Radio-frequency signal amplifier circuit, power amplifier module, front-end circuit, and communication device
AssigneeMurata Manufacturing Co., Ltd.
InventorsReiji Nakajima, Hidenori Obiya
Life of this patent
Estimating the term…
Abstract
A radio-frequency signal amplifier circuit that is used in a front-end circuit and that propagates a radio-frequency transmission signal and a radio-frequency reception signal is described. The amplifier circuit has an amplifier transistor, a bias circuit, a resistor, and an LC series resonance circuit. The LC series resonant circuit has one end that is connected to a node between the resistor and a signal input terminal, and has another end that is connected to a grounding terminal. A resonant frequency of the LC series resonance circuit is included in a difference frequency band between the frequencies of the transmission signal and the reception signal.
Claims15
A radio-frequency signal amplifier circuit of a front-end circuit configured to propagate a radio-frequency transmission signal and a radio-frequency reception signal, comprising:
- an amplifier transistor configured to amplify the radio-frequency transmission signal;
- a bias circuit configured to supply a bias signal to an input terminal of the amplifier transistor;
- a first resistance element having a first end connected to the bias circuit and a second end connected to the input terminal of the amplifier transistor;
- and
- an inductance-capacitance (LC) series resonance circuit having a first end connected to a node between the first resistance element and the input terminal and a second end connected to a ground terminal, the LC series resonant circuit comprising an inductor and a capacitor that are connected in series to each other,
- wherein a resonant frequency of the LC series resonance circuit is in a difference frequency band representing a difference between a frequency band of the radio-frequency transmission signal and a frequency band of the radio-frequency reception signal.
Dependencies are inferred from the claim text.