The circuit presented is from the Motorola Linear Databook of 1990. The integrated circuit is a transconductance operating and the power supply need not be symmetrical.
This circuit was obtained in a General Electric documentation from the 80's, and can be used as a...
This circuit appears in various parts of this site and this section, with diverse origins. This is from...
November 2016 - The TL3780 ultra-miniature E-switch touch switches can now be obtained from Mouser...