Texas Instruments SN74LS258BDR

Overview

SN74LS258BDR from Texas Instruments is a quadruple 2-line to 1-line data selector/multiplexer in SOIC-16 package, operating over 0°C to 70°C, with typical propagation delay of 15 ns at V_CC = 5 V and I_OL = 8 mA, used for digital signal routing in legacy TTL-based control logic and bus arbitration circuits.

For engineers reviewing the SN74LS258BDR datasheet, SN74LS258BDR pinout, SN74LS258BDR application, or SN74LS258BDR equivalent, this page delivers verified functional identity, confirmed pin mapping, real-world timing specs, industrial temperature-grade alternatives, and supply-chain-ready procurement details - all specific to the SN74LS258BDR variant.

Technical Context

The SN74LS258BDR implements four independent 2:1 multiplexers sharing a common select (S) and output enable (G̅) control, each selecting between two data inputs (A_n, B_n) to drive one output (Y_n). All logic operates in standard LS-TTL voltage thresholds and fan-out capability.

It features complementary active-low output enable (G̅), enabling simultaneous disabling of all four outputs to high-impedance state, and uses bipolar transistor-transistor logic (TTL) architecture with Schottky-clamped outputs for improved speed and noise immunity over standard 74-series devices.

Key Specifications

Pinout & Package

SN74LS258BDR is housed in a 16-pin Small Outline Integrated Circuit (SOIC) package with 1.27 mm pitch, 7.5 mm body width, and 2.00 mm max height per TI drawing NS0016A.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LS257BDR and SN74LS157N, the SN74LS258BDR provides non-inverted outputs in a RoHS-compliant, surface-mount SOIC package optimized for modern automated production - making it the preferred choice for new commercial-grade designs requiring direct signal routing without polarity inversion or through-hole constraints.

Availability

SN74LS258BDR is available at Aetrix Electronics and suitable for industrial control logic, digital test equipment, legacy bus arbitration, and embedded instrumentation front-end applications requiring stable component supply and long-term obsolescence management.

Supply support for SN74LS258BDR 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 logic ICs with broad industrial, automotive, and aerospace product portfolios.

The SN74LS258BDR belongs to TI's legacy 74LS logic family, designed specifically for backward-compatible upgrades and maintenance of commercial-grade TTL-based digital systems requiring reliable, low-speed signal routing.

FAQ

What is the primary function of the SN74LS258BDR?

The SN74LS258BDR is a quadruple 2-line to 1-line data selector/multiplexer that routes four independent pairs of digital inputs (A_n/B_n) to corresponding outputs (Y_n) under shared select (S) and output enable (G̅) control. Its non-inverting outputs and LS-TTL compatibility make SN74LS258BDR ideal for signal routing in legacy digital systems where deterministic timing and direct interface with 74LS logic are required.

Does the SN74LS258BDR support 3.3 V operation?

No, the SN74LS258BDR is specified only for 5 V ±5% operation (4.75 V to 5.25 V). It uses standard LS-TTL input thresholds (VIH = 2.0 V min, VIL = 0.8 V max) and output drive characteristics designed for 5 V systems. Using SN74LS258BDR with 3.3 V supply risks undefined logic states, insufficient noise margin, and potential damage due to internal biasing - always operate SN74LS258BDR at its rated 5 V supply.

How does the output enable (G̅) pin function on the SN74LS258BDR?

The G̅ pin on SN74LS258BDR is an active-low output enable that places all four Y_n outputs into high-impedance state when driven HIGH, regardless of S or input states. When G̅ is LOW, the device performs normal 2:1 multiplexing per channel based on the S input. This feature allows SN74LS258BDR to share buses or isolate signal paths without external gating logic.

Is the SN74LS258BDR pin-compatible with the SN74LS257BDR?

Yes, SN74LS258BDR and SN74LS257BDR share identical pinout and package (SOIC-16), but differ in output polarity: SN74LS258BDR provides true (non-inverted) outputs, while SN74LS257BDR provides complemented (inverted) outputs. Therefore, SN74LS258BDR is not a functional drop-in replacement unless downstream logic accommodates the polarity difference - always verify signal polarity requirements before substituting SN74LS258BDR for SN74LS257BDR.

What is the maximum recommended clock/data rate for reliable operation of the SN74LS258BDR?

The SN74LS258BDR has a maximum propagation delay of 15 ns (t_PLH/t_PHL) under standard load conditions (C_L = 15 pF, V_CC = 5 V). This supports reliable operation up to approximately 33 MHz in non-critical timing paths, though system-level setup/hold margins and trace routing should be validated. For synchronous applications, SN74LS258BDR is typically used below 10 MHz to ensure robust timing closure - especially when interfacing with microcontrollers or FPGAs lacking precise skew control.