The A5191HRT is a single-chip, CMOS modem for use in highway addressable remote transducer (HART) field instruments and masters. The modem and a few external passive components provide all of the functions needed to satisfy HART physical layer requirements including modulation, demodulation, receive filtering, carrier detect, and transmit-signal shaping. The A5191HRT is pincompatible with the SYM20C15. See the Pin Description and Functional Description sections for details on pin compatibility with the SYM20C15.