Patent ID: 8289080

Claim:
A current-mode amplifier, comprising: an input stage, having an input terminal for receiving an input current of the current-mode amplifier, wherein the input stage generates an inner current according to the input current and a feedback current, and the input terminal of the input stage comprises a first input terminal and a second input terminal, an output terminal of the input stage comprises a first output terminal and a second output terminal, and the input stage comprises: a first current source; a second current source; a first transistor, having a first end connected to a first end of the first current source and the first input terminal of the input stage, and a control end being controlled by the feedback circuit; a second transistor, having a first end connected to a first end of the second current source and the second input terminal of the input stage, and a control end being controlled by the feedback circuit; a third transistor, having a first end connected to a second end of the first transistor, and a control end connected to the first end of the third transistor, wherein a common node of the third transistor and the first transistor is connected to the first output terminal of the input stage; and a fourth transistor, having a first end connected to a second end of the second transistor, and a control end connected to the first end of the fourth transistor, wherein a common node of the fourth transistor and the second transistor is connected to the second output terminal of the input stage; an output stage, having an input terminal connected to the output terminal of the input stage, and an output terminal serving as an output terminal of the current-mode amplifier; and a feedback circuit, having an input and an output terminals connected to the input stage, for generating the feedback current according to the inner current of the input stage.