Datasheet Summary
DTMF GENERATOR
DS3125-2.0 June 1993
The MV5087 is fabricated using ISO-CMOS high density technology and offers low power and wide voltage operation. An inexpensive 3.58MHz TV crystal pletes the reference oscillator. From this frequency are derived 8 different sinusoidal frequencies which, when appropriately mixed, provide Dual-Tone Multi-Frequency (DTMF) tones.
Inputs are patible with either a standard 2-of-8 or a single contact (form A) keyboard. The keyboard entries determine the correct division of the reference frequency by the row and column counters.
D-to-A conversion, using R-2R ladder networks, results in a staircase approximation of a sinewave with low total...