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:
Jun. 30, 2009
Filed:
Jan. 22, 2007
Kok Keong Richard Lum, Singapore, SG;
Kah Weng Lee, Singapore, SG;
Bin Zhang, Singapore, SG;
Avago Technologies ECBU IP (Singapore) Pte. Ltd., Singapore, SG;
Abstract
A light sensor having first and second photodetectors and a current mirror is disclosed. The first photodetector receives a light signal and generates a light current proportional to the light intensity received by the first photodetector and a dark current that is independent of the light intensity. The second photodetector is connected in series with the first photodetector at a first node. The second photodetector has a covering that prevents light from reaching the second photodetector. The second photodetector generates a current equal to the dark current. The first photodetector is connected to a power source and the second photodetector is connected to an output node. The current mirror is connected to the first node and the output node and generates an output current that is proportional to the light current through the output node when the output node is connected to an external circuit.