onsemi MC74HC08ADT

Overview

MC74HC08ADT from ON Semiconductor is a quad 2-input AND gate in SOIC-14 package, implementing high-performance silicon-gate CMOS logic with 2.0–6.0 V supply operation, 13 ns propagation delay at 6.0 V, and ±25 mA output drive per pin. It serves as a level-translating combinational logic element in digital control, interface buffering, and enable gating circuits.

For engineers reviewing the MC74HC08ADT datasheet, pinout, applications, or equivalent options, this page delivers verified electrical specs, package mapping to SOIC-14 (Case 751A), functional truth table compliance, and real-world substitution guidance for industrial and embedded logic design.

Technical Context

The MC74HC08ADT implements four independent AND gates in a single monolithic CMOS IC, each with identical input threshold behavior (VIH = 4.20 V min at VCC = 6.0 V; VIL = 1.80 V max) and rail-to-rail output swing. Its inputs are compatible with both CMOS and LSTTL outputs-when pulled up, they accept LSTTL logic levels.

It operates across –55°C to +125°C, supports 50 pF capacitive loads, and exhibits low quiescent current (ICC ≤ 40 µA at 6.0 V, 125°C). The device conforms to JEDEC Std No. 7A and integrates 24 FETs (6 equivalent gates) on-die.

Key Specifications

Pinout & Package

MC74HC08ADT is supplied in a 14-lead SOIC package (Case 751A, D suffix), 3.90 mm wide, with standard 1.27 mm pitch. Pin 1 is marked by a beveled corner or notch; Pin 7 = GND, Pin 14 = VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC08DR and 74HC08D,653, the MC74HC08ADT offers broader temperature coverage (–55°C to +125°C), lower quiescent current, and explicit LSTTL load compatibility-making it preferred for ruggedized industrial and automotive control logic where thermal margin and drive strength are critical.

Availability

MC74HC08ADT is available at Aetrix Electronics and suitable for industrial control logic, microcontroller interface buffering, automotive body electronics, and test equipment signal conditioning requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MC74HC08ADT 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, logic, and sensor solutions for automotive, industrial, and cloud infrastructure markets.

The MC74HC08ADT belongs to the HC-series high-speed CMOS logic family, designed for robust, low-power digital interfacing and control in harsh environments where reliability, wide voltage range, and temperature resilience are essential.

FAQ

What is the maximum operating temperature for the MC74HC08ADT?

The MC74HC08ADT is rated for operation from –55°C to +125°C across all package types, including the SOIC-14 variant. This specification is guaranteed per the Recommended Operating Conditions table in the official ON Semiconductor datasheet (Rev. 9, 2005), making MC74HC08ADT suitable for under-hood automotive and extended-temperature industrial applications where thermal stability is critical.

Does the MC74HC08ADT support 3.3 V logic systems?

Yes, the MC74HC08ADT fully supports 3.3 V operation: its recommended supply range is 2.0 V to 6.0 V, and at VCC = 3.3 V, it guarantees VIH ≥ 2.1 V and VIL ≤ 0.9 V - comfortably accommodating standard 3.3 V CMOS logic levels. The MC74HC08ADT also maintains 15 ns max propagation delay and ±25 mA drive capability at this voltage, ensuring reliable performance in mixed-voltage digital systems.

Is the MC74HC08ADT pin-compatible with TTL AND gates like the 74LS08?

Yes, the MC74HC08ADT is explicitly designed to be pinout-identical to the 74LS08, as confirmed in the datasheet: "The MC74HC08A is identical in pinout to the LS08." All 14 pins-including VCC (14), GND (7), and the four A/B/Y signal groups-match exactly. However, note that MC74HC08ADT requires pull-up resistors on inputs when interfacing with LSTTL outputs to ensure proper logic thresholds, unlike the LS08 which is TTL-native.

What is the input capacitance of the MC74HC08ADT?

The MC74HC08ADT has a maximum input capacitance (Cin) of 10 pF per input pin, as specified in the AC Characteristics table of the datasheet. This low value minimizes loading on driving sources and supports high-speed signal integrity in dense PCB layouts. The 10 pF figure applies across the full operating temperature range and is measured with CL = 50 pF and input rise/fall times of 6 ns.

Can unused inputs on the MC74HC08ADT be left floating?

No - unused inputs on the MC74HC08ADT must never be left floating. The datasheet explicitly states: "Unused inputs must always be tied to an appropriate logic voltage level (e.g., either GND or VCC)." Floating CMOS inputs can drift into the linear region, causing excessive supply current, oscillation, or unpredictable output states. For the MC74HC08ADT, tie unused A/B pins directly to VCC or GND using short traces to maintain stable logic behavior and prevent increased ICC or thermal stress.