19-1867; Rev 1; 1/02
Dual Ultra-Low-Voltage SOT23 碌P Supervisors
with Manual Reset and Watchdog Timer
General Description
The MAX6826鈥揗AX6831 are ultra-low-voltage micro-
processor (碌P) supervisory circuits designed to monitor
two power supplies and have manual reset and watch-
dog input functions. These devices assert a system reset
if any of the monitored supplies fall below the prepro-
grammed thresholds, and maintain reset for a minimum
timeout period after the supplies rise above the threshold.
Microprocessor supervisors significantly improve system
reliability and accuracy compared to separate ICs or dis-
crete components. These devices monitor primary volt-
ages from +1.8V to +5.0V and secondary voltages from
+0.9V to +2.5V. These devices are guaranteed to be in
the correct state for V
CC
down to +1.0V.
A variety of preprogrammed reset threshold voltages
are available (see
Threshold Suffix Guide).
The devices
include manual reset and watchdog inputs. The
MAX6829/MAX6830/MAX6831 provide a factory-
trimmed threshold to monitor a 2nd voltage down to
+0.9V. The MAX6826/MAX6829 have a push-pull
RESET,
the MAX6827/MAX6830 have a push-pull
RESET and the MAX6828/MAX6831 have an open-drain
RESET.
The MAX6826/MAX6827/MAX6828 have an aux-
iliary monitor that allows user adjustable input to monitor
voltages down to +0.6V. See
Selector Guide
for func-
tions available.
Features
o
Monitor Primary V
CC
Supplies from +1.8V
to +5.0V and Secondary V
CC2
Supplies
from +0.9V to +2.5V
o
User Adjustable RESET IN Down to +0.63V
(MAX6826/MAX6827/MAX6828)
o
140ms (min) Reset Timeout Delay
o
1.6s Watchdog Timeout Period
o
Manual Reset Input
o
Three Reset Output Options
Push-Pull
RESET
Push-Pull RESET
Open-Drain
RESET
o
Guaranteed Reset Valid Down to V
CC
= +1.0V
o
Immune to Short Negative V
CC
Transients
o
No External Components
o
Small 6-pin SOT23 Packages
MAX6826鈥揗AX6831
Ordering Information
PART
鈥?/div>
MAX6826_UT-T
MAX6827_UT-T
MAX6828_UT-T
MAX6829_
_UT-T
MAX6830_
_UT-T
MAX6831_
_UT-T
TEMP RANGE
-40擄C to +125擄C
-40擄C to +125擄C
-40擄C to +125擄C
-40擄C to +125擄C
-40擄C to +125擄C
-40擄C to +125擄C
PIN-PACKAGE
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
________________________Applications
Portable/Battery-
Powered Equipment
Embedded Controllers
Intelligent Instruments
Automotive Systems
Critical 碌P Monitoring
Multivoltage Systems
Pin Configuration
TOP VIEW
RESET(RESET)
1
6
V
CC
鈥?/div>
Insert the desired suffix letter (from Standard Versions table) into
the blanks to complete the part number.
Standard Versions Table*
MAX6826/MAX6827/MAX6828
L
S
5
RESET IN/V
CC2
GND
2
MAX6826鈥?/div>
MAX6831
R
Z
V
MR
3
4
WDI
SOT23-6
(RESET) MAX6827/MAX6830 ONLY
RESET IN FOR MAX6826/MAX6827/MAX6828 ONLY
V
CC2
FOR MAX6829/MAX6830/MAX6831 ONLY
*Samples are typically available for standard versions only.
The MAX6826/MAX6827/MAX6828 require a 2.5k minimum
order increment for all versions. Contact factory for availability.
Typical Operating Circuit appears at end of data sheet.
Threshold Suffix Guide appears at end of data sheet.
Standard Versions Table continued at end of data sheet.
Selector Guide appears at end of data sheet.
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________________________________________________________________
Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim鈥檚 website at www.maxim-ic.com.
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