Nexperia USA Inc. 74HCT257D-Q100J

Overview

74HCT257D-Q100 from Nexperia is an automotive-qualified quad 2-input multiplexer with 3-state outputs, TTL-compatible input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V at VCC = 4.5–5.5 V), 16-pin SO16 package, and AEC-Q100 Grade 1 qualification (−40 °C to +125 °C). It routes one of two data sources per channel to a shared bus in engine control units, body electronics, and ADAS sensor interfaces.

For engineers reviewing the 74HCT257D-Q100 datasheet, 74HCT257D-Q100 pinout, 74HCT257D-Q100 application, or 74HCT257D-Q100 equivalent, key selection criteria include TTL-level input compatibility, 3-state bus interface capability, propagation delay ≤ 45 ns at 4.5 V, enable/disable timing under 45 ns, and automotive-grade thermal and ESD robustness (HBM > 2000 V, CDM > 1000 V).

Technical Context

This device implements four independent 2:1 multiplexers sharing a common select (S) and active-low output enable (OE) control line. Each channel selects between I0 and I1 inputs based on S, driving its Y output only when OE is low - enabling direct connection to bidirectional system buses without external buffering.

Input clamp diodes allow safe interfacing with voltages exceeding VCC when used with current-limiting resistors. The CMOS output stage delivers rail-to-rail VOH/VOL performance (VOH ≥ 3.98 V, VOL ≤ 0.26 V at IO = ±6 mA, VCC = 4.5 V) across the full −40 °C to +125 °C operating range.

Key Specifications

Pinout & Package

74HCT257D-Q100 uses the SOT109-1 (SO16) plastic small outline package: 16-pin, 3.9 mm body width, 1.27 mm lead pitch, gull-wing leads, RoHS-compliant, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HC257D-Q100, the 74HCT257D-Q100 provides guaranteed TTL input compatibility essential for legacy automotive modules, while SN74LV257AQPWRQ1 offers broader supply adaptability at a modest speed trade-off - making the HCT variant optimal for pure 5 V TTL-legacy integration.

Availability

74HCT257D-Q100 is available at Aetrix Electronics and suitable for engine control units, body electronics modules, ADAS sensor fusion nodes, and instrument cluster systems requiring stable component supply across automotive production lifecycles.

Supply support for 74HCT257D-Q100 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 focused on high-volume, high-reliability logic, discrete, and MOSFET solutions, with leadership in automotive-qualified components.

The 74HCT257-Q100 belongs to Nexperia's automotive logic portfolio, designed specifically to replace legacy 74-series TTL multiplexers in safety-critical vehicle subsystems while meeting AEC-Q100 stress test requirements.

FAQ

Is 74HCT257D-Q100 pin-compatible with non-automotive 74HCT257 variants?

Yes - the 74HCT257D-Q100 shares identical pinout, electrical behavior, and functional logic with standard 74HCT257 devices in SO16 packaging. The Q100 suffix denotes AEC-Q100 qualification and extended temperature screening, not physical or logical differences. All timing, voltage, and drive specifications match the industrial-grade counterpart under the same operating conditions.

Can OE and S be driven by the same microcontroller GPIO?

Yes - OE (active-low) and S (data select) are fully static CMOS inputs with II ≤ ±1 μA at 25 °C. A single GPIO can drive both via appropriate logic inversion (e.g., OE = NOT(SWITCH_MODE), S = SWITCH_SELECT), provided timing constraints (tpd, ten, tdis) are met. No additional buffering is required for typical MCU output drive strength.

What is the maximum capacitive load each Y output can drive reliably?

Each 3-state Y output drives up to 15 pF with guaranteed timing (tpd ≤ 45 ns, tt ≤ 18 ns at VCC = 4.5 V). For loads exceeding 15 pF, propagation delay increases linearly - e.g., 30 pF adds ~12 ns to tpd. Layout best practices (short traces, ground plane) are essential to maintain signal integrity in high-noise automotive environments.

Does the device support hot insertion or live bus connection?

No - 74HCT257D-Q100 is not hot-plug rated. Its absolute maximum ratings specify VI and VO limits relative to GND and VCC; applying voltage to any pin before VCC stabilization risks latch-up or ESD damage. Power sequencing must ensure VCC is stable before asserting OE or S, and all inputs remain within [0 V, VCC] during power-up/down.