The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 12, 2022
Filed:
Feb. 28, 2021
Shenzhen Goodix Technology Co., Ltd., Shenzhen, CN;
Mohamed Elsayed, San Diego, CA (US);
Matthew Powell, San Diego, CA (US);
Xiaodong Wang, San Diego, CA (US);
Shenzhen Goodix Technology Co., Ltd., Shenzhen, CN;
Abstract
Techniques are described for implementing reduced-noise pixel ramp voltage generators for image sensors. The described pixel ramp voltage generators include circuit blocks to address various conventional causes of ramp generator noise. For example, a reference current is generated. Current steering can be used to toggle between a ramp-run mode for generation of a ramp voltage, and a ramp-stop mode for stopping the generation, thereby mitigating changes in low-frequency noise components between pixel conversion cycles, or phases or such cycles. Buffer multiplier techniques can be used to isolate kickback noise of the pixel conversion comparators from components generating the ramp voltage, such as to mitigate image smearing. Some implementations include additional features, such as sample-and-hold techniques used to isolate ramp generation components from current generation component noise, slope calibration techniques to dynamically tune voltage ramp slope, reset techniques, etc.