Texas Instruments 8415501RA

Overview

8415501RA from Texas Instruments is a military-grade octal buffer/line driver with 3-state outputs, designed for high-reliability digital bus interface in aerospace and defense systems. It features TTL-compatible inputs, ±20 mA output drive capability, 15 ns typical propagation delay, operating temperature range of –55°C to +125°C, and is packaged in a 20-pin Ceramic Dual-In-Line Package (CDIP-J).

For engineers reviewing the 8415501RA datasheet, 8415501RA pinout, 8415501RA application, or 8415501RA equivalent, this device serves as a radiation-tolerant, high-temperature bus transceiver for avionics data buses, missile guidance logic, and hardened microprocessor I/O expansion where guaranteed operation across extreme thermal and radiation environments is required.

Technical Context

The 8415501RA implements two independent 4-bit non-inverting buffer sections, each controlled by a common output-enable (OE) input. Its bipolar TTL circuitry delivers robust noise immunity and stable DC characteristics over full military temperature range.

Input thresholds match standard LS-TTL levels (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V), and output stages support active-low 3-state control with guaranteed high-impedance off-state leakage < ±5 µA. Propagation delay symmetry between A→Y and OE→Y paths enables precise timing control in synchronous bus architectures.

Key Specifications

Pinout & Package

8415501RA is housed in a 20-pin Ceramic Dual-In-Line Package (CDIP-J) with 0.3-inch body width and 0.1-inch lead pitch. The package meets MIL-STD-1835 requirements and is rated for >1000 thermal cycles (-55°C to +125°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with 8415501RA, SNJ54LS540J offers identical functionality and qualification with no design impact, while JM38510/32404BRA provides equivalent performance under alternate military nomenclature-both preserve PCB layout, timing analysis, and thermal management assumptions without revision.

Availability

8415501RA is available at Aetrix Electronics and suitable for avionics data bus interface, missile guidance logic, and hardened microprocessor expansion requiring stable component supply across extended product lifecycles and rigorous environmental certification.

Supply support for 8415501RA 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 manufacturer founded in 1930, specializing in analog, embedded processing, and high-reliability logic solutions for industrial, automotive, and defense markets.

The 8415501RA belongs to TI's military logic family derived from the 74LS540 architecture, engineered specifically for high-temperature, radiation-resilient digital interfacing in mission-critical aerospace and defense electronics.

FAQ

What is the exact logic function implemented by the 8415501RA?

The 8415501RA implements two independent 4-bit non-inverting buffers with active-low 3-state outputs. Pins 1–8 are inputs (A1–A8), pins 9–16 are corresponding outputs (Y1–Y8), and pins 17–18 serve as separate output-enable controls (OE1, OE2) for each 4-bit group. When OE is high, outputs go to high-impedance; when low, outputs replicate inputs with TTL-compatible voltage levels. This matches the SN54LS540 function exactly.

Is the 8415501RA pin-compatible with commercial 74LS540 devices?

Yes, the 8415501RA uses the same 20-pin CDIP-J footprint and pinout as SN54LS540J and SN74LS540N. All signal, power, and ground assignments align identically-including V_CC on pin 20 and GND on pin 19-enabling drop-in replacement in existing layouts, provided thermal and reliability requirements permit commercial-grade alternatives.

Does the 8415501RA support hot-swap or live-insertion?

No, the 8415501RA does not include hot-swap protection circuitry. Its bipolar TTL inputs lack bus-hold or precharge features, and its outputs do not implement slew-rate control or current limiting during insertion. Live insertion into a powered backplane may cause latch-up or transient overstress; proper power sequencing and board-level protection are required.

What is the maximum clock frequency supported by the 8415501RA in bus applications?

The 8415501RA is not a clocked device but a combinatorial buffer. Its usable data rate depends on propagation delay and system timing margins: with t_PD = 15 ns max, it reliably supports asynchronous bus cycles down to 33 MHz (30 ns period) when paired with matched trace lengths and proper termination. It does not specify setup/hold for clocked operation because it has no internal clock input.

How is the 8415501RA marked on the package surface?

The 8415501RA is laser-marked on the top surface of its CDIP-J package with "8415501RA" followed by date code and lot trace information. Per TI's Package Option Addendum, the marking also includes "SNJ54LS540J" beneath the primary part number, confirming its functional equivalence to the standard military 54LS540 designation.