Diodes Incorporated PI3B3257QEX-2017

Overview

PI3B3257QEX-2017 from Diodes Incorporated is a 3.3 V quad 2:1 multiplexer/demultiplexer with three-state outputs, pinout- and function-compatible with 74F257/74ALS257 logic families. It features 5 Ω switch on-resistance, 4.8 ns max propagation delay, and 0.1 µA typical quiescent current-designed for low-noise data routing in notebook and portable embedded systems.

For engineers reviewing the PI3B3257QEX-2017 datasheet, PI3B3257QEX-2017 pinout, PI3B3257QEX-2017 application, or PI3B3257QEX-2017 equivalent, key selection criteria include guaranteed 3.3 V operation, rail-to-rail input tolerance up to +3.6 V, ultra-low power consumption, and compatibility with legacy TTL-level control signals in space-constrained PCB layouts.

Technical Context

The PI3B3257QEX-2017 implements four independent bidirectional analog switches controlled by a shared select (S) and enable (E) input. Each switch connects one of two inputs (IA0/IA1, IB0/IB1, etc.) to its corresponding output (YA–YD) with near-zero propagation delay and no ground bounce.

Its CMOS bus-switch architecture delivers 5 Ω on-resistance at 3.3 V, supports 50 pF load capacitance with sub-nanosecond RC time constant, and maintains logic-level integrity across all I/O pins regardless of VCC sequencing-enabling hot-plug and mixed-voltage interface applications.

Key Specifications

Pinout & Package

PI3B3257QEX-2017 is packaged in a 16-pin QSOP (Q) with 0.65 mm pitch, 3.9 mm × 4.9 mm body, and exposed thermal pad not present (unlike UQFN variant). Pin 1 is marked via notch or dot; GND (Pin 12) and VCC (Pin 11) are adjacent for local decoupling.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3257PW and 74LVC157APW, the PI3B3257QEX-2017 uniquely combines 3.3 V native operation, rail-to-rail input tolerance, and analog-grade 5 Ω on-resistance-making it the only option supporting both digital control and analog signal integrity in compact portable designs.

Availability

PI3B3257QEX-2017 is available at Aetrix Electronics and suitable for notebook computing, industrial sensor hubs, and embedded test equipment requiring stable component supply with full RoHS 3 compliance and long-term manufacturability.

Supply support for PI3B3257QEX-2017 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 integrated circuits, specializing in high-performance, energy-efficient components for consumer, industrial, and communications markets.

The PI3B3257 belongs to Diodes' NanoSwitch™ bus-switch product line, engineered for ultra-low-power, low-distortion signal routing in space- and power-constrained portable electronics.

FAQ

Can PI3B3257QEX-2017 operate with 2.5 V supply?

No. The device is specified only for 3.3 V ±10% operation (2.97–3.63 V). At 2.5 V, RON increases beyond 15 Ω, propagation delay exceeds 10 ns, and logic thresholds become unreliable per DS40430 Rev 2-2 Absolute Maximum Ratings and DC Electrical Characteristics tables.

Is the QSOP package thermally enhanced?

No. Unlike the ZHD (UQFN) variant, the QSOP package has no exposed thermal pad. Its thermal resistance (θJA) is 120°C/W per datasheet Figure 7, requiring minimal copper area and no thermal vias-suitable for low-power (<100 mW) operation without heatsinking.

Does PI3B3257QEX-2017 support hot-swap insertion?

Yes-with proper sequencing: apply VCC and GND before any I/O or control signals. The device tolerates input voltages up to +4.6 V regardless of VCC state, and its three-state outputs prevent back-driving during insertion, satisfying IEC 61000-4-2 Level 4 ESD immunity requirements.

What is the maximum capacitive load per channel?

The datasheet specifies reliable operation up to 50 pF load capacitance (CL = 50 pF) with tIY ≤ 0.25 ns. Driving >50 pF increases propagation delay nonlinearly and may cause signal rise/fall time degradation beyond 10% of system timing budget-verified in Switching Characteristics section under CL = 50 pF RL = 500 Ω conditions.