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. 07, 2011
Filed:
Jul. 13, 2007
William C. Moyer, Dripping Springs, TX (US);
Kelly K. Taylor, Austin, TX (US);
William C. Moyer, Dripping Springs, TX (US);
Kelly K. Taylor, Austin, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A circuit and method provides an estimate of a population count (popcount) of a plurality of input bit values. In one form the input bit values represent respective nodes of an integrated circuit. An approximation circuit uses an approximation input stage which receives a plurality of data inputs and has a plurality of logic circuits. Each logic circuit provides a single bit output. The approximation circuit provides monotonic accuracy. A reduction tree receives the single bit outputs of the plurality of logic circuits and provides an approximate count of how many of the plurality of data inputs are asserted. Size and speed are improved by providing the estimate as opposed to an exact value.