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. 27, 2001
Filed:
Nov. 18, 1998
Applicant:
Inventor:
Ke-Chiang Huang, Hsinchu, TW;
Assignee:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03D 1/06 ; H03D 7/14 ;
U.S. Cl.
CPC ...
H03D 1/06 ; H03D 7/14 ;
Abstract
A DC offset cancellation circuit comprises a subtracter, a noise shaper, an accumulator and an attenuator. The subtracter is used to subtract a quantized DC offset from a digital signal. The noise shaper converts an unquantized DC offset into the quantized DC offset, the quantized DC offset having fewer bits than the unquantized DC offset and an average value in the time domain that is approximately equal to the unquantized DC offset. The accumulator generates an accumulation value by means of summing the outputs of the subtracter. The attenuator is employed to multiply the accumulation value by a constant, which is less than one, and transmit the resulting initial DC offset to the subtracter.