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.