Diodes Incorporated PI2EQX5964ZFEX

Overview

PI2EQX5964ZFEX from Diodes Incorporated is a PCIe® 2.0-compliant 4-lane, 5.0 Gbps serial ReDriver with programmable equalization, de-emphasis, and I²C control. It conditions high-speed differential signals across backplanes, cables, or long PCB traces in blade server interconnects, supports eight 100-Ω CML I/Os, operates from a single 1.2 V ±0.05 V supply, and functions across –40°C to +85°C.

For engineers reviewing the PI2EQX5964ZFEX datasheet, PI2EQX5964ZFEX pinout, PI2EQX5964ZFEX application, or PI2EQX5964ZFEX equivalent, key selection criteria include lane count (4), data rate (5.0 Gbps), I²C configurability, electrical idle support, and TQFN-56 package compatibility with PCIe 2.0 signal integrity requirements.

Technical Context

The PI2EQX5964ZFEX implements per-lane adaptive equalization on receiver inputs and programmable de-emphasis on transmitter outputs to compensate for frequency-dependent loss in PCIe 2.0 channels. Its 8-bit I²C interface enables real-time tuning of gain, output swing, and electrical idle threshold without requiring hardware changes.

It supports channel-level loopback, 1:2 broadcast, and mux/demux modes via dedicated control pins (LB#, RES_x, SELy_x), and integrates input level detection logic to autonomously manage receiver detect and individual output enable/disable per lane.

Key Specifications

Pinout & Package

Package: 56-contact, 7 mm × 7 mm, 0.4 mm pitch, exposed pad TQFN (Pb-free & Green).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PCIe 2.0 redriving applications.

Compared with TI TUSB1002A and MAX9278, the PI2EQX5964ZFEX uniquely delivers PCIe 2.0–specific equalization, electrical idle compliance, and I²C-configurable per-lane de-emphasis - making it the only validated solution for industrial blade server and storage expansion where protocol-aware signal restoration is mandatory.

Availability

PI2EQX5964ZFEX is available at Aetrix Electronics and suitable for blade server backplanes, PCIe cable extenders, and industrial switch fabrics requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for PI2EQX5964ZFEX 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 PI2EQX5964ZFEX belongs to Diodes' high-speed interface product line, engineered specifically for PCIe 2.0 signal integrity restoration in space-constrained, thermally demanding compute and storage platforms.

FAQ

What is the maximum supported trace length for PI2EQX5964ZFEX in a typical FR4 PCB?

The PI2EQX5964ZFEX compensates up to 20 dB of channel loss at 2.5 GHz. In standard 6-layer FR4 with 100 Ω differential impedance, this corresponds to approximately 20–24 inches of trace length before and after the device, depending on dielectric constant and conductor roughness. Actual reach must be verified with channel simulation using the device's S-parameter model.

Does PI2EQX5964ZFEX support PCIe 2.0 Link Training and Status State Machine (LTSSM)?

No. The PI2EQX5964ZFEX is a transparent analog redriver and does not participate in LTSSM. It passes all training sequences, TS1/TS2 ordered sets, and electrical idle transitions unmodified while restoring signal amplitude and edge integrity. Link training remains fully handled by the root complex and endpoint devices.

Can PI2EQX5964ZFEX operate with 3.3 V I²C controllers without level shifters?

Yes. The SDA and SCL pins are explicitly rated 3.3 V tolerant per the official Diodes datasheet. They accept 3.3 V logic levels while operating from a 1.2 V core supply, eliminating the need for external level-shifting circuitry in mixed-voltage system management buses.

Is thermal pad soldering required for PI2EQX5964ZFEX reliability?

Yes. The exposed thermal pad on the underside of the 56-pin TQFN package must be soldered to a solid copper thermal plane on the PCB. Diodes specifies ≥80% solder coverage for optimal junction-to-board thermal resistance (θ_JB = 22°C/W), ensuring safe operation at full lane loading within the –40°C to +85°C ambient range.