US 12,149,216 B2
System and method for adjusting amplifier bias using envelope tracking
Ali Fard, Corona Del Mar, CA (US); and Mats Carlsson, Sundbyberg (SE)
Assigned to QuantalRF AG, (CH)
Filed by QuantalRF AG, Zurich (CH)
Filed on May 3, 2022, as Appl. No. 17/735,358.
Application 17/735,358 is a continuation in part of application No. 17/668,298, filed on Feb. 9, 2022.
Claims priority of provisional application 63/147,668, filed on Feb. 9, 2021.
Prior Publication US 2022/0337205 A1, Oct. 20, 2022
Int. Cl. H03F 1/34 (2006.01); H03F 1/02 (2006.01); H03F 3/195 (2006.01); H03F 3/24 (2006.01)
CPC H03F 3/245 (2013.01) [H03F 1/0222 (2013.01); H03F 3/195 (2013.01); H03F 2200/102 (2013.01); H03F 2200/451 (2013.01); H03F 2200/537 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method, comprising:
receiving an input signal;
providing, by an amplifier circuit, an output signal in response to the input signal wherein the output signal has an envelope and wherein the amplifier circuit includes an amplifier and a transformer, the transformer being configured to establish a magnetically coupled feedback loop from an output of the amplifier to an input of the amplifier wherein the transformer includes a primary winding connected to the output of the amplifier and a secondary winding connected to the input of the amplifier;
detecting the envelope of the output signal at the output of the amplifier and generating an envelope detection signal corresponding to the envelope of the output signal;
adjusting a bias current, and not a supply voltage, provided to the amplifier circuit based upon the envelope detection signal.