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. 16, 2003
Filed:
Aug. 03, 2001
Chin Chang, Yorktown Heights, NY (US);
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
An integrated LED driving device for multiple LED strings which employs a single linear regulator or other controller and a multiple-output current mirror which is almost independent of the DC input voltage source, almost independent of the transistor's or MOSFET's variations from the semiconductor integration process, and almost independent of temperature variation. The multiple-output current mirror includes a plurality of transistors or MOSFETs each of which are integrated on the same substrate, with identical width-to-length channel ratios and with identical source and gate connections. The integrated LED driving device provides for automatic current sharing in a DC mode and, alternately, with minimized phase delays in a PWM mode. The mirror-output current mirror may include mirror-cascode transistor pairs.