US 12,218,639 B2
Interface circuit including variable impedance circuit and operating method thereof
Jiyeon Park, Suwon-si (KR); and Kihwan Seong, Hwaseong-si (KR)
Assigned to Samsung Electronics Co., Ltd., (KR)
Filed by Samsung Electronics Co., Ltd., Suwon-si (KR)
Filed on Jan. 31, 2022, as Appl. No. 17/588,617.
Claims priority of application No. 10-2021-0029082 (KR), filed on Mar. 4, 2021.
Prior Publication US 2022/0286095 A1, Sep. 8, 2022
Int. Cl. H03F 1/56 (2006.01); H03F 3/45 (2006.01)
CPC H03F 1/56 (2013.01) [H03F 3/45179 (2013.01); H03F 2203/45576 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An interface circuit comprising:
a first amplifier circuit comprising a first input terminal configured to receive a first input signal, a second input terminal configured to receive a second input signal, a first output node configured to output a first output signal, a second output node configured to output a second output signal, and a variable impedance circuit comprising a first impedance circuit connected to the first output node, and a second impedance circuit connected to the second output node; and
a code generator circuit configured to generate a first control code and a second control code, wherein the first impedance circuit is configured to adjust an impedance thereof based on the first control code, and the second impedance circuit is configured to adjust an impedance thereof based on the second control code,
wherein the first input signal is a voltage signal provided from an external device through a receiver pin, and the second input signal is a reference voltage signal having a predetermined voltage level.