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:
Aug. 17, 2004
Filed:
Jul. 30, 2002
Clifford I. Drowley, Scottsdale, AZ (US);
Shrinath Ramaswami, Gilbert, AZ (US);
FreeScale Semiconductor, Inc., Austin, TX (US);
Abstract
An extended dynamic range pixel cell providing blooming protection is disclosed herein. By applying a timed varying signal to a shunt transistor in order to shunt excess charge generated by a photosensor in response to high intensity illumination, blooming protection can be provided. In particular configurations, blooming protection is provided not only during an integration period but also during a readout period when the pixel cell is generally most susceptible to blooming problems. The time varying voltage is also used to extend the dynamic range of the pixel cell thereby increasing the pixel cells usefulness in high contrast conditions, such as bright sunlight casting deep shadows, nighttime automotive applications, and the like.