Nexperia USA Inc. 74HC423D,653

Overview

74HC423D,653 from Nexperia is a dual retriggerable monostable multivibrator IC in SO16 package, providing two independent timing channels with active-HIGH/LOW edge-triggered inputs (1A/1B, 2A/2B), direct active-LOW reset (1RD/2RD), and complementary outputs (1Q/1Q, 2Q/2Q). It supports external REXT–CEXT timing (2 kΩ–1000 kΩ / no capacitor limit), operates from 2.0 V to 6.0 V, and delivers pulse widths up to 450 μs at 5 V with REXT = 10 kΩ and CEXT = 100 nF - used in industrial control timing, debounce circuits, and programmable delay generators.

For engineers reviewing the 74HC423D,653 datasheet, 74HC423D,653 pinout, 74HC423D,653 application, or 74HC423D,653 equivalent, this page provides verified functional identity, SO16 pin mapping, real-world timing behavior under retriggering, reset response latency (19–65 ns), and validated alternatives for monostable timing replacement in non-automotive embedded systems.

Technical Context

The 74HC423D implements two independent CMOS-based monostable multivibrators, each with Schmitt-trigger inputs on A/B pins (enabling tolerance to slow edges) and a dedicated active-LOW reset input that forces Q LOW and Q HIGH while blocking further triggering. Pulse width is set by external REXT and CEXT components, and retriggering extends the output pulse without requiring full timeout - enabling duty-cycle flexibility up to 100 %.

It uses standard HC logic family characteristics: VIH/VIL thresholds scale with VCC (e.g., VIH = 3.15 V min at VCC = 4.5 V), propagation delays range from 19 ns (VCC = 6.0 V) to 385 ns (VCC = 2.0 V), and it features input clamp diodes allowing safe interfacing to voltages exceeding VCC when current-limited.

Key Specifications

Pinout & Package

74HC423D,653 is housed in a plastic small outline package (SO16, SOT109-1) with 16 leads, 3.9 mm body width, and gull-wing leads suitable for automated assembly and AOI inspection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HC123D,653, the 74HC423D,653 offers true retriggerable behavior essential for adaptive timing, while SN74LVC1G123DBVR trades channel count for footprint reduction - making the 74HC423D optimal for dual, synchronized, extendable pulse generation in industrial control boards.

Availability

74HC423D,653 is available at Aetrix Electronics and suitable for industrial motor control, microcontroller input debounce, and programmable delay generator applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HC423D,653 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 delivering high-performance, reliable logic, analog, and discrete components optimized for efficiency and robustness in industrial and consumer systems.

The 74HC423 belongs to Nexperia's high-speed CMOS logic family, designed specifically for reliable timing, pulse shaping, and signal conditioning in noise-prone industrial environments with wide supply and temperature margins.

FAQ

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

The datasheet specifies that CEXT < 50 pF requires a power-up reset pulse to initialize correctly. No absolute minimum value is defined, but practical use starts at 10 pF. For CEXT > 10 pF, the pulse width formula tW = 0.45 × REXT × CEXT (typ.) applies at VCC = 5.0 V, and inherent pin capacitance is 7 pF - meaning total effective CEXT includes this parasitic term.

Can 74HC423D,653 be used with 3.3 V microcontrollers without level shifting?

Yes. With VCC = 3.3 V, VIH is guaranteed ≥ 2.1 V and VIL ≤ 1.35 V, fully compatible with standard 3.3 V CMOS logic levels. Outputs drive VOH ≥ 2.9 V and VOL ≤ 0.33 V at IO = ±4 mA, ensuring noise margin and reliable interfacing to 3.3 V inputs without translation.

How does retriggering affect the output pulse width calculation?

Retriggering resets the internal timing cycle - extending the HIGH or LOW output state without waiting for the original pulse to expire. The final pulse width equals the time from the first trigger to the last valid retrigger plus the base REXT–CEXT delay. Minimum retrigger interval is 110 ns (VCC = 5 V), below which pulses may not extend reliably.

Is the SO16 package RoHS-compliant and lead-free?

Yes. The 74HC423D,653 in SOT109-1 (SO16) package meets RoHS Directive 2011/65/EU and is lead-free, halogen-free, and compliant with Nexperia's environmental policy. The package uses matte tin (Sn) lead finish and conforms to JEDEC J-STD-020 moisture sensitivity level 3 (MSL3) for standard handling.