M-991
Call Progress Tone Generator
Features Generates standard call progress tones Digital input control Linear (analog) output Power output capable of driving standard line 14-pin DIP and 16-pin SOIC package types Single supply 5V CMOS (low power) Inexpensive 3.58 MHz time base Temperature range from -25ºC to 70ºC (-01 version) Temperature range from -40º...