ISDN Universal Digital Loop Transceiver II - Leader

The MC145421 and MC145425 UDLTs are high-speed data transceivers capable of providing 160 kbps full-duplex data communication over 26 AWG and larger twisted-pair cable up to 1 km in length. These devices are primarily used in digital subscriber voice and data telephone systems. In addition, the devices meet and exceed the CCITT recommendations for data transfer rates of ISDNs on a single twisted pair. The devices utilize a 512 kbaud MDPSK burst modulation technique to supply the 160 kbps full-duplex data transfer rates. The 160 kbps rate is provided through four channels. There are two B channels, which are 64 kbps each. In addition, there are two D channels which are 16 kbps each.

The MC145421 and MC145425 UDLTs are designed for upward compatibility with the existing MC145422 and MC145426 80 kbps UDLTs, as well as compatibility with existing and evolving telephone switching hardware and software architectures.

The MC145421 (Leader) UDLT is designed for use at the telephone switch line card while the MC145425 (Follower) UDLT is designed for use at the remote digital telset or data terminal.