Sun Microsystems 60 service manual External Transceivers, External Cables, Connectors, MII Power

C.1.12.2 External Transceivers

The following external transceivers are connected through the MII port:

■6211 Micro 100BASE-FX FastEthernet transceiver

■CT4-1030 100BASE-T4 transceiver

■CFX-107X 100BASE-FX transceiver

■XF467A MII-to-AUI transceiver

C.1.12.3 External Cables

The MII port supports a 0.5-meter long, 40-conductor, 20 signal-ground, STP cable. The single-ended impedance of the cable is 68 ohms (+/-10%). The propagation delay for each twisted-pair, measured from the MII connector to the PHY, does not exceed 2.5 nanoseconds.

The RJ45 Ethernet port supports a Category 5, UTP cable for the 100BASE-T, and a Category 3, 4, or 5 UTP cable for the 10BASE-T operation.

Note –The maximum cable segment lengths for the 100BASE-TX and 10BASE-TX are 100 meters and 1000 meters, respectively.

C.1.12.4 Connectors

A40-pin connector is used for the MII connector. A standard 8-pin RJ45 connector with a shield is used for the AUI connector.

C.1.12.5	MII Power
	A regulated 5-Vdc (+/- 5%) voltage is supplied to the PHY IC over the load range of
	from 0 to 750 mA. A 2-amp overcurrent protection circuit is provided by a polymer-
	based resettable fuse to the MII supply voltage.
	MII-to-AUI connection to a 10-Mbps medium attachment unit requires a
	supplemental power source to meet the AUI power supply requirements. The MII-
	AUI converter provides the necessary supplemental power.

C.1.12.6 MII Port Timing

MII port timing encompasses two configurations involving the use of either an on- board transceiver or external transceivers. For either transceiver configuration, the MII port timing is the same because MII operates with a 40-nanosecond cycle time.

C-26Sun Ultra 60 Service Manual • August 2001