NT91315XL Description
The NT91315XL series are single-chip silicon gate CMOS integrated circuits with on-chip oscillators to be used with a 3.58 MHz crystal or ceramic resonator. They provide dialing pulse (DP) or dual tone multi-frequency (DTMF) dialing. A 24-key (5x5-1) matrix keyboard is used for either DP or DTMF mode.