Patent ID: 6538496
Filing Date: 2003-03-25
Classification: G05F

Abstract:
A high impedance current mirror comprising:first, second and third transistors of the same conductivity type, each having first and second terminals and a control terminal, the voltage between the control terminal and the first terminal controlling the current flow between the first and second terminals; the first terminals of the first and second transistors being coupled together and through a first current source to a power supply terminal, the second terminal of the second transistor being coupled as a current input; the third transistor having its first terminal coupled to the power supply terminal, its second terminal coupled to a bias current source and to the control terminal of the first transistor, and its control terminal coupled to the second terminal of the second transistor; the control terminal of the second transistor being coupled to a bias voltage; a capacitor coupled between the control terminal and the second terminal of the third transistor; the second terminal of the first transistor being coupled as a current output for the high impedance current mirror, the output current being equal to the current of the first current source minus the input current.