19-2325; Rev 3; 6/03
Dual/Triple Ultra-Low-Voltage SOT23 µP
The MAX6715–MAX6729 are ultra-low-voltage microproces-
sor (µP) supervisory circuits designed to monitor two or three
system power-supply voltages. These devices assert a sys-
tem reset if any monitored supply falls below its factory-
trimmed or adjustable threshold and maintain reset for a
minimum timeout period after all supplies rise above their
thresholds. The integrated dual/triple supervisory circuits sig-
nificantly improve system reliability and reduce size com-
pared to separate ICs or discrete components.
These devices monitor primary supply voltages (VCC1) from
1.8V to 5.0V and secondary supply voltages (VCC2) from
0.9V to 3.3V with factory-trimmed reset threshold voltage
options (see Reset Voltage Threshold Suffix Guide). An
externally adjustable RSTIN input option allows customers to
monitor a third supply voltage down to 0.62V. These devices
are guaranteed to be in the correct reset output logic state
when either VCC1 or VCC2 remains greater than 0.8V.
A variety of push-pull or open-drain reset outputs along with
watchdog input, manual reset input, and power-fail input/out-
put features are available (see Selector Guide). Select reset
timeout periods from 1.1ms to 1120ms (min) (see Reset
Timeout Period Suffix Guide). The MAX6715–MAX6729 are
available in small 5, 6, and 8-pin SOT23 packages and oper-
ate over the -40°C to +85°C temperature range.
Typical Operating Circuit
o VCC1 (primary supply) Reset Threshold Voltages
from 1.58V to 4.63V
o VCC2 (secondary supply) Reset Threshold
Voltages from 0.79V to 3.08V
o Externally Adjustable RSTIN Threshold for
(0.62V internal reference)
o Watchdog Timer Option
35s (min) Long Startup Period
1.12s (min) Normal Timeout Period
o Manual Reset Input Option
o Power-Fail Input/Power-Fail Output Option
(Push-Pull and Open-Drain Active-Low)
o Guaranteed Reset Valid Down to VCC1 or
VCC2 = 0.8V
o Reset Output Logic Options
o Immune to Short VCC Transients
o Low Supply Current 14µA (typ) at 3.6V
o Small 5, 6, and 8-Pin SOT23 Packages
TEMP RANGE PIN-PACKAGE
MAX6715UT_ _D_ -T -40°C to +85°C 6 SOT23-6
MAX6716UT_ _D_ -T -40°C to +85°C 6 SOT23-6
MAX6717UK_ _D_ -T -40°C to +85°C 5 SOT23-5
MAX6718UK_ _D_ -T -40°C to +85°C 5 SOT23-5
MAX6719UT_ _D_ -T -40°C to +85°C 6 SOT23-6
MAX6720UT_ _D_ -T -40°C to +85°C 6 SOT23-6
Note: The first “_ _” are placeholders for the threshold voltage
levels of the devices. Desired threshold levels are set by the part
number suffix found in the Reset Voltage Threshold Suffix Guide.
The “_” after the D is a placeholder for the reset timeout delay
time. Desired delay time is set using the timeout period suffix
found in the Reset Timeout Period Suffix Guide. For example the
MAX6716UTLTD3-T is a dual-voltage supervisor VTH1 = 4.625V,
VTH2 = 3.075V, and 210ms (typ) timeout period.
Ordering Information continued at end of data sheet.
Pin Configurations appear at end of data sheet.
Selector Guide appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products 1
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.