Texas Instruments SN74LS241NSR

Overview

SN74LS241NSR from Texas Instruments is an octal non-inverting buffer/line driver with dual 4-bit channels and independent 3-state output-enable (G) inputs, designed for memory address and bus driving in TTL systems. It features PNP inputs reducing DC loading, 400-mV noise margin via input hysteresis, and 15 ns maximum propagation delay at 5 V. It drives terminated lines down to 133 Ω and supports mixed-voltage interfacing with 3.3-V/2.5-V logic-compatible inputs.

For engineers reviewing the SN74LS241NSR datasheet, SN74LS241NSR pinout, SN74LS241NSR application, or SN74LS241NSR equivalent, key selection criteria include its dual-channel 3-state control architecture, LS-family drive strength (24 mA sink), thermal performance in SOP-20 (RθJA = 76.6°C/W), and compatibility with legacy TTL and mixed-supply bus systems.

Technical Context

The SN74LS241NSR implements two independent 4-bit non-inverting buffers, each with active-low output-enable (1G and 2G/2G). When G is low, data passes from A-side inputs (1A1–1A4, 2A1–2A4) to Y-side outputs (1Y1–1Y4, 2Y1–2Y4); when G is high, outputs enter high-impedance state. Inputs tolerate down to 2 V, enabling interoperability with 3.3-V logic sources.

It uses Schottky-clamped bipolar TTL (LS) technology, delivering 24 mA low-level output current and –15 mA high-level output current at VCC = 5 V. Input hysteresis (0.2–0.4 V) improves noise immunity on shared bus lines, while PNP input structure minimizes DC loading on upstream drivers.

Key Specifications

Pinout & Package

SN74LS241NSR is supplied in a 20-pin SOP (Small Outline Package) with body size 7.80 mm × 12.60 mm, designated NS package per TI documentation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal non-inverting buffer applications.

Compared with SN74LS244NSR and SN74ALS241NSR, the SN74LS241NSR offers unique dual-channel independent enable control and proven thermal behavior in SOP-20, making it optimal for mixed-control bus architectures where channel-specific timing isolation is required.

Availability

SN74LS241NSR is available at Aetrix Electronics and suitable for memory address buffering, LED display multiplexing, and industrial I/O expansion requiring stable component supply and long-term industrial lifecycle support.

Supply support for SN74LS241NSR 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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and logic ICs for industrial, automotive, and communications markets.

The SN74LS241NSR belongs to TI's legacy LS-TTL logic family, engineered for robust bus driving, memory interfacing, and noise-immune signal conditioning in mission-critical industrial control and telecom infrastructure.

FAQ

What is the function of pin 19 (2G/2G) on the SN74LS241NSR?

Pin 19 is the active-low output-enable input for channel 2. When driven low, it enables non-inverting data flow from inputs 2A1–2A4 to outputs 2Y1–2Y4; when high, all 2Y outputs enter high-impedance state. Its labeling as "2G/2G" reflects dual-symbol notation in TI's logic diagrams for consistent active-low representation. This control is fully independent of pin 1 (1G).

Does the SN74LS241NSR support 3.3-V input logic levels?

Yes, the SN74LS241NSR inputs tolerate down to 2 V and are explicitly compatible with 3.3-V and 2.5-V logic sources per TI's datasheet. This allows direct connection to modern microcontrollers or FPGAs without level-shifting circuitry, while maintaining full TTL output swing (VOH ≥ 2.4 V, VOL ≤ 0.5 V) at VCC = 5 V.

What is the maximum output current rating for SN74LS241NSR outputs?

The SN74LS241NSR provides 24 mA maximum sink current (IOL) per output at VCC = 5 V and TA = 25°C, and –15 mA maximum source current (IOH). These values are specified under Recommended Operating Conditions and define safe steady-state drive capability into TTL loads or terminated lines without exceeding thermal limits in the NS package.

Can SN74LS241NSR be used in place of SN74LS244NSR?

No - although both are octal non-inverting buffers in SOP-20, the SN74LS241NSR has independent 1G and 2G enables (active-low), whereas SN74LS244NSR uses identical active-low enables for both channels. Their pinouts differ: SN74LS241NSR places 2Y outputs on pins 3,5,7,9 and 1Y on 12,14,16,18; SN74LS244NSR groups all Y outputs contiguously. Direct substitution is not possible without PCB redesign.

What thermal derating applies to SN74LS241NSR in SOP-20 package?

The SN74LS241NSR in NS (SOP-20) package has RθJA = 76.6°C/W. At 5 V and full output loading (24 mA × 8 outputs), total power dissipation may reach ~120 mW, resulting in ~9.2°C junction-to-ambient rise above ambient. For continuous operation at 70°C ambient, junction temperature remains within 125°C limit. Derating is required above 70°C ambient per TI's thermal guidelines.