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:
Jun. 24, 2003
Filed:
May. 01, 2002
Matthijs D. Pardoen, Sunnyvale, CA (US);
Integration Associates Inc., Mountain View, CA (US);
Abstract
One aspect of the present invention detects an equivalent series resistance (ESR) of an external capacitor and adjusts a transfer function of a feedback loop of the voltage regulator to compensate for the ESR. The ESR is detected by measuring a phase shift in a ripple voltage signal of an output voltage of the voltage regulator. Based upon the measured phase shift, an adjustable capacitance is introduced to the feedback loop to compensate for the ESR by introducing a zero to the transfer function to stabilize the voltage regulator circuit. Another aspect of the present invention is to adjust the transfer function of the feedback loop to improve transient response. By measuring both the phase shift and the amplitude of the ripple voltage signal, a gain and the position of a pole in the transfer function of the feedback loop may be adjusted to improve the transient response.