Microchip Technology PM5326-FEI

Overview

PM5326-FEI from PMC-Sierra is a dual SONET/SDH framer/aggregator IC designed for OC-48 and OC-192 transport layer systems, delivering 20 Gbit/s aggregate capacity with independent STS-192/STM-64 or quad STS-48/STM-16 configuration per framer, supporting SFI-4 LVDS interfaces at 16 × 622 Mbit/s, and enabling channelized STS-1 to concatenated STS-3c×N traffic grooming in MSPP and DWDM line cards.

For engineers reviewing the PM5326-FEI datasheet, PM5326-FEI pinout, PM5326-FEI application, or PM5326-FEI equivalent, key selection considerations include dual-framer configurability, ESSI-based APS interface support, STS-1 granularity pointer processing, B1/B2/B3 error detection, and 1292-pin FCBGA package compatibility with high-density optical line card layouts.

Technical Context

The PM5326-FEI integrates two independent framer cores, each supporting either one STS-192/STM-64 stream or four STS-48/STM-16 streams via OIF SFI-4 interfaces operating at 622 MHz (16-bit LVDS). It implements full SONET/SDH Section, Line, and Path overhead termination with STS-1 frame alignment and pointer processing.

It provides dual sets of working/protect/APS interfaces using four 2.488 Gbit/s ESSI RASIO 3G links per set, supports in-band status messaging over ESSI ports, and includes dedicated STS-1 Memory Switching Units for TSI/muxing in both main and DROP APS paths - enabling local traffic termination and line-card pairing without external switching fabric.

Key Specifications

Pinout & Package

PM5326-FEI is housed in a 1292-pin Fine-Pitch Ball Grid Array (FCBGA) package with 35 × 35 mm body size, 0.8 mm ball pitch, and thermal lid for high-power SONET/SDH transport applications. Pin functions are organized into SFI-4 data/control banks, ESSI APS link groups, DCC extraction/insertion terminals, and JTAG test access.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SONET/SDH framer/aggregator applications.

Compared with PM5326-FEI, PM5376-TSE Nx160 offers higher lane count but less on-die APS flexibility, while PM5377-TSE 240 adds OTN capability at the cost of increased complexity and no native STS-1 MSU for local grooming - making PM5326-FEI optimal for OC-48/OC-192 MSPP and ADM line cards requiring embedded protection and traffic localization.

Availability

PM5326-FEI is available at Aetrix Electronics and suitable for Multi-Service Provisioning Platforms (MSPP), Add/Drop Multiplexers (ADM), and DWDM terminal equipment requiring stable component supply, long-lifecycle support, and qualified optical transport silicon.

Supply support for PM5326-FEI 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

PMC-Sierra (now part of Microsemi, acquired by Microchip Technology) was a fabless semiconductor company specializing in storage, optical networking, and mobile infrastructure ICs, headquartered in Sunnyvale, CA.

The PM5326-FEI belongs to PMC-Sierra's ARROW family of SONET/SDH transport framers, engineered specifically for high-reliability, low-latency optical line cards in carrier-grade MSPP and ADM systems.

FAQ

What is the primary function of the PM5326-FEI in optical transport systems?

The PM5326-FEI serves as a dual SONET/SDH framer and aggregator, enabling OC-48 and OC-192 line-rate processing with independent configuration per framer. It performs full overhead termination, STS-1 alignment, pointer processing, and APS control. The PM5326-FEI integrates memory switching units for traffic grooming and supports ESSI-based protection switching - all critical for carrier-grade MSPP and ADM applications.

Does the PM5326-FEI support both SONET and SDH standards simultaneously?

Yes, the PM5326-FEI natively supports both SONET (STS-192/STS-48) and SDH (STM-64/STM-16) framing formats within the same hardware. It detects and adapts to traffic configuration changes automatically, including concatenated and arbitrarily concatenated (STS-3c×N) modes. The PM5326-FEI processes section, line, and path overhead identically across both standards, ensuring interoperability in mixed-network deployments.

How does the PM5326-FEI handle Automatic Protection Switching (APS)?

The PM5326-FEI implements hardware-based APS using two independent ESSI port sets (W1/P1 and W2/P2), each with four 2.488 Gbit/s RASIO 3G links. It performs K1/K2 byte filtering, BER monitoring, and alarm reporting (SD/SF) without host CPU involvement. The PM5326-FEI also supports direct line-card APS connections and in-band status messaging over ESSI, simplifying system-level protection architecture.

What package type and pin count does the PM5326-FEI use?

The PM5326-FEI is packaged in a 1292-pin Fine-Pitch Ball Grid Array (FCBGA) with 35 × 35 mm body size and 0.8 mm ball pitch. This package supports high-speed signal integrity for dual SFI-4 interfaces and multiple ESSI differential pairs. Thermal design includes an integrated lid, and pin assignments are grouped by functional domain - SFI-4, ESSI APS, DCC/TOH, and JTAG - to simplify PCB layout for optical line cards.

Can the PM5326-FEI operate in line-to-line pass-through mode?

Yes, the PM5326-FEI supports line-to-line mode where SFI-4 receive streams are routed directly to SFI-4 transmit outputs, enabling OC-192 or OC-48 passthrough. In this mode, it can still independently add/drop traffic to/from working and protect system interfaces using its STS-1 MSUs. The PM5326-FEI maintains full overhead transparency and APS functionality during pass-through, making it suitable for transparent regenerators and wavelength-aware muxponders.