74AHCT123AD: Dual retriggerable monostable multivibrator with reset

The 74AHC123A; 74AHCT123A are high-speed Si-gate CMOS devices and are pin compatible with Low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A.

The 74AHC123A; 74AHCT123A are dual retriggerable monostable multivibrators with output pulse width control by three methods. The basic pulse time is programmed by selection of an external resistor (REXT) and capacitor (CEXT).

Once triggered, the basic output pulse width may be extended by retriggering the gated active LOW-going edge input (nA) or the active HIGH-going edge input (nB). By repeating this process, the output pulse period (nQ = HIGH, nQ = LOW) can be made as long as desired. Alternatively an output delay can be terminated at any time by a LOW-going edge on input nRD, which also inhibits the triggering.

An internal connection from nRD to the input gate makes it possible to trigger the circuit by a positive-going signal at input nRD. The basic output pulse width is essentially determined by the value of the external timing components REXT and CEXT. When CEXT ≥ 10 nF, the typical output pulse width is defined as: tW= REXT× CEXT where tW= pulse width in ns; REXT= external resistor in kΩ; CEXT= external capacitor in pF. Schmitt-trigger action at all inputs makes the circuit highly tolerant to slower input rise and fall times.

74AHCT123AD: Product Block Diagram
sot109-1_3d
Data Sheets (1)
Name/DescriptionModified Date
Dual retriggerable monostable multivibrator with reset (REV 4.0) PDF (308.0 kB) 74AHC_AHCT123A [English]24 Nov 2011
Application Notes (5)
Name/DescriptionModified Date
Sorting through the low voltage logic maze (REV 1.0) PDF (72.0 kB) AN10156 [English]13 Mar 2013
Package lead inductance considerations in high-speed applications (REV 1.0) PDF (43.0 kB) AN212 [English]13 Mar 2013
Ground and VCC Bounce of High-Speed Integrated Circuits (REV 1.0) PDF (25.0 kB) AN223 [English]13 Mar 2013
Live Insertion Aspects of Philips Logic Families (REV 1.0) PDF (73.0 kB) AN252 [English]13 Mar 2013
Pin FMEA for AHC/AHCT family (REV 1.0) PDF (52.0 kB) AN11106 [English]04 Nov 2011
Brochures (2)
Name/DescriptionModified Date
電圧レベルシフタ (REV 1.1) PDF (3.1 MB) 75017511_JP [English]16 Feb 2015
Voltage translation: How to manage mixed-voltage designs with NXP® level translators (REV 1.0) PDF (2.6 MB) 75017511 [English]20 May 2014
Selector Guides (2)
Name/DescriptionModified Date
ロジック製品セレクションガイド... (REV 1.0) PDF (38.3 MB) LOGIC_SELECTION_GUIDE_2015_JP [English]19 Nov 2015
Logic selection guide 2016 (REV 1.1) PDF (15.3 MB) 75017285 [English]08 Jan 2015
Package Information (1)
Name/DescriptionModified Date
plastic small outline package; 16 leads; body width 3.9 mm (REV 1.0) PDF (192.0 kB) SOT109-1 [English]08 Feb 2016
Packing (1)
Name/DescriptionModified Date
SO16; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... (REV 4.0) PDF (210.0 kB) SOT109-1_118 [English]24 Apr 2013
Supporting Information (2)
Name/DescriptionModified Date
Footprint for reflow soldering (REV 1.0) PDF (9.0 kB) SO-SOJ-REFLOW [English]08 Oct 2009
Footprint for wave soldering (REV 1.0) PDF (8.0 kB) SO-SOJ-WAVE [English]08 Oct 2009
IBIS Model
Ordering Information
ProductStatusFamilyFunctionVCC (V)DescriptionLogic switching levelsPackage versionOutput drive capability (mA)tpd (ns)Power dissipation considerationsTamb (Cel)Rth(j-a) (K/W)Ψth(j-top) (K/W)Rth(j-c) (K/W)Package nameNo of pins
74AHCT123ADActiveAHC(T)Multivibrators4.5 - 5.5TTL enabledTTLSOT109-1+/- 85low-40~1259310.153SO1616
Package Information
Product IDPackage DescriptionOutline VersionReflow/Wave SolderingPackingProduct StatusPart NumberOrdering code(12NC)MarkingChemical ContentRoHS / Pb Free / RHFLeadFree Conversion DateEFRIFR(FIT)MTBF(hour)MSLMSL LF
74AHCT123ADSOT109-1SO-SOJ-REFLOW SO-SOJ-WAVE
SO-SOJ-REFLOW SO-SOJ-WAVE
Reel 13" Q1/T1Active74AHCT123AD,118 (9352 655 61118)74AHCT123AD74AHCT123ADweek 5, 200584.96.621.51E811
Bulk PackActive74AHCT123AD,112 (9352 655 61112)74AHCT123AD74AHCT123ADweek 5, 200584.96.621.51E811
Dual retriggerable monostable multivibrator with reset 74AHCT123APW
Sorting through the low voltage logic maze 74LVC_H_245A_Q100
Package lead inductance considerations in high-speed applications 74LVC_H_245A_Q100
Ground and VCC Bounce of High-Speed Integrated Circuits 74ALVC164245DGG-Q100
Live Insertion Aspects of Philips Logic Families 74HC_T_245_Q100
Pin FMEA for AHC/AHCT family 74AHC_T_245_Q100
電圧レベルシフタ 74AVC16245DGG-Q100
Voltage translation: How to manage mixed-voltage designs with NXP® level translators 74AVC16245DGG-Q100
ロジック製品セレクションガイド... 74LVC_H_245A_Q100
Logic selection guide 2016 74LVC_H_245A_Q100
ahct123a IBIS model 74AHCT123APW
plastic small outline package; 16 leads; body width 3.9 mm NPIC6C596A_Q100
Footprint for reflow soldering NPIC6C596A_Q100
Footprint for wave soldering NPIC6C596A_Q100
SO16; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... NPIC6C596A_Q100
74AHC_T_123A
SA614A