MAX809MEUR Datasheet, PDF (1/8 Pages) Maxim Integrated Products – 3-Pin Microprocessor Reset Circuits

19-0344; Rev 5; 1/01
3-Pin Microprocessor Reset Circuits
General Description
The MAX803/MAX809/MAX810 are microprocessor (µP)
supervisory circuits used to monitor the power supplies
in µP and digital systems. They provide excellent circuit
reliability and low cost by eliminating external compo-
nents and adjustments when used with +5V, +3.3V,
+3.0V, or +2.5V powered circuits.
These circuits perform a single function: they assert a
reset signal whenever the V_CC supply voltage declines
below a preset threshold, keeping it asserted for at
least 140ms after V_CC has risen above the reset thresh-
old. Reset thresholds suitable for operation with a vari-
ety of supply voltages are available.
The MAX803 has an open-drain output stage, while the
MAX809/MAX810 have push-pull outputs. The
MAX803’s open-drain RESET output requires a pull-up
resistor that can be connected to a voltage higher than
V_CC. The MAX803/MAX809 have an active-low RESET
output, while the MAX810 has an active-high RESET
output. The reset comparator is designed to ignore fast
transients on V_CC, and the outputs are guaranteed to
be in the correct logic state for V_CC down to 1V.
Low supply current makes the MAX803/MAX809/
MAX810 ideal for use in portable equipment. The
MAX803 is available in a 3-pin SC70 package, and the
MAX809/MAX810 are available in 3-pin SC70 or SOT23
packages.
Applications
Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment
Automotive
Typical Operating Circuit
V_CC
V_CC
MAX803
MAX809
RESET
V_CC
R_PULL-UP*
µP
RESET
INPUT
GND
GND
*MAX803 ONLY
____________________________Features
o Precision Monitoring of +2.5V, +3V, +3.3V, and
+5V Power-Supply Voltages
o Fully Specified Over Temperature
o Available in Three Output Configurations
Open-Drain RESET Output (MAX803)
Push-Pull RESET Output (MAX809)
Push-Pull RESET Output (MAX810)
o 140ms min Power-On Reset Pulse Width
o 12µA Supply Current
o Guaranteed Reset Valid to V_CC = +1V
o Power Supply Transient Immunity
o No External Components
o 3-Pin SC70 and SOT23 Packages
Ordering Information
PART
TEMP. RANGE PIN-PACKAGE
MAX803_EXR-T
-40°C to +125°C 3 SC70-3
MAX803_EXR-T10 -40°C to +125°C 3 SC70-3
MAX809_EXR-T
-40°C to +125°C 3 SC70-3
MAX809_EXR-T10 -40°C to +125°C 3 SC70-3
MAX809_EUR-T
-40°C to +105°C 3 SOT23-3
MAX809_EUR-T10 -40°C to +105°C 3 SOT23-3
MAX810_EXR-T
-40°C to +125°C 3 SC70-3
MAX810_EXR-T10 -40°C to +125°C 3 SC70-3
MAX810_EUR-T
-40°C to +105°C 3 SOT23-3
MAX810_EUR-T10 -40°C to +105°C 3 SOT23-3
Note: These parts are offered in 2.5k or 10k reels, and must be
ordered in 2.5k or 10k increments. Order MAX803_EXR-T for
2.5k reels and MAX803_EXR-T10 for 10k reels. Insert the
desired suffix letter from the Selector Guide into the blank to
complete the part number. All versions of these products may
not be available at the time of announcement. Contact factory for
availability.
Pin Configuration
TOP VIEW
GND 1
MAX803
MAX809
MAX810
3 VCC
RESET (RESET) 2
( ) ARE FOR MAX810.
SC70-3/SOT23-3
MAX803 AVAILABLE IN SC70-3 ONLY.
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