NXP Semiconductors PX1011A-EL1/G,551

Overview

PX1011A-EL1/G from NXP Semiconductors (formerly Philips Semiconductors) is a single-lane, 2.5 Gbit/s PCI Express 1.1-compliant stand-alone physical layer (PHY) IC. It implements full SerDes functionality with 8b/10b encoding/decoding, clock and data recovery (CDR), elastic buffer, receiver detection, and loopback-designed for off-chip interconnect between FPGA-based MACs and PCIe links. Used in embedded computing, industrial control backplanes, and legacy PCIe endpoint interfaces requiring low-power, pin-defined PHY bridging.

For engineers reviewing the PX1011A-EL1/G datasheet, PX1011A-EL1/G pinout, PX1011A-EL1/G application, or PX1011A-EL1/G equivalent, this page delivers verified electrical specifications, LFBGA81 package mapping, SSTL_2 timing alignment details, power state behavior (L0/L0s/L1), and real-world PHY/MAC interface constraints-not generic PCIe PHY descriptions.

Technical Context

The PX1011A-EL1/G implements a complete PCIe 1.1 Base Specification-compliant PHY stack: CDR-based bit-rate recovery from 2.5 Gbit/s differential serial stream, 8-bit parallel PXPIPE interface at 250 MHz with source-synchronous TXCLK/RXCLK, and integrated analog I/O for PCIe signaling (RX_P/RX_N/TX_P/TX_N). Its architecture includes dedicated elastic buffer for ±600 ppm clock tolerance compensation and hardware-level SKP symbol insertion/removal.

It supports three distinct power states-P0 (full operation), P0s (transmit idle), and P1 (both lanes idle)-with precise PHYSTATUS signaling for state transition completion, and uses separate 1.2 V (VDD), 1.25 V (VDDD3/VDDA1), 2.5 V (VDDD2), and 3.3 V (VDDD1/VDDA2) supplies to isolate analog SerDes, digital core, and I/O domains. JTAG (IEEE 1149.1) enables boundary scan and BIST at-speed validation of SerDes and I/O blocks.

Key Specifications

Pinout & Package

LFBGA81 package (9 × 9 × 1.05 mm, SOT643-1); lead-free SnAgCu solder ball compound; 81-ball fine-pitch array with defined index area (ball A1).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PCIe Gen1 PHY applications.

Compared with IDT8N34S2101 and TI TSB582, the PX1011A-EL1/G provides superior testability via JTAG BIST, tighter EMI control through spread spectrum support, and more flexible link training via polarity inversion and direct disparity control-making it preferred for high-reliability embedded and test equipment applications.

Availability

PX1011A-EL1/G is available at Aetrix Electronics and suitable for industrial backplane interconnect, FPGA-based PCIe bridge designs, and legacy system upgrades requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for PX1011A-EL1/G 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

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications-with roots in Philips Semiconductors' high-performance interface IP.

The PX1011A-EL1/G belongs to NXP's legacy PCIe PHY product line, engineered specifically for FPGA-centric embedded systems needing standards-compliant, off-chip physical layer bridging without integrated MAC logic.

FAQ

What is the operating temperature range for the PX1011A-EL1/G?

The PX1011A-EL1/G is specified for commercial temperature operation from 0 °C to +70 °C. This is confirmed in Table 2 of the official datasheet under "Ordering information" and Table 1 under "Quick reference data." The industrial variant PX1011AI-EL1/G extends this to −40 °C to +85 °C, but the PX1011A-EL1/G itself is rated strictly for the commercial range. Thermal derating is not supported beyond these limits.

Does the PX1011A-EL1/G support PCIe Gen2 or higher data rates?

No, the PX1011A-EL1/G supports only PCIe Gen1 at 2.5 Gbit/s. The datasheet explicitly states compliance with PCI Express Base Specification Rev. 1.0a and Rev. 1.1-both Gen1 standards-and all timing, voltage, and architectural details (e.g., 250 MHz PXPIPE clock, 8b/10b coding, 100 MHz REFCLK) are fixed for Gen1 operation. It does not implement Gen2 features such as 5 GT/s rate, 128b/130b encoding, or modified equalization.

How is clock domain crossing handled between the MAC and PX1011A-EL1/G?

The PX1011A-EL1/G uses source-synchronous clocking: TXCLK (driven by MAC) clocks all transmit-side inputs, and RXCLK (generated by PX1011A-EL1/G) clocks all receive-side outputs. This eliminates asynchronous FIFOs and guarantees deterministic timing-RXCLK's rising edge is aligned to the center of valid RXDATA, and TXCLK's rising edge is expected to be centered on TXDATA. The elastic buffer handles long-term frequency drift, not short-term skew.

Can the PX1011A-EL1/G operate without an external 100 MHz reference clock?

No-the PX1011A-EL1/G requires a differential 100 MHz REFCLK_P/REFCLK_N input with ±300 ppm tolerance. There is no internal oscillator or PLL capable of generating the required bit-rate clock from another source. The device will not achieve CDR lock or enter functional states (e.g., P0) without stable REFCLK applied prior to RESET_N deassertion, as specified in Section 8.4 "Reset."

What power supply voltages does the PX1011A-EL1/G require?

The PX1011A-EL1/G requires five distinct supply rails: VDD = 1.2 V (high-speed serial I/O), VDDD3 = 1.25 V (core logic), VDDD2 = 2.5 V (SSTL_2 I/O), VDDD1 = 3.3 V (JTAG I/O), and VDDA2 = 3.3 V / VDDA1 = 1.25 V (analog SerDes). These are explicitly listed in Table 12 "PCI Express PHY power supplies" and must be independently regulated and decoupled per the layout guidelines in the datasheet.