Occasionally it can be useful to generate only the maximum or minimum output of several analog input signals.
The two simple op amp circuits here perform that function for an arbitrary number of inputs.
Below is the LTspice simulation for the max value circuit, shown for three inputs.
As can be seen, the output follows the input with the maximum voltage.
View attachment 105837
By reversing the diodes and connecting the output resistor to V+, the circuit becomes a minimum value...