Texas Instruments SN74ALS541NSRG4

Overview

SN74ALS541NSRG4 from Texas Instruments is an octal buffer and line driver with 3-state outputs, designed for bus interfacing and memory address register buffering in TTL-compatible digital systems. It features true (non-inverting) data flow, dual 3-state enable inputs (OE1/OE2), and supports 24 mA low-level output drive at V_CC = 4.5 V - enabling direct connection to standard TTL loads without external pull-ups.

For engineers reviewing the SN74ALS541NSRG4 datasheet, SN74ALS541NSRG4 pinout, SN74ALS541NSRG4 application, or SN74ALS541NSRG4 equivalent, key selection criteria include its 20-pin SSOP package, pnp-input architecture reducing DC loading, data flowthrough pinout (inputs and outputs on opposite sides), and compatibility with legacy ALS logic families in industrial control and embedded bus architectures.

Technical Context

This device implements a dual-NOR 3-state control gate: either OE1 or OE2 high forces all eight Y outputs into high-impedance mode. Its pnp input structure lowers input current draw versus standard TTL, improving fan-out capability in dense logic systems.

Designed as a functional and pinout-optimized successor to SN74ALS240A, the SN74ALS541NSRG4 provides true (non-inverted) output logic with identical timing performance - t_PLH/t_PHL ≤ 14 ns at V_CC = 4.5–5.5 V and C_L = 50 pF - while separating inputs (pins 1–8, 19–20) and outputs (pins 11–18) across the package for simplified PCB routing.

Key Specifications

Pinout & Package

SN74ALS541NSRG4 is housed in a 20-pin Small Outline Package (SSOP), DB package type, with 0.65 mm lead pitch and 7.5 mm × 5.6 mm body size. The package supports surface-mount assembly with moisture sensitivity level (MSL) 1 and peak reflow up to 260°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ALS541NSRG4, the PDIP version offers easier manual soldering but lower board density, while the SOIC variant trades compactness for broader assembly infrastructure support - all three share identical ALS logic behavior and timing.

Availability

SN74ALS541NSRG4 is available at Aetrix Electronics and suitable for industrial control backplanes, legacy memory subsystems, automated test equipment, and embedded instrumentation requiring stable component supply and long-term obsolescence management.

Supply support for SN74ALS541NSRG4 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 global semiconductor leader founded in 1930, specializing in analog, embedded processing, and logic solutions with broad industrial, automotive, and aerospace qualification.

The SN74ALS541NSRG4 belongs to TI's legacy Advanced Low-Power Schottky (ALS) logic family, engineered for high-speed, low-power TTL-compatible interfacing in mission-critical industrial and military-grade systems.

FAQ

What is the maximum output sink current supported by the SN74ALS541NSRG4?

The SN74ALS541NSRG4 supports a guaranteed low-level output current (I_OL) of 24 mA per channel at V_CC = 4.5 V, as specified in the recommended operating conditions table. This rating ensures reliable drive into standard TTL loads without external components. The -1 variant (e.g., SN74ALS541-1NSR) supports 48 mA, but SN74ALS541NSRG4 is the standard version and does not include this enhanced rating.

Does the SN74ALS541NSRG4 support inverted or true data output?

The SN74ALS541NSRG4 provides true (non-inverting) data output - A1–A8 inputs appear unchanged at Y1–Y8 outputs when enabled. This distinguishes it from the SN74ALS540 series, which delivers inverted outputs. The 'ALS541 designation explicitly indicates true logic polarity, confirmed in the device description and logic diagrams of the SDAS025D datasheet.

What is the function of the two output-enable inputs (OE1 and OE2) on the SN74ALS541NSRG4?

The SN74ALS541NSRG4 uses a 2-input NOR gate for 3-state control: if either OE1 or OE2 is driven high, all eight outputs enter high-impedance mode. Both enables must be low for normal output operation. This architecture allows flexible bus arbitration - for example, OE1 can serve as primary enable while OE2 acts as fault-safety override in safety-critical systems.

Is the SN74ALS541NSRG4 pin-compatible with the SN74ALS240A?

No, the SN74ALS541NSRG4 is not pin-compatible with SN74ALS240A. While both are octal 3-state buffers in the ALS family, SN74ALS541NSRG4 uses a data flowthrough pinout (inputs and outputs on opposite sides), whereas SN74ALS240A has interleaved I/O. However, SN74ALS541NSRG4 was designed to match SN74ALS240A's electrical and timing performance - making it a functional upgrade requiring PCB layout revision.

What package type and dimensions does the SN74ALS541NSRG4 use?

The SN74ALS541NSRG4 uses a 20-pin Small Outline Package (SSOP), designated DB package, with 0.65 mm lead pitch, 7.5 mm × 5.6 mm body size, and maximum height of 2.0 mm. Its land pattern follows JEDEC MO-150, and it is rated MSL-1 for reflow up to 260°C - confirmed in TI's DB0020A package outline and tape-and-reel documentation.