The CMX602B 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 systems. It also meets the requirements of emerging Caller Identity with Call Waiting services (CIDCW). The device includes a 'zero-power' ring or line reversal detector, a dual-tone (2130Hz plus 2750Hz) Tone Alert Signal 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 Controller. It is suitable for use in systems to BT specifications SIN227 and SIN242, Bellcore GR-30-CORE and SR-TSV-002476, CCA TW/P&E/312, ETSI ETS 300 659 parts 1 and 2, ETS 300 778 parts 1 and 2 and Mercury Communications MNR 19.