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. 26, 2012
Filed:
Apr. 07, 2006
Machiel Slot, Richmond Hill, CA;
Antonius Jacobus Maria Cremer, Oisterwijk, NL;
Machiel Slot, Richmond Hill, CA;
Antonius Jacobus Maria Cremer, Oisterwijk, NL;
EldoLAB Holding B.V., Eindhoven, NL;
Abstract
The object of the invention is to implement an energy-efficient, compact and cost-effective solution for driving a number of high-power LED groups for lighting applications, by using a single switching power supply together with LEDs connected in series and/or in parallel and pulse width-controlled switches in parallel across the individually controllable LED groups. If the switch of an LED group is ON, the LED group will not light up. If the switch is in the OFF position, the full current of the power supply will pass through the corresponding LED group. Another aspect of the invention is the restriction within the drive protocol, according to which but a single switch is actuated at any one time within a particular time interval. This aspect guarantees a minimum time interval between each individual actuation event. Another aspect is the derating of the power supply in those phases where not a single LED group is ON. In the event of all the switches being closed (all LED groups OFF) the power supply can be derated (or turned off). A further aspect is the use of an elevated current setting of the power supply with the simultaneous restriction of the ON cycle by means of pulse width modulation. The power supply is set to the maximum instantaneous peak current of the LED, while maximum pulse width drive guarantees a maximum of the average LED current, cycle time being left over as a result, thus enabling more LEDs to be driven at a given supply voltage.