Patent ID: 6121764
Filing Date: 2000-09-19
Classification: G05F

Abstract:
A current source comprising:first, second and third transistors, each having first and second terminals and a control terminal, the conduction through the respective transistor being responsive to the voltage between the control terminal and the first terminal, the first, second and third transistors having their first terminals coupled together and to a first power supply terminal, and their control terminals coupled together, the third transistor having its control terminal coupled to its second terminal to mirror current through the third transistor to the first and second transistors, the current in the second terminal of the first transistor forming a current output of the current source;first and second reference current sources, the first reference current source being coupled to the second terminal of the third transistor and to a second power supply terminal, the second reference current source being coupled to the second terminal of the second transistor and to the second power supply terminal;a first circuit coupling the voltage on the second terminal of the first transistor to the second terminal of the second transistor;a second circuit coupling, with a current gain, and to the second terminal of the third transistor, the difference between the current of the second current source and the current mirrored to the second transistor.