1. A differential amplifier with an input port and an output port, said amplifier comprising: first and second current sources; a first differential pair of transistors that each have first and second current terminals which are responsive to a control terminal, said first differential pair arranged with their control terminals coupled to said input port and their first current terminals coupled to said first current source; a second differential pair of transistors that each have first and second current terminals which are responsive to a control terminal, said second differential pair arranged with their first current terminals coupled to said second current source and their second current terminals coupled to said output port wherein the second current terminal of each of the transistors of said second differential pair is coupled through a respective coupling path to the control terminal of the other transistor of said second differential pair; a first load resistor coupled to the second current terminal of a first one of the transistors of said first differential pair; and a coupling transistor that has first and second current terminals which are responsive to a control terminal, said coupling transistor arranged with its first current terminal coupled to said output port and its control terminal coupled to said second current terminal of said first transistor of said first differential pair.