Philips Semiconductors
3-pin ultra-low power SC70/SOT
microprocessor reset circuit
Product data
MAX632x/MAX634x
DESCRIPTION
The MAX6326/MAX6327//MAX6328/MAX6346/MAX6347/MAX6348
microprocessor (µP) reset circuits monitor power supplies in µP and
digital systems. These devices eliminate external components and
adjustments while providing excellent circuit reliability and low cost
solution. They are used to monitor 2.5 V, 3 V, 3.3 V and 5 V power
supplies.
They assert a reset signal when the VDD supply voltage falls below a
preset reset threshold voltage. The reset signal remains asserted for
at least 100 ms after the VDD rises above the reset threshold. The
reset threshold are factory trimmable from 2.2 V to 4.63 V in
approximately 100 mV increments. All these parts are guaranteed to
assert a reset for VDD down to 1 V. They have excellent immunity to
fast transients on VDD.
The devices vary in their output configuration. The
MAX6326/MAX6346 have push-pull, active-LOW reset output; while
the MAX6328/MAX6348 have open drain, active-LOW reset output.
The MAX6327/MAX6347 have push-pull, active HIGH reset output.
The lower threshold MAX6326/MAX6327/MAX6328 have ultra-low
supply current of typically 0.5 µA making them ideal for battery
powered applications. All six devices are available in both the 3-pin
SOT23 and SC70 packages.
FEATURES
• Ultra-low 1 µA (max) supply current
• Precision monitoring of 2.5 V, 3 V, 3.3 V, and 5 V power supply
voltages
• Reset thresholds available from 2.2 V to 4.63 V
• Fully specified over temperature –40 °C to +85 °C
• 100 ms (min) power-on-reset delay time
• Power transient immunity
• Available in three versions: Push-Pull RESET, Push-Pull RESET,
and Open-Drain RESET
• Pin compatible with MAX803/MAX809/MAX810
• Small, low cost, 3-pin SC70/SOT23 packages
APPLICATIONS
• Computers and controllers
• Power monitoring
• Portable/battery powered equipment
• Industrial equipment
SIMPLIFIED SYSTEM DIAGRAM
VDD
VDD
RESET
MAX6328/
MAX6348
RPU
VDD
RESET
MOTOROLA
68HCXX
GND
GND
SL01835
Figure 1. MAX6328/6348 simplified system diagram.
2003 Aug 05
2