onsemi MC74ACT02D

Overview

MC74ACT02D from onsemi is a quad 2-input NOR gate in SOIC-14 package, designed for high-speed TTL-compatible logic interfacing at 5 V supply. It delivers 24 mA output drive, supports −40°C to +85°C operation, features 8.5 ns max propagation delay (tPLH/tPHL), and meets Pb-free RoHS compliance. It serves as a core combinational logic element in industrial control signal conditioning and digital bus arbitration circuits.

For engineers reviewing the MC74ACT02D datasheet, pinout, applications, or equivalent options, this page provides verified functional identity, validated SOIC-14 pin mapping, confirmed TTL-compatible input thresholds, real-world timing performance under 50 pF load, and two manufacturer-validated alternative parts with documented electrical and application differences.

Technical Context

The MC74ACT02D implements four independent 2-input NOR gates using advanced silicon-gate CMOS technology. Its inputs are TTL-compatible (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 4.5–5.5 V), enabling direct interface with legacy 5 V TTL families without level-shifting.

Each gate provides symmetrical output drive: IOH = −24 mA and IOL = 24 mA at VCC = 5.0 V, with VOL ≤ 0.44 V and VOH ≥ 3.76 V under full load. Propagation delays are specified at CL = 50 pF and TA = −40°C to +85°C, with tPHL/tPLH ≤ 10 ns max at 5.0 V.

Key Specifications

Pinout & Package

MC74ACT02D is supplied in a 14-lead SOIC (Small Outline Integrated Circuit) package, case outline 751A, with 1.27 mm pitch and Pb-free finish (suffix D). Dimensions: 8.75 × 3.90 × 1.75 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input NOR gate applications.

Compared with MC74ACT02D, SN74ACT02DR offers marginally better typical speed but narrower input noise margin, while 74VHC02M enables dual-supply flexibility at the cost of TTL compatibility and reduced drive - making MC74ACT02D optimal for robust 5 V industrial retrofits requiring guaranteed 24 mA sink/source.

Availability

MC74ACT02D is available at Aetrix Electronics and suitable for industrial PLC input conditioning, digital bus arbitration logic, legacy system logic retrofit, and power sequencing control requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MC74ACT02D 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 specializing in energy-efficient power management, analog, sensors, and logic solutions for automotive, industrial, and cloud infrastructure markets.

The MC74ACT02D belongs to onsemi's 74ACT high-speed CMOS logic family, engineered specifically for 5 V systems requiring TTL compatibility, robust output drive, and industrial temperature resilience without sacrificing speed or power efficiency.

FAQ

What is the maximum supply voltage rating for MC74ACT02D?

The absolute maximum DC supply voltage (VCC) for MC74ACT02D is +6.5 V, but the recommended operating range is strictly 4.5 V to 5.5 V. Operation above 5.5 V risks exceeding input/output voltage limits and may cause latch-up or accelerated wear-out. All published timing and drive specifications assume VCC = 5.0 V ±0.5 V, and the device is not characterized for reliable operation at 3.3 V or below.

Does MC74ACT02D support 3.3 V logic level inputs?

No, MC74ACT02D does not reliably accept 3.3 V logic level inputs. Its TTL-compatible input thresholds require VIH ≥ 2.0 V and VIL ≤ 0.8 V at VCC = 5.0 V - while a 3.3 V high signal may exceed VIH, it falls outside the guaranteed switching region and risks marginal operation or increased static current. For 3.3 V systems, use 74VHC02 or level-shifting buffers instead of MC74ACT02D.

What is the thermal resistance (θJA) of MC74ACT02D in SOIC-14 package?

The junction-to-ambient thermal resistance (θJA) for MC74ACT02D in SOIC-14 package is 116°C/W, measured per JESD51-7 under standard PCB conditions (1-inch² copper pad, 1 oz Cu). This value assumes no additional heatsinking; actual θJA will improve with larger copper areas or thermal vias. At maximum rated power dissipation (1077 mW), this yields ~125°C junction rise above ambient - well within the 150°C TJ limit when ambient stays ≤25°C.

Can MC74ACT02D drive a 50 pF capacitive load within its specified propagation delay?

Yes, MC74ACT02D's AC characteristics are explicitly tested and guaranteed at CL = 50 pF. The datasheet specifies tPLH ≤ 9.0 ns and tPHL ≤ 10 ns under these exact conditions at VCC = 5.0 V and TA = −40°C to +85°C. Driving heavier loads (>50 pF) increases delay nonlinearly and may violate setup/hold timing in synchronous systems - for >50 pF, add series termination or buffer stages rather than relying on MC74ACT02D alone.

Is MC74ACT02D pin-compatible with the older 74LS02 TTL device?

Yes, MC74ACT02D uses the identical SOIC-14 pinout as 74LS02 and performs the same quad 2-input NOR logic function. Its TTL-compatible inputs (VIH/VIL) and 5 V supply requirement make it a functional and physical drop-in replacement. However, note that MC74ACT02D draws significantly less quiescent current (40 μA vs. ~15 mA for 74LS02) and delivers higher output drive (±24 mA vs. ±8 mA), which may affect pull-up resistor sizing or fan-out calculations in legacy designs.