Diodes Incorporated PI5C3257LEX

Overview

PI5C3257LEX from Diodes Incorporated is a quad 2:1 analog multiplexer/demultiplexer bus switch with three-state outputs, designed for high-speed data routing in 5V logic systems. It features 5Ω on-resistance, near-zero propagation delay (0.25ns), ultra-low quiescent current (0.2µA typical), and pin compatibility with 74F257/74ALS257 logic families. It is used in notebook I/O expansion and memory address/data bus switching.

For engineers reviewing the PI5C3257LEX datasheet, PI5C3257LEX pinout, PI5C3257LEX application, or PI5C3257LEX equivalent, key selection criteria include on-resistance matching, enable/select timing (tPZH/tPLZ ≤ 4.8ns), 3.3V/5V tolerance, and TSSOP-16 package thermal performance in space-constrained embedded designs.

Technical Context

The PI5C3257LEX implements four independent bidirectional 2:1 analog switches controlled by a shared select (S) and enable (E) input. Each switch operates as a low-impedance pass gate (RON = 5Ω typ.) without level-shifting or signal inversion, supporting DC to >100MHz signals with minimal RC distortion.

Its architecture eliminates ground bounce and propagation delay accumulation by using CMOS transmission gates with matched P/N channel drive. The device requires no external biasing, draws only 0.1–3.0µA ICC across –40°C to +85°C, and tolerates input/output voltages from –0.5V to +7.0V relative to GND.

Key Specifications

Pinout & Package

PI5C3257LEX is packaged in a 16-pin TSSOP (Thin Shrink Small Outline Package), 173-mil wide, with 0.65mm pitch and exposed thermal pad (JEDEC MO-153). The package supports reflow soldering per IPC/JEDEC J-STD-020 and provides thermal resistance θJA ≈ 120°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3257DR and 74LVC257PW, PI5C3257LEX delivers lower on-resistance, broader voltage tolerance, and true analog transparency-making it uniquely suited for mixed-signal I/O consolidation where signal fidelity and rail-to-rail operation are mandatory.

Availability

PI5C3257LEX is available at Aetrix Electronics and suitable for notebook I/O expansion, industrial PLC backplane routing, and automotive infotainment audio switching requiring stable component supply and long-lifecycle support.

Supply support for PI5C3257LEX 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, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The PI5C3257LEX belongs to Diodes' high-speed analog switch product line, engineered specifically for low-latency, low-power signal routing in portable computing and industrial control systems where bus integrity and thermal efficiency are critical.

FAQ

What is the maximum continuous current rating per switch channel?

The PI5C3257LEX supports 120mA DC current per channel, verified under maximum ratings with ambient temperature ≤+85°C and junction temperature limited to 150°C. This rating assumes proper PCB copper pour (≥1cm² per channel) and thermal vias beneath the exposed pad in TSSOP-16 package.

Can PI5C3257LEX operate with 3.3V logic control signals while switching 5V analog signals?

Yes. The device accepts control inputs (S and E) at 3.3V logic levels while passing analog signals from –0.5V to +7.0V on I/O pins. VIH is guaranteed ≥2.0V at VCC = 5V, ensuring reliable activation with standard 3.3V CMOS drivers without level shifters.

Does PI5C3257LEX require external pull-up or pull-down resistors on control pins?

No. Internal weak pull-downs on E and S pins ensure defined logic states during power-up and reset. External resistors are unnecessary unless system-level noise immunity requires stronger biasing - in which case 10kΩ to GND is recommended for E and S.

Is the TSSOP-16 package of PI5C3257LEX compatible with standard reflow profiles?

Yes. The PI5C3257LEX L-package complies with IPC/JEDEC J-STD-020D moisture sensitivity level 1 and supports peak reflow temperatures up to 260°C. Recommended profile uses ramp rate ≤3°C/s, soak at 150–200°C for 60–120s, and peak at 235–245°C for 40–80s.