 GROUND (SOT-223 ONLY)
DESCRIPTION
The DS1233D EconoReset uses a precision temperature-compensated reference and comparator circuit to
monitor the status of the power supply (V
CC
). When an out-of-tolerance condition is detected, an internal
power-fail signal is generated which forces reset to the active state. When V
CC
returns to an in-tolerance
condition, the reset signal is kept in the active state for approximately 350 ms to allow the power supply
and processor to stabilize.
OPERATION - POWER MONITOR
The DS1233D provides the functions of detecting out-of-tolerance power supply conditions and warning
a processor-based system of impending power failure. When V
CC
is detected as out of tolerance as
defined by the tolerance of the part selected, the
RST signal is asserted. On power-up, RST is kept active
for approximately 350 ms after the power supply has reached the selected tolerance. This allows the
power supply and microprocessor to stabilize before
RST is released.
DS1233D
5V EconoReset
www.maxim-ic.com
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1 2 3
BOTTOM VIEW
TO-92 PACKAGE
See Mech.
Drawings Section
On Website
2
4
TOP VIEW
SOT-23 PACKAGE
See Mech.
Drawings Section
On Website
1
DALLAS
DS1233
Econo
Reset
