Nexperia USA Inc. 74HC423D-Q100J

Overview

74HC423D-Q100 from Nexperia is a dual retriggerable monostable multivibrator with independent reset inputs, designed for precise pulse generation and extension in automotive timing circuits. It supports two external timing methods (REXT/CEXT), delivers active-HIGH and active-LOW outputs per channel, operates from 2.0 V to 6.0 V, and is qualified to AEC-Q100 Grade 1 (−40 °C to +125 °C) for engine control and body electronics applications.

For engineers reviewing the 74HC423D-Q100 datasheet, 74HC423D-Q100 pinout, 74HC423D-Q100 application, or 74HC423D-Q100 equivalent, key selection criteria include retriggerable pulse width control, Schmitt-trigger input tolerance, direct reset functionality, and SO16 package compatibility with automotive PCB assembly requirements.

Technical Context

The device implements two independent monostable circuits, each with dual-edge trigger capability (1A negative-edge, 1B positive-edge), dedicated active-LOW reset (1RD), and complementary outputs (1Q active-HIGH, 1Q active-LOW). Pulse width is programmable via external REXT and CEXT components, with typical tW = 0.45 × REXT × CEXT (μs) at VCC = 5.0 V.

Propagation delays range from 19 ns (VCC = 6.0 V) to 385 ns (VCC = 2.0 V); retrigger time trtrig is typ. 110 ns at VCC = 5.0 V, REXT = 5 kΩ, CEXT = 0 pF. All inputs except reset feature Schmitt-trigger action, enabling robust operation with slow-rising/falling signals.

Key Specifications

Pinout & Package

74HC423D-Q100 is housed in a 16-pin SO16 (SOT109-1) plastic small outline package with 3.9 mm body width, side-wettable flanks for AOI-compatible solder joint inspection, and standard 1.27 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HC123D-Q100, the 74HC423D-Q100 adds critical reset and retrigger capability for safety-critical timing; versus SN74LV123ADR, it delivers guaranteed automotive-grade reliability and wider voltage tolerance at the expense of slightly higher propagation delay.

Availability

74HC423D-Q100 is available at Aetrix Electronics and suitable for engine control units, body control modules, ADAS sensor interfaces, and powertrain diagnostic systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HC423D-Q100 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 specializing in high-performance, reliable logic, analog, and discrete components, with leadership in automotive-qualified devices and advanced packaging technologies.

The 74HC-Q100 series delivers AEC-Q100-compliant HC logic ICs optimized for automotive signal conditioning, timing, and interface functions - balancing speed, power efficiency, and ruggedness for under-hood and chassis applications.

FAQ

What is the minimum external capacitor value required for stable operation?

The device requires CEXT ≥ 50 pF for reliable power-up initialization without unintended pulses. For values below 50 pF, a reset pulse must be applied at startup per Figure 12. Capacitor values above 10 pF follow the formula tW = 0.45 × REXT × CEXT (μs) at VCC = 5.0 V, with inherent 7 pF test jig capacitance at pins 7 and 15 included in timing calculations.

Can both trigger inputs (nA and nB) be used simultaneously on the same channel?

Yes - nA (negative-edge) and nB (positive-edge) are logically OR'd internally per channel. Either edge can start or extend the output pulse, enabling flexible synchronization with mixed-edge clock or sensor signals. Retriggering is permitted only if the new trigger occurs after the minimum retrigger time (trtrig = 110 ns typ. at VCC = 5.0 V, REXT = 5 kΩ, CEXT = 0 pF).

How does the reset function interact with ongoing output pulses?

Asserting nRD LOW forces nQ LOW and nQ HIGH within ≤55 ns (VCC = 6.0 V), regardless of current pulse state, and blocks further triggering until nRD returns HIGH. This hard reset takes absolute priority over all trigger inputs and is fully asynchronous - essential for fail-safe system shutdown in automotive safety architectures.

Is the SO16 package compatible with automated optical inspection (AOI)?

Yes - the SOT109-1 package features side-wettable flanks specifically designed for AOI of solder joints. This enables 100% automated post-reflow inspection of gull-wing leads without X-ray, reducing defect escape in high-reliability automotive PCB assembly lines.