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:
Mar. 02, 1993
Filed:
Jan. 09, 1992
Applicant:
Inventors:
Assignees:
Nokia Matkapuhelimet Oy, Salo, FI;
Fincitec Oy, Kemi, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03M / ;
U.S. Cl.
CPC ...
341131 ; 341143 ;
Abstract
The invention relates to a digital sigma-delta modulator for a D/A converter, comprising an integration stage or several cascaded integration stages and a feedback circuit for feedbacking the sign of the output signal of the last integration stage, delayed by one clock cycle and multiplied by a predetermined scaling coefficient, to each integration stage. To avoid limit cycle oscillation, the state of at least the least significant free bit in at least one integration stage is variable at random.