General Description
The MAX6826–MAX6831 are ultra-low-voltage micro-
processor (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 VCC down to +1.0V.
A variety of preprogrammed reset threshold voltages
are available (see the 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.
________________________Applications
Features
Monitor Primary VCC Supplies from +1.8V
to +5.0V and Secondary VCC2 Supplies
from +0.9V to +2.5V
User Adjustable RESET IN Down to +0.63V
(MAX6826/MAX6827/MAX6828)
140ms (min) Reset Timeout Delay
1.6s Watchdog Timeout Period
Manual Reset Input
Three Reset Output Options
Push-Pull RESET
Push-Pull RESET
Open-Drain RESET
Guaranteed Reset Valid Down to VCC = +1.0V
Immune to Short Negative VCC Transients
No External Components
Small 6-pin SOT23 Packages
MAX6826
–MAX6831
Dual Ultra-Low-Voltage SOT23 P Supervisors
with Manual Reset and Watchdog Timer
________________________________________________________________ Maxim Integrated Products
1
GND
WDI
MR
16
VCC
5
RESET IN/VCC2
RESET(RESET)
(RESET) MAX6827/MAX6830 ONLY
RESET IN FOR MAX6826/MAX6827/MAX6828 ONLY
VCC2 FOR MAX6829/MAX6830/MAX6831 ONLY
MAX6826–
MAX6831
SOT23-6
TOP VIEW
2
34
Pin Configuration
19-1867; Rev 2; 12/05
Ordering Information
Standard Versions Table*
Insert the desired suffix letter (from Standard Versions table) into
the blanks to complete the part number.
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing “-T” with “+T” when ordering.
PART
TEMP RANGE
PIN-PACKAGE
MAX6826_UT-T
-40°C to +125°C
6 SOT23-6
MAX6827_UT-T
-40°C to +125°C
6 SOT23-6
MAX6828_UT-T
-40°C to +125°C
6 SOT23-6
MAX6829_ _UT-T
-40°C to +125°C
6 SOT23-6
MAX6830_ _UT-T
-40°C to +125°C
6 SOT23-6
MAX6831_ _UT-T
-40°C to +125°C
6 SOT23-6
MAX6826/MAX6827/MAX6828
L
S
R
Z
V
*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.
Portable/Battery-
Powered Equipment
Embedded Controllers
Intelligent Instruments
Automotive Systems
Critical P Monitoring
Multivoltage Systems
Typical Operating Circuit, Threshold Suffix Guide, and
Selector Guide appear at end of data sheet.
Standard Versions Table continued at end of data sheet.
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.