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:
Jul. 05, 2016
Filed:
Aug. 07, 2013
Pixart Imaging Inc., Hsin-Chu, TW;
Wooi Kip Lim, Penang, MY;
PIXART IMAGING INC., Hsin-Chu, TW;
Abstract
A bipolar junction transistor (BJT) pixel circuit, an image sensor and a driving method thereof are provided. The BJT pixel circuit includes a BJT, a photodetector, a feedback amplifier circuit, a shutter circuit, and a current generating unit. The photodetector generates a first base current to a base of the BJT responsive to a light incident on the photodetector. The feedback amplifier circuit is operative to increase an emitter voltage of the BJT according to the light intensity. The shutter circuit controls an exposure time of the photodetector according to a shutter signal. The current generating unit generates the second pulsed base current responsive to a trigger signal causing a base voltage of the BJT to drop while the feedback amplifier circuit operates to increase the emitter voltage of the BJT so as to build-up the base-emitter voltage to a predetermined voltage level when a light source turns on.