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:
Apr. 19, 2011
Filed:
Apr. 02, 2007
Hee Wong, San Jose, CA (US);
Hee Wong, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
Proportional, integral and derivative error gains within a proportional-integral-derivative filter are selected based on a magnitude of the error value and with successively higher gain values corresponding to larger ranges of error values. Coding of the error gains is selected based on one or more of: large code-dynamic-range to achieve good transient and quiescent responses; small code-step ratio to achieve smooth transitions between consecutive steps; large gain control range to satisfy the differing gain coverage requirements of the three proportional, integral and derivative error; positive and negative code symmetry with small step increment about zero; reservation of code space for dead band elimination; allocation of code space to prevent overflow/underflow during multiplying and bit-shifting; and minimum cost and power.