Nexperia USA Inc. 74HCT27DB,118

Overview

74HCT27DB,118 from Nexperia is a triple 3-input NOR gate logic IC with TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 5.0 V), 4.5–5.5 V supply range, and guaranteed operation from –40 °C to +125 °C in SO14 (SOT108-1) package. It delivers 12 ns typical propagation delay (VCC = 4.5 V, CL = 15 pF) and supports industrial control bus arbitration, reset signal conditioning, and enable logic in programmable logic interfaces.

For engineers reviewing the 74HCT27DB,118 datasheet, 74HCT27DB,118 pinout, 74HCT27DB,118 application, or 74HCT27DB,118 equivalent, key selection criteria include TTL-level input compatibility, SO14 thermal derating (10.1 mW/K above 100 °C), output drive capability (±4.0 mA), latch-up immunity (>100 mA), and ESD robustness (HBM >2000 V).

Technical Context

This device implements three independent 3-input NOR gates in a single monolithic CMOS structure with integrated input clamp diodes enabling safe interfacing to voltages exceeding VCC via external current-limiting resistors. Each gate exhibits symmetrical HIGH/LOW output voltage specs (VOH ≥ 3.98 V, VOL ≤ 0.26 V at IO = ±4.0 mA, VCC = 4.5 V) and operates with static input leakage < ±0.1 μA at 25 °C.

Dynamic behavior is characterized by propagation delay (tpd) and transition time (tt) measured per IEC 60134-compliant test circuit (Fig. 5), using defined measurement points (VM = 1.3 V for HCT, VX = 0.1×VCC, VY = 0.9×VCC). Power dissipation is modeled via CPD = 30 pF and dynamic equation PD = CPD × VCC² × fi × N + Σ(CL × VCC² × fo).

Key Specifications

Pinout & Package

74HCT27DB,118 is supplied in SO14 (SOT108-1) plastic small outline package: 14-lead, 3.9 mm body width, 1.27 mm lead pitch, JEDEC MS-012 compliant. Thermal resistance θJA = 100 K/W; total power dissipation derates linearly at 10.1 mW/K above 100 °C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple 3-input NOR gate applications.

Compared with 74HCT27DB,118, the 74HCT27D,118 offers identical performance in the same SO14 footprint, while SN74HCT27N trades miniaturization and thermal efficiency for mechanical serviceability - making the DB variant optimal for production-grade SMT industrial controllers.

Availability

74HCT27DB,118 is available at Aetrix Electronics and suitable for industrial bus arbitration, microcontroller reset conditioning, and programmable logic enable trees requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HCT27DB,118 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 logic, analog, and discrete components optimized for efficiency, reliability, and manufacturability in high-volume applications.

The 74HCT27 belongs to Nexperia's industry-standard 74HCT logic family, engineered for seamless interoperability with legacy TTL systems while leveraging CMOS power efficiency and noise immunity in industrial and automotive-adjacent control applications.

FAQ

Is 74HCT27DB,118 compatible with 3.3 V logic systems?

No - 74HCT27DB,118 is specified only for 4.5–5.5 V operation and features TTL-level input thresholds (VIH = 2.0 V min). Driving it from 3.3 V sources risks unreliable HIGH detection; use 74LVC27 or 74AUP27 for true 3.3 V compatibility with rail-to-rail input thresholds.

Can 74HCT27DB,118 drive a 50 pF capacitive load at 10 MHz?

Yes - with CPD = 30 pF and typical tpd = 12 ns, dynamic power at 10 MHz and VCC = 5 V is ~7.5 mW (PD = CPD × VCC² × fi × N). Output rise/fall times remain <15 ns, ensuring signal integrity; add 33 Ω series termination if routing exceeds 5 cm.

What is the maximum allowable junction temperature for continuous operation?

The absolute maximum junction temperature is +150 °C (per Table 4 limiting values). At ambient +125 °C and θJA = 100 K/W, maximum allowed power dissipation is 2.5 W - but rated Ptot = 500 mW (derated above 100 °C), so practical Tj remains ≤125 °C under normal operating conditions.

Does the SO14 package include exposed thermal pad?

No - the SOT108-1 (SO14) package used for 74HCT27DB,118 has no thermal pad. Thermal performance relies on copper pour under pins 7 (GND) and 14 (VCC); for enhanced cooling, use 2 oz. copper and ≥4 thermal vias per pad connected to internal ground plane.