US 12,231,099 B2
Composite cascode power amplifiers for envelope tracking applications
Aleksey A. Lyalin, Moorpark, CA (US); Huiming Xu, Newbury Park, CA (US); Shayan Farahvash, Kensington, CA (US); and Reinhard Ulrich Mahnkopf, Oberhaching (DE)
Assigned to Skyworks Solutions, Inc., Irvine, CA (US)
Filed by Skyworks Solutions, Inc., Irvine, CA (US)
Filed on Nov. 14, 2023, as Appl. No. 18/509,060.
Application 18/509,060 is a continuation of application No. 17/302,952, filed on May 17, 2021, granted, now 11,855,595.
Claims priority of provisional application 62/704,977, filed on Jun. 5, 2020.
Prior Publication US 2024/0088849 A1, Mar. 14, 2024
Int. Cl. H04B 1/38 (2015.01); H03F 1/02 (2006.01); H03F 3/24 (2006.01)
CPC H03F 3/245 (2013.01) [H03F 1/0233 (2013.01); H04B 1/38 (2013.01); H03F 2200/105 (2013.01); H03F 2200/451 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A mobile device comprising:
a transceiver configured to generate a radio frequency signal;
a power management system including an envelope tracker configured to generate a power amplifier supply voltage based on an envelope of the radio frequency signal; and
a front end system including a composite cascode power amplifier configured to amplify the radio frequency signal and to receive power from the power amplifier supply voltage, the composite cascode power amplifier including an enhancement mode field-effect transistor having a gate configured to receive the radio frequency signal, and a depletion mode field-effect transistor having a source connected to a drain of the enhancement-mode field-effect transistor, the envelope tracker including a DC-to-DC converter configured to output a plurality of regulated voltages, a modulator configured to generate a modulator output voltage at an output based on the plurality of regulated voltages and the envelope of the radio frequency signal, and a modulator output filter coupled between the output of the modulator and the power amplifier supply voltage.