Radio frequency power amplifier based on power detection feedback, chip and communication terminal

Patent metadata

Field	Value
Publication number	US-11323074-B2
Application number	US-201816628243-A
Country	US
Kind code	B2
Filing date	Jun 30, 2018
Priority date	Jul 5, 2017
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Disclosed in the present invention are a radio frequency power amplifier based on power detection feedback, a chip, and a communication terminal. The radio frequency power amplifier comprises multiple stages of amplifier circuits and at least one power detection feedback circuit; the input end of the power detection feedback circuit is connected to the output end of a current stage of amplifier circuit, and the output end of the power detection feedback circuit is connected to the input ends of the current stage of amplifier circuit and at least one stage of amplifier circuit located prior to the current stage of amplifier circuit. The power detection feedback circuit generates, according to the detected output power of the current stage of amplifier circuit, a control voltage varying inversely with the output power, so that the power detection feedback circuit outputs current varying positively with the control voltage.

First claim

What is claimed is:

1. A radio frequency power amplifier based on power detection feedback, comprising multiple stages of amplifier circuits and at least one power detection feedback circuit, wherein an input end of the power detection feedback circuit is connected to an output end of a current stage of amplifier circuit in the multiple stages of amplifier circuits, an output end of the power detection feedback circuit is connected to input ends of the current stage of amplifier circuit and at least one stage of amplifier circuit located prior to the current stage of amplifier circuit; and
the power detection feedback circuit generates, according to the detected output power of the current stage of amplifier circuit, a control voltage varying inversely with the output power, so that the power detection feedback circuit outputs a current varying positively with the control voltage; the current is input into the input ends of the current stage of amplifier circuit and the at least one stage of amplifier circuit located prior to the current stage of amplifier circuit, so that a quiescent operating current of at least one stage of amplifier circuit varies positively with the current; and the radio frequency power amplifier operates in a state in which the gain and the output power are stable.

2. The radio frequency power amplifier based on power detection feedback according to claim 1 , wherein
the radio frequency power amplifier further comprises at least one current detection feedback circuit, wherein an input end of the current detection feedback circuit is connected to an input end of a certain stage of amplifier circuit located posterior to the current stage of amplifier circuit through a corresponding resistor; an output end of the current detection feedback circuit is connected to an input end of at least one stage of amplifier circuit located prior to the current stage of amplifier circuit; and
the current detection feedback circuit generates, according to a detected quiescent operating current of the current stage of amplifier circuit, a control voltage varying inversely with the quiescent operating current, so that the current detection feedback circuit outputs a current varying positively with the control voltage; the current is input into the input end of the at least one stage of amplifier circuit located prior to the current stage of amplifier circuit, so that the quiescent operating current of the at least one stage of amplifier circuit varies positively with the current; and the radio frequency power amplifier operates in a state in which the gain and the output power are stable.

3. The radio frequency power amplifier based on power detection feedback according to claim 1 , wherein
the power detection feedback circuit comprises a first detection circuit and a first feedback circuit, wherein an output end of the first detection circuit is connected to an input end of the first feedback circuit, an input end of the first detection circuit is connected to the output end of the current stage of amplifier circuit, and an output end of the first feedback circuit is connected to the input ends of the current stage of amplifier circuit and the at least one stage of amplifier circuit located prior to the current stage of amplifier circuit.

4. The radio frequency power amplifier based on power detection feedback according to claim 3 , wherein
the input end of the first feedback circuit is connected to an output end of a second detection circuit, and the detected quiescent operating current of the current stage of amplifier circuit is input into the first feedback circuit through the second detection circuit.

5. The radio frequency power amplifier based on power detection feedback according to claim 2 , wherein
the current detection feedback circuit comprises a second detection circuit and a second feedback circuit, wherein an output end of the second detection circuit is connected to an input end of the second feedback circuit, an input end of the second detection circuit is connected to the input end of the current stage of amplifier circuit, and an output end of the second feedback circuit is connected to the input end of the at least one stage of amplifier circuit located prior to the current stage of amplifier circuit.

6. The radio frequency power amplifier based on power detection feedback according to claim 4 , wherein
the first detection circuit is formed by connecting a first resistor and a first capacitor in series, and the second detection circuit consists of a sixth resistor.

7. The radio frequency power amplifier based on power detection feedback according to claim 4 , wherein
the first detection circuit consists of a first capacitor.

8. The radio frequency power amplifier based on power detection feedback according to claim 4 , wherein
each of the first feedback circuit and the second feedback circuit comprises two transistors, a fourth resistor is arranged between a collector of a first transistor and a power supply voltage, a fifth resistor is arranged between the collector of the first transistor and a base of a second transistor, a collector of the second transistor is connected to the power supply voltage, a base of the first transistor is used as the input end of the feedback circuit, and an emitter of the second transistor is used as the output end of the feedback circuit.

9. The radio frequency power amplifier based on power detection feedback according to claim 4 , wherein
when the current detection feedback circuit and the power detection feedback circuit share the first feedback circuit, a bias voltage is respectively provided for the current stage of amplifier circuit and a first transistor through a first bias circuit, the first bias circuit comprises a transistor, a collector of the transistor is connected to the bias voltage, an emitter of the transistor is connected to a base of the first transistor through a sixth resistor, the emitter of the transistor is connected to the input end of the current stage of amplifier circuit, a resistor is arranged between the base of the transistor and the bias voltage, and two diodes are connected in series between the base of the transistor and a ground wire.

10. The radio frequency power amplifier based on power detection feedback according to claim 3 , wherein
a bias voltage is provided for a first transistor of the power detection feedback circuit through a second bias circuit, the second bias circuit comprises a second resistor and a third resistor, one end of the second resistor is connected to a power supply voltage, the other end of the second resistor and one end of the third resistor are connected together to form the output end of the second bias circuit, and the other end of the third resistor is grounded.

11. The radio frequency power amplifier based on power detection feedback according to claim 5 , wherein
a bias voltage is respectively provided for a first transistor of the current detection feedback circuit and the current stage of amplifier circuit through a first bias circuit.

12. The radio frequency power amplifier based on power detection feedback according to claim 1 , wherein
in the multiple stages of amplifier circuits, each stage of amplifier circuit is a common emitter amplifier circuit consisting of a bipolar transistor or a CMOS transistor, a load is arranged between each stage of amplifier circuit and a power supply voltage, the load is a resistor or an inductor, and a capacitor is arranged between an input end of a posterior stage of amplifier circuit and an output end of a prior stage of amplifier circuit.

13. A chip, comprising the radio frequency power

Assignees

• Vanchip Tianjin Tech Co Ltd

Inventors

• Zhao Jinxin
• Bai Yunfang

Classifications

• H03F1/26

  Modifications of amplifiers to reduce influence of noise generated by amplifying elements · CPC title

• H03G3/3042

  in modulators, frequency-changers, transmitters or power amplifiers · CPC title

• H03F1/34 Primary

  Negative-feedback-circuit arrangements with or without positive feedback (H03F1/02 - H03F1/30, H03F1/38 - H03F1/50, H03F3/50 take precedence {; for rejection of common mode signals H03F3/45479}) · CPC title

• H03F3/245 Primary

  with semiconductor devices only · CPC title

• H03F3/24

  of transmitter output stages · CPC title