Patent ID: 6657494
Filing Date: 2003-12-02
Classification: H03D,H03F,H03G

Abstract:
An amplifying stage comprising:a differential pair of amplifying transistors having a first output terminal and a second output terminal coupled to corresponding electrodes of first and second transistors in said differential pairs; first and second supply resistors coupled to each said output terminal for connection to a source; a load circuit connected between the differential amplifier and ground; second and third load circuits each connected between said first and second output terminals and ground respectively; and a current divider for connection to a substantially constant current source, providing a current I, said current divider dividing said source current I into first and second currents I1 and I2, a proportion of I1 to I2 being determined by a gain control circuit the current I1 being provided to a first current source load circuit and the current I2 being provided to a second current source load circuit, said first load circuit being connected to said second current load circuit to mirror I2, and said second load circuit being connected to said first current load circuit to mirror I1.