Nortel Networks 553-3001-211 manual NT6D70 Silc Line card Page 371

NT6D70 SILC Line card Page 371 of 894

The transceiver circuits provide four-wire full-duplex S/T bus interface. This bus supports multiple physical terminations on one DSL where each physical termination supports multiple logical B-channel and D-channel ISDN BRI terminals. Idle circuit-switched B-channels can be allocated for voice or data transmission to terminals making calls on a DSL. When those terminals become idle, the channels are automatically made available to other terminals making calls on the same DSL.

The power on the DSL comes from the SILC, which accepts –48 V from the IPE backplane and provides two watts of power to physical terminations on each DSL. It provides -48 V for ANSI-compliant ISDN BRI terminals and –40 V for CCITT (such as ETSI NET-3, INS NET-64) compliant terminals. The total power used by the terminals on each DSL must not exceed

two watts.

Circuit Card Description and Installation