System and method for generating a reference voltage

A method comprising:

• applying a supply voltage to a circuit;
• generating a first voltage component, the first voltage component having a positive temperature coefficient;
• generating a second voltage component, the second voltage component being dependent on one or more circuit variables;
• generating a third voltage component, the third voltage component tending to be equal and opposite in sign to the second voltage component;
• generating a fourth voltage component, the fourth voltage component having a negative temperature coefficient, and the positive temperature coefficient and the negative temperature coefficient tending to be equal in magnitude at a predetermined temperature;
• and
• summing the first, the second, the third, and the fourth voltage components to generate a reference voltage, the reference tending to be independent of the circuit variables and a temperature coefficient of the reference voltage tending to zero at the predetermined temperature.

A circuit comprising:

• a first transistor, the first transistor having a first collector, a first base, and a first emitter, the circuit adapted to generate a first collector current, a first base current, and a first emitter current;
• a second transistor, the second transistor having a second collector, a second base, and a second emitter, the circuit adapted to generate a second collector current, a second base current, and a second emitter current;
• a third transistor, the third transistor having a third collector, a third base, and a third emitter, the circuit adapted to generate a third collector current, a third base current, and a third emitter current;
• a base resistor, the base resistor having a base resistor first terminal and a base resistor second terminal;
• a first resistor, the first resistor having a first resistor first terminal and a first resistor second terminal;
• and
• a second resistor, the second resistor having a second resistor first terminal and a second resistor second terminal;
• wherein:
• the first base is coupled to the first terminal of the base resistor, the second terminal of the base resistor is coupled to the second base, the second emitter is coupled to the first terminal of the first resistor, and the second terminal of the first resistor is coupled to the first emitter to form a loop,
• the first collector is adapted to be coupled to a first current source generating the first collector current and the second collector is adapted to be coupled to a second current source generating the second collector current,
• the first terminal of the second resistor is adapted to be coupled to a third current source, the second terminal of the second resistor is coupled to the third collector, the third collector is coupled to the third base, and the third emitter is coupled to the second terminal of the first resistor,
• the second terminal of the second resistor is coupled to the first base, and
• the circuit is adapted to generate a reference voltage at the first terminal of the second resistor.