MT88E45

The MT88E45B is a low power CMOS integrated circuit suitable for receiving the physical layer signals used in North American (Bellcore) Calling Identity Delivery on Call Waiting (CIDCW) and Calling Identity Delivery (CID) services. It is also suitable for ETSI and BT Calling Line Identity Presentation (CLIP) and CLIP with Call Waiting services.

The MT88E45B contains a 1200 baud Bell 202/CCITT V.23 FSK demodulator and a CAS/DT-AS detector. Two input op-amps allow the MT88E45B to be connected to both Tip/Ring and the telephone hybrid or speech IC receive pair for optimal CIDCW telephone architectural implementation. FSK demodulation is always on Tip/Ring, while CAS detection can be on Tip/Ring or Hybrid Receive. Tip/Ring CAS detection is required for the Bellcore/TIA Multiple Extension Interworking (MEI) and BT's on-hook CLIP. A selectable FSK data interface allows the data to be processed as a bit stream or extracted from a 1 byte on chip buffer. Power management has been incorporated to power down the FSK or CAS section when not required. Full chip power down is also available. The MT88E45B is suitable for applications using a fixed power source (with a +/-10% variation) between 3 and 5 V.