onsemi MC74AC32NG

Overview

MC74AC32NG from onsemi is a quad 2-input OR gate in high-performance silicon-gate CMOS technology, operating across 2.0 V to 6.0 V supply range, delivering ±24 mA output drive, with propagation delay as low as 5.5 ns at 5.0 V and 50 pF load, used in digital logic interfacing, bus arbitration, and level translation in industrial control systems.

For engineers reviewing the MC74AC32NG datasheet, pinout, applications, or equivalent options, this page provides verified functional identity, SOIC-14 package mapping, DC/AC electrical specs, real-world use scenarios, and two validated alternative parts for design flexibility and supply continuity.

Technical Context

The MC74AC32NG implements four independent OR logic functions using CMOS transistor pairs with rail-to-rail input thresholds and complementary output stages. It supports mixed-voltage system interfacing due to its wide VCC range (2.0–6.0 V) and TTL-compatible input thresholds only in the ACT variant-not applicable to MC74AC32NG.

Its logic behavior follows standard positive-logic OR truth table per gate: output high when either or both inputs are high; output low only when both inputs are low. Input leakage remains ≤±1.0 µA at 5.5 V, and dynamic output current capability reaches ±75 mA under pulsed conditions (VOLD ≤1.65 V / VOHD ≥3.85 V).

Key Specifications

Pinout & Package

MC74AC32NG is supplied in a Pb-free SOIC-14 (Case 751A) package, 8.75 mm × 3.90 mm body size, 1.27 mm pitch, with standard gull-wing leads suitable for reflow soldering per J-STD-020.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input OR gate applications.

Compared with SN74AC32DR and 74VHC32M, MC74AC32NG offers best-in-class propagation delay consistency across temperature (−40°C to +85°C) and optimal noise margin at 3.3 V operation, making it preferred for time-critical industrial control logic where timing predictability outweighs minimal quiescent current savings.

Availability

MC74AC32NG is available at Aetrix Electronics and suitable for industrial automation, test equipment, and embedded control applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for MC74AC32NG 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient electronics, delivering power management, analog, sensors, and logic solutions for automotive, industrial, and cloud infrastructure markets.

The MC74AC32NG belongs to the 74AC logic family designed for high-speed, low-power, mixed-voltage digital interfacing in harsh-environment industrial systems where reliability and parametric consistency are critical.

FAQ

What logic family does MC74AC32NG belong to, and how does it differ from 74ACT variants?

MC74AC32NG belongs to the 74AC (Advanced CMOS) logic family. Unlike the 74ACT variant, MC74AC32NG features CMOS-input thresholds (VIH ≈ 0.7×VCC), not TTL-compatible inputs. This means it requires higher input voltage levels for logic high recognition compared to MC74ACT32, which accepts standard TTL thresholds (VIH = 2.0 V min). The MC74AC32NG is optimized for clean CMOS system integration rather than legacy TTL interfacing.

Is MC74AC32NG pin-compatible with MC74AC32DG or MC74AC32DR2G?

Yes, MC74AC32NG is pin-compatible with MC74AC32DG and MC74AC32DR2G - all share identical SOIC-14 (Case 751A) footprint and pinout. The suffix "NG" denotes Pb-free packaging with same mechanical dimensions and soldering profile as "DG" (rail) and "DR2G" (tape-and-reel). No PCB layout changes are needed when substituting among these variants.

What is the maximum recommended operating frequency for MC74AC32NG in a 50 pF load configuration?

While MC74AC32NG is not characterized for maximum clock frequency, its typical propagation delay is 5.5 ns at 5.0 V and 50 pF load. Assuming symmetrical rise/fall times and conservative timing margin, reliable toggle rates up to ~80 MHz are achievable in well-designed PCB layouts. For synchronous systems, ensure setup/hold times of upstream drivers exceed tPLH/tPHL plus board trace skew.

Does MC74AC32NG support partial power-down or Ioff protection?

No, MC74AC32NG does not include Ioff (power-off protection) or partial power-down functionality. When VCC = 0 V, input and output structures are not isolated - applying signals to inputs or outputs may cause unintended current flow through internal diodes. Always power VCC before asserting any logic signals to prevent latch-up or damage.

Can MC74AC32NG operate reliably at 3.3 V supply with 5 V-tolerant inputs?

No, MC74AC32NG is not 5 V-tolerant. Its absolute maximum input voltage is VCC + 0.5 V per datasheet (VI ≤ VCC + 0.5 V). At 3.3 V supply, inputs must remain ≤3.8 V. Direct connection to 5 V logic violates this rating and risks permanent damage. Use level translators or resistive dividers if interfacing with 5 V sources.