RF PA linearity requirements based converter operating mode selection

• US 8,942,650 B2
• Filed: 11/03/2011
• Issued: 01/27/2015
• Est. Priority Date: 04/20/2010
• Status: Active Grant

• Current Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Original Assignee: RF Micro Devices Incorporated (Qorvo, Inc.)
• Inventors: Southcombe, William David, Levesque, Chris, Arkiszewski, Roman Zbigniew, Jones, David E., Yoder, Scott, Stockert, Terry J.
• Primary Examiner(s): LE, NHAN T
• Application Number:
  US13/288,517
• Publication Number:
  US 20120282869A1
• Time in Patent Office: 1,181 Days
• Field of Search: 4551271-1275, 455/129, 4553431-3436
• US Class Current: 455/127.1
• CPC Class Codes: H03F 1/0227 using supply converters
• CPC Class Codes: H03F 1/0261 with control of the polarisation voltage or current, e.g. gliding Class A
• CPC Class Codes: H03F 1/0277 Selecting one or more amplifiers from a plurality of amplifiers
• CPC Class Codes: H03F 2200/171 A filter circuit coupled to the output of an amplifier
• CPC Class Codes: H03F 2200/222 A circuit being added at the input of an amplifier to adapt the input impedance of the amplifier
• CPC Class Codes: H03F 2200/27 A biasing circuit node being switched in an amplifier circuit
• CPC Class Codes: H03F 2200/318 A matching circuit being used as coupling element between two amplifying stages
• CPC Class Codes: H03F 2200/336 A I/Q, i.e. phase quadrature, modulator or demodulator being used in an amplifying circuit
• CPC Class Codes: H03F 2200/387 A circuit being added at the output of an amplifier to adapt the output impedance of the amplifier
• CPC Class Codes: H03F 2200/411 the output amplifying stage of an amplifier comprising two power stages
• CPC Class Codes: H03F 2200/414 A switch being coupled in the output circuit of an amplifier to switch the output on/off
• CPC Class Codes: H03F 2200/417 A switch coupled in the output circuit of an amplifier being controlled by a circuit
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2200/504 the supply voltage or current being continuously controlled by a controlling signal, e.g. the controlling signal of a transistor implemented as variable resistor in a supply path for, an IC-block showed amplifier
• CPC Class Codes: H03F 2200/534 Transformer coupled at the input of an amplifier
• CPC Class Codes: H03F 2200/537 A transformer being used as coupling element between two amplifying stages
• CPC Class Codes: H03F 2200/541 Transformer coupled at the output of an amplifier
• CPC Class Codes: H03F 2203/21106 An input signal being distributed in parallel over the inputs of a plurality of power amplifiers
• CPC Class Codes: H03F 2203/21142 Output signals of a plurality of power amplifiers are parallel combined to a common output
• CPC Class Codes: H03F 2203/21157 A filter circuit being added at the output of a power amplifier stage
• CPC Class Codes: H03F 3/195 : in integrated circuits
• CPC Class Codes: H03F 3/211 : using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/245 : with semiconductor devices only
• CPC Class Codes: H03F 3/602 : Combinations of several amplifiers
• CPC Class Codes: H03F 3/72 : Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal

Abstract

A power amplifier (PA) envelope power supply, radio frequency (RF) PA circuitry, and a process to select a converter operating mode of the PA envelope power supply based on linearity requirements of the RF PA circuitry is disclosed. The PA envelope power supply operates in one of a first converter operating mode and a second converter operating mode. The process for selecting the converter operating mode is based on a required degree of linearity of the RF PA circuitry. The PA envelope power supply provides an envelope power supply signal to the RF PA circuitry. Selection of the converter operating mode may provide efficient operation of the PA envelope power supply and the envelope power supply signal needed for proper operation of the RF PA circuitry.

Claims

1. A method comprising:

identifying a required degree of linearity of radio frequency (RF) power amplifier (PA) circuitry; and

selecting one of a first converter operating mode and a second converter operating mode of a PA envelope power supply based on the required degree of linearity wherein;

in the first converter operating mode, an envelope power supply signal is supplied to the RF PA circuitry via a charge pump buck converter in the PA envelope power supply, and a buck converter in the PA envelope power supply is inactive; and

in the second converter operating mode, the envelope power supply signal is supplied to the RF PA circuitry via the buck converter, and the charge pump buck converter is inactive.

2. The method of claim 1 further comprising using the envelope power supply signal to provide RF transmit signals.

3. The method of claim 1 wherein the PA envelope power supply has a higher efficiency during the second converter operating mode than during the first converter operating mode.

4. The method of claim 1 wherein the RF PA circuitry provides higher degrees of linearity with higher magnitudes of the envelope power supply signal.

5. The method of claim 4 wherein the envelope power supply signal is higher during the first converter operating mode than during the second converter operating mode.

6. Circuitry comprising:

radio frequency (RF) power amplifier (PA) circuitry;

a PA envelope power supply; and

control circuitry adapted to;

identify a required degree of linearity of the RF PA circuitry; and

select one of a first converter operating mode and a second converter operating mode of the PA envelope power supply based on the required degree of linearity wherein;

in the first converter operating mode, an envelope power supply signal is supplied to the RF PA circuitry via a charge pump buck converter in the PA envelope power supply, and a buck converter in the PA envelope power supply is inactive; and

in the second converter operating mode, the envelope power supply signal is supplied to the RF PA circuitry via the buck converter, and the charge pump buck converter is inactive.

7. The circuitry of claim 6 wherein the RF PA circuitry is adapted to use the envelope power supply signal to provide RF transmit signals.

8. The circuitry of claim 6 wherein the PA envelope power supply is adapted to have a higher efficiency during the second converter operating mode than during the first converter operating mode.

9. The circuitry of claim 6 wherein the RF PA circuitry comprises:

a first RF PA comprising;

a first non-quadrature PA path having a first single-ended output; and

a first quadrature PA path coupled between the first non-quadrature PA path and an antenna port, such that the first quadrature PA path has a first single-ended input, which is coupled to the first single-ended output; and

a second RF PA comprising a second quadrature PA path coupled to the antenna port,

wherein the antenna port is configured to be coupled to an antenna.

10. The circuitry of claim 6 wherein the RF PA circuitry comprises:

a first multi-mode multi-band quadrature RF PA coupled to multi-mode multi-band alpha switching circuitry via a single alpha PA output; and

the multi-mode multi-band alpha switching circuitry having;

a first alpha non-linear mode output associated with a first non-linear mode RF communications band; and

a plurality of alpha linear mode outputs, such that each of the plurality of alpha linear mode outputs is associated with a corresponding one of a first plurality of linear mode RF communications bands.

11. The circuitry of claim 6 wherein the RF PA circuitry comprises:

a first RF PA comprising a first final stage having a first final bias input, such that bias of the first final stage is via the first final bias input;

PA control circuitry;

a PA-digital communications interface (DCI) coupled between a digital communications bus and the PA control circuitry; and

a final stage current digital-to-analog converter (IDAC) coupled between the PA control circuitry and the first final bias input.

12. The circuitry of claim 6 further comprising a direct current (DC)-DC converter adapted to receive a DC power supply signal from a DC power supply and provide a bias power supply signal based on the DC power supply signal, such that a voltage of the bias power supply signal is greater than a voltage of the DC power supply signal, such the RF PA circuitry comprises:

a first RF PA having a first final stage and adapted to;

receive and amplify a first RF input signal to provide a first RF output signal; and

receive a first final bias signal to bias the first final stage;

PA bias circuitry adapted to receive the bias power supply signal and provide the first final bias signal based on the bias power supply signal.

13. The circuitry of claim 6 further comprising a direct current (DC)-DC converter comprising:

the PA envelope power supply comprising the charge pump buck converter coupled to the RF PA circuitry; and

a PA bias power supply comprising a charge pump coupled to the RF PA circuitry.

14. The circuitry of claim 6 wherein the RF PA circuitry comprises:

multi-mode multi-band RF power amplification circuitry having at least a first RF input and a plurality of RF outputs, such that;

configuration of the multi-mode multi-band RF power amplification circuitry associates one of the at least the first RF input with one of the plurality of RF outputs; and

the configuration is associated with at least a first look-up table (LUT);

PA control circuitry coupled between the multi-mode multi-band RF power amplification circuitry and a PA-digital communications interface (DCI), such that the PA control circuitry has at least the first LUT, which is associated with at least a first defined parameter set; and

the PA-DCI, which is coupled to a digital communications bus.

15. The circuitry of claim 6 wherein the RF PA circuitry is adapted to provide higher degrees of linearity with the higher magnitudes of the envelope power supply signal.

16. The circuitry of claim 15 wherein the envelope power supply signal is higher during the first converter operating mode than during the second converter operating mode.