Back to results
US 2003/0117210 A1Published application
Current-source circuit
AssigneeKoninklijke Philips Electronics N.V.
InventorJochen Rudolph
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeKoninklijke Philips Electronics N.V.
InventorJochen Rudolph
Estimating the term…
In a current-source circuit in which a first and a second MOS field-effect transistor form a current mirror circuit, wherein a reference current can be supplied to the first MOS field-effect transistor via a third MOS field-effect transistor 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, the source electrodes of the third and of the fourth MOS field-effect transistors are connected to inputs of an automatic gain control amplifier whose output is connected to the gate electrode of the fourth MOS field-effect transistor. The fourth MOS field-effect transistor is an extended-drain MOS field-effect transistor. The drain electrode and the gate electrode of the fourth MOS field-effect transistor are connected to one another via a further MOS field-effect transistor whose gate electrode is acted on by an operating voltage for the circuit.
A current-source circuit in which a first and a second MOS field-effect transistor form a current mirror circuit, wherein a reference current can be supplied to the first MOS field-effect transistor via a third MOS field-effect transistor 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.
A current-source circuit as claimed in any one of the preceding claims, characterized in that the output of the automatic gain control amplifier (7) is connected to the gate electrode of the fourth MOS field-effect transistor (4) via a resistor (8).
A current-source circuit as claimed in any one of the preceding claims, characterized in that the automatic gain control amplifier is formed by an operational transconductance amplifier (7).
Dependencies are inferred from the claim text.