Patent ID: 7863929
Filing Date: 2011-01-04
Classification: H01S,H03H

Abstract:
1. An active back-end termination circuit, comprising: a first resistor including a first terminal and a second terminal; a first transistor including a first source, a first gate and a first drain, and the first gate and the first drain being connected to the second terminal, and a matching unit being formed by connecting the first resistor and the first transistor in series, and the first source being connected to a working voltage V a second resistor including a third terminal and a fourth terminal; and a second transistor including a second source, a second gate and a second drain, and the second source being connected to the fourth terminal, and a second matching unit being formed by connecting the second resistor and the second transistor in series, and the second gate and the second drain being connected to the working voltage V wherein, the first matching unit and the second matching unit are connected to a circuit in parallel by connecting the first terminal and the third terminal to the circuit in parallel; and wherein, the first transistor or the second transistor is applied with a bias voltage by connecting the first terminal and the third terminal to a voltage source, and an impedance of the first matching unit and the second matching unit are changed actively according to the voltage source for matching a load.