ISDN U-Interface Transceiver II

The MC145572 U-Interface Transceiver is a single-chip device for Integrated Services Digital Network Basic Access Interface that conforms to the American National Standard ANSI T1.601-1992 and ETSI ETR 080. The device, which can be configured for LT (Line Termination) or NT (Network Termination) applications, performs all necessary Layer 1 functions while utilizing 2B1Q line coding.

The MC145572 can operate in many different modes. The control of these various modes is provided via special purpose pins and the Serial Control Port (SCP) or the Parallel Control Port (PCP):

• The SCP conforms to the NXP^® Serial Control Peripheral Interface standard, an industry standard serial microprocessor interface.
• The PCP is a standard microprocessor bus port.
• The designer may choose between using GCI or the NXP IDL-type time division 2B+D data interface.

A time slot assigner is also provided on the MC145572.

The customer data crossing the U Reference Point consists of two 64 kbps "B" channels and one 16 kbps "D" channel in each direction. Maintenance and framing overhead is also included, for a total 160 kbps data (80 kbaud signaling) rate.