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. 05, 2012
Filed:
Jun. 30, 2009
David Welland, Austin, TX (US);
David Welland, Austin, TX (US);
Silicon Laboratories Inc., Austin, TX (US);
Abstract
A circuit for determining a value of a variable capacitor includes first circuitry for generating a first indication when a variable voltage across the variable capacitor exceeds a threshold voltage. Second circuitry generates a second indication when a reference voltage across a reference capacitor exceeds the threshold voltage. Control logic responsive to the first and second indications generate a control signal indicating whether the first indication or the second indication occurs first. A successive approximation engine generates an N-bit control value responsive to the control signal. A variable current source is responsive to the N-bit control value for generating a variable current to the first circuitry. A reference current source generates a reference current to the second circuitry.