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:
Oct. 03, 2017
Filed:
May. 13, 2016
Allegro Microsystems, Llc, Worcester, MA (US);
Nai-Chi Lee, Nashua, NH (US);
Vijay Mangtani, Nashua, NH (US);
Allegro Microsystems, LLC, Worcester, MA (US);
Abstract
An LED driver for driving a plurality of series-coupled LEDs includes a bypass switch having first and second terminals coupled across a portion of the LEDs and a control terminal. A slew rate control circuit is responsive to a command input signal and to a feedback voltage associated with the bypass switch and is configured to generate a bypass switch control signal with a controllable slew rate. The slew rate control circuit is further configured to detect a rate of change of the switch feedback voltage and establish the bypass switch slew rate in response to the detected rate of change. Also described is method for controlling a bypass switch coupled across a portion of a plurality of series-coupled LEDs including detecting a rate of change of a voltage associated with the bypass switch and generating a control signal for the bypass switch in response to a command input signal and to the detected rate of change of the voltage.