By Topic

The TDA1077 - An I/sup 2/L circuit for two-tone telephone dialing

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)

The circuit-design aspects of an integrated circuit to perform two-tone telephone dialing are described. The circuit is believed to be unique in that it combines both the crystal-controlled frequency synthesizer and the output amplifier on the same chip. Moreover, no external power supplies are required; the circuit is powered by the telephone-line current. Designed to require a minimum number of external components, the LSI chip provides an economical and accurate two-tone dialing unit. A typical application circuit for existing telephone apparatus is shown and aspects of future development are discussed.

Published in:

Solid-State Circuits, IEEE Journal of  (Volume:12 ,  Issue: 3 )