Diodes Incorporated PI2USB4122ZHEX

Overview

PI2USB4122ZHEX from Diodes Incorporated is a 4:1 differential USB 3.0 multiplexer/demultiplexer switch supporting 5.0 Gbps data rates, featuring 7 ps max bit-to-bit skew, –23 dB crosstalk at 3 GHz, and operation from 1.8 V ±10%. It routes high-speed differential USB 3.0 SuperSpeed signals between one common port (Z) and four selectable channel pairs (A–D) in host-peripheral switching applications.

For engineers reviewing the PI2USB4122ZHEX datasheet, PI2USB4122ZHEX pinout, PI2USB4122ZHEX application, or PI2USB4122ZHEX equivalent, key selection criteria include differential insertion loss (–3.0 dB at 2.5 GHz), off-isolation (–25 dB), channel-to-channel skew (35 ps), ESD tolerance (2 kV HBM), and TQFN-42 package compatibility with high-density USB 3.0 routing layouts.

Technical Context

The PI2USB4122ZHEX implements a single-pole, four-throw (SP4T) differential analog switch architecture with dual control inputs (SEL0/SEL1) enabling discrete selection of one of four 100 Ω differential channel pairs. Its internal low-R_ON FET design maintains signal integrity across the full 2.6 GHz bandwidth.

It operates exclusively from a 1.8 V ±10% supply, draws only 200–300 µA quiescent current, and supports logic-level compatible control with VIH ≥ 0.65×VDD and VIL ≤ 0.35×VDD - ensuring reliable interfacing with standard 1.8 V GPIOs in host controllers and hub ICs.

Key Specifications

Pinout & Package

The PI2USB4122ZHEX is housed in a 42-contact, 5 mm × 5 mm, 0.5 mm pitch Very Thin Quad Flat No-Lead (TQFN-ZH) package with exposed thermal pad. Pin numbering follows standard TQFN convention, with power/ground distributed across multiple pins for low-impedance return paths and reduced ground bounce.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB 3.0 4:1 mux/demux applications.

Compared with TS3USB30E and PI3USB3022, the PI2USB4122ZHEX uniquely delivers native 4:1 differential USB 3.0 switching in a single 1.8 V device - reducing component count, eliminating inter-device skew, and simplifying GPIO control for full dual-lane SuperSpeed routing.

Availability

PI2USB4122ZHEX is available at Aetrix Electronics and suitable for USB 3.0 host switching, multi-port docking stations, and embedded system expansion requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for PI2USB4122ZHEX 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, specializing in high-performance analog, logic, and protection solutions for computing, consumer, and industrial markets.

The PI2USB4122 belongs to Diodes' high-speed interface switch product line, engineered specifically for USB 3.0, PCIe, and DisplayPort signal routing with minimal insertion loss and ultra-low skew.

FAQ

What is the maximum recommended PCB trace length between PI2USB4122ZHEX and a USB 3.0 connector?

For optimal 5.0 Gbps signal integrity, differential trace lengths from the PI2USB4122ZHEX Z0+/Z0− and Z1+/Z1− outputs to the USB 3.0 connector should not exceed 30 mm with controlled 100 Ω impedance and tight pair matching. Longer traces require simulation-validated layout rules including via minimization and ground plane continuity.

Does PI2USB4122ZHEX support hot-plug detection or USB protocol handshaking?

No. The PI2USB4122ZHEX is a passive analog switch and does not interpret or participate in USB protocol layers. Hot-plug detection and link training remain handled entirely by the upstream USB 3.0 host controller and downstream device PHYs - the switch only passes differential signals transparently.

Can SEL0/SEL1 be driven directly from a 3.3 V microcontroller GPIO?

No. SEL0/SEL1 require logic-high input voltage ≥0.65×VDD (≥1.17 V) and logic-low ≤0.35×VDD (≤0.63 V). Driving them from 3.3 V GPIO without level shifting violates absolute maximum ratings and risks latch-up. A 1.8 V-compatible GPIO or dedicated level shifter is mandatory.

Is the exposed thermal pad on the TQFN-ZH package required to be soldered to PCB ground?

Yes. The exposed pad must be soldered to a solid thermal pad connected to at least six GND vias (0.3 mm diameter) to the internal ground plane. This ensures adequate heat dissipation and maintains specified electrical performance - especially for crosstalk and isolation - per Diodes' mechanical drawing 17-0266.