BCM54991ELB0KFEBG

Description

The Broadcom BCM5389 device is a highly integrated solution ideally
suited for standalone Gigabit Ethernet switches and Gigabit Ethernet
control plane and backplane applications. It combines all the functions of
a high-speed switch system, including packet buffer, SerDes, media
access controllers, address management, and a nonblocking switch
fabric into a single 0.13 µm CMOS device.
The BCM5389 complies with IEEE 802.3, 802.3u, 802.3ab, and 802.3x
specifications, including the MAC control, pause frame, and autonegotiation subsections, providing compatibility with all industrystandard Ethernet, Fast Ethernet, and Gigabit Ethernet devices.
The integrated eight SerDes cores enable direct connections across
backplanes with the lowest possible amount of traces. The device also
integrates nine IEEE compliant 10/100/1000 MACs. Eight of these are
internally connected to the SerDes cores offering alternatively true serial
interfaces for backplane connections or fiber optic transceivers or SGMII
interfaces for connection to industry-standard Gigabit Ethernet copper
transceivers such as the Broadcom BCM5464R. The ninth MAC features
multiple MII interface modes (RvMII, RGMII, GMII) for connection to
a variety of CPUs.The media access controllers on the BCM5389 also
support jumbo frames which are typically used for high-performance

connections to servers because they offer a smaller percentage of
overhead on the link for more efficiency.
SPI or EEPROM interfaces provide easy programming of the on-chip
802.1p QoS and/or DiffServ. This allows switch traffic to be given
different classes of priority or service. For example, voice traffic for IP
phone applications, video traffic for multimedia applications, or data
traffic for e-mail applications. Up to 4k virtual LANs (VLANs) can be
set up via the SPI port for separation of different users or groups on the
network. For multi-Gigabit per second connections, multiple ports of the
BCM5389 can be grouped together to form logical links. These links
feature automatic load balancing.
The BCM5389 can also be used in fully managed applications where
support for Spanning Tree and MIB counters is a requirement. In such
applications, the CPU will be connected using the SPI interface for
register control and the ninth MII interface for protocol frames.
Finally, the BCM5389 supports per-port rate control for applications like
MTU/MDU switches where individual ports need to be restricted in
speed to comply with the agreed and paid for service levels.