National Semiconductor | High-performance Analog

 

 LM3724   
5-Pin Microprocessor Reset Circuits 		Click link to Download

Features

  • Precise monitoring of 2.5V, 3.3V, and 5V supply voltages
  • Fully specified over temperature
     Industrial: −40°C to +85°C
     Extended: −40°C to +125°C
  • 100 ms minimum Power-On Reset pulse width, 190 ms typical:
     Active-Low ^RESET Output (LM3722)
     Active-High RESET Output (LM3723)
     Active-Low ^RESET Open Drain Output (LM3724)
  • Guaranteed ^RESET Output valid for VCC ≥ 1V
  • Low Supply Current, 6µA typical
  • Power supply transient immunity
  • Compatible with MAX811/812 applications

    • Description

    The LM3722/LM3723/LM3724 microprocessor supervisory circuits monitor the power supplies in microprocessor and digital systems. They provide a reset to the microprocessor during power-up, power-down, brown-out conditions, and manual reset.

    The LM3722/LM3723/LM3724 asserts a reset signal whenever the supply decreases below the factory-programmed reset threshold. Reset will be asserted for at least 100ms even after VCC rises above the reset threshold.

    The LM3722 has an active-low ^RESET push-pull output. The LM3723 has an active-high RESET push-pull output. The LM3724 has an active-low open-drain ^RESET output.

    Three standard reset voltage options are available, suitable for monitoring 5V, 3.3V, and 2.5V supply voltages. Additional reset voltages are also available; contact National Semiconductor for details.

    With a low supply current of only 6µA, the LM3722/LM3723/LM3724 are ideal for use in portable equipment. The LM3722/LM3723/LM3724 are available in the 5-pin SOT23 package.


    Applications

  • Microprocessor Systems
  • Computers
  • Controllers
  • Intelligent Instruments
  • Portable/Battery-Powered Equipment




    • Typical Application
    click for larger image


    		Block Diagram
    click for larger image



    Typical Performance
    click for larger image


     

    ParametersValues
    Power on Reset Yes
    Watchdog No
    Power Fail Input No
    Manual Reset Yes
    Reset Timeout Period 190 ms
    On/Off Pin Yes
    PowerGood / Error Flag Yes
    Input Min Voltage 1 Volt
    Input Max Voltage 6 Volt
    Output Current 20 mA
    RegType Supervisor
    Temperature Min -40 deg C
    Temperature Max 125 deg C
    Voltage Supervised 2.5 Volt

    Datasheets
    TitleSizeDateOther
    Language
    LM3724 5-Pin Microprocessor Reset Circuits290
    Kbytes    		21-Jul-07   

    Part Number(s)
    (NSID)    		Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM3724EM5-3.08/NOPB


    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    AVNET-EMWorldwide4000
    DIGI-KEYWorldwide1385
    MOUSERWorldwide1350
    NEWARKAmericas661
    RS COMPONENTSWorldwide25
    		$0.95 each at 1K+ pcsreel
    of
    1000
    LM3724EM5-4.63/NOPB


    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    DIGI-KEYWorldwide2383
    MOUSERWorldwide775
    RS COMPONENTSWorldwide65
    		$0.95 each at 1K+ pcsreel
    of
    1000
    LM3724EM5X-4.63/NOPB

    LM3724EM5X-4.63

    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    		$0.95 each at 1K+ pcsreel
    of
    3000
    LM3724IM5-2.32/NOPB


    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide2000
    DIGI-KEYWorldwide2481
    MOUSERWorldwide550
    RS COMPONENTSWorldwide901
    TAYLORAmericas2000
    		$0.80 each at 1K+ pcsreel
    of
    1000
    LM3724IM5-3.08/NOPB


    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide5248
    AVNET-EMWorldwide14000
    DIGI-KEYWorldwide2273
    MOUSERWorldwide651
    NEWARKAmericas772
    RS COMPONENTSWorldwide307
    TAYLORAmericas8248
    		$0.80 each at 1K+ pcsreel
    of
    1000
    LM3724IM5-4.63/NOPB


    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide1000
    AVNET-EMWorldwide1000
    DIGI-KEYWorldwide2414
    MOUSERWorldwide995
    RS COMPONENTSWorldwide6
    TAYLORAmericas1000
    		$0.80 each at 1K+ pcsreel
    of
    1000
    LM3724IM5X-3.08/NOPB

    LM3724IM5X-3.08

    RoHS Status

    SOT-23    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    		$0.80 each at 1K+ pcsreel
    of
    3000

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM3724EM5-2.32
    		NONE
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM3724IM5X-2.32
    		NONE
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009

    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM3724.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM3724 is located at RoHS Status.

    Part Number(s)
    (NSID)    		Weight
    (milligrams)    		TypePinsMSL RatingPeak ReflowRoHS
    Status    		CAD SymbolsModelsPackage
    Marking
    Format
    LM3724EM5-3.08/NOPB

    		14.696
    14.801
    		SOT-2351260DetailDownloadN/A
    		R63B
    XTT
    LM3724EM5-4.63/NOPB

    		14.696
    14.801
    		SOT-2351260DetailDownloadN/A
    		R62B
    XTT
    LM3724EM5X-4.63/NOPB

    LM3724EM5X-4.63
    		14.696
    14.801
    		SOT-2351
    1    		260
    260    		DetailDownloadN/A
    		R62B
    XTT
    LM3724IM5-2.32/NOPB

    		14.696
    14.801
    		SOT-2351260DetailDownloadN/A
    		R50B
    XTT
    LM3724IM5-3.08/NOPB

    		14.696
    14.801
    		SOT-2351260DetailDownloadN/A
    		R53B
    XTT
    LM3724IM5-4.63/NOPB

    		14.696
    14.801
    		SOT-2351260DetailDownloadN/A
    		R55B
    XTT
    LM3724IM5X-3.08/NOPB

    LM3724IM5X-3.08
    		14.696
    14.801
    		SOT-2351
    1    		260
    260    		DetailDownloadN/A
    		R53B
    XTT

    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM3724.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM3724 is located at RoHS Status.

    CAD Symbols and Models
    Download LM3724 CAD Symbols
    		 Models
    N/A


    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM3724EM5-3.08CS065247473430552700011568301341
    LM3724EM5-4.63CS065247473430552700011568301341
    LM3724EM5X-4.63CS065247473430552700011568301341
    LM3724IM5-2.32CS065247473430552700011568301341
    LM3724IM5-3.08CS065247473430552700011568301341
    LM3724IM5-4.63CS065247473430552700011568301341
    LM3724IM5X-3.08CS065247473430552700011568301341

    Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

    For more information on Reliability Metrics, please click here.


    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM3724.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM3724 is located at RoHS Status.

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM3724EM5-2.32
    		NONE
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM3724IM5X-2.32
    		NONE
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009

    [Information as of 9-Feb-2012]
    Copyright © 2011 National Semiconductor Corporation