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. 09, 2010
Filed:
May. 01, 2008
Mahesh K Madhavan, Kerala, IN;
Srikanth Aruna Nittala, East Godavari Dt., IN;
Mahesh K Madhavan, Kerala, IN;
Srikanth Aruna Nittala, East Godavari Dt., IN;
Analog Devices, Inc., Norwood, MA (US);
Abstract
An SAR ADC provides increased immunity to noise introduced by time varying noise components provided on reference potentials (V). Reference voltage noise contributions are canceled by introducing a reference voltage component to a pair of binary weighted capacitor arrays (NDAC and PDAC) during bit trials, which are presented to a differential comparator as a common mode signal and rejected. During sampling, select elements in either the PDAC or the NDAC also obtain a reference voltage contribution. Although the sampled Vsignal may have a noise contribution, the noise is fixed at the time of bit trials, which can improve performance. Generally, the scheme provides a 50% reduction in noise errors over the prior art for the same Vnoise. Additional embodiments described herein can reduce noise errors to 25% or even 12.5% over prior art systems.