Amplifier input stage with charge pump supplying a differential transistor pair

An amplifier circuit, comprising:

• a differential transistor pair operating in response to a differential input signal for developing first and second voltages;
• circuit means responsive to said first and second voltages for providing an output signal of the input stage of the amplifier circuit;
• a charge pump coupled for receiving an operating potential from a first power supply conductor and having an output for providing a pump voltage;
• a first current source for providing a predetermined current at an output;
• a first transistor having a base, an emitter and a collector, said base and said collector being coupled together to said output of said first current source, said emitter being coupled to said output of said charge pump;
• a second transistor having a base, an emitter and a collector, said base being coupled to said base and said collector of said first transistor, said emitter being coupled to said output of said charge pump, said collector being coupled to a conduction path of said differential transistor pair;
• and
• an output stage operating in response to said output signal from the input stage for providing an output signal of the amplifier, said output stage being coupled for receiving said operating potential from said first power supply conductor.

An input stage of amplifier circuit, comprising:

• a differential transistor pair operating in response to a differential input signal for developing first and second voltages;
• circuit means responsive to said first and second voltages for providing an output signal of the input stage of the amplifier circuit;
• a charge pump coupled for receiving an operating potential from a first power supply conductor and having an output for providing a pump voltage;
• a first current source for providing a predetermined current at an output;
• and
• a first transistor having a base, an emitter and first and second collectors, said base and said first collector being coupled together to said output of said first current source, said emitter being coupled to said output of said charge pump, said second collector being coupled to said conduction path of said differential transistor pair.