Diodes Incorporated PI3B32X384BEX

Overview

PI3B32X384BEX from Pericom Semiconductor is a 3.3V, 20-bit dual-port bus switch with four independent bus enable inputs (BEA, BEB, BEC, BED), 5Ω typical ON-resistance, 4.5ns max switching speed, and near-zero propagation delay. It enables direct A-to-B or B-to-A signal routing in high-speed memory/data buses for notebook and embedded computing systems.

For engineers reviewing the PI3B32X384BEX datasheet, PI3B32X384BEX pinout, PI3B32X384BEX application, or PI3B32X384BEX equivalent, key selection criteria include its 20-bit bidirectional switching architecture, TTL-compatible control logic, ultra-low quiescent current (0.1µA typ), and 48-pin BQSOP package compatibility with space-constrained PCB layouts.

Technical Context

The PI3B32X384BEX implements two independent 10-bit bidirectional switch banks-upper (A19–A15/B19–B15 and A9–A5/B14–B10) and lower (A4–A0/B4–B0)-each controlled by dedicated active-low bus enable signals. Its CMOS transmission-gate topology ensures rail-to-rail analog/digital signal pass-through without level shifting.

Each switch exhibits 5Ω typical ON-resistance at V_CC = 3.3V and 15mA, with input/output capacitance of 3.0pF (C_IN), 16.0pF (C_ON), and 8.0pF (C_OFF). Propagation delay is dominated solely by RC time constant (RON × C_L), adding ≤0.25ns to system timing with 50pF load.

Key Specifications

Pinout & Package

PI3B32X384BEX is housed in a 48-pin, 150-mil wide plastic BQSOP (B) package with Pb-free & Green (RoHS-compliant) construction. Pin pitch is 0.025 inch (0.635 mm); body width is 3.80–4.00 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 20-bit bus switch applications.

Compared with PI3B32X384BEX, PI3B32424BEX offers reduced channel density but lower gate count, while SN74CBT3244DBR provides tighter R_ON at the cost of 5V-only operation and halved bit width-neither matches the 20-bit, 3.3V, quad-enable flexibility of the original.

Availability

PI3B32X384BEX is available at Aetrix Electronics and suitable for memory expansion interfaces, low-power notebook bus isolation, PCIe sideband routing, and embedded controller interconnects requiring stable component supply and long-term industrial availability.

Supply support for PI3B32X384BEX 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 ICs, including clock buffers, USB switches, and bus switches, with focus on signal integrity and low-power design.

The PI3B32X384 belongs to Pericom's NanoSwitch™ family-designed specifically for zero-delay, low-R_ON bidirectional signal routing in portable and space-constrained computing platforms.

FAQ

What is the maximum capacitive load the PI3B32X384BEX can drive while maintaining 4.5ns switching?

The 4.5ns max switching time is specified at CL = 50pF and RL = 500Ω. With its 5Ω R_ON, the device maintains sub-5ns performance up to ~60pF total load (including board trace and receiver capacitance). Beyond that, RC delay increases linearly-e.g., 100pF yields ~0.5ns additional delay.

Can BEA–BED be tied together for simplified control?

Yes-BEA, BEB, BEC, and BED may be paralleled to operate all 20 bits simultaneously. However, doing so eliminates independent segment control and increases enable-node capacitance, potentially slowing BE transition by ~20% versus individual routing.

Does PI3B32X384BEX support hot insertion with V_CC unpowered?

No. Absolute maximum ratings require V_CC and GND to be applied before any signal or control input. Applying A/B or BE signals with V_CC = 0V risks latch-up or ESD damage due to internal clamp diode conduction.

How does the 0.1µA quiescent current behave across temperature?

Quiescent current remains ≤0.5µA over the full –40°C to +85°C range. At –40°C, it drops to ~0.05µA; at +85°C, it rises to ~0.3µA-still negligible for battery-life calculations in always-on subsystems.