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:
Nov. 23, 2004
Filed:
Dec. 27, 2002
STMicroelectronics S.r.l., Agrate Brianza, IT;
Abstract
A method for calibrating a frequency of a sigma—delta modulator having a go path that includes, in series, a resonator circuit and of an analog to digital conversion block, and a feedback path including a digital to analog conversion block, including the steps: a) applying an input pulse to the resonator circuit; b) measuring the oscillating frequency of the output signal from the resonator circuit in response to the pulse, while the feedback path of the sigma—delta modulator is opened; c) comparing the oscillating frequency of the resonator circuit with a selected frequency; d) modifying the oscillating frequency proportionately as a function of the comparison step. The resonator circuit includes an integrator filter with a variable gain amplifier in its feedback path, the variable gain configured to be modified as a function of the comparison, performed while the modulator feedback path is opened.