Microchip Technology PM40100B-FEI

Overview

PM40100B-FEI from Microchip Technology is a PCIe Gen 4 fanout switch IC with 100 lanes, 52 configurable ports, 48 assignable non-transparent bridges (NTBs), 26 virtual switch partitions, and per-port hot- and surprise-plug controllers. It integrates a MIPS processor and supports x1/x2/x4/x8/x16 port bifurcation for data center interconnects, NVMe SSD expansion, and telecom infrastructure.

For engineers reviewing the PM40100B-FEI datasheet, PM40100B-FEI pinout, PM40100B-FEI application, or PM40100B-FEI equivalent, key selection criteria include lane count scalability, NTB assignment flexibility, DPC/AER error containment compliance, real-time eye capture capability, and support for SFF-8644/OCuLink passive and optical cable interfaces.

Technical Context

The PM40100B-FEI implements a non-blocking PCIe Gen 4 switch fabric operating at 16 GT/s with full link training compliance and manual PHY configuration support for optical interconnects. It features integrated AER on all ports and Downstream Port Containment (DPC) on every downstream port to isolate errors without upstream propagation.

Its architecture includes a dedicated ultra-low-latency DMA controller, 11 TWI/SMBus interfaces, up to 4 UARTs, JTAG/EJTAG debug access, and a 10/100 Ethernet MAC (MII/RMII) - though the latter is specified only for PFX 96x/80x/64xG4 variants and excluded from PM40100B-FEI per official ordering table and family documentation.

Key Specifications

Pinout & Package

PM40100B-FEI is housed in a 35 mm × 35 mm, 1156-ball FCBGA package (0.8 mm pitch) with I/O banks optimized for PCIe Gen 4 signal integrity. Pinout information is not publicly disclosed in summary documentation or Microchip's public datasheets for this variant; official pinout requires NDA-protected design files (DS00002866D, Rev D, page 3/20). No verified public pin mapping is available.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Intel PEX8796 and AMD/PLX PEX88024, the PM40100B-FEI delivers unique value in large-scale, fault-tolerant infrastructure through its combination of 100 Gen 4 lanes, 48 NTBs, 26 virtual partitions, and per-port hot-plug - none of which are simultaneously offered by either alternative.

Availability

PM40100B-FEI is available at Aetrix Electronics and suitable for data center NVMe expansion, telecom core routing, defense avionics backplanes, and broadcast video processing requiring stable component supply across long-life industrial programs.

Supply support for PM40100B-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

Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, FPGAs, and connectivity solutions with emphasis on reliability and long-term support.

The Switchtec PFX Gen 4 family - including PM40100B-FEI - was designed for high-availability infrastructure demanding PCIe Gen 4 scalability, hardware-enforced isolation, and comprehensive in-system diagnostics.

FAQ

What is the maximum PCIe lane count supported by the PM40100B-FEI?

The PM40100B-FEI supports up to 100 PCIe Gen 4 lanes, enabling high-bandwidth topologies such as 48 NVMe SSDs or multi-GPU configurations. This lane count is fixed for the PM40100B-FEI variant and cannot be increased via firmware or configuration. Lane allocation is fully programmable across its 52 ports with x1/x2/x4/x8/x16 bifurcation flexibility.

Does the PM40100B-FEI include an integrated processor?

Yes, the PM40100B-FEI integrates a MIPS processor used for switch management, configuration, diagnostics, and secure boot execution. This processor runs Microchip's Switchtec firmware and handles tasks including NTB setup, partition management, and real-time eye capture control - eliminating the need for an external host controller for basic switch operations.

Is the PM40100B-FEI compatible with optical PCIe cables?

Yes, the PM40100B-FEI supports optical PCIe cables via manual PHY configuration and compliance with SFF-8644, OCuLink, and other industry-standard connectors. Its SERDES includes high-quality, low-power design optimized for optical signal integrity, and real-time eye capture allows direct validation of optical link health without external equipment.

What error containment features does the PM40100B-FEI provide?

The PM40100B-FEI implements Downstream Port Containment (DPC) on all downstream ports, Advanced Error Reporting (AER) on all ports, and Completion Timeout Synthesis (CTS) to prevent upstream hosts from entering error states due to incomplete transactions. These features are hardware-enforced and active without host software intervention.

How many virtual switch partitions does the PM40100B-FEI support?

The PM40100B-FEI supports exactly 26 virtual switch partitions, each providing hardware-isolated address spaces, configuration registers, and traffic routing policies. This enables strict multi-tenancy in cloud, defense, and telecom applications where logical separation of workloads is required for security and QoS enforcement.