This circuit was obtained from a Linear Technology manual from the 90's. The integrated circuits are from the time and could possibly be tested as modern equivalents.
Using components from the era, this 90's EDN circuit is used in analog to digital conversion...
Found in an American publication from the 90s, this circuit allows the supply of 3, 6 and 9 V...
We found this circuit in an old Popular Electronics. The circuit is experimental, driving an LED...