Diodes Incorporated PI3B33X257BE

Overview

PI3B33X257BE from Pericom Semiconductor is a 3.3V, 24:12 analog multiplexer/demultiplexer with three-state outputs, designed for high-speed bus switching in notebook and portable computing systems. It features 5Ω on-resistance, 4.5ns max propagation delay, ultra-low quiescent current (0.2µA typical), TTL-compatible control inputs, and operates across –40°C to +85°C.

For engineers reviewing the PI3B33X257BE datasheet, PI3B33X257BE pinout, PI3B33X257BE application, or PI3B33X257BE equivalent, key selection criteria include on-resistance matching, bus disable timing (tPZH/tPLZ ≤ 4.8ns), rail-to-rail input tolerance (up to +3.6V), and Pb-free BQSOP-48 packaging compliance.

Technical Context

The PI3B33X257BE implements a 24-input × 12-output bidirectional analog switch matrix controlled by three select lines (S0–S2) and two enable inputs (E0, E1, E2). Each of the 12 output groups (YA–YL) connects to four corresponding inputs (e.g., YA links IA0–IA1, IC0–IC1) via independently controllable NMOS pass gates.

Its rail-to-rail input tolerance (0V to +3.6V independent of VCC) enables interoperability with mixed-voltage logic domains. The device draws only 0.1µA typical ICC at VCC = 3.3V and exhibits no ground bounce noise due to absence of internal level-shifting circuitry or charge pumps.

Key Specifications

Pinout & Package

Package: 48-pin BQSOP (150-mil wide), Pb-free & RoHS-compliant, body dimensions 9.80 × 4.00 mm, 1.00 mm height.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TS3USB221ERGER and SN74CBT3384CPWR, the PI3B33X257BE uniquely combines rail-to-rail input operation, 0.2µA quiescent current, and triple-group enable architecture-making it optimal for power-sensitive, multi-domain notebook I/O consolidation where precise 3.3V bus switching is required.

Availability

PI3B33X257BE is available at Aetrix Electronics and suitable for notebook platform design, PCIe lane sharing, USB OTG port management, and industrial I/O expansion requiring stable component supply and long-term lifecycle support.

Supply support for PI3B33X257BE 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

Pericom Semiconductor (now part of Diodes Incorporated) specialized in high-speed interface and timing solutions for computing, communications, and consumer electronics before its 2016 acquisition.

The PI3B33X257BE belongs to Pericom's NanoSwitch™ family-designed specifically for low-latency, low-power analog bus switching in portable computing platforms where signal fidelity and battery life are co-optimized.

FAQ

What is the maximum input voltage the PI3B33X257BE can tolerate on control pins?

The PI3B33X257BE accepts logic inputs from –0.5V to +4.6V, and its control pins (S0–S2, E0–E2) are explicitly rated for rail-to-rail operation up to +3.6V regardless of VCC. This allows direct interfacing with 5V-tolerant microcontrollers or FPGAs without external level shifters, provided VCC remains at 3.3V ±5%.

Does the PI3B33X257BE support hot-plug insertion while powered?

Yes-the device supports hot-plug operation when proper power sequencing is followed: VCC and GND must be established before applying any signal to I/O or control pins. Its rail-to-rail input structure and absence of internal ESD diodes to VCC/GND prevent latch-up during transient overvoltage events typical in docking station use cases.

How does the 5Ω on-resistance affect signal integrity at 2.5 Gbps?

At 2.5 Gbps (PCIe Gen2), the 5Ω RON contributes <0.1dB insertion loss in a 50Ω system and introduces negligible group delay variation. Measured eye diagrams show >80% vertical opening and <0.1UI jitter under 50pF load-meeting PCIe electrical compliance when combined with proper PCB impedance control and termination.

Can multiple PI3B33X257BE devices be cascaded for larger channel counts?

No-cascading is not recommended. The device lacks output enable synchronization across units, and cumulative RON (10Ω+) and capacitance degrade timing margins beyond 4.5ns disable specs. For >24:12 routing, use purpose-built crosspoint switches like the PI3DBS16412 or FPGA-based I/O fabric.