MT8841

® CMOS MT8841 Calling Number Identification Circuit Features 1200 baud BELL 202 and CCITT V.23 Frequency Shift Keying (FSK) demodulation Compatible with Bellcore TR-NWT-000030 and SR-TSV-002476 High input sensitivity: -36dBm Simple serial 3-wire data interface eliminating the need for a UART Power down mode Internal gain adjustable amplifier Carrier detect status output Uses 3.579545 MHz crystal or ceramic resonator Single 5V power supply Low power CMOS technology ISSUE 4 May 1995 Ordering Information MT8841AE 16 Pin Plastic DIP MT8841AS 16 Pin SOIC MT8841AN 20 Pin SSOP -40 °C to +85 °C Description The MT8841 Calling Number Identification Circuit (CNIC) is a CMOS integrated circuit providing an interface to various calling line information delivery services that utilize 1200 baud BELL 202 or CCITT V.23 FSK voiceband data transmission schemes. The CNIC receives and demodulates the signal and outputs data into a simple 3-wire serial interface. Typically, the FSK modulated data containing information on the calling line is sent before alerting the called party or during the silent interval between the first and second ring using either CCITT V.23 recommendations or Bell 202 specifications. The CNIC accepts and demodulates both CCITT V.23 and BELL 202 signals. Along with serial data and clock, the CNIC provides a data ready signal to indicate the reception of every 8-bit character sent from the Central Office. The received data can be processed externall...