Nexperia USA Inc. 74AHC123ABQ,115

Overview

74AHC123ABQ,115 from Nexperia is a dual retriggerable monostable multivibrator with independent reset inputs, designed for precise pulse generation and extension in timing-critical digital systems. It operates from 2.0 V to 5.5 V, supports CMOS-level inputs, delivers programmable output pulse widths (90 μs to 1.15 ms with REXT = 10 kΩ, CEXT = 0.01–0.1 μF), and features overvoltage-tolerant inputs up to 5.5 V. Used in industrial control sequencers, power-on reset synchronization, and debounce circuits where long, extendable pulses are required.

For engineers reviewing the 74AHC123ABQ,115 datasheet, 74AHC123ABQ,115 pinout, 74AHC123ABQ,115 application, or 74AHC123ABQ,115 equivalent, key selection criteria include retriggerable pulse extension capability, dual independent monostable channels, Schmitt-trigger input noise immunity, and DHVQFN16 thermal-enhanced packaging for high-density PCB layouts.

Technical Context

This device implements two independent edge-triggered monostable circuits, each with separate negative-edge (nA) and positive-edge (nB) trigger inputs, active-low direct reset (nRD), and complementary outputs (nQ, nQ). Pulse width is externally set via REXT and CEXT per channel, with typical tW = CEXT × REXT (for CEXT ≥ 10 nF).

Each channel supports retriggering during an active output pulse to extend duration indefinitely-enabling 100% duty factor operation-and allows immediate termination via nRD. Inputs include Schmitt-trigger action for high noise immunity, and all pins tolerate voltages up to 5.5 V regardless of VCC, enabling mixed-voltage interface translation.

Key Specifications

Pinout & Package

DHVQFN16 package (SOT763-1): 2.5 mm × 3.5 mm × 0.85 mm body, 16-terminal no-lead thermal-enhanced quad flat layout with exposed thermal pad (non-soldered by default); optimized for high thermal conductivity and compact routing in space-constrained applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar monostable multivibrator applications.

Compared with 74AHCT123ABQ,115, the AHC variant offers broader supply flexibility and true overvoltage tolerance, while SN74LVC123APWR trades interface robustness for lower voltage operation and reduced footprint - making the 74AHC123ABQ,115 optimal for mixed-voltage industrial and automotive timing where reliability trumps minimal size.

Availability

74AHC123ABQ,115 is available at Aetrix Electronics and suitable for industrial motor control sequencing, automotive door lock debounce, and medical infusion pump safety timeout requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74AHC123ABQ,115 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Nexperia is a global semiconductor expert focused on essential efficiency technologies, delivering high-performance logic, discrete, and MOSFET solutions for automotive, industrial, and consumer markets.

The 74AHC123A series belongs to Nexperia's advanced logic portfolio, engineered specifically for robust, retriggerable timing in electrically noisy and thermally demanding environments - emphasizing reliability, wide voltage operation, and mixed-signal interoperability.

FAQ

What is the minimum external capacitor value supported for stable pulse width generation?

The datasheet specifies no lower limit for CEXT; however, stability requires CEXT ≥ 10 nF for predictable tW = CEXT × REXT behavior. With CEXT < 10 nF, pulse width deviates from linear scaling and becomes sensitive to parasitic capacitance - use CEXT ≥ 28 pF only for sub-microsecond timing where accuracy is secondary to speed.

Can both channels be triggered simultaneously without interference?

Yes - channels are electrically isolated except for shared VCC and GND rails. Simultaneous triggering of 1A/1B and 2A/2B produces independent output pulses with no crosstalk or timing skew. Measured inter-channel propagation delay variation is <100 ps under matched load conditions.

How should the thermal pad on the DHVQFN16 package be handled?

The exposed thermal pad (terminal 1 index area) has no electrical function and requires no solder connection. If soldered, it must remain floating or connect exclusively to PCB GND - never to VCC or signal nets. Thermal performance improves by 15% when thermally anchored to a 20 mm² copper pour.

Is the 74AHC123ABQ,115 suitable for use as a precision oscillator?

No - it is a monostable multivibrator, not an astable oscillator. While external RC components define pulse width, it lacks built-in feedback for continuous oscillation. For oscillator applications, use dedicated clock generators or crystal-based solutions; this IC serves only single-shot or retriggered pulse generation.