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:
Dec. 11, 2018
Filed:
May. 25, 2016
Philips Lighting Holding B.v., Eindhoven, NL;
PHILIPS LIGHTING HOLDING B.V., Eindhoven, NL;
Abstract
An LED driver uses a switch mode power supply either to provide a regulated LED current (in a first mode) that connects directly to the LED arrangement or a regulated LED voltage (in a second mode) to an LED output terminal. An auxiliary power supply is either based on an auxiliary secondary side (i.e. an auxiliary secondary side winding) when in the first mode, or it is based on the regulated LED voltage when in the second mode. The LED driver further comprises an input adapted to receive a standby command for the driver, wherein the main controlling unit is adapted to control the driver in the second mode when receiving the standby command for the driver. In this way, the driver has a single shared stage which can operated in a regulated current (i.e. constant current) mode to drive the LED arrangement directly or a regulated voltage (i.e. constant voltage) mode. It can adaptively change between modes to improve the standby power efficiency. When the load is turned on (e.g. a first mode), the driver may function in constant current mode, and when the load is turned off (e.g. a second, standby mode), the driver works in constant voltage mode with the output voltage stepped down so that not sufficient to turn on the LED arrangement to be driven by the driver but enough to provide auxiliary power via the auxiliary power supply, in order to improve the auxiliary power efficiency.