Texas Instruments SN74HC257PWRG4

Overview

SN74HC257PWRG4 from Texas Instruments is a quadruple 2-line to 1-line data selector/multiplexer with non-inverted 3-state outputs, operating across 2 V to 6 V supply range. It features 9 ns typical propagation delay at 4.5 V, ±6 mA output drive, 80 µA max ICC, and supports bus interface in high-performance digital systems.

For engineers reviewing the SN74HC257PWRG4 datasheet, SN74HC257PWRG4 pinout, SN74HC257PWRG4 application, or SN74HC257PWRG4 equivalent, key selection criteria include its 16-pin TSSOP package, 3-state enable control (G), dual-input per channel (A/B), non-inverting output logic, and compatibility with LSTTL loads in space-constrained logic interfacing designs.

Technical Context

The SN74HC257PWRG4 implements four independent 2:1 multiplexers sharing common address (A/B) and active-low output-enable (G) inputs. All outputs enter high-impedance state when G is high, enabling bidirectional bus arbitration without external gating.

Its CMOS HC-family architecture ensures low static current (≤1 µA input leakage), rail-to-rail output swing, and robust noise immunity-critical for mixed-voltage system interconnects where signal integrity and power efficiency are jointly constrained.

Key Specifications

Pinout & Package

TSSOP-16 package (5.00 mm × 4.40 mm, 1.2 mm max height), lead-free (NIPDAU), moisture sensitivity level 1, RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 2:1 multiplexer applications.

Compared with SN74HC157DR and 74LVC157APW, SN74HC257PWRG4 uniquely balances wide-voltage operation (2–6 V), TSSOP-16 compactness, and proven 9 ns timing-making it optimal for mixed-supply industrial and automotive control boards where pin compatibility and legacy voltage support are mandatory.

Availability

SN74HC257PWRG4 is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, test equipment signal routing, and medical device sensor interfaces requiring stable component supply across extended temperature ranges (−40°C to +85°C).

Supply support for SN74HC257PWRG4 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 specializing in analog, embedded processing, and logic solutions, with over 50 years of innovation in high-reliability digital ICs.

The SN74HC257PWRG4 belongs to TI's HC logic family, designed specifically for low-power, wide-voltage-range bus interfacing and signal routing in industrial, automotive, and instrumentation applications.

FAQ

What is the maximum operating frequency supported by SN74HC257PWRG4?

The SN74HC257PWRG4 does not specify a maximum clock frequency, but its 9 ns typical propagation delay at 4.5 V implies reliable operation in data paths with signal periods >25 ns (i.e., up to ~40 MHz). System-level timing must account for worst-case tpd (25 ns), enable/disable times, and PCB trace delays. For guaranteed timing closure, design margins should target ≤20 MHz in noise-prone environments.

Can SN74HC257PWRG4 operate at 3.3 V and interface directly with 5 V logic?

Yes, SN74HC257PWRG4 operates from 2 V to 6 V, so 3.3 V is within spec. Its outputs swing rail-to-rail, providing VOH ≈ 3.3 V and VOL ≈ 0 V at 3.3 V supply-compatible with 3.3 V inputs. For 5 V-tolerant inputs, external level-shifting is required since SN74HC257PWRG4 inputs are not 5 V tolerant above VCC.

Is SN74HC257PWRG4 pin-compatible with SN74HC157?

Yes, SN74HC257PWRG4 is functionally and pin-compatible with SN74HC157 in TSSOP-16 (PW) and SOIC-16 (D) packages. Both share identical pin assignments: G on pin 1, Y1–Y4 on pins 4/7/12/15, A/B pairs on pins 2–3/5–6/10–11/13–14, VCC on pin 16, and GND on pin 8. The '257 suffix denotes TI's standard ordering variant.

What is the recommended bypass capacitor for SN74HC257PWRG4?

Texas Instruments recommends a 0.1 µF ceramic capacitor placed as close as possible (≤2 mm) to the VCC (pin 16) and GND (pin 8) pins of SN74HC257PWRG4. For improved high-frequency noise suppression, this may be paralleled with a 1 µF tantalum or ceramic capacitor. Avoid long traces or vias between the capacitor and IC pins to maintain low impedance at switching frequencies.

Does SN74HC257PWRG4 require pull-up resistors on unused inputs?

Yes, all unused inputs-including A, B, and G-must be tied to VCC or GND to prevent floating states that cause excessive ICC, oscillation, or undefined outputs. For G, a pull-up resistor to VCC is strongly recommended to ensure outputs remain in high-impedance during power-up/down sequences and avoid bus contention.