A monolithic dual tone multifrequency receiver

1 December 1979

journal article
Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Journal of Solid-State Circuits

Vol. 14 (6) , 991-997
https://doi.org/10.1109/JSSC.1979.1051307

Abstract

A fully integrated DTMF receiver has been fabricated on a single CMOS chip requiring only three external passive components. The circuit combines precision filters, zero crossing detectors and amplitude detectors with digital logic. Switched capacitor techniques are used to implement high-pass, bandpass, and bandstop filters. The receiver architecture and circuit implementation are described.

Keywords

This publication has 7 references indexed in Scilit:

A monolithic dual-tone multifrequency receiver
Published by Institute of Electrical and Electronics Engineers (IEEE) ,1979
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