US 11,924,569 B2
Image sensor sampling pixel signal multiple times and an operating method of the image sensor
Yunhong Kim, Seoul (KR); Heesung Chae, Seoul (KR); Yunhwan Jung, Hwaseong-si (KR); and Haesick Sul, Hwaseong-si (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by Samsung Electronics Co., Ltd., Suwon-si (KR)
Filed on May 25, 2022, as Appl. No. 17/824,607.
Claims priority of application No. 10-2021-0091686 (KR), filed on Jul. 13, 2021.
Prior Publication US 2023/0016998 A1, Jan. 19, 2023
Int. Cl. H04N 25/75 (2023.01); H04N 25/701 (2023.01); H04N 25/772 (2023.01)
CPC H04N 25/75 (2023.01) [H04N 25/701 (2023.01); H04N 25/772 (2023.01)] 19 Claims
OG exemplary drawing
 
1. An image sensor for sampling a pixel signal a plurality of times during a readout time, the image sensor comprising:
an analog comparator configured to compare a signal level of the pixel signal with a signal level of a target ramp signal that is any one of a plurality of ramp signals;
a counter configured to output counting data based on a comparison result of the analog comparator;
a digital comparing circuit configured to compare a binary value of a target reference code corresponding to the target ramp signal with a binary value of the counting data and determine whether to output a digital signal corresponding to the counting data to a data output circuit based on a result of the comparison between the binary value of the counting data and the binary value of the target reference code; and
a ramp signal generator configured to generate the plurality of ramp signals during the readout time and transmit the plurality of ramp signals to the analog comparator,
wherein the plurality of ramp signals are a plurality of successive ramp signals, and each of the plurality of ramp signals has a maximum signal level that is less than a maximum signal level of a previous ramp signal generated previously during the readout time.