Texas Instruments SN74F151BN

Overview

SN74F151BN from Texas Instruments is an 8-line to 1-line TTL multiplexer with active-low strobe enable, 3-bit binary address decoding (A/B/C), complementary W and Y outputs, and operation over 0°C to 70°C. It selects one of eight data inputs (D0–D7) based on address lines and drives both true (Y) and inverted (W) outputs simultaneously. Used in digital logic systems for data routing, Boolean function generation, and parallel-to-serial conversion.

For engineers reviewing the SN74F151BN datasheet, SN74F151BN pinout, SN74F151BN application, or SN74F151BN equivalent, key selection criteria include its 16-pin PDIP package, guaranteed 24 mA low-level output drive, 5 V supply compatibility, and dual-output (Y/W) architecture supporting combinational logic synthesis without external inverters.

Technical Context

The SN74F151BN implements full binary decoding of three select inputs (A, B, C) to route one of eight data inputs to the Y output while asserting the complement on W. Its strobe (G) input enables or disables the multiplexing function: G = L enables selection; G = H forces Y = L and W = H regardless of address or data states.

Designed for TTL-compatible systems, it features standard F-series propagation delays (tPLH/tPHL ≤ 12 ns at VCC = 5 V, CL = 50 pF), supports 20–24 mA sink current per output, and operates within strict 4.5–5.5 V supply range - ensuring interoperability with legacy 74F logic families and predictable timing in synchronous control paths.

Key Specifications

Pinout & Package

SN74F151BN uses a 16-pin plastic dual in-line package (PDIP) with 0.3-inch body width and standard DIP footprint (10.4 mm × 6.35 mm). Pin 1 is marked by a notch or dot; leads are tin-lead (NIPDAU) finished and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8:1 multiplexer applications.

Compared with SN74LS151N and SN74HC151N, the SN74F151BN delivers superior output drive and speed for TTL-centric systems, making it the optimal choice when interfacing with legacy controllers, LED indicators, or multi-load buses - without requiring redesign of existing 5 V supply or signal integrity margins.

Availability

SN74F151BN is available at Aetrix Electronics and suitable for industrial control panels, legacy test equipment upgrades, and educational lab kits requiring stable component supply and long-term obsolescence management.

Supply support for SN74F151BN 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 solutions with broad industrial and automotive reach.

The SN74F151BN belongs to TI's 74F family of fast TTL logic devices, engineered for high-speed digital systems requiring predictable timing, robust noise margins, and backward compatibility with earlier 74-series logic in commercial temperature environments.

FAQ

What is the maximum clock frequency supported by SN74F151BN in a data-select application?

The SN74F151BN does not operate on a clock signal - it is asynchronous. Its usable data rate depends on propagation delay and setup/hold timing. With tPHL/tPLH ≤ 12 ns and address stability maintained ≥1 ns before G assertion, SN74F151BN reliably supports data selection cycles up to approximately 80 MHz in well-designed layouts. For precise timing, always reference the SN74F151BN switching characteristics table under CL = 50 pF conditions.

Can SN74F151BN drive LEDs directly without current-limiting resistors?

No - SN74F151BN must always use external current-limiting resistors when driving LEDs. Although it supports 24 mA sink current per output, forward voltage and LED characteristics vary. For a typical red LED (VF ≈ 1.8 V), a 150 Ω resistor at 5 V ensures ~21 mA drive while staying within SN74F151BN absolute max ratings. Omitting the resistor risks exceeding IOL limits and damaging the SN74F151BN output stage.

Is SN74F151BN pin-compatible with SN74LS151N?

Yes - SN74F151BN and SN74LS151N share identical 16-pin PDIP (N) packaging, pin numbering, and functional pin assignments (D0–D7, A–C, G, Y, W, VCC, GND). However, due to differing drive strength and timing, direct substitution may affect system timing margins or fanout capability. Always verify loading and propagation delay impact when replacing SN74LS151N with SN74F151BN in existing designs.

Does SN74F151BN support 3.3 V logic interfaces?

No - SN74F151BN is specified only for 4.5–5.5 V operation and TTL input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V). While it may function marginally at 3.3 V, parameters like VOH, VOL, and switching speed are not guaranteed outside the recommended 5 V range. For 3.3 V systems, use SN74LVC151A or similar CMOS alternatives instead of SN74F151BN.

How does the strobe (G) input affect output behavior when high?

When the strobe input G is high, the SN74F151BN disables data selection entirely: output Y is forced low and output W is forced high, regardless of address (A/B/C) or data (D0–D7) states. This override function allows global output blanking, hierarchical enable control in multi-stage mux trees, or safe-state assertion during reset or fault conditions - all without altering address or data bus values.