TP5087

The TP5087 is designed as one kind of DTMF generators,these tone dialers are low threahold voltage,field-implanted,metal gate CMOS integrated circuits.The devices interface directly to a standard telephone keypad and generate all dual tone multi-frequency pairs required in tone-dialing systems.The tone synthesizers are locked to an on-chip reference oscillator using an inexpensive 3.579545 MHz crystal for high tone accuracy.The crystal and an output load resistor are the only external components required for tone generation.AMUTE OUT logic signal,which changes state when any key is depressed,is also provided.

Features of the TP5087 can be summarized as:(1)2.5V to 10V operation when generating tones(TP5380);(2)2V operation of keyscan and MUTE logic;(3)power directly from telephone line;(4)interfaces with standard single-contact or 2-of-8 telephone keypad;(5)stasic sensing of key closures;(6)on-chip 3.579545 MHz crystal-controlled oscillator;(7)on-chip regulation of tone amplitudes;(8)high group and low group tones generated and mixed internally;(9)high group pre-emphasis;(10)low harmonic distortion;(11)open emitter-follower low-impedance output.

And the absolute maximum ratings of TP5087:(1)supply voltage:15V;(2)maximum voltage at any pin:Vdd+0.3V to Vss-0.3V;(3)operating temperature:-30 to +60;(4)storage temperature:-55 to +150;(5)maximum power dissipation:500 mW.