BCM5389KFBG

Overview

The BCM5389KFBG is an eight-port Gigabit Ethernet switch IC designed for SOHO and subnetwork applications. It integrates a non-blocking 9-Gigabit Ethernet switch fabric, nine MACs compliant with IEEE 802.x standards, and eight SGMII/SerDes interfaces. The device features a 128-KB packet buffer memory and supports jumbo frames up to 9 KB. Electrical specifications include a 1.2 V CMOS core voltage with power consumption under 1.5 W. It offers SPI interface configuration, 4k VLAN support, and port-based rate control with 64 kbps granularity. The component is housed in a 256-pin FBGA package measuring 17 mm x 17 mm.

Feature Summary

• Integrates eight SerDes cores for direct backplane or fiber optic connections alongside nine IEEE-compliant MACs.
• Supports advanced traffic management including 802.1p QoS, DiffServ, and per-port rate control.
• Enables flexible connectivity through multiple MII interface modes (RvMII, RGMII, GMII) for CPU integration.
• Provides comprehensive switching capabilities such as Spanning Tree, Rapid Spanning Tree, and MAC-based trunking.

Applications

• Standalone Gigabit Ethernet switches for small office/home office environments
• Gigabit Ethernet control plane and backplane applications
• Enterprise branch office networking equipment

Procurement Notes

Verify the specific ordering suffix KFBG against official Broadcom documentation to confirm package type and temperature range. Confirm current lifecycle status, as this component may be subject to end-of-life notifications. Ensure compliance with RoHS and REACH requirements by checking the latest environmental declarations provided by the manufacturer before finalizing procurement plans.

Selection Notes

Select this component when designing cost-effective Gigabit Ethernet switches requiring integrated SerDes and minimal external components. It is suitable for applications needing high port density within a small form factor. Consider the 1.2 V supply requirement and low power profile for fanless designs. Verify that the required interface modes align with the available GMII/RGMII/RvMII options on the ninth MAC.

Part Context

The BCM5389 belongs to Broadcom's eighth-generation SwitchC controller family. It represents a highly integrated solution combining switch fabric, packet buffering, and media access controllers into a single CMOS device. This generation focuses on reducing system complexity and board space while maintaining full IEEE 802.3 compliance for interoperability with standard Ethernet devices.

Replacement Considerations

Consult official Broadcom obsolescence notices for confirmed replacement part numbers. No specific substitute models are documented in the provided source material. Verify compatibility if considering alternative vendors, as pinouts and electrical characteristics may differ significantly across manufacturers.