Power amplifier

Patent metadata

Field	Value
Publication number	US-9899962-B2
Application number	US-201715432990-A
Country	US
Kind code	B2
Filing date	Feb 15, 2017
Priority date	Jul 10, 2014
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

er amplifier includes a power splitter that splits a first signal into a second signal and a third signal delayed from the second signal by about 90°, a first amplifier that outputs a fourth signal by amplifying the second signal when a power level of the first signal equals/exceeds a first level, a second amplifier that outputs a fifth signal by amplifying the third signal when the power level of the first signal equals/exceeds a second level higher than the first level, a first phase shifter that receives the fourth signal and outputs a sixth signal delayed from the fourth signal by about 45°, a second phase shifter that receives the fifth signal and outputs a seventh signal advanced from the fifth signal by about 45°, and a combining unit that outputs an amplified signal of the first signal by combining the sixth and seventh signals.

First claim

What is claimed is:

1. A power amplifier comprising:
a power splitter that splits a first signal into a second signal and a third signal delayed from the second signal by about 90 degrees;
a first amplifier that outputs a fourth signal by amplifying the second signal when a power level of the first signal equals or exceeds a first level;
a second amplifier that outputs a fifth signal by amplifying the third signal when the power level of the first signal equals or exceeds a second level higher than the first level;
a first phase shifter that receives an input of the fourth signal and outputs a sixth signal delayed from the fourth signal by about 45 degrees;
a second phase shifter that receives an input of the fifth signal and outputs a seventh signal advanced from the fifth signal by about 45 degrees; and
a combining unit that outputs an amplified signal of the first signal by combining the sixth signal and the seventh signal,
wherein the first phase shifter comprises a first inductor and a second capacitor, the first inductor having an inductance equal to R L /ω and the second capacitor having a capacitance equal to 1/(2R L ω),
wherein R L is an impedance on a load side of the power amplifier as viewed from the combining unit, and ω is an angular frequency corresponding to a center frequency of an input signal to the power amplifier.

2. The power amplifier according to claim 1 , wherein the first inductor is connected in series between the first amplifier and the combining unit, and
wherein the second phase shifter comprises a first capacitor connected in series between the second amplifier and the combining unit.

3. The power amplifier according to claim 2 , wherein the second capacitor has one end electrically connected to the combining unit and another end grounded, and
wherein the second phase shifter further comprises a second inductor having one end electrically connected to the combining unit and another end grounded.

4. The power amplifier according to claim 1 , wherein the power splitter includes a coupled-line 3 dB coupler.

5. The power amplifier according to claim 1 , further comprising a third amplifier that outputs the first signal by amplifying the input signal.

6. The power amplifier according to claim 5 , further comprising a switch that connects the first signal to the power splitter or the combining unit based on a power mode signal that controls output power.

7. The power amplifier according to claim 2 , wherein the power splitter includes a coupled-line 3 dB coupler.

8. The power amplifier according to claim 3 , wherein the power splitter includes a coupled-line 3 dB coupler.

9. The power amplifier according to claim 2 , further comprising a third amplifier that outputs the first signal by amplifying the input signal.

10. The power amplifier according to claim 3 , further comprising a third amplifier that outputs the first signal by amplifying the input signal.

11. The power amplifier according to claim 4 , further comprising a third amplifier that outputs the first signal by amplifying the input signal.

12. The power amplifier according to claim 9 , further comprising a switch that connects the first signal to the power splitter or the combining unit based on a power mode signal that controls output power.

13. The power amplifier according to claim 10 , further comprising a switch that connects the first signal to the power splitter or the combining unit based on a power mode signal that controls output power.

14. The power amplifier according to claim 11 , further comprising a switch that connects the first signal to the power splitter or the combining unit based on a power mode signal that controls output power.

15. The power amplifier according to claim 1 , wherein the power splitter, the first amplifier, the second amplifier, the first phase shifter, the second phase shifter, and the combining unit are provided on a single IC chip.

Assignees

• Murata Manufacturing Co

Inventors

• Takenaka Kiichiro

Classifications

• H03F3/72

  Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal · CPC title

• H03F2203/21172

  A series resonance circuit being coupled at the output of a power amplifier · CPC title

• H03F3/211

  using a combination of several amplifiers (H03F3/60 takes precedence) · CPC title

• H03F1/0277

  Selecting one or more amplifiers from a plurality of amplifiers · CPC title

• H03F3/195

  in integrated circuits · CPC title