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74HC4538

Dual retriggerable precision monostable multivibrator

The 74HC4538 is a dual retriggerable-resettable monostable multivibrator. Each multivibrator has two trigger/retrigger inputs (nA and nB), a direct reset input (nCD), two complementary outputs (nQ and nQ), and two pins (nREXT/CEXT and nCEXT) for connecting the external timing components CEXT and REXT. Typical pulse width variation over temperature range is ± 0.2 %. The device may be triggered by either the positive or the negative edges of the input pulse. The duration and accuracy of the output pulse are determined by the external timing components CEXT and REXT. The output pulse width (TW) is equal to 0.7 × REXT × CEXT. The linear design techniques guarantee precise control of the output pulse width. A LOW level at nCD terminates the output pulse immediately. Schmitt-trigger action in the trigger inputs makes the circuit highly tolerant to slower rise and fall times. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of VCC.

Features and benefits

  • Wide supply voltage range from 2.0 to 6.0 V

  • CMOS low power dissipation

  • CMOS input levels

  • High noise immunity

  • Tolerant of slow trigger rise and fall times

  • Separate reset inputs

  • Triggering from falling or rising edge

  • Latch-up performance exceeds 100 mA per JESD 78 Class II Level B

  • Complies with JEDEC standards

    • JESD8C (2.7 V to 3.6 V)

    • JESD7A (2.0 V to 6.0 V)

  • ESD protection:

    • HBM JESD22-A114F exceeds 2000 V

    • MM JESD22-A115-A exceeds 200 V

  • Specified from -40 °C to +85 °C and from -40 °C to +125 °C

Parametrics

Type numberProduct statusVCC (V)Logic switching levelsOutput drive capability (mA)tpd (ns)Power dissipation considerationsTamb (°C)Rth(j-a) (K/W)Ψth(j-top) (K/W)Rth(j-c) (K/W)Package name
74HC4538DProduction2.0 - 6.0CMOS± 5.227low-40~125772.535SO16
74HC4538PWProduction2.0 - 6.0CMOS± 5.227low-40~1251091.037TSSOP16

Package

Type numberPackagePackage informationReflow-/Wave solderingPackingStatusMarkingOrderable part number, (Ordering code (12NC))
74HC4538D
SO16
(SOT109-1)
SOT109-1SO-SOJ-REFLOW
SO-SOJ-WAVE
SOT109-1_653Active74HC4538D74HC4538D,653
( 9337 149 10653 )
74HC4538PW
TSSOP16
(SOT403-1)
SOT403-1SSOP-TSSOP-VSO-WAVE
SOT403-1_118ActiveHC453874HC4538PW,118
( 9351 875 30118 )

The variants in the table below are discontinued. See the table Discontinuation information for more information.

Type numberPackagePackage informationReflow-/Wave solderingPackingStatusMarkingOrderable part number, (Ordering code (12NC))
74HC4538D
SO16
(SOT109-1)
SOT109-1SO-SOJ-REFLOW
SO-SOJ-WAVE
SOT109-1_652Withdrawn / End-of-life74HC4538D74HC4538D,652
( 9337 149 10652 )

Discontinuation information

Type numberOrderable part number, (Ordering code (12NC))Last time buy dateLast time delivery dateReplacement productStatusComments
74HC4538D9337149106522021-12-312022-06-3074HC4538D
    74HC4538PW9351875301122021-12-312022-06-3074HC4538PW

      Environmental information

      Type numberOrderable part numberChemical contentRoHSRHF-indicatorLeadfree conversion date
      74HC4538D74HC4538D,65374HC4538Dweek 12, 2005
      74HC4538PW74HC4538PW,11874HC4538PWweek 10, 2005

      The variants in the table below are discontinued. See the table Discontinuation information for more information.

      Type numberOrderable part numberChemical contentRoHSRHF-indicatorLeadfree conversion date
      74HC4538D74HC4538D,65274HC4538Dweek 12, 2005
      Quality and reliability disclaimer

      Documentation (11)

      File nameTitleTypeDate
      74HC4538Dual retriggerable precision monostable multivibratorData sheet2021-07-16
      AN11044Pin FMEA 74HC/74HCT familyApplication note2019-01-09
      Nexperia_Selection_guide_2023Nexperia Selection Guide 2023Selection guide2023-05-10
      hcHC/HCT Spice modelSPICE model2022-02-17
      HCT_USER_GUIDEHC/T User GuideUser manual1997-10-31
      SO-SOJ-WAVEFootprint for wave solderingWave soldering2009-10-08
      SO-SOJ-REFLOWFootprint for reflow solderingReflow soldering2009-10-08
      WAVE_BG-BD-1Wave soldering profileWave soldering2021-09-08
      SOT109-1plastic, small outline package; 16 leads; 1.27 mm pitch; 9.9 mm x 3.9 mm x 1.75 mm bodyPackage information2023-11-07
      SOT403-1plastic, thin shrink small outline package; 16 leads; 5 mm x 4.4 mm x 1.2 mm bodyPackage information2023-11-08
      SSOP-TSSOP-VSO-WAVEFootprint for wave solderingWave soldering2009-10-08

      Support

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      Models

      File nameTitleTypeDate
      hcHC/HCT Spice modelSPICE model2022-02-17

      Ordering, pricing & availability

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