Diodes Incorporated PI3EQX16621ZLDEX

Overview

PI3EQX16621ZLDEX from Diodes Incorporated is a 16Gbps, 4-channel PCIe Mux ReDriver IC designed for signal integrity restoration in high-speed serial links. It implements 2:1 multiplexing per channel, supports full PCIe Gen1–Gen4 compliance, features pin-controlled linear equalization/swing/flat gain, and operates with 100Ω differential CML I/Os at 3.3V supply across 0°C to 70°C.

For engineers reviewing the PI3EQX16621ZLDEX datasheet, PI3EQX16621ZLDEX pinout, PI3EQX16621ZLDEX application, or PI3EQX16621ZLDEX equivalent, key selection criteria include its 16Gbps per-lane bandwidth, independent channel operation with RXDET-based squelch, adaptive power management for low-power platforms, and TQFN-40 (ZLD) package compatibility with dense motherboard layouts.

Technical Context

The PI3EQX16621ZLDEX is a linear ReDriver-not a retimer-preserving PCIe link training transparency while compensating for channel loss via programmable analog equalization. Each of its four independent channels supports two 100Ω CML inputs (A/RX and B/RX) and one output (TX), enabling 2:1 mux functionality without protocol layer intervention.

Its equalization circuitry operates before the input receiver, allowing pre-compensation of degraded signals from long traces or cables. Input-level detection triggers automatic output squelch and enables adaptive power-down per channel, reducing dynamic power in idle lanes without external control logic.

Key Specifications

Pinout & Package

ZLD-40 (TQFN, 3mm × 6mm, 0.4mm pitch) - thermally enhanced, lead-free, halogen-free package with exposed thermal pad; footprint optimized for PCIe routing density and signal integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PCIe ReDriver applications.

Compared with TI TUSB1042IRNQT and MAX9286GTJ+, the PI3EQX16621ZLDEX delivers lower-latency, protocol-transparent signal restoration at 16Gbps with hardware-configurable EQ-making it optimal for PCIe-native motherboard and workstation designs where link training integrity and deterministic timing are mandatory.

Availability

PI3EQX16621ZLDEX is available at Aetrix Electronics and suitable for high-end motherboard expansion, workstation PCIe switch fabric, server backplane signal extension, and embedded AI accelerator carrier board applications requiring stable component supply and RoHS 3-compliant sourcing.

Supply support for PI3EQX16621ZLDEX 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, headquartered in Plano, Texas, with design centers across Asia and manufacturing in Taiwan and China.

The PI3EQX16621ZLDEX belongs to Diodes' high-speed interface ReDriver product line, engineered specifically for PCIe Gen4 signal integrity restoration in space-constrained, thermally demanding computing platforms.

FAQ

What is the difference between a ReDriver and a retimer in PCIe applications?

A ReDriver like the PI3EQX16621ZLDEX is an analog signal conditioner that amplifies and equalizes high-speed serial data without altering timing or protocol content. It preserves PCIe link training transparency and adds no latency, unlike a retimer which recovers clock and data, retransmits with new timing, and introduces ~10–20ns delay. This makes the PI3EQX16621ZLDEX ideal for latency-sensitive motherboard interconnects.

Does PI3EQX16621ZLDEX require I²C or firmware configuration?

No. The PI3EQX16621ZLDEX uses dedicated pins (EQ1/EQ2/EQ3, SFA/SFB, SEL) for static configuration of equalization, output swing, and mux selection. No microcontroller, I²C bus, or firmware initialization is needed-enabling immediate operation after power-up and simplifying system validation.

Can PI3EQX16621ZLDEX be used with PCIe Gen5?

The PI3EQX16621ZLDEX is specified up to 16Gbps (PCIe Gen4). While some Gen5 (32Gbps) channels may pass with marginal margin under ideal conditions, Diodes does not guarantee Gen5 compliance. For Gen5 designs, Diodes recommends the PI3EQX16912ZLDEX-a pin-compatible 32Gbps variant with updated EQ architecture.

How does the PRSNT# pin affect RXDET functionality?

The PRSNT# pin must be pulled low to enable the internal RXDET circuitry that monitors input signal amplitude and triggers output squelch. When PRSNT# is high (or left floating), RXDET is disabled and all outputs remain active regardless of input presence-useful for debug or forced-enable scenarios but increases static power consumption.