NT91214

( DataSheet : www.DataSheet4U.com ) NT91214/15 Series Tone/Pulse Dialer Features T One touch redial operation T Tone/Pulse switchable T 32 digit capacity for redialing T Automatic mixed redialing (last number redial) of pulse T PABX auto-pause is 2.2 seconds T DTMF Timing: T to DTMF with multiple automatic access pauses Manual dialing: minimum duration for bursts and pauses Redialing: calibrated timing Hands-Free control function T Wide operating voltage range: 2V to 5.5V T Key-in beep tone output T Digits dialed manually after redialing are T T T T cascadable and stored as additional digits for the next redialing Uses inexpensive ceramic resonator (3.58 MHz) Two versions for different telephone systems Built-in power up reset circuit Four extra function keys: flash, pause, redial and DP DTMF mixed dialing or T 4 x 4 (or 2 x 8) keyboard can be used T Low standby current General Description The NT91214/15 is a single-chip, silicon gate, CMOS integrated circuit with an on-chip oscillator for a 3.58MHz crystal or ceramic resonator. It provides a dialing pulse (DP) or dual tone multi-frequency (DTMF) dialing. A standard 4 x 4 matrix keyboard can be used to support either DP or DTMF modes. Up to 32 digits can be saved in the on-chip RAM for redialing. In the DTMF mode, a short minimum tone duration and minimum intertone pause allows rapid dialing. Maximum tone duration depends on the key depression time during manual dialing. Pin Configurations a. 16-Pin Package b. 18-Pin ...