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:
Jul. 28, 1992
Filed:
Mar. 19, 1991
Nobuyuki Yasutake, Tokyo, JP;
Hidefumi Yabara, Yokohama, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A D/A converter converting a digital signal having n bits (n is an integer) into an analog signal includes constant-current output circuits, provided for the n bits of the digital signal, for selectively generating n constant currents on the basis of the n bits of the digital signals. The n constant currents have mutually different current values with respect to the n bits of the digital signal. The constant-current output circuits have resistance elements respectively provided for the n bits of the digital signal. The resistance elements define the mutually different current values. The D/A converter also includes an output circuit for adding the n constant currents to each other and for outputting the analog signal based on an addition result, and a temperature-dependent voltage generating part for generating a temperature-dependent voltage which changes as a temperature around the D/A converter changes. Further, the D/A converter includes a current compensation part for generating a compensation voltage related to at least one of the resistance elements from the temperature-dependent voltage and for applying the compensation voltage to the one of the resistance elements. The compensation voltage compensates for a temperature-dependent variation in a characteristic of the one of the resistance elements.