Title :
A monolithic dual tone multifrequency receiver
Author :
White, Bertram J. ; Jacobs, Gordon M. ; Landsburg, George F.
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 :
Band-pass filters; Field effect integrated circuits; High-pass filters; Switched filters; Telephone receivers; band-pass filters; field effect integrated circuits; high-pass filters; switched filters; telephone receivers; Band pass filters; Capacitors; Circuits; Detectors; Frequency; Jacobian matrices; Large scale integration; Silicon; Telephony;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.1979.1051307
