The FX602 is a low power CMOS integrated circuit for the reception of the physical layer signals used in BT's Calling Line Identification Service (CLIP), Bellcore's Calling Identity Delivery system (CID), the Cable Communications Association's Caller Display Services (CDS), and similar evolving services. It also meets the requirements of emerging Caller Identity with Call Waiting services. The device includes a 'zero-power' ring or line polarity reversal detector, a dual-tone (2130Hz plus 2750Hz) Tone Alert Signal detector and a 1200-baud FSK V23/Bell202 compatible asynchronous data demodulator with a data retiming circuit which removes the need for a UART in the associated C. It is suitable for use in systems to BT specifications SIN227 and SIN242, Bellcore TR-NWT-000030 and SRTSV-002476, CCA TW/P&E/312, ETSI ETS 300 659 parts 1 and 2, and Mercury Communications MNR 19.