Low-noise wide-band amplifier circuit

Abstract

The invention discloses a circuit of a low-noise broadband amplifier, which comprises a first-stage circuit and a second-stage circuit, wherein the first-stage circuit comprises two phase inverters. Both ends of a differential input signal are respectively connected with the input ends of the two phase inverters. The second-stage circuit also comprises two phase inverters. The output ends of the two phase inverters of the first-stage circuit are respectively connected with the input ends of the two phase inverters of the second-stage circuit. The first-stage circuit and the second-stage circuit are isolated by a current source, the second-stage circuit and a power supply are also isolated by a current source, and the output ends of the two phase inverters of the second-stage circuit are the output ends of the circuit of a low-noise broadband amplifier. The invention uses the two-pole structure of current multiplexing and has excellent stability and high gain performance, and the power consumption is also greatly reduced; the second-stage circuit has the effect of resisting the reverse kick of a back loading circuit, and higher gain is realized.

Description

technical field [0001] The invention relates to a circuit, especially a low-noise broadband amplifier circuit. Background technique [0002] The low-noise broadband amplifier circuit is the front-end module of the RF chip, which requires the characteristics of low noise, high bandwidth, high linearity, high gain, and low power consumption. It is mostly used in FM demodulators, TV demodulators, UWB or other broadband radio frequency in the technical plan. Among the existing low-noise broadband amplifier (LNA) circuit schemes, there are three common ones: [0003] figure 1 The circuit shown is a low-noise broadband amplifier circuit with a common-gate input structure, including an NMOS transistor. The gate of the NMOS transistor is connected to a bias voltage Vbias, the drain is connected to the power supply terminal through a variable resistor Rload, and the source is The resistor Rs is grounded, the end of the resistor Rs connected to the source is used as a signal input ...

AI Technical Summary

Problems solved by technology

[0006] The above-mentioned three kinds of existing low-noise broadband amplifier circuits generally have the disadvantages of large noise figure, high power consumption, poor anti-kickback ability, and are increasingly unsuitable for the requirements of technological development.

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