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:
Nov. 09, 1999
Filed:
Feb. 03, 1998
Majid Naveed, Mohegan Lake, NY (US);
Edwin Kluter, Nijmegen, NL;
Erwin Seinen, Malden, NL;
Robert J Fronen, Nijmegen, NL;
Ton Mobers, Grave, NL;
Philips Electronics North America Corporation, New York, NY (US);
Abstract
In a switched-mode power supply, when the controller and the switching device are encapsulated together with a heat sink, in which the drain of the switching device is connected to the heat sink, the heat sink and the paths to the various pins of the controller forms various parasitic capacitances which, when the switching device switches, injects and withdraws inordinately large currents into and from the pins of the controller. In the case of the V.sub.CTRL pin to which is connected a discharge capacitor, the resulting under voltage across the capacitor may be used by circuitry connected to the V.sub.CTRL pin to control the switching of the switching device resulting in throwing the switched-mode power supply out of regulation. A track-and-hold circuit is now connected between the V.sub.CTRL pin and the circuitry to mirror the voltage across the discharge capacitor. During the times when current would be withdrawn from the discharge capacitor due to capacitance coupling, the track-and-hold circuit isolates the circuitry from the resulting under voltage.