Nexperia USA Inc. 74AHCT257PW,118

Overview

74AHCT257PW,118 from Nexperia is a quad 2-input multiplexer with 3-state outputs and TTL-compatible input thresholds, operating from 4.5 V to 5.5 V supply. It features overvoltage-tolerant inputs (up to 5.5 V), Schmitt-trigger inputs for noise immunity, and supports mixed-voltage signal routing in industrial control logic. Its 16-pin TSSOP package enables high-density PCB layout in data path selection circuits.

For engineers reviewing the 74AHCT257PW,118 datasheet, 74AHCT257PW,118 pinout, 74AHCT257PW,118 application, or 74AHCT257PW,118 equivalent, key selection criteria include TTL-level input compatibility, 3-state output enable timing (t_en ≤ 12.0 ns at V_CC = 5.5 V), propagation delay (t_pd ≤ 9.0 ns), and operation across −40 °C to +125 °C industrial temperature range.

Technical Context

This device implements four independent 2:1 multiplexers sharing a common select line (S) and active-low output enable (OE). Each channel routes one of two digital inputs (nI0/nI1) to its corresponding 3-state output (nY), enabling dynamic bus arbitration or signal source switching.

All inputs accept TTL voltage levels (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V at V_CC = 4.5–5.5 V), while outputs drive CMOS loads with VOH ≥ 3.70 V and VOL ≤ 0.55 V at 8 mA sink/source, ensuring interoperability with legacy 5 V logic families.

Key Specifications

Pinout & Package

TSSOP16 plastic thin shrink small outline package (SOT403-1); 16 leads; body width 4.4 mm; lead pitch 0.65 mm; RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input multiplexer applications.

Compared with SN74LV257APW and 74HC257PW, the 74AHCT257PW,118 uniquely guarantees robust TTL-level recognition without external components, making it the sole drop-in solution for legacy 5 V controller interfaces requiring guaranteed 2.0 V V_IH and 0.8 V V_IL thresholds.

Availability

74AHCT257PW,118 is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, legacy microcontroller bus multiplexing, and automated test equipment signal routing requiring stable component supply across extended temperature ranges.

Supply support for 74AHCT257PW,118 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

Nexperia is a global semiconductor expert delivering high-performance logic, analog, and MOSFET solutions optimized for efficiency, reliability, and manufacturability in high-volume applications.

The 74AHCT series targets industrial and automotive-adjacent logic interfacing, designed specifically to bridge legacy TTL systems with modern CMOS-based controllers while maintaining robust noise immunity and wide temperature operation.

FAQ

What is the maximum clock frequency supported by the 74AHCT257PW,118?

The device does not operate on a clock; it is combinational logic. However, its propagation delay (t_pd ≤ 9.0 ns at V_CC = 5.5 V, CL = 50 pF) supports reliable data selection at effective rates up to ~110 MHz in synchronous systems where S and OE are toggled at that rate. Timing margins must account for setup/hold relative to control edges.

Can the 74AHCT257PW,118 be used with a 3.3 V supply?

No - the 74AHCT257PW,118 is specified only for 4.5 V to 5.5 V operation. Using 3.3 V violates recommended conditions and results in undefined input recognition (V_IH minimum is 2.0 V, but VIH/VIL ratios collapse below V_CC = 4.5 V), risking logic errors. Use 74AHC257PW for 3.3 V systems.

How does the overvoltage tolerance benefit system design?

Inputs tolerate up to 5.5 V regardless of V_CC, allowing direct connection to 5 V sensors, switches, or open-drain buses even when V_CC = 4.5 V. This eliminates external clamping diodes or resistive dividers, reducing BOM cost and PCB area while preserving signal integrity and edge speed.

Is the 74AHCT257PW,118 pin-compatible with the 74AHC257PW?

Yes - both share identical TSSOP16 (SOT403-1) pinout and footprint. However, they differ electrically: 74AHC257PW requires CMOS-level inputs (V_IH ≥ 3.85 V at 5.5 V), while 74AHCT257PW accepts TTL levels (V_IH ≥ 2.0 V). Swapping them may cause functional failure if driving sources lack sufficient HIGH voltage margin.