US 11,876,494 B2
Protection circuit of power amplifier and power amplifier including the same
Gyu-Suck Kim, Suwon-si (KR); Youngsik Hur, Suwon-si (KR); and Geunyong Lee, 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 Apr. 29, 2021, as Appl. No. 17/243,906.
Claims priority of application No. 10-2020-0186673 (KR), filed on Dec. 29, 2020.
Prior Publication US 2022/0209728 A1, Jun. 30, 2022
Int. Cl. H03F 1/30 (2006.01); H03F 3/24 (2006.01); H03F 1/52 (2006.01); H03F 3/195 (2006.01)
CPC H03F 3/245 (2013.01) [H03F 1/302 (2013.01); H03F 1/52 (2013.01); H03F 3/195 (2013.01); H03F 2200/318 (2013.01); H03F 2200/451 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A protection circuit, configured to protect a power amplifier comprising a power transistor configured to receive a power supply voltage, and a bias circuit configured to supply a bias current to the power transistor, the protection circuit comprising:
a first transistor, connected between a terminal of the bias circuit and a ground, and configured to sink a first current from the terminal of the bias circuit; and
a second transistor, comprising a first terminal connected to the power supply voltage, a second terminal connected to a control terminal of the first transistor, and a control terminal connected to a reference voltage,
wherein a voltage corresponding to the power supply voltage is output at the second terminal of second transistor.