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. 11, 2011
Filed:
Sep. 04, 2008
Franz Prexl, Oberding, DE;
Erich-johann Bayer, Thonhausen, DE;
Juergen Neuhaeusler, Bad Aibling, DE;
Franz Prexl, Oberding, DE;
Erich-Johann Bayer, Thonhausen, DE;
Juergen Neuhaeusler, Bad Aibling, DE;
Texas Instruments Deutschland GmbH, Freising, DE;
Abstract
An electronic device includes circuitry for driving a light-emitting diode (LED) or other light-emitting semiconductor device. The circuitry includes a first switch (NM) coupled with the light-emitting semiconductor device (LED) for switching a current (I) through the light-emitting semiconductor device (LED); a sensing means (R) for sensing a magnitude of the current (I) and outputting a respective sensing signal (SEN); an error amplifier (AMP) for receiving the sensing signal (SEN) and a target value (ISET) for the current (I) for providing a first control voltage (VG) based on the deviation of the actually sensed current magnitude and the current target value (ISET); a lowpass filter coupled to the error amplifier (AMP) for filtering the first control voltage (VG) and providing a second control voltage (VG); a voltage follower (NM) coupled to the lowpass filter and the first switch for receiving the second control voltage (VG) and providing a third control voltage (VG) for controlling the first switch's (NM) switching activity; and a second switch (PM, NM) for switching a supply current (IDS) of the voltage follower (NM) for switching the voltage follower (NM) on and off.