19-1568; Rev 0; 10/99
6-Pin µP Reset Circuit with
Power-Fail Comparator
2–MAX6345
General Description
Features
The MAX6342–MAX6345 family of microprocessor (µP)
supervisory circuits monitors power supplies in digital sys-
tems. These devices significantly improve system reliabili-
ty and accuracy compared to separate ICs or discrete
components.
♦ Small 6-Pin SOT23 Package
♦ Precision Factory-Set V Reset Thresholds
CC
Between 2.33V and 4.63V
♦ Guaranteed RESET Valid to V
= +1V
CC
The MAX6342–MAX6345 provide factory-trimmed V
CC
♦ 100ms min Reset Pulse Width
reset threshold voltages from 2.33V to 4.63V and operate
with supply voltages between +1V and +5.5V. A +1.25V
threshold detector allows for a power-fail warning, for low-
battery detection, or for monitoring another power supply.
The MAX6342 contains an MR input and an active-low
push-pull reset. The MAX6343 and MAX6344 are identical
to the MAX6342 except they provide an active-low, open-
drain reset and an active-high, push-pull reset, respective-
ly. The MAX6345 provides a second reset output in place
of the MR input to give it an active-high push-pull reset
and an active-low push-pull reset.
♦ Debounced CMOS-Compatible Manual-Reset
Input
♦ Voltage Monitor for Power-Fail or Low-Battery
Warning
Ordering Information
PART
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
MAX6342_UT-T
MAX6343_UT-T
MAX6344_UT-T
MAX6345_UT-T
All of the devices are packaged in a miniature 6-pin
SOT23.
Note: The MAX6342–MAX6345 are available with factory-set
reset thresholds from 2.33V to 4.63V (see Selector Guides 1, 2).
Insert the letter corresponding to the desired nominal reset
threshold into the blank following the part number. There is a
2500 piece order increment required for the SOT package. SOT
Top Marks table appears at end of data sheet. All versions of
these products may not be available at time of announcement.
Contact factory for availability.
Applications
Portable Computers
Telecom Equipment
Networking Equipment
Portable/Battery-Powered Equipment
Multivoltage Systems
Pin Configurations
Embedded Control Systems
TOP VIEW
Typical Operating Circuit appears at end of data sheet.
Selector Guide 1
RESET THRESHOLD (V)
V
1
2
3
6
5
4
RESET (RESET)
CC
SUFFIX
MAX6342
MAX6343
MAX6344
4.63
4.38
3.08
2.93
2.63
2.33
L
M
T
GND
PFI
MR
PFO
S
R
Z
( ) ARE FOR MAX6344 ONLY.
Pin Configurations continued at end of data sheet.
SOT23-6
Selector Guide 2
PUSH-PULL
RESET OUTPUT
OPEN-DRAIN
RESET OUTPUT
PUSH-PULL RESET
OUTPUT
MANUAL-RESET
INPUT
PART
✔
✔
✔
✔
—
MAX6342
MAX6343
MAX6344
MAX6345
—
—
—
✔
✔
✔
—
—
✔
—
—
________________________________________________________________ Maxim Integrated Products
1
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For small orders, phone 1-800-835-8769.