US 10,892,719 B2
Multistage power amplifier with linearity compensating function
Kyu Jin Choi, Suwon-si (KR); and Je Hee Cho, Suwon-si (KR)
Assigned to Samsung Electro-Mechanics Co., Ltd., Suwon-si (KR)
Filed by SAMSUNG ELECTRO-MECHANICS CO., LTD., Suwon-si (KR)
Filed on Feb. 25, 2019, as Appl. No. 16/284,599.
Claims priority of application No. 10-2018-0078186 (KR), filed on Jul. 5, 2018.
Prior Publication US 2020/0014343 A1, Jan. 9, 2020
Int. Cl. H03F 3/04 (2006.01); H03F 3/21 (2006.01); H03F 1/02 (2006.01); H03F 3/19 (2006.01); H03F 1/30 (2006.01)
CPC H03F 3/211 (2013.01) [H03F 1/0211 (2013.01); H03F 1/302 (2013.01); H03F 3/04 (2013.01); H03F 3/19 (2013.01); H03F 2200/102 (2013.01); H03F 2200/451 (2013.01); H03F 2203/21131 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A multistage power amplifier comprising:
a first amplification circuit configured to receive a first bias current;
a second amplification circuit configured to receive a second bias current;
an envelope detection circuit configured to output a direct current (DC) detection voltage based on an envelope of an input radio frequency (RF) signal; and
a bias compensation circuit configured to compensate for the first bias current based on the second bias current in a high-power driving region in response to the DC detection voltage.