This series LED circuit was found in the February 1992 issue of Radio Electronics magazine. The effect's speed is dependent on C1 and adjusted by R3.
We found this protection circuit for op amps in the Encyclopedia of Electronic Circuits Volume 5 from...
The use of field effect transistors in this circuit improves its performance. This configuration is from a...
Found in old American documentation, this circuit makes use of operational amplifiers from the 70s...