MAX6721:Dual/Triple Ultra-Low-Voltage SOT23 µP Supervisory Circuits

The MAX6715-MAX6729 are ultra-low-voltage 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 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 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 operate over the -40°C to +85°C temperature range.

Key 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
  • Small 5, 6, and 8-Pin SOT23 Packages
MAX6715, MAX6716, MAX6717, MAX6718, MAX6719, MAX6720, MAX6721, MAX6722, MAX6723, MAX6724, MAX6725, MAX6726, MAX6727, MAX6728, MAX6729: Typical Operating Circuit
MAX6715, MAX6716, MAX6717, MAX6718, MAX6719, MAX6720, MAX6721, MAX6722, MAX6723, MAX6724, MAX6725, MAX6726, MAX6727, MAX6728, MAX6729: Typical Operating Circuit
Applications/Uses
  • Computers/Servers
  • Industrial Equipment
  • Multivoltage Systems
  • Portable Battery-Powered Equipment
  • Printers and Faxes
  • Set-Top Boxes
  • Telecom/Networking Equipment
DataSheet
titleDownload file
MAX6715-MAX6729 Data SheetMAX6715-MAX6729.pdf
Parametrics
Part NumberInterfaceReset Thresh.
(V)
Reset OuttRESETWatchdog FeatureWatchdog TimeoutSupervisor FeaturesReset Thresh. Accur.
(%)
ICC
(µA)
Package/PinsBudgetary
Price
min@ +25°CmaxSee Notes
MAX6715Factory Fixed0 to 1.2
1.2 to 1.8
1.8 to 2.5
2.5 to 3.3
3.3 to 5.5
Active Low
Open Drain
1ms to 15ms
15ms to 85ms
85ms to 300ms
300ms to 1s
>1s
No Watchdog-Manual Reset2.537SOT/6$3.21 @1k
MAX6716Active Low
Push-Pull
No Watchdog-Manual ResetSOT/6$3.21 @1k
MAX6717Active Low
Open Drain
No Watchdog-Manual ResetSOT/5$3.21 @1k
MAX6718Active Low
Push-Pull
No Watchdog-Manual ResetSOT/5$3.21 @1k
MAX6721Active Low
Open Drain
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Manual ResetSOT/6$3.21 @1k
MAX6722Active Low
Push-Pull
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Manual ResetSOT/6$2.85 @1k
MAX6728Active Low
Open Drain
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset Input
Manual Reset
Power Fail Comparator/Low Battery Detect
SOT/8$3.21 @1k
MAX6729Active Low
Push-Pull
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset Input
Manual Reset
Power Fail Comparator/Low Battery Detect
SOT/8$3.21 @1k

Part NumberInterfaceReset Thresh.
(V)
Reset OuttRESETWatchdog FeatureWatchdog TimeoutSupervisor FeaturesReset Thresh. Accur.
(%)
ICC
(µA)
Package/PinsBudgetary
Price
min@ +25°CmaxSee Notes
MAX6719Factory Fixed0 to 1.2
1.2 to 1.8
1.8 to 2.5
2.5 to 3.3
3.3 to 5.5
Active Low
Open Drain
1ms to 15ms
15ms to 85ms
85ms to 300ms
300ms to 1s
>1s
No Watchdog-Adjustable Reset Input
Manual Reset
2.537SOT/6$3.21 @1k
MAX6720Active Low
Push-Pull
No Watchdog-Adjustable Reset Input
Manual Reset
SOT/6
MAX6723Active Low
Open Drain
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset InputSOT/6
MAX6724Active Low
Push-Pull
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset InputSOT/6
MAX6725Active High
Active Low
Open Drain
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset Input
Manual Reset
SOT/8
MAX6726Active High
Active Low
Push-Pull
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset Input
Manual Reset
SOT/8
MAX6727Active Low
Open Drain
Extended Setup Period
Input (WDI)
1s to 2s
>2s
Adjustable Reset Input
Manual Reset
SOT/8
Related Products
  • MAX6708:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6705:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6706:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6703:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6704:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6701:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6702:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6707:Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer
  • MAX6828:Dual, Ultra-Low-Voltage SOT23 µP Supervisors with Manual Reset and Watchdog Timer
  • MAX6831:Dual, Ultra-Low-Voltage SOT23 µP Supervisors with Manual Reset and Watchdog Timer
  • MAX6829:Dual, Ultra-Low-Voltage SOT23 µP Supervisors with Manual Reset and Watchdog Timer
  • MAX6826:Dual, Ultra-Low-Voltage SOT23 µP Supervisors with Manual Reset and Watchdog Timer
  • MAX6827:Dual, Ultra-Low-Voltage SOT23 µP Supervisors with Manual Reset and Watchdog Timer
  • MAX6830:Dual, Ultra-Low-Voltage SOT23 µP Supervisors with Manual Reset and Watchdog Timer
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6721UTLTD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTLTD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTLTD3+TActiveSOT,;6 pin;9 mm²-40°C to +85°CLead Free
MAX6721UTLTD3-TNo Longer AvailableMAX6721UTLTD3+TSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTLTD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTLTD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTLTD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMRD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMRD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMRD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6721UTMRD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMRD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMRD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMSD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMSD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMSD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMSD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMSD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTMSD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRDD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6721UTRDD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRDD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRDD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRDD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRDD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRFD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRFD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRFD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRFD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRFD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6721UTRFD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRHD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRHD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRHD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRHD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRHD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRHD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRVD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRVD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRVD3+TActiveSOT,;6 pin;9 mm²-40°C to +85°CLead Free
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6721UTRVD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRVD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRVD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRVD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRYD1-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRYD2-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRYD3-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRYD4-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRYD5-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6721UTRYD6-TNo Longer AvailableSOT,;6 pin;9 mm²-40°C to +85°CNo
MAX6715-MAX6729.pdf MAX6727
MAX6715-MAX6729.pdf MAX6729
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