Complementary field effect transistor amplifier

An amplifier, comprising:

• first and second terminals for receiving an operating voltage therebetween;
• first and second complementary field effect transistors having the drain electrodes thereof connected to a circuit output terminal and the gate electrodes thereof connected to a circuit input terminal;
• a third field effect transistor of the same channel conductivity type as said first field effect transistor, the source and drain electrodes thereof being coupled, respectively to said first terminal and to the source electrode of said first transistor;
• first voltage regulating means coupled to the gate electrode of said third transistor for regulating the gate-to-source voltage thereof in accordance with a first input current;
• a fourth field effect transistor of the same channel conductivity type as said second field effect transistor, the source and drain electrodes thereof being coupled, respectively, to said second terminal and to the source electrode of said second transistor;
• second voltage regulating means coupled to the gate electrode of said fourth transistor for regulating the gate-to-source voltage thereof in accordance with a second input current;
• and
• input means for supplying said first and second input currents to said first and second voltage regulating means and for controlling the ratio thereof in response to an input signal applied to said circuit input terminal.

An amplifier, comprising, in combination:

• an input terminal for receiving an input signal, an output terminal for providing an output signal and first and second supply terminals for receiving, respectively, first and second operating voltages;
• first and second field effect transistors of a first conductivity type, each having source, gate and drain electrodes, the gate and drain electrodes of the first transistor being connected respectively, to said input and output terminals, the source and drain electrodes of the second transistor being connected, respectively, to said first supply terminal and to the source electrode of said first transistor;
• third and fourth field effect transistors of a second conductivity type, each having source, gate and drain electrodes, the gate and drain electrodes of the third transistor being connected, respectively, to said input and output terminals, the source and drain electrodes of the fourth transistor being connected, respectively, to said second supply terminal and to the source electrode of said third transistor;
• first means connected to said input terminal and to at least the first of said supply terminals for applying a bias voltage across the gate and source of electrodes of said second transistor in proportion to but less than the potential difference appearing between said first terminal and said input terminal;
• and
• second means connected to said input terminal and to at least the second of said supply terminals for applying a bias voltage across the gate and source electrodes of said fourth transistor in proportion to but less than the potential difference appearing between said second terminal and said input terminal.

An amplifier, comprising:

• first and second field effect transistors of first and second conductivity types, respectively, each having source, gate and drain electrodes, said gate electrodes being connected to a signal input terminal, said drain electrodes being connected to a signal output terminal;
• first and second complementary current mirror amplifiers each having input, common output terminals, said common terminals for receiving an operating voltage thereacross, said output terminals being connected to respective ones of said source electrodes;
• and
• input means for supplying input currents to the input terminals of said current mirror amplifiers and for controlling the ratio thereof in accordance with an input signal applied to said input signal terminal.