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:
Sep. 14, 2021
Filed:
Feb. 18, 2020
Omnivision Technologies, Inc., Santa Clara, CA (US);
Zhiyong Zhan, Fremont, CA (US);
Tongtong Yu, Fremont, CA (US);
Xin Wang, Cupertino, CA (US);
Liang Zuo, San Mateo, CA (US);
Kenny Geng, Mountain View, CA (US);
OmniVision Technologies, Inc., Santa Clara, CA (US);
Abstract
A test voltage sample and hold circuitry is disclosed in a readout circuitry of an image sensor. This circuitry samples a voltage at demand value based on a ramp voltage shared by the ADC comparators of the readout circuitry. The value of the sampled voltage is controlled by a control circuitry which is able to predict and calculate at what time a ramp generator may carry the demand voltage value. The sampled voltage is held by a hold capacitor during readout of one row and is accessed during the next row by the control circuitry as test data to drive a device under test (DUT) which may be any portion of the image sensor to be tested. Measured data out of the DUT is compared with expected data. Based on the result of the comparison, a signal indicates the pass or fail of the self-test concludes a self-test of the DUT.