19-2523; Rev 0; 7/02
Microprocessor Supervisory Reset Circuits
with Edge-Triggered, One-Shot Manual Reset
General Description
Features
The MAX6467/MAX6468 microprocessor (µP) supervi-
sory circuits monitor single power-supply voltages from
+1.8V to +5.0V and assert a reset if the supply voltage
drops below its preset threshold. An edge-triggered,
one-shot manual reset function ensures that the µP
enters the reset mode for a fixed timeout period only,
even in the event of a continuously asserted manual
reset. The MAX6467/MAX6468 significantly improve
system reliability compared to traditional manual reset
supervisory circuits.
ꢀ Precision Factory-Set Reset Threshold Voltages
for +5.0V, +3.3V, +3.0V, +2.5V, and +1.8V Supplies
ꢀ Edge-Triggered Manual Reset Input with One-
Shot Pulsed Reset Output
ꢀ Two Reset Timeout Period Options (150ms or
1200ms min)
ꢀ Immune to Short Voltage Transients
ꢀ Low Supply Current (3µA at V
= +1.8V)
CC
A variety of factory-trimmed threshold options accommo-
date different supply voltages and tolerances, eliminating
external components. The factory-set thresholds range
from +1.575V to +4.625V to monitor +5.0V, +3.3V, +3.0V,
+2.5V, and +1.8V supplies with various tolerances. Reset
timeout periods of 150ms (min) and 1200ms (min) are
available to accommodate different µP platforms.
ꢀ RESET Valid to V
= +1V
CC
ꢀ Active-Low Open-Drain and Push-Pull RESET
Output Options
ꢀ -40°C to +125°C Operating Temperature Range
ꢀ Small 4-Pin SC70 and SOT143 Packages
ꢀ No External Components Required
A single, active-low RESET output asserts when V
CC
drops below its threshold or if the edge-triggered MR
asserts low. RESET remains low for the reset timeout
ꢀ Pin Compatible with MAX811, MAX6315,
period after V
rises above its threshold and for a fixed,
CC
MAX6384, and MAX6386
one-shot timeout period after a manual reset input falling
edge. RESET remains valid as long as V remains
CC
Ordering Information
above +1V. Open-drain (MAX6467) and push-pull
(MAX6468) output options provide additional flexibility in
the system design.
PART
MAX6467XS_ _D_-T -40°C to +125°C
MAX6467US_ _D_-T -40°C to +125°C
MAX6468XS_ _D_-T -40°C to +125°C
MAX6468US_ _D_-T -40°C to +125°C
TEMP RANGE
PIN-PACKAGE
4 SC70-4
4 SOT143-4
4 SC70-4
The MAX6467/MAX6468 are offered in the space-saving
4-pin SOT143 package and the ultra-small 4-pin SC70
package and are specified over the automotive (-40°C to
+125°C) temperature range.
4 SOT143-4
Note: Insert reset threshold suffix (see Reset Threshold table)
after XS or US. Insert reset timeout delay (see Reset Timeout
Delay table) after D to complete the part number. Sample stock
is generally held on standard versions only (see Standard
Versions table). Standard versions have an order increment
requirement of 2500 pieces. Nonstandard versions have an
order increment requirement of 10,000 pieces. Contact factory
for availability.
Applications
Cell Phones/PDAs
Embedded Control Systems
Industrial Equipment
Automotive Products
Portable/Battery-Powered Equipment
Medical Devices
Pin Configurations
TOP VIEW
DSL Modems
GND
1
2
4
3
V
CC
MP3 Players
MAX6467XS
MAX6468XS
GPS Systems
MR
RESET
Digital Cameras
SC70
Pin Configurations continued at end of data sheet.
Typical Operating Circuit appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.