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:
Feb. 17, 2004
Filed:
Oct. 30, 2002
Shinsuke Ohnishi, Tokyo, JP;
Daisuke Takagi, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
Digital-to-analog (DA) conversion circuitry with a simplified testing circuit includes a DA converter to which test data, initially “0”, may be applied. The DA converter feeds an analog voltage corresponding to the test data to a voltage holding circuit. Subsequently the test data is incremented to “1” and then converted to a corresponding analog voltage by the DA converter. A comparator compares the analog voltage corresponding to the test data “1” with the previous analog voltage held in the voltage holding circuit and corresponding to the test data “0”. When the test data is sequentially incremented by 1 (one) at intervals, the voltage output from the DA converter is higher than the voltage held in the voltage holding circuit while the DA converter operates normally. The function of the DA converter can be easily, rapidly tested by monitoring the output of the comparator.