O V ERVI EW

®

Phone: 949-450-8700

Fax: 949-450-8710

E-mail: info@broadcom.com

Web: www.broadcom.com

BROADCOM CORPORATION

16215 Alton Parkway, P.O. Box 57013

Irvine, California 92619-7013

© 2006 by BROADCOM CORPORATION. All rights reserved.

5248-PB01-R

04/17/06

the trademarks of Broadcom Corporation and/or its affiliates in the United States, certain other countries

and/or the EU. Any other trademarks or trade names mentioned are the property of their respective

owners.

BCM5248 Reference Design

The Broadcom BCM5248 is a single-chip device containing eight

independent Fast Ethernet transceivers. Each performs all of the physical

layer functions for 100BASE-TX full- or half-duplex Ethernet on

category 5 UTP cable and 10BASE-T full- or half-duplex Ethernet on

category 3, 4, or 5 UTP cable. The BCM5248 chip performs encoding

and decoding, clock and data recovery, digital adaptive equalization, line

transmission, carrier sense and link integrity monitoring, auto-

negotiation and SMII/SSSMII management functions. The BCM5248 is

compliant with the IEEE 802.3 standard.

The BCM5248 offers alternative connection to fiber optic modules for

100BASE-FX operation. The enhanced FX mode allows 100BASE-FX

operation without the use of signal detect pins. The standard FX mode

allows 100BASE-FX operation with modules that require the PHY to

use signal detect inputs to disable receive data in the absence of a

received optical signal.

The BCM5248 can be connected to a switch controller through the SMII

or SSSMII on one side and to the network media on the other side

through isolation transformers. The BCM5248 operates from 1.8 and

2.5V/3.3V power supplies; the I/O operates at either 2.5V or 3.3V.

The BCM5248 contains an advanced cable diagnostic capability to

detect shorts or opens in a UTP cable and the distance to the fault,

allowing system administrators to quickly determine the source of a

fault. Additionally, the BCM5248 can detect the length of a good,

operating link, which allows mapping of an entire physical cable plant.

The BCM5248 includes support for HP Auto-MDIX which enables the

transceiver to automatically detect and correct cable that is wired

incorrectly. With the HP Auto-MDIX feature, all ports on a switch can

be connected to any other 10/100 port on any switch, hub, or network

interface card, using crossover or straight-through cables

interchangeably. This makes installation, debugging, and maintenance

of the network simpler and less expensive to the end user.

In addition to two fully programmable LED driver pins per port, the

BCM5248 also supports a serial LED driver output that can be used to

drive up to eight LEDs per port, to indicate the status of link, speed,

duplex, transmit or receive activity, or arbitrary functions programmed

by the user. The BCM5248 is offered in a 128 PQFP and a 256-ball BGA

package.

TXD(1:8)

SSYNC

SSSMII_TXC

MII

to

SMII

SSSMII_RXC

SSSMII_RSYNC

SLED_D0

LED2{1:8}

MDIO

MDC

Multimode

Xmt DAC

ADC

10BASE-T

PCS

100BASE-X

PCS

HP

Auto-

MDIX

TD+/-

RD+/-

REF_CLK

SD+/-

BIAS

JTAG

LED

Controller

TXD[3:0]

TXEN

TXER

TXC

COL

RXC

CRS

RXDV

RXER

RXD[3:0]

Cable

Auto-Check

CRS/Link

Detection

Clock

Generator

JTAG

TAP+BS

Bias

Generator

Clock

Recovery

Auto-

Negotiation/

Link Integrity

Digital

Adaptive

Equalizer

MII

Management

Control

MII

Registers

RXD(1:8)

LED1{1:8}

LED_CLK

BCM5248