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. 22, 1998
Filed:
Dec. 09, 1996
Robert W Jebens, Skillman, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
A high efficiency resonant impedance transforming network for driving a high efficiency infrared LED and the associated method for decreasing the rise time and fall time of the LED to enable the LED to operate at higher frequencies than would ordinarily be possible. The resonant impedance transforming network includes an inductively coupled circuit that contains a primary winding and a secondary winding. The LED and at least one capacitor are coupled in parallel to the secondary winding of the transformer. The secondary winding charges the capacitors connected to it. During the rise time of the LED, the charge stored in the capacitors is discharged to the LED. The discharged charge supplements the current supplied by the secondary winding and the LED experiences a current spike during its rise time that significantly shortens the duration of the rise time. As the LED is conducting a space charge is contained within the LED. During the fall time of the LED, the space charge is actively recovered and stored, thereby significantly reducing the duration of the fall time and improving efficiency.