Texas Instruments SN74LVC257APWRG4

Overview

SN74LVC257APWRG4 from Texas Instruments is a quadruple 2-line to 1-line data selector/multiplexer with 3-state outputs, designed for 1.65V–3.6V V_CC operation. It supports mixed-voltage interfacing (inputs tolerate up to 5.5V), delivers 4.6ns max propagation delay at 3.3V, and enables bus-organized signal routing in 4-bit data paths - widely used in I/O expanders and telecom infrastructure.

For engineers reviewing the SN74LVC257APWRG4 datasheet, SN74LVC257APWRG4 pinout, SN74LVC257APWRG4 application, or SN74LVC257APWRG4 equivalent, key selection criteria include its 16-pin TSSOP package, 3-state output enable control, voltage translation capability between 3.3V and 5V domains, and guaranteed latch-up immunity exceeding 250mA per JESD17.

Technical Context

The SN74LVC257APWRG4 implements four independent 2:1 multiplexers sharing a common active-low output-enable (OE) input and a global select line (A/B). Each channel routes either input A or B to its corresponding Y output based on the logic level of A/B, while OE controls high-impedance tri-state behavior across all four outputs simultaneously.

Its CMOS design supports rail-to-rail input tolerance (up to 5.5V regardless of V_CC), enabling seamless level translation in mixed-supply systems. The device features low ground bounce (<0.8V typical VOLP) and controlled undershoot (>2V typical VOHV) at 3.3V, ensuring signal integrity in high-speed digital buses.

Key Specifications

Pinout & Package

Packaged in a 16-pin TSSOP (PW), the SN74LVC257APWRG4 measures 5.00mm × 6.4mm with a body size of 5.00mm × 4.40mm and features gull-wing leads compatible with standard surface-mount reflow processes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC157APWR and 74LVC257PW,118, the SN74LVC257APWRG4 offers optimal balance of speed (4.6ns), industrial-grade reliability, and TI's long-term supply commitment - making it ideal for cost-sensitive, high-volume telecom and computing platforms requiring proven qualification and traceable sourcing.

Availability

SN74LVC257APWRG4 is available at Aetrix Electronics and suitable for cable modem termination systems, I/O expanders, and network switches requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for SN74LVC257APWRG4 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 and embedded processing technologies, with decades of experience delivering high-reliability logic, interface, and power management solutions.

The SN74LVC257A product line targets high-speed, low-voltage digital signal routing in space-constrained, mixed-supply systems - emphasizing voltage translation, bus isolation, and deterministic timing for telecom, computing, and industrial control applications.

FAQ

What is the maximum input voltage rating for SN74LVC257APWRG4?

The SN74LVC257APWRG4 supports input voltages up to 5.5V regardless of V_CC level, enabling safe interfacing with 5V logic families while operating from as low as 1.65V. This overvoltage tolerance is intrinsic to its input structure and does not require external clamping diodes or level-shifting circuitry. The SN74LVC257APWRG4 maintains full functionality and parametric compliance across its entire recommended V_CC range (1.65V–3.6V) under this condition.

Does SN74LVC257APWRG4 support true bidirectional signal routing?

No, the SN74LVC257APWRG4 is unidirectional: signals flow only from A/B inputs to Y outputs. Its I/O pins are internally configured as dedicated inputs (A/B, OE, A/B select) and outputs (Y), with no internal feedback path or bus transceiver architecture. While inputs tolerate 5.5V and outputs drive CMOS loads, the device cannot pass signals from Y back to A or B. For bidirectional applications, discrete switches or dedicated bus transceivers must be used instead of the SN74LVC257APWRG4.

What is the recommended bypass capacitor for SN74LVC257APWRG4?

A 0.1μF ceramic capacitor placed as close as possible to the V_CC pin is the recommended bypass solution for SN74LVC257APWRG4. This value is specified in TI's application guidance to suppress high-frequency noise and stabilize the supply during fast output transitions. The capacitor must be mounted directly between V_CC and GND with minimal trace length - ideally using a short, wide copper pour - to maintain low ESL and ensure effective decoupling at the device's 4.6ns switching edge rates. Larger bulk capacitors may supplement but do not replace this local 0.1μF requirement.

How does the OE pin behave during power-up sequences?

The OE pin of SN74LVC257APWRG4 is active-low and defaults to high-impedance output state when OE is high or floating. To ensure predictable high-impedance behavior during power-up, TI recommends tying OE to V_CC through a pull-up resistor - minimum value determined by the driver's sink capability. Without this, OE may float, causing undefined output states and potential bus contention. The SN74LVC257APWRG4 does not include internal power-on reset circuitry, so external biasing is essential for robust system initialization.

Is SN74LVC257APWRG4 RoHS compliant and lead-free?

Yes, SN74LVC257APWRG4 is RoHS compliant and features a lead-free NIPDAU (nickel/palladium/gold) terminal finish. Per TI's packaging documentation, it carries Level-1 moisture sensitivity rating with unlimited floor life under dry pack conditions and is qualified for standard 260°C peak reflow profiles. The "G4" suffix explicitly denotes green (halogen-free) and RoHS-compliant construction, verified through TI's material declaration and third-party testing protocols.