onsemi MC74AC08MELG

Overview

MC74AC08MELG from onsemi is a quad 2-input AND gate in high-performance silicon-gate CMOS technology, operating at supply voltages from 2.0 V to 6.0 V, delivering ±24 mA output drive, with propagation delays as low as 5.5 ns (VCC = 5.0 V, CL = 50 pF), and designed for general-purpose logic interfacing in industrial control and digital signal routing.

For engineers reviewing the MC74AC08MELG datasheet, pinout, applications, or equivalent options, this device supports TTL- and CMOS-compatible logic families, offers Pb-free SOIC-14 packaging, meets AEC-Q100 stress requirements when qualified with −Q suffix, and provides verified DC/AC performance across −40°C to +85°C ambient operation.

Technical Context

The MC74AC08MELG implements four independent 2-input AND gates using advanced silicon-gate CMOS process, enabling rail-to-rail output swing and low static current consumption (ICC ≤ 4.0 µA at VCC = 5.5 V). Its input thresholds are CMOS-compatible (VIH = 3.85 V min at VCC = 5.5 V), and it exhibits robust noise immunity with VIH/VIL margins exceeding 1.65 V at 5.5 V supply.

It operates within a recommended supply range of 2.0–6.0 V for 'AC logic family behavior, supports 50 pF capacitive loads per output, and maintains guaranteed tPLH/tPHL ≤ 8.5 ns over full temperature range - critical for synchronous bus gating and enable-path timing in embedded controllers and interface logic.

Key Specifications

Pinout & Package

MC74AC08MELG is supplied in a Pb-free SOIC-14 package (Case 751A), measuring 8.55 mm × 3.80 mm × 1.75 mm, with standard 1.27 mm pitch and 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 AND gate applications.

Compared with SN74AC08DR and 74VHC08M, the MC74AC08MELG delivers identical timing and drive strength with onsemi's AEC-Q100-capable manufacturing traceability, tighter VIH/VIL guarantees at 5.5 V, and documented Pb-free compliance per J-STD-020 - making it optimal for industrial designs requiring long-term component continuity and audit-ready documentation.

Availability

MC74AC08MELG is available at Aetrix Electronics and suitable for industrial automation, sensor interface modules, and embedded power management systems requiring stable component supply, long-lifecycle support, and RoHS-compliant procurement.

Supply support for MC74AC08MELG 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 innovation for automotive, industrial, cloud, medical, and IoT applications.

The MC74AC08MELG belongs to the 74AC logic family - engineered for high-speed, low-power CMOS interoperability in mixed-voltage digital systems where timing predictability and supply flexibility are essential.

FAQ

What logic family does MC74AC08MELG belong to, and how does it differ from 74ACT variants?

The MC74AC08MELG belongs to the 74AC logic family, featuring CMOS-compatible input thresholds (VIH ≥ 3.85 V at VCC = 5.5 V) and rail-to-rail outputs. Unlike the 74ACT variant (e.g., MC74ACT08), it does not guarantee TTL-compatible inputs - meaning its VIH is higher and not optimized for direct connection to legacy TTL outputs. This makes MC74AC08MELG ideal for pure CMOS systems or mixed 3.3 V/5 V environments where input noise margins are prioritized over TTL interoperability.

Can MC74AC08MELG operate reliably at 3.3 V supply, and what are its key timing parameters at that voltage?

Yes, MC74AC08MELG is fully specified down to 2.0 V and operates reliably at 3.3 V. At VCC = 3.3 V and CL = 50 pF, typical propagation delay is 7.5 ns (tPLH/tPHL), with guaranteed maximum of 10.0 ns over −40°C to +85°C. Input thresholds scale proportionally (VIH = 1.5 V min, VIL = 0.9 V max), ensuring clean switching with standard 3.3 V logic drivers and compatible with LVTTL and LVCMOS interfaces.

Does MC74AC08MELG support hot-swap or live-insertion applications?

No, MC74AC08MELG is not characterized for hot-swap operation. Its absolute maximum ratings specify VCC from −0.5 V to +6.5 V and VI from −0.5 V to VCC + 0.5 V, but the device lacks built-in power-up/power-down sequencing protection, bus-hold, or Ioff partial-power-down features. For live-insertion, external series resistors and clamping diodes are required to limit transient currents during pin engagement - refer to onsemi Application Note AND8003/D for safe implementation guidelines.

What is the thermal resistance (θJA) of MC74AC08MELG in its SOIC-14 package, and how does it affect power dissipation?

The MC74AC08MELG in SOIC-14 (Case 751A) has a junction-to-ambient thermal resistance (θJA) of 116°C/W under still-air conditions. At maximum rated power dissipation of 1077 mW, this yields a worst-case junction temperature rise of ~125°C above ambient - limiting practical continuous operation to ≤ 500 mW in 85°C ambient unless board-level thermal relief (e.g., copper pour, airflow) is applied. Derating curves in the datasheet confirm safe operation up to 85°C ambient at full output loading.

Is MC74AC08MELG pin-compatible with other 74-series quad AND gate packages such as 74LS08 or 74HC08?

Yes, MC74AC08MELG uses the industry-standard 14-pin SOIC footprint and identical pinout as 74LS08, 74HC08, and 74HCT08 - including GND on Pin 7 and VCC on Pin 14. All four AND gates map identically: Inputs on Pins 1&2 → Output Pin 3; Pins 4&5 → Pin 6; Pins 8&9 → Pin 10; Pins 12&13 → Pin 11. This allows direct PCB replacement in existing designs, provided voltage and timing requirements align with the AC family's 2.0–6.0 V range and sub-10 ns delays.