This circuit is from 1980s documentation. The maximum operating frequency is 3.5 MHz. The current of the LED can be from 0 to 100 mA. The integrated circuits used are from that time.
This circuit is from 1964 documentation but can be easily implemented based on current components....
This circuit, which can generate voltages up to 25 V, was found in the December 1992 issue of...
Found in National Semiconductor documentation from the 90's, this circuit has an output current of...