Multi-mode power amplifiers with phase matching

Abstract

Apparatus and methods for multi-mode power amplifiers are provided herein. In certain configurations, a wireless device includes a multi-mode power amplifier including a plurality of amplification paths electrically connected in parallel with one another. The plurality of amplification paths includes a first amplification path including an input stage of a first stage type and an output stage of a second stage type, and a second amplification path including an output stage of the second stage type. The first stage type provides non-inverting gain and the second stage type provides inverting gain. The wireless device further includes a transceiver that provides a radio frequency signal to the multi-mode power amplifier, and that operates the multi-mode power amplifier in a selected power mode chosen from a plurality of power modes based on selectively activating one or more of the plurality of amplification paths.

1 . (canceled) 
     
     
         2 . A multi-mode power amplifier comprising:
 a first input stage and a first output stage in a first amplification path, the first input stage of a first type providing non-inverting gain and the first output stage of a second type providing inverting gain;   a second input stage and a second output stage in a second amplification path, the second input stage of the first type and the second output stage of the second type;   an input switch and a third output stage in a third amplification path that is in parallel with the first amplification path and the second amplification path, the third output stage of the second type; and   a bias circuit configured to operate the multi-mode power amplifier in a selected power mode chosen from a plurality of power modes, the bias circuit configured to selectively activate the first amplification path by controlling a bias of the first input stage, and to selectively activate the second amplification path by controlling a bias of the second input stage.   
     
     
         3 . The multi-mode power amplifier of  claim 2  wherein the third amplification path is selectively activated by a mode control signal to the input switch. 
     
     
         4 . The multi-mode power amplifier of  claim 2  wherein a fewer number of stages are present in the third amplification path relative to each of the first amplification path and the second amplification path. 
     
     
         5 . The multi-mode power amplifier of  claim 2  wherein the multi-mode power amplifier is switchable amongst the plurality of power modes without phase discontinuity. 
     
     
         6 . The multi-mode power amplifier of  claim 2  wherein the first type is a common-base amplifier stage and the second type is a common-emitter amplifier stage. 
     
     
         7 . The multi-mode power amplifier of  claim 2  wherein the first type is a common-gate amplifier stage and the second type is a common-source amplifier stage. 
     
     
         8 . The multi-mode power amplifier of  claim 2  wherein the plurality of power modes include a first power mode in which the first amplification path is activated and the second amplification path is deactivated, and a second power mode in which the first amplification path is deactivated and the second amplification path is activated. 
     
     
         9 . The multi-mode power amplifier of  claim 2  wherein the bias circuit is configured to bias the first input stage and the second input stage as a multi-throw switch. 
     
     
         10 . A wireless device comprising:
 a transceiver configured to output a radio frequency signal; and   a multi-mode power amplifier configured to amplify the radio frequency signal, the multi-mode power amplifier including a first input stage of a first type and a first output stage of a second type in a first amplification path, a second input stage of the first type and a second output stage of the second type in a second amplification path, an input switch and a third output stage of the second type in a third amplification path that is in parallel with the first amplification path and the second amplification path, and a bias circuit configured to operate the multi-mode power amplifier in a selected power mode chosen from a plurality of power modes, the first type providing non-inverting gain and the second type providing inverting gain, the bias circuit configured to selectively activate the first amplification path by controlling a bias of the first input stage, and to selectively activate the second amplification path by controlling a bias of the second input stage.   
     
     
         11 . The wireless device of  claim 10  wherein the third amplification path is selectively activated by a mode control signal to the input switch. 
     
     
         12 . The wireless device of  claim 10  wherein a fewer number of stages are present in the third amplification path relative to each of the first amplification path and the second amplification path. 
     
     
         13 . The wireless device of  claim 10  wherein the multi-mode power amplifier is switchable amongst the plurality of power modes without phase discontinuity. 
     
     
         14 . The wireless device of  claim 10  wherein the first type is a common-base amplifier stage and the second type is a common-emitter amplifier stage. 
     
     
         15 . The wireless device of  claim 10  wherein the first type is a common-gate amplifier stage and the second type is a common-source amplifier stage. 
     
     
         16 . The wireless device of  claim 10  wherein the plurality of power modes include a first power mode in which the first amplification path is activated and the second amplification path is deactivated, and a second power mode in which the first amplification path is deactivated and the second amplification path is activated. 
     
     
         17 . The wireless device of  claim 10  wherein the bias circuit is configured to bias the first input stage and the second input stage as a multi-throw switch. 
     
     
         18 . The wireless device of  claim 10  further comprising an antenna configured to transmit an amplified radio frequency signal provided by the multi-mode power amplifier. 
     
     
         19 . A method of radio frequency amplification, the method comprising:
 amplifying a signal using a first amplification path in a first power mode of a multi-mode power amplifier, the first amplification path including a first input stage of a first type providing non-inverting gain and a first output stage of a second type providing inverting gain;   amplifying the signal using a second amplification path in a second power mode of the multi-mode power amplifier, the second amplification path including a second input stage of the first type and a second output stage of the second type;   amplifying the signal using a third amplification path in a third power mode of the multi-mode power amplifier, the third amplification path in parallel with the first amplification path and the second amplification path and including an input switch and a third output stage of the second type; and   biasing the multi-mode power amplifier using a bias circuit, including selectively activating the first amplification path in the first power mode by controlling a bias of the first input stage, and selectively activating the second amplification path in the second power mode by controlling a bias of the second input stage using the bias circuit.   
     
     
         20 . The method of  claim 19  further comprising switching amongst the first power mode, the second power mode, and the third power mode without phase discontinuity. 
     
     
         21 . The method of  claim 19  further comprising selectively activating the third amplification path in the third power mode using a mode control signal to the input switch.