Try the Clare CPC5621 (http://www.clare.com/Products/LITELINK.htm), which is DAA with hybrid, ring detection, CPC detection, and the ability to pass caller information (for caller ID display, etc.). The sample circuit from their datasheet works well without any changes. Rob ----- Original Message ----- From: "Josh Migeri" To: "Microcontroller discussion list - Public." Sent: Friday, July 29, 2005 1:39 AM Subject: [EE] Telephone Audio signals Differentiator > > Would the pic_list community help me with suggestions on > a circuit that can differentiate between an Telephone > Service provider announcement: e.g "The number you are > calling is unavailable" and a human answering the Telephone > call on the other end. The circuit could be equipped to > identify other Telephone Call Progress tones e.g busy tone, > dial tone, ring tone. > > I would like to use this circuit in a pic-controlled > telephone dialer. > > Many thanks > > Josh > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist