The circuit shown in the figure below is from the 1993 Linear Technology Applications. The operational ones used are uncommon and the use of equivalents can be analyzed.
This circuit causes the relay to be energized when the input voltage exceeds the voltage value of...
The circuit we present is suggested by Linear Technologies (www.linear.com) and makes use of an...
Found in American documentation from the 90s, this circuit can be used as a shield with the...