Patent ID: 7123091

Claim:
A Darlington differential amplifier comprising: a differential pair of Darlington transistors, each Darlington transistor comprising a first transistor and a second transistor connected in cascade to said first transistor, said first transistor being controlled by an externally generated voltage and driving said second transistor, said first and second transistors each comprising first and second conducting terminals, the first conducting terminals being connected together and forming an output node of the amplifier; a first degeneration impedance connected between the second conduction terminals of said second transistors in said pair of Darlington transistors, said first degeneration impedance comprising a pair of impedance elements connected together in series, a capacitor connected in parallel to said pair of impedance elements, and another impedance element connected in series with said capacitor and also connected in parallel to said pair of impedance elements; and a second degeneration impedance connected between the second conduction terminals of said first transistors in said pair of Darlington transistors for reducing harmonic distortion of the amplifier.