Found in European documentation from the 1980s, this circuit was originally designed for computer applications of the time. However, the basic idea can be adapted for use with microcontrollers.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...