This circuit was found in a 1980s Intersil documentation. The integrated circuit used is not common today. The power supply must be symmetrical.
This circuit is from the 80's component manual itself, but can be applied to more modern...
New Low-Power PIC24 “GA7” Microcontroller Family Now Available CHANDLER, Ariz., Dec. 12, 2016 — The...
The JFETs of this old circuit admit modern equivalents and their characteristics determine the maximum...