Diodes Incorporated PI3B3244QE

Overview

PI3B3244QE from Diodes Incorporated is a 3.3V, 8-bit dual-port bus switch IC with two independent enable-controlled bidirectional data paths (1A↔1B and 2A↔2B), 5 Ω on-resistance, 4.5 ns max switching time, and ultra-low quiescent current (0.2 μA typical), used for hot-insertion-capable signal routing in notebook and embedded system backplanes.

For engineers reviewing the PI3B3244QE datasheet, PI3B3244QE pinout, PI3B3244QE application, or PI3B3244QE equivalent, key selection criteria include dual-enable logic compatibility with 74F244/74ALS244, rail-to-rail input tolerance up to +3.6V, near-zero propagation delay contribution, and QSOP-20 packaging for space-constrained PCB layouts.

Technical Context

The PI3B3244QE implements two independent 4-bit bidirectional bus switches per port, each controlled by separate active-low enable inputs (BE1, BE2), allowing selective connection of A-side and B-side buses without direction control pins or voltage translation. Its sub-micron CMOS process enables rail-to-rail input operation and eliminates ground bounce during switching.

Switching behavior follows a truth table where both enables low connect all eight A/B pairs (1A–1B, 2A–2B), while individual enables isolate respective ports. The device contributes only RC delay (≈0.25 ns for 50 pF load) - no intrinsic propagation delay - making timing predictable in high-speed digital interconnects.

Key Specifications

Pinout & Package

PI3B3244QE is packaged in a Pb-free, green 20-pin QSOP (150-mil width), with 0.65 mm pitch and standard JEDEC MO-137AC footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit dual-port bus switch applications.

Compared with PI3CH3244QE, the PI3B3244QE lacks certified ESD hardening but offers identical timing and lower cost for non-certified applications; versus SN74CBT3244PWR, it delivers superior rail-to-rail input flexibility and 30% lower quiescent current at 3.3 V, critical for portable power budgets.

Availability

PI3B3244QE is available at Aetrix Electronics and suitable for notebook memory expansion slots, embedded backplane interconnects, PCIe sideband routing, and legacy peripheral multiplexing requiring stable component supply and long-term obsolescence management.

Supply support for PI3B3244QE 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 components for computing, consumer, industrial, and communications markets.

The PI3B3244QE belongs to Diodes' Pericom-branded NanoSwitch™ logic portfolio, designed specifically for low-latency, low-power, hot-pluggable signal routing in mobile and modular electronic systems.

FAQ

What is the maximum operating temperature range for PI3B3244QE?

The PI3B3244QE is specified for ambient operation from –40°C to +85°C with VCC = 3.3 V ±10%. It meets this range under continuous DC loading and switching conditions, and its thermal resistance (θJA) is optimized for QSOP-20 mounting on standard FR-4 PCBs with 2 oz copper and 2 internal planes.

Can PI3B3244QE be used with 5 V logic inputs?

No - PI3B3244QE inputs tolerate up to +3.6 V regardless of VCC, making them incompatible with standard 5 V TTL or CMOS logic levels. Applying >3.6 V risks latch-up or permanent damage. For 5 V systems, consider SN74CBT3244PWR or PI3CH3244QE with verified 5 V tolerant variants.

Is PI3B3244QE pin-compatible with 74F244 devices?

Yes - PI3B3244QE is functionally and pinout-compatible with 74F244, 74ALS244, and P74FCT244T, sharing identical 20-pin QSOP/TSSOP pin assignments for BE, A/B buses, VCC, and GND. However, unlike those drivers, it provides bidirectional switching without direction pins or output enable inversion.

Does PI3B3244QE require external pull-up or pull-down resistors on BE pins?

No - BE1 and BE2 have CMOS-compatible input structure with ±1 μA leakage; they may be driven directly from FPGA GPIO or microcontroller outputs. Pull resistors are unnecessary unless floating-state prevention is required during power-up sequencing, in which case 10 kΩ to VCC is recommended.