For Gigabit 10/100/1000 Ethernet applications, the GPHY is a highly integrated single chip. It is a singleport, IEEE 802.3u/ab compatible, power efficient Giga Ethernet physical layer transceiver. It can operate in 10BASE Te, 100BASE-TX, and 1000BASE-T modes. This GPHY uses either RGMII or GMII to connect to the Media Access Control Layer (MAC). It could support UTP5/UTP3 cable for 10BASE-Te Ethernet or Unshielded Twisted Pair Category 5 Cable (UTP5) for 100BASE-TX Fast Ethernet and 1000BASE-T Giga Ethernet. It includes the Physical Coding Sublayer (PCS), Physical Medium Attachment Layer (PMA), and Twisted Pair Physical Medium Dependent Sub-layer (TP-PMD, 100BASE-TX only) as well as all of the physical layer functionality for 1000BASE-T as described by IEEE 802.3ab and 100BASE-TX, respectively. Additionally, this GPHY has a strong automated negotiation feature, automatic media speed- duplex selection, and protocol selection.