Diodes Incorporated PI2PCIE2422ZHEX

Overview

PI2PCIE2422ZHEX from Pericom Semiconductor is an 8-channel differential SPST switch with configurable 8:4 mux/demux functionality, designed for PCI Express Gen II (5.0 Gbps) signal routing. It supports dual-lane PCIe switching with 10 ps bit-to-bit skew, –15 dB crosstalk at 3.0 GHz, and operates from 1.4 V to 1.8 V ±10%. Used in server backplanes and PCIe switch fabric expansion.

For engineers reviewing the PI2PCIE2422ZHEX datasheet, PI2PCIE2422ZHEX pinout, PI2PCIE2422ZHEX application, or PI2PCIE2422ZHEX equivalent, key selection criteria include differential insertion loss (–3 dB at 3 GHz), off-isolation (–26 dB @ 3.0 GHz), SEL-controlled signal path routing, and TQFN-42 package compatibility with high-density PCB layouts.

Technical Context

The PI2PCIE2422ZHEX implements a dual-mode differential switch matrix: when SEL = LOW, A↔B and C↔D paths are active (8-channel pass-through); when SEL = HIGH, A↔D is enabled while B and C enter high-impedance state. All I/O pins support AC-coupled PCIe differential signaling with 100 Ω differential impedance.

It uses CMOS-based analog switch architecture with rail-to-rail input voltage tolerance (–0.5 V to VDD), 10 Ω typical on-resistance, and 2.0 pF channel capacitance - optimized for minimal eye diagram degradation in 5 Gbps serial links. ESD robustness exceeds 2 kV HBM across all pins.

Key Specifications

Pinout & Package

Package: 42-contact Thin Quad Flat No-Lead (TQFN), Pb-free and RoHS-compliant, with exposed thermal pad (ZH42 footprint per JEDEC MO-220).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PCIe Gen II differential switching applications.

Compared with PI3CH401ZHEX and TS3L110PWR, the PI2PCIE2422ZHEX uniquely delivers PCIe Gen II–validated differential performance, integrated 8:4 mux/demux logic, and 1.5 V operation - making it the sole option for production-grade, standards-compliant PCIe lane management in space-constrained systems.

Availability

PI2PCIE2422ZHEX is available at Aetrix Electronics and suitable for PCIe Gen II server backplanes, embedded computing expansion modules, and test equipment signal path control requiring stable component supply and long-term lifecycle support.

Supply support for PI2PCIE2422ZHEX 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 (acquired by Diodes Incorporated in 2016) specialized in high-speed interface ICs including PCIe, USB, HDMI, and Ethernet signal conditioning solutions.

The PI2PCIE2422 belongs to Pericom's PCIe Gen II switch portfolio, engineered specifically for low-skew, low-loss differential signal routing in enterprise and embedded computing platforms where protocol transparency and electrical compliance are mandatory.

FAQ

Does PI2PCIE2422ZHEX support PCIe Gen III or higher data rates?

No. The device is characterized and validated only for PCIe Gen II (5.0 Gbps). Its –3 dB bandwidth of 2.5 GHz and insertion loss profile do not meet Gen III (8.0 Gbps) eye opening or jitter requirements. Use of this part in Gen III systems may result in link training failure or excessive bit error rates.

Can SEL be driven directly from a 3.3 V GPIO without level shifting?

No. VIH is specified as 0.65 × VDD, meaning at VDD = 1.5 V, VIH = 0.975 V max. A 3.3 V GPIO exceeds absolute maximum input voltage (–0.5 V to VDD), risking latch-up or permanent damage. A level shifter or resistor divider is required to limit SEL voltage to ≤1.8 V.

Is the exposed thermal pad electrically connected to GND internally?

No. The exposed pad is a mechanical thermal slug only - it is not bonded to any internal die node. Pericom's ZH42 package drawing specifies it must be soldered to a PCB thermal plane for heat dissipation but left floating electrically unless explicitly tied to GND via layout design.

What is the recommended termination for differential I/O pins?

Each differential pair must be terminated with 100 Ω across the pair (not to ground), matching the characteristic impedance of standard PCIe PCB traces. AC coupling capacitors (typically 100 nF) are required on all I/O lines per PCIe CEM specification to block DC offset and ensure common-mode voltage compatibility.