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CN-224218365-U - Output matching circuit, low noise amplifying circuit and radio frequency power amplifier module

CN224218365UCN 224218365 UCN224218365 UCN 224218365UCN-224218365-U

Abstract

The utility model provides an output matching circuit, a low-noise amplifying circuit and a radio frequency power amplifier module, wherein the output matching circuit comprises a first capacitor, a first inductor, a second capacitor, a series resonant circuit and a second inductor, the input end of the series resonant circuit is connected to a power supply, and the output end of the series resonant circuit is connected to the second end of the second capacitor. The output matching circuit can form a parallel-series combined mode, so that the output matching circuit has higher bandwidth and out-of-band rejection and better flatness in a pass band.

Inventors

  • Request for anonymity
  • Request for anonymity

Assignees

  • 深圳飞骧科技股份有限公司

Dates

Publication Date
20260508
Application Date
20250411

Claims (8)

  1. 1. An output matching circuit is characterized by comprising a first capacitor, a first inductor, a second capacitor, a series resonant circuit and a second inductor; The first end of the first capacitor is used as an input end of the output matching circuit and is connected to an output end of the low-noise amplifier; The first end of the first inductor is used for being connected to a power supply, and the second end of the first inductor is connected to the first end of the first capacitor; the first end of the second capacitor is used for being connected to a power supply, and the second end of the second capacitor is connected to the second end of the first capacitor; The input end of the series resonance circuit is used for being connected to the power supply, and the output end of the series resonance circuit is connected to the second end of the second capacitor; The first end of the second inductor is connected to the output end of the series resonant circuit, and the second end of the second inductor is used as the output end of the output matching circuit.
  2. 2. The output matching circuit of claim 1, wherein the series resonant circuit comprises a third inductance and a third capacitance; A first end of the third inductor is used as an input end of the series resonant circuit; the first end of the third capacitor is connected to the third inductor, and the second end of the third capacitor is used as an output end of the series resonant circuit.
  3. 3. A low noise amplifying circuit, characterized in that the low noise amplifying circuit comprises a switching unit, a filter, an input matching circuit, a low noise amplifier, and the output matching circuit according to claim 1 or 2; The first end of the switch unit is used for connecting an antenna to realize the opening or closing of a channel for receiving signals; An input terminal of the filter is connected to a second terminal of the switching unit; the input end of the input matching circuit is connected to the output end of the filter; The first input end of the low-noise amplifier is connected to the output end of the input matching circuit and is used for being connected with a first bias voltage, the second input end of the low-noise amplifier is used for being connected with a second bias voltage, the grounding end of the low-noise amplifier is grounded, and the output end of the low-noise amplifier is connected to the input end of the output matching circuit.
  4. 4. The low noise amplifier circuit of claim 3, wherein the low noise amplifier comprises a first field effect transistor and a second field effect transistor; The grid electrode of the first field effect transistor is used as a first input end of the low-noise amplifier, and the source electrode of the first field effect transistor is used as a grounding end of the low-noise amplifier; the grid electrode of the second field effect tube is used as a second input end of the low noise amplifier, the source electrode of the second field effect tube is connected to the drain electrode of the first field effect tube, and the drain electrode of the second field effect tube is used as an output end of the low noise amplifier.
  5. 5. The low noise amplifier circuit of claim 4, wherein the input matching circuit comprises a fourth inductor, a fifth inductor, a fourth capacitor, and a sixth inductor; The first end of the fourth inductor is used as an input end of the input matching circuit, and the second end of the fourth inductor is used as an output end of the input matching circuit; A first end of the fifth inductor is connected to a first end of the fourth inductor, and a second end of the fifth inductor is grounded; The first end of the fourth capacitor is connected to the second end of the fourth inductor, and the second end of the fourth capacitor is connected to the source electrode of the first field effect transistor; the first end of the sixth inductor is connected to the source electrode of the first field effect transistor, and the second end of the sixth inductor is grounded.
  6. 6. The low noise amplifier circuit of claim 3, further comprising a first resistor, a first terminal of the first resistor being coupled to the first input terminal of the low noise amplifier, a second terminal of the first resistor being configured to be coupled to a first bias voltage.
  7. 7. The low noise amplifier circuit of claim 3, further comprising a second resistor, wherein a first terminal of the second resistor is connected to the output terminal of the output matching circuit, and a second terminal of the second resistor is grounded.
  8. 8. A radio frequency power amplifier module, characterized in that the radio frequency power amplifier module comprises a low noise amplifier circuit according to any one of claims 3 to 7.

Description

Output matching circuit, low noise amplifying circuit and radio frequency power amplifier module Technical Field The present utility model relates to the field of wireless communications technologies, and in particular, to an output matching circuit, a low noise amplifying circuit, and a radio frequency power amplifier module. Background A wideband low noise amplifier circuit is an important component of a radio frequency receive front end that is required to provide high gain and low noise over a wide frequency band while suppressing interference with out-of-band signals. The matching circuit of the high-broadband low-noise amplifier circuit is mainly divided into an input matching circuit and an output matching circuit. The input matching circuit is used for efficiently transmitting signals received by an antenna to the input end of the low-noise amplifier circuit, and usually needs to consider the impedance of the antenna and the input impedance of the low-noise amplifier, and also needs to consider the compromise between noise and power matching, and the key link in the design of the output matching circuit is related to whether the amplifier can effectively transmit amplified signals to a subsequent circuit or not, and ensures that the power and the frequency spectrum characteristics of the output signals meet the system requirements, and needs to consider the output impedance of the low-noise amplifier and the input impedance of a next-stage circuit, and usually form conjugate matching with the output impedance of the low-noise amplifier. The wideband output matching of the existing low noise amplifier circuit is usually an LCCL connection mode, that is, a mode of performing series-parallel connection on two inductors and two capacitors, and simultaneously, converting one of the capacitors into a LCtank circuit (a capacitive-inductive series resonant circuit), that is, converting one of the capacitors into a mode of connecting one of the inductors and one of the capacitors in series, or converting the other of the capacitors into a LCtrap circuit (a capacitive-inductive parallel circuit), that is, converting the other of the capacitors into a mode of connecting one of the inductors and one of the capacitors in parallel, so as to achieve the effect of out-of-band suppression. Although the above design method can achieve the out-of-band suppression effect, the out-of-band suppression effect can be achieved only when the existing bandwidth is kept unchanged or even the bandwidth is deteriorated, and the flatness in the passband is poor. Disclosure of utility model Aiming at the defects of the prior art, the utility model provides an output matching circuit, a low-noise amplifying circuit and a radio frequency power amplifier module which are high in bandwidth, high in out-of-band rejection and better in pass band flatness. In order to solve the technical problem, in a first aspect, the present utility model provides an output matching circuit, which includes a first capacitor, a first inductor, a second capacitor, a series resonant circuit, and a second inductor; The first end of the first capacitor is used as an input end of the output matching circuit and is connected to an output end of the low-noise amplifier; The first end of the first inductor is used for being connected to a power supply, and the second end of the first inductor is connected to the first end of the first capacitor; the first end of the second capacitor is used for being connected to a power supply, and the second end of the second capacitor is connected to the second end of the first capacitor; The input end of the series resonance circuit is used for being connected to the power supply, and the output end of the series resonance circuit is connected to the second end of the second capacitor; the first end of the second inductor is connected to the output end of the series resonant circuit, and the second end of the second inductor is used as the output end of the output matching circuit and is used for being connected to a next-stage circuit. Preferably, the series resonant circuit includes a third inductance and a third capacitance; A first end of the third inductor is used as an input end of the series resonant circuit; the first end of the third capacitor is connected to the third inductor, and the second end of the third capacitor is used as an output end of the series resonant circuit. In a second aspect, the present utility model provides a low noise amplifying circuit comprising a switching unit, a filter, an input matching circuit, a low noise amplifier and an output matching circuit as described above; The first end of the switch unit is used for being connected with an antenna to realize the opening or closing of a channel for receiving signals; An input terminal of the filter is connected to a second terminal of the switching unit; the input end of the input matching circuit is connected to the output end of the filter