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. 04, 1997
Filed:
Aug. 01, 1995
Edward P Coleman, Jr, Fairport, NY (US);
PSC Inc., Webster, NY (US);
Abstract
A resolution enhancer circuit provides an increased resolution capability for an A/D converter. The resolution enhancer circuit receives as input an analog input signal having a range greater than the effective range of the A/D, and prescales the input signal to a range that is within the common mode range of op amps used within the resolution enhancer circuit. The input signal can also have a range much less than the effective range of the A/D, and then it would be increased by the prescaler to be within an operable range of the A/D. The prescaled signal is provided to a sampling circuit, which samples the prescaled signal at times determined to be near-saturation conditions of the A/D. A magnified difference between the prescaled signal and the sampled signal, biased to the sampled signal, is then input to the A/D, which determines a number of A/D counts based on that value. As the input signal varies, the number of A/D counts may approach either a high or low saturation condition, which causes a resampling of the prescaled signal. This resampling of the prescaled signal effectively moves the approximate center of a high resolution window to a current value of the analog input signal, and allows for an n-bit A/D to provide increased resolution for a wide ranging analog input signal.