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:
Dec. 01, 2009
Filed:
Mar. 22, 2006
Eric Naviasky, Ellicott City, MD (US);
Michelle Williams, Laurel, MD (US);
Eric Naviasky, Ellicott City, MD (US);
Michelle Williams, Laurel, MD (US);
Cadence Design Systems, Inc., San Jose, CA (US);
Abstract
A frequency-to-current converter includes a digitally selectable capacitor, a sampling capacitor, an integrator circuit and an output transconductor. The sampling capacitor is operatively coupled via a first switch to the digitally selectable capacitor. The first switch is operated by a first clock pulse from a clock generator responsive to a reference clock. The integrator circuit has an output operatively coupled via a second switch to the sampling capacitor. The integrator circuit has an output operatively coupled to a control terminal of the transistor. The second switch is operated by a second, non-overlapping clock pulse from the clock generator. A current output by the frequency-to-current converter in response to the continuous question of first and second switches is linearly proportional to the frequency of the reference clock and the capacitance of the digitally selectable capacitor.