BCM5396KFB

Overview

The BCM5396KFB is a single-chip 16-port Gigabit Ethernet switch integrating sixteen 1.25G SerDes/SGMII interfaces for external PHY or fiber module connectivity. It features a 256 KB on-chip packet buffer, address management supporting up to 4K MAC addresses, and an integrated 10/100/1000 Mbps in-band management port (IMP) with GMII/RGMII/RvMII/MII options. The device supports IEEE 802.1Q VLANs, DiffServ QoS with four queues, Spanning Tree protocols, and IEEE 802.1X security. It operates at low power (2.2W total) using a 1.2V core and utilizes a 256-pin FBGA package.

Feature Summary

• Integrates sixteen 1.25G SerDes/SGMII ports for flexible connection to external Gigabit transceivers or fiber modules.
• Includes a 256 KB chip-level packet buffer and hardware-based address management for efficient data forwarding.
• Supports comprehensive Layer 2 features including VLAN tagging, QoS prioritization, and spanning tree redundancy.
• Provides a dedicated in-band management port for direct CPU connection without requiring an external PHY.

Applications

• Desktop switching solutions and WebSmart applications
• Low-cost Gigabit Ethernet infrastructure devices
• Industrial network equipment requiring compact form factors

Procurement Notes

Verify the suffix KFB against official datasheets to confirm package type and temperature range specifications. Ensure compatibility with required voltage levels (1.2V core, 2.5V SGMII I/O, 3.3V MII/GMII) during board design. Confirm SPI interface requirements for configuration and EEPROM access. Validate pinout alignment for the 256-pin FBGA footprint.

Selection Notes

Select this component when a high-density 16-port Gigabit solution is required with minimal external components. The integrated SerDes reduces PCB area compared to parallel RGMII designs. Suitable for applications needing robust L2 features like VLAN and QoS within a low-power envelope. Consider the IMP port availability if direct CPU management is preferred over external PHY connections.

Part Context

The BCM5396 series represents Broadcom's entry into cost-effective, high-density Gigabit switching. It targets the desktop and light industrial segments where space and power efficiency are critical. The KFB variant specifically denotes the package and thermal characteristics within the broader BCM5396 family, sharing identical functional logic with other suffixes.

Replacement Considerations

BCM5389: A similar 16-port Gigabit switch from the same generation with comparable feature sets. Verify pin-to-pin compatibility and register mapping before substitution. Other BCM53xx series chips may offer different port counts or PHY integration levels.