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. 19, 2004
Filed:
Mar. 16, 2001
Aaron Grant Simmons, San Jose, CA (US);
Robert Eric Fesler, Saratoga, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
Voltage regulators use capacitors to compensate the voltage regulator and provide stable performance. Capacitors have an inherent equivalent series resistance (ESR) that changes over various operating conditions including signal frequency, operating temperature as well as others. An apparatus and method compensates for the low ESR of capacitors to increase the total equivalent series resistance of the capacitor. By providing an “on-chip” resistance between the capacitor and the circuit ground potential, minimum total ESR can be provided such that stable load regulation is achieved with capacitors that would otherwise be undesirable for such use. Increasing the value of the output capacitor's equivalent series resistance allows wider ranging values of capacitance to be used. The increased range of capacitance values allows capacitors of different material types to be used. Additionally, other arrangements with multiple resistors that are arranged as series resistors between the compensation capacitor and one or more of the power supplies provide stable load regulation.