Texas Instruments SNJ54HC4002FK

Overview

SNJ54HC4002FK from Texas Instruments is a dual 2-input NOR gate logic IC in military-grade LCCC-20 package, operating over –55°C to +125°C, with typical propagation delay of 11 ns at V_CC = 5 V, fan-out of 10 LSTTL loads, and input clamp diodes for transient protection. It serves as a robust combinational logic element in radiation-tolerant avionics timing and control circuits.

For engineers reviewing the SNJ54HC4002FK datasheet, SNJ54HC4002FK pinout, SNJ54HC4002FK application, or SNJ54HC4002FK equivalent, key selection criteria include its MIL-PRF-38535 Class B qualification, SNPB (tin-lead) lead finish, hermetic LCCC packaging, and compatibility with legacy 54HC logic families in high-reliability embedded control systems.

Technical Context

The SNJ54HC4002FK implements two independent 2-input NOR gates using silicon-gate CMOS technology, ensuring low static power consumption (<2 µA at 25°C) while maintaining TTL-compatible voltage thresholds. Its design supports direct interface with LSTTL and other 5-V logic families without level-shifting.

It conforms to the 54HC logic family's AC/DC electrical specifications per TI's SCLS069E datasheet, including guaranteed high-level output voltage ≥4.4 V (V_CC = 4.5 V), low-level output voltage ≤0.33 V, and noise margin of 1.0 V (high) / 1.2 V (low) under nominal conditions.

Key Specifications

Pinout & Package

LCCC-20 (FK) package: 8.89 mm × 8.89 mm ceramic body, 1.27 mm pin pitch, 20-terminal leadless construction with metallized perimeter terminations. Hermetically sealed with glass-frit lid per MIL-STD-1835.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual NOR gate applications.

Compared with JM38510/65104BCA and SN54HC4002J, the SNJ54HC4002FK uniquely delivers hermetic LCCC packaging, Class B qualification, and NC pin configuration - making it the only choice for space-qualified or safety-critical airborne systems requiring zero moisture permeability and full lot traceability.

Availability

SNJ54HC4002FK is available at Aetrix Electronics and suitable for avionics flight control, spacecraft telemetry processing, missile guidance sequencing, and nuclear safety interlock systems requiring stable component supply across extended product lifecycles.

Supply support for SNJ54HC4002FK 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

Texas Instruments is a U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and high-reliability logic solutions for industrial, aerospace, and defense markets.

The SNJ54HC4002FK belongs to TI's 54HC military logic family, designed specifically for applications demanding extended temperature operation, hermetic packaging, and compliance with MIL-PRF-38535 Class B screening requirements.

FAQ

What is the maximum propagation delay of SNJ54HC4002FK at 5 V supply?

The maximum propagation delay for SNJ54HC4002FK is 11 ns at V_CC = 5 V, measured under standard load conditions (C_L = 50 pF, T_A = 25°C). This value is guaranteed across the full –55°C to +125°C operating range per TI's SCLS069E datasheet, enabling precise timing budgeting in synchronous control designs that use the SNJ54HC4002FK.

Is SNJ54HC4002FK RoHS compliant?

No, SNJ54HC4002FK is not RoHS compliant. It features a tin-lead (SNPB) lead finish, which is exempt from RoHS Directive 2011/65/EU Annex III for high-reliability applications. This exemption supports compatibility with legacy soldering processes and avoids reliability risks associated with Pb-free reflow in hermetic ceramic packages like the SNJ54HC4002FK.

What does the 'FK' in SNJ54HC4002FK indicate?

The 'FK' suffix in SNJ54HC4002FK denotes the LCCC (Leadless Ceramic Chip Carrier) package with 20 terminals, per TI's packaging nomenclature. This distinguishes it from CDIP-14 versions (e.g., SNJ54HC4002J) and confirms its hermetic, surface-mount construction. The FK package is specified in MIL-STD-1835 and used exclusively for high-reliability variants of the SNJ54HC4002FK.

Can SNJ54HC4002FK operate at 3.3 V?

Yes, SNJ54HC4002FK operates over 2 V to 6 V, including 3.3 V nominal rails. At 3.3 V, its output high voltage is guaranteed ≥2.5 V and output low voltage ≤0.5 V, supporting interoperability with 3.3-V logic families. However, propagation delay increases to ~15 ns, and fan-out reduces - design margins must be verified using the SNJ54HC4002FK's DC/AC specs at that voltage.

Why does SNJ54HC4002FK have six no-connect pins?

SNJ54HC4002FK has six no-connect (NC) pins (pins 15–20) due to the LCCC-20 footprint accommodating future family expansion and mechanical symmetry. These pins are unbonded and electrically isolated per TI's SCLS069E; they must remain unconnected in layout. This design allows shared PCB land patterns across multiple 54HC logic devices while maintaining mechanical stability in the SNJ54HC4002FK's ceramic package.