This circuit is from a 1968 documentation using one of the first integrated circuits available at the time, the TAA370. The circuit is powered by 1.3 V using a 200 ohm handset.
This circuit was found in an application note of the LTC1164 from Linear Technology of the 1990s....
This micropower inverter serves to obtain high voltages with very low current from direct current...
This circuit shows how to get 5 V under low current from an operating amplifier 741. I got this...