Patent ID: 6690229
Filing Date: 2004-02-10
Classification: G05F

Abstract:
A current-source circuit in which a first and a second MOS field-effect transistor form a current mirror circuit, wherein a reference current is supplied to the first MOS field-effect transistor via a third MOS field-effect transistor receiving an input at the gate and connected in cascode and the drain electrode of a fourth MOS field-effect transistor connected to the second MOS field-effect transistor in cascode forms an output, characterized in that the source electrodes of the third (3) and the fourth (4) MOS field-effect transistors are connected to inputs of an automatic gain control amplifier (7), whose output is connected to the gate electrode of the fourth MOS field-effect transistor (4), in that the fourth MOS field-effect transistor (4) is an extended-drain MOS field-effect transistor and in that the drain electrode and the gate electrode of the fourth MOS field-effect transistor (4) are connected to one another via a further MOS field-effect transistor (10) whose gate electrode is acted on by an operating voltage for the circuit.