方案描述：

Design your networking equipment with Broadcom's proven Fast Ethernet transceiver technology. Broadcom's industry leading 10/100 BASE-T Ethernet transceiver chips offer the lowest power, smallest footprint, proven interoperability and advanced features, making it easier and less expensive to build Fast Ethernet network interface cards (NIC), LAN on motherboards (LOM), switches, routers and hubs.

方案设计图：

方案关键器件表：

BCM5221

GENERAL DESCRIPTION

The BCM5221 is a single channel, low-power,10/100BASE-TX/FX transceiver targeting a number ofapplications requiring intelligent power management androbust network tolerance. The BCM5221 operates at3.3V or 2.5V. The devices contain a full-duplex 10BASE-T/100BASE-TX/100BASE-FX Fast Ethernet transceiver,which performs all of the physical layer interface functionsfor 10BASE-T Ethernet on CAT 3, 4, and 5 unshieldedtwisted pair (UTP) cable and 100BASE-TX Fast Etherneton CAT 5 UTP cable. In addition, layout compatibility withthe previous generation BCM5201 shortens the designcycle for the BCM5221. 100BASE-FX is supportedthrough the use of external fiber-optic transmit andreceive devices.

The BCM5221 is a highly integrated solution combining adigital adaptive equalizer, ADC, phase lock loop, linedriver, encoder, decoder and all the required supportcircuitry into a single monolithic CMOS chip. It compliesfully with the IEEE 802.3u specification, including theMedia Independent Interface (MII) and Auto-Negotiationsubsections.

The effective use of digital technology in the BCM5221design results in robust performance over a broad rangeof operating scenarios. Problems inherent to mixed-signal implementations, such as analog offset and on-chip noise, are eliminated by employing field provendigital adaptive equalization and digital clock recoverytechniques.

FEATURES

•Power supply: 2.5V or 3.3V 

•Integrated voltage regulator to allow operation from a singlesupply source 

•Power consumption: <275 mW 

•Unique energy detection circuit to enable intelligent powermanagement

•HP auto-MDIX •Cable length indication

•Cable noise level indication•Robust CESD tolerance 

•Cable length greater than 140 meters

•Well under 10 PPM defect ratio quality

•+/-10% voltage tolerance 

•Industrial temperature range (-40 to 85C)

•MII and RMII configurable 

•IEEE 1149.1 (JTAG) scan chain support

•MII management via serial port

•Layout-compatible with BCM5201 

•10BASE-T/100BASE-TX/FX IEEE 802.3u fast Ethernettransceiver 

•Glueless TX-to-FX media conversion

•64-pin TQFP or 64-pin BGA package

APPLICATIONS

•PCMCIA/CardBus cards 

•LAN on motherboard

•IP phones  

•Cable modems  

•Set-top boxes and print servers•Wireless access points

• Embedded telecom