Texas Instruments 76038012A

Overview

76038012A from Texas Instruments is a military-grade quadruple 2-line to 1-line data selector/multiplexer in LCCC-20 package, operating over –55°C to +125°C, with TTL-compatible inputs and outputs, 16 ns typical propagation delay, and dual enable control per section for independent channel gating.

For engineers reviewing the 76038012A datasheet, 76038012A pinout, 76038012A application, or 76038012A equivalent, this device serves as a radiation-tolerant signal routing solution in avionics data buses, missile guidance logic, and hardened test instrumentation where deterministic timing, high-reliability packaging, and extended temperature operation are mandatory.

Technical Context

The 76038012A implements four independent 2:1 multiplexers sharing a common select line (S) and two active-low enable inputs (1G, 2G), each controlling two channels. Each section routes one of two input pairs (e.g., 1A/1B or 2A/2B) to its output (1Y or 2Y) based on S state when enabled.

It uses bipolar TTL circuitry with Schottky-clamped transistors to achieve guaranteed 16 ns max propagation delay (t_PLH/t_PHL) at V_CC = 5 V, ±10%, and supports fan-out of 10 LS-TTL loads. Input thresholds align with standard TTL logic levels (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V).

Key Specifications

Pinout & Package

LCCC-20 (FK) package: 20-terminal, leadless ceramic chip carrier with gold-plated terminations, designed for surface-mount soldering into high-reliability PTH or reflow assemblies. Hermetic seal meets MIL-STD-883 requirements.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar data selector applications.

Compared with SNJ54LS257BFK, 76038012A offers finer-grained channel control via dual enables per section; compared with JM38510/30906B2A, it shares identical performance but reflects earlier production lot coding - both meet identical QML-38535 requirements.

Availability

76038012A is available at Aetrix Electronics and suitable for avionics data multiplexing, missile guidance logic, and hardened test instrumentation requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for 76038012A 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 and embedded processing technologies with deep heritage in military and aerospace IC design.

The SN54LS257B/SN54LS258B family was developed in the 1970s to provide radiation-tolerant, high-speed TTL multiplexing for guidance computers and onboard telemetry systems in defense platforms.

FAQ

What is the maximum clock rate supported by the 76038012A for reliable data selection?

The 76038012A does not operate on a clock signal - it is a combinational logic device. Its maximum usable data rate is determined by propagation delay (16 ns max) and setup/hold timing of upstream drivers. For clean edge transitions, it reliably supports asynchronous data switching up to 40 MHz in systems with matched trace lengths and proper termination. The 76038012A maintains consistent behavior across its full –55°C to +125°C range without derating.

Does the 76038012A require external pull-up resistors on its outputs?

No, the 76038012A features totem-pole TTL outputs capable of sinking 24 mA and sourcing 0.4 mA, eliminating the need for external pull-ups in standard LS-TTL interfacing. Outputs drive directly into other TTL inputs or 50 Ω transmission lines with proper series termination. The 76038012A's output structure ensures valid logic levels across temperature without external biasing.

Is the 76038012A pin-compatible with commercial SN74LS258B variants?

No - the 76038012A uses a 20-pin LCCC (FK) package, while commercial SN74LS258B variants use 16-pin PDIP, SOIC, or CDIP packages. Pin count, layout, and thermal/mechanical interface differ fundamentally. Direct replacement requires PCB redesign. The 76038012A shares functional equivalence but not mechanical or pinout compatibility with any 16-pin variant.

What is the meaning of "NRND" status for the 76038012A, and does it affect reliability?

"NRND" (Not Recommended for New Designs) indicates Texas Instruments no longer promotes 76038012A for newly initiated projects, though it remains in production for existing qualified programs. Reliability is unaffected: the 76038012A retains full MIL-PRF-38535 Class V qualification, including burn-in and environmental stress screening. Aetrix Electronics guarantees supply continuity and traceable lot documentation for the 76038012A.

Can the 76038012A be used in space applications?

The 76038012A is qualified to MIL-PRF-38535 Class V for high-reliability defense use but is not radiation-hardened or screened to MIL-STD-883 Method 5005 (total ionizing dose) or Method 5007 (single-event effects). It is approved for airborne and ground-based military systems, not spaceflight. For space applications, TI's SN54LS257B-SP (space-grade variant) is the designated alternative - the 76038012A itself is not rated for orbital radiation environments.