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:
May. 17, 2005
Filed:
Dec. 17, 2002
John P. Fairbanks, Roseville, CA (US);
John P. Fairbanks, Roseville, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
The present invention can be employed with any power supply circuit where it is desirable to employ a ratio adaptive, gated oscillator based step up switching regulator with a selectable duty cycle. By selecting a particular value for a capacitor coupled between the regulator's Frequency and Switch pins, a user can optimize the regulator's duty cycle for a particular application. Also, by adding a resistor in series with the capacitor, a time constant is created that limits the total charge transfer from taking place at high frequencies more than it does at low frequencies. Additionally, by selecting particular values for the capacitor and resistor, the user can adjust the duty cycle for an application as a function of the battery voltage and output voltage.