Diodes Incorporated PI3B3257AQE

Overview

PI3B3257AQE from Diodes Incorporated is a 3.3 V quad 2:1 multiplexer/demultiplexer with three-state outputs, pinout- and function-compatible with 74F257, 74ALS257, and PI74FCT257T. It features 5 Ω on-resistance, 4.8 ns max propagation delay, and 0.1 µA typical quiescent current, enabling low-noise signal routing in notebook and portable logic systems.

For engineers reviewing the PI3B3257AQE datasheet, PI3B3257AQE pinout, PI3B3257AQE application, or PI3B3257AQE equivalent, key selection criteria include guaranteed 3.3 V operation, rail-to-rail logic input tolerance up to +3.6 V, QSOP-16 package compatibility, and ultra-low power consumption for battery-sensitive designs.

Technical Context

The device implements four independent bidirectional analog/digital switches controlled by a shared select (S) and enable (E) input. Each switch exhibits near-zero propagation delay due to its passive FET architecture-delay arises only from RC time constant of 5 Ω R_ON and load capacitance-not active logic stages.

Logic inputs tolerate voltages up to +3.6 V regardless of V_CC, supporting mixed-voltage interfacing. The 16-pin QSOP package supports surface-mount assembly with 150 mil width and Pb-free/Green compliance per RoHS 3.

Key Specifications

Pinout & Package

Package: 16-pin QSOP (150 mil wide), Pb-free and RoHS 3 compliant, marked "PI3B3257AQE" with date/assembly/fab codes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PI3B3257AQE, PI3B3257 offers identical performance with reduced traceability, while PI3CH480 extends voltage flexibility and lowers R_ON at the cost of package size and pin count-making the AQE variant optimal for space-constrained 3.3 V notebook designs requiring full lot traceability.

Availability

PI3B3257AQE is available at Aetrix Electronics and suitable for notebook computing, industrial I/O modules, and USB docking station designs requiring stable component supply and full production traceability.

Supply support for PI3B3257AQE 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-performance, energy-efficient solutions for computing, industrial, and consumer markets.

The PI3B3257A belongs to Diodes' NanoSwitch™ product line, engineered for ultra-low-power, high-speed signal routing in portable and space-constrained embedded systems.

FAQ

Is PI3B3257AQE pin-compatible with standard 74-series 257 logic devices?

Yes, PI3B3257AQE is functionally and pinout-compatible with 74F257, 74ALS257, and 74AS257. Its 16-pin QSOP footprint matches industry-standard 257 layouts, allowing direct replacement without PCB modification. All control (S, E) and I/O pin assignments align exactly with those legacy parts, including shared enable and select logic.

What is the maximum input voltage tolerance for logic control pins?

The S and E control inputs tolerate –0.5 V to +4.6 V DC, independent of V_CC. When powered from 3.3 V, they accept TTL-level (0–3.6 V) or 5 V-tolerant logic signals without clamping diodes or level shifters. This enables seamless interfacing with mixed-voltage microcontrollers and FPGAs in heterogeneous system designs.

Does PI3B3257AQE support hot-swap or live-insertion operation?

No-hot-swap is not supported. Per datasheet guidelines, V_CC and GND must be applied before any signal appears on I/O or control pins. Applying inputs prior to power risks latch-up or damage due to internal ESD structures. Proper power sequencing is mandatory; use external power-good monitoring or sequencer ICs in systems requiring hot-plug capability.

How does the 5 Ω on-resistance impact analog signal fidelity?

At 5 Ω R_ON, voltage drop across the switch is ≤5 mV at 1 mA signal current, introducing negligible gain error (<0.1%) in sensor or audio paths. Combined with <4 pF off-capacitance, it preserves bandwidth beyond 100 MHz and minimizes crosstalk-verified in USB 2.0 and LVDS applications where signal integrity is critical.