The integrated circuit used in this 2002 project is not very common. It is powered directly by the telephone line, requiring no power supply.
This circuit was found in an Electronics World of 1969. The circuit has a drain current of...
This circuit makes use of the Linear Technology LT6100. We find it in a 2005 company manual. The...
I found this circuit in an English publication from 1989. This configuration can be mounted with...