Texas Instruments SN74LVC257AQDRQ1

Overview

SN74LVC257AQDRQ1 from Texas Instruments is an automotive-qualified quadruple 2-line to 1-line data selector/multiplexer with 3-state outputs, operating from 2V to 3.6V supply, supporting 5.5V-tolerant inputs and delivering 4.6ns max propagation delay at 3.3V - used in bus multiplexing and level translation within automotive infotainment and body control modules.

For engineers reviewing the SN74LVC257AQDRQ1 datasheet, SN74LVC257AQDRQ1 pinout, SN74LVC257AQDRQ1 application, or SN74LVC257AQDRQ1 equivalent, this page delivers verified functional modes, validated WQFN/SOIC/TSSOP package mappings, confirmed 3.3V/5V interface compatibility, and real-world automotive timing and voltage margin data - all directly traceable to TI's SCAS709C production datasheet (May 2024 revision).

Technical Context

The SN74LVC257AQDRQ1 implements four independent 2:1 multiplexers sharing a common active-low output-enable (OE) input and a single select line (A/B), enabling simultaneous selection of either A or B inputs across all four channels. Each output drives a 3-state buffer capable of sinking or sourcing ±24mA at 3V.

Its logic-level translation capability arises from 5.5V-tolerant inputs while operating on a 2.7–3.6V VCC rail - allowing direct interfacing between legacy 5V logic and modern 3.3V microcontrollers without external level shifters. The device meets AEC-Q100 Grade 1 (–40°C to +125°C) requirements and exceeds 2000V HBM ESD protection.

Key Specifications

Pinout & Package

SN74LVC257AQDRQ1 is available in SOIC (D), TSSOP (PW), and WQFN (BQB) packages. This entry corresponds to the SOIC-16 variant (SN74LVC257ADRQ1), with 9.90 mm × 6.00 mm body size and 16-pin dual-in-line configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC157AQDRQ1, SN74LVC257AQDRQ1 adds 5.5V input tolerance and tighter propagation delay; versus SN74LVCH16257AQRHBRQ1, it offers smaller footprint and lower channel count - making SN74LVC257AQDRQ1 optimal for space-constrained automotive modules needing mixed-voltage interoperability.

Availability

SN74LVC257AQDRQ1 is available at Aetrix Electronics and suitable for automotive infotainment systems, body control modules, and instrument cluster designs requiring stable component supply, AEC-Q100 compliance, and long-term lifecycle support.

Supply support for SN74LVC257AQDRQ1 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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and automotive-grade silicon solutions.

The SN74LVC257AQDRQ1 belongs to TI's LVC logic family designed specifically for automotive applications requiring extended temperature range, high noise immunity, and reliable level translation between mixed-voltage subsystems.

FAQ

What is the maximum operating voltage for SN74LVC257AQDRQ1 inputs?

The SN74LVC257AQDRQ1 inputs tolerate voltages up to 5.5V regardless of VCC level - a key feature enabling direct interfacing with 5V logic in mixed-voltage automotive systems. This specification is explicitly defined in Section 4.3 (Recommended Operating Conditions) of the TI SCAS709C datasheet, and applies to all input pins including A/B, OE, and the eight data terminals (1A–4B). It does not extend to VCC or GND pins.

Does SN74LVC257AQDRQ1 support hot insertion or live swapping?

SN74LVC257AQDRQ1 is not rated for hot insertion. Its absolute maximum ratings specify VI ≤ 6.5V and VCC ≥ –0.5V, but the device lacks built-in bus-hold or power-up/down sequencing protection. TI recommends tying OE to VCC via a pull-up resistor during power-up to ensure outputs remain in high-impedance state until supply stabilizes - a practice documented in Section 6.1 of the datasheet to prevent bus contention during power transients.

What is the recommended bypass capacitor value for SN74LVC257AQDRQ1?

Texas Instruments specifies a 0.1-μF ceramic bypass capacitor placed as close as possible to the VCC pin of SN74LVC257AQDRQ1, per Section 7.1 of the SCAS709C datasheet. This value is required to suppress high-frequency noise and maintain stable supply voltage during fast output transitions. For boards with multiple VCC connections, TI advises using 0.01–0.022-μF capacitors per terminal, and permits paralleling multiple values to target different noise frequencies.

How does the A/B select pin function across all four multiplexers in SN74LVC257AQDRQ1?

The A/B pin is a shared select control for all four 2:1 multiplexers inside SN74LVC257AQDRQ1. When A/B is low, each Y output routes its corresponding A input (1Y = 1A, 2Y = 2A, etc.); when high, it routes the B input (1Y = 1B, 2Y = 2B, etc.). This synchronous behavior is confirmed in the Function Table (Section 6.3) and Logic Diagram (Figure 6-1) of the TI datasheet, and enables coordinated channel selection without requiring separate control lines.

Is SN74LVC257AQDRQ1 pin-compatible with SN74LVC257A (non-Q1)?

Yes, SN74LVC257AQDRQ1 is pin-compatible with the commercial-grade SN74LVC257A across all package variants (SOIC, TSSOP, WQFN), as confirmed by identical pin configurations in Figures 3-1 and 3-2 of the SCAS709C datasheet. The Q1 suffix denotes automotive qualification (AEC-Q100 Grade 1, enhanced ESD, extended temperature), but electrical pin functions, numbering, and mechanical footprints remain unchanged - enabling drop-in replacement in existing designs requiring automotive reliability.