Semiconductor circuits capable of mitigating unwanted effects caused by input signal variations
AssigneeMediatek Inc.
InventorsSy-Chyuan Hwu, Chih-Chien Hung
Life of this patent
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Abstract
Semiconductor circuit capable of mitigating unwanted effects caused by variations in a received input signal are provided, in which a main circuit receives an input signal and comprises a first current source coupled between a first node and a first power voltage to generate a first current according to a first bias voltage. A replica circuit is coupled to the main circuit to duplicate a variation in a voltage at the first node caused by a variation in the input signal and dynamically adjusts the first bias voltage according to the duplicated variation such that the first current is maintained at a constant.
Claims9
A semiconductor circuit, comprising:
- a main circuit receiving an input signal and comprising:
- a first current source coupled between a first node and a first power voltage to generate a first current according to a first bias voltage;
- and
- a replica circuit coupled to the main circuit to duplicate a distortion current through the first current source caused by a variation in the input signal and output the duplicated distortion current to the main circuit such that an output current of the main circuit is maintained at a constant, the replica circuit including a level shifter configured to level shift a second bias voltage of the replica circuit, the level shifter being coupled to the main circuit.
A method for mitigating current variation in a semiconductor circuit, in which the semiconductor circuit comprises a main circuit receiving an input signal and comprising a first current source coupled between a first node and a first power voltage, the method comprising:
- duplicating, by a replica circuit, a distortion current through the first current source caused by a variation in the input signal;
- adjusting, by a level shifter, a bias voltage of the replica circuit, the level shifter being coupled to the main circuit;
- and
- outputting the duplicated distortion current to the main circuit such that an output current of the main circuit is maintained at a constant.
A semiconductor circuit, comprising:
- a main circuit receiving an input signal and comprising a first current source coupled between a first node and a first power voltage to generate a first current according to a first bias voltage;
- and
- a replica circuit coupled to the main circuit configured to duplicate a distortion current through the first current source caused by a variation in the input signal and output the duplicated distortion current to the main circuit such that an output current of the main circuit is maintained at a constant, the replica circuit comprising a differential pair coupled to a constant current source, the replica circuit including a level shifter connected directly to the output of the constant current source, the replica circuit configured to level shift a second bias voltage at the output of the constant current source, the level shifter being coupled to the main circuit.
Dependencies are inferred from the claim text.