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:
Oct. 29, 1996
Filed:
Sep. 21, 1994
Masao Noro, Hamamatsu, JP;
Takayuki Kohdaka, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
An analog-to-digital converter mainly comprises an analog-to-digital conversion unit which produces a digital output, as an equivalent of an analog input supplied thereto, by performing a successive approximation. Herein, an instantaneous value of the analog input is compared with a reference signal so as to determine the digit in each of the bits of the digital output. The analog-to-digital converter can further comprise an analog comparator, an analog amplifier and a digital attenuator in order to reduce an effect of the noise. The analog amplifier amplifies the analog input by a gain so as to produce an intermediate analog signal. The analog-to-digital conversion unit converts the intermediate analog signal into an intermediate digital signal. The digital attenuator attenuates the intermediate digital signal by an attenuation rate so as to produce the digital output. The attenuation rate is determined such that a product, obtained by multiplying the gain and attenuation rate together, is normally equal to a value `1`. The analog comparator evaluates the level of the analog input by comparing it with predetermined levels in turn. Thus, the analog comparator controls the gain of the analog amplifier in accordance with a result of the evaluation.