Document
MAX6715A–MAX6729A/ MAX6797A
Dual/Triple, Ultra-Low-Voltage, SOT23 μP Supervisory Circuits
General Description
The MAX6715A–MAX6729A/MAX6797A are ultra-lowvoltage microprocessor (μP) supervisory circuits designed to monitor two or three system power-supply voltages. These devices assert a system 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 significantly improve system reliability and reduce size compared 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 the 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/output features are available (see the Selector Guide). Select reset timeout periods from 1.1ms to 1120ms (min) (see the Reset Timeout Period Suffix Guide). The MAX6715A–MAX6729A/MAX6797A are available in small 5-, 6-, and 8-pin SOT23 packages and operate over the -40°C to +125°C temperature range.
Applications
●● Multivoltage Systems
●● Telecom/Networking Equipment
●● Computers/Servers
●● Portable/Battery Operated Equipment
●● Industrial Equipment ●● Printers/Fax Machines ●● Set-Top Boxes
Features
●● VCC1 (Primary Supply) Reset Threshold Voltages from 1.58V to 4.63V
●● VCC2 (Secondary Supply) Reset Threshold Voltages from 0.79V to 3.08V
●● Externally Adjustable RSTIN Threshold for Auxiliary/ Triple-Voltage Monitoring (0.62V Internal Reference)
●● Watchdog Timer Option • 35s (min) Long Startup Period • 1.12s (min) Normal Timeout Period
●● Manual-Reset Input Option ●● Power-Fail Input/Power-Fail Output Option
(Push-Pull and Open-Drain Active-Low) ●● Guaranteed Reset Valid Down to VCC1 or
VCC2 = 0.8V ●● Reset Output Logic Options ●● Immune to Short VCC Transients ●● Low Supply Current 14μA (typ) at 3.6V ●● Watchdog Disable Feature ●● Small 5, 6, and 8-Pin SOT23 Packages ●● AEC-Q100 Qualified: MAX6719AUTTWD1/V+T
Ordering Information continued at end of data sheet. Pin Description and Selector Guide appear at end of data sheet.
Typical Operating Circuit
UNREGULATED DC
R1
R2
DC-DC OUT2
IN
CONVERTER OUT1
PUSHBUTTON SWITCH
VCC1
VCC2
MAX6715AMAX6729A/ MAX6797A
RST
RSTIN/PFI
WDI
MR PFO
MAX67_ _
1.8V 0.9V
I/O CORE SUPPLY SUPPLY
RESET I/O µP NMI
19-0536; Rev 6; 7/19
MAX6715A–MAX6729A/ MAX6797A
Dual/Triple, Ultra-Low-Voltage, SOT23 μP Supervisory Circuits
Absolute Maximum Ratings
Terminal Voltage (with respect to GND) VCC1, VCC2.......