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:
Nov. 18, 1997
Filed:
Sep. 21, 1995
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A digital-analog converter has unit current source cells each having a differential switch circuit and a constant current source. The differential switch circuit made of two switches is driven by a pair of complementary driving circuits controlled by a bit signal and the inverted bit signal corresponding to that signal and entered simultaneously. The constant current source outputs a constant current to a first and a second current output terminal via the switch circuit. The signals for controlling the driving circuits that drive the switches are such that the delay time for the switch closing operation will be longer than the delay time for the switch opening operation. As a result, the cross point of the two signals to open and close the switches in a complementary manner becomes greater than the median between the maximum and minimum signal levels. That is, even when the threshold value of a currently switching transistor is greater than a median, that value may be arranged to match the median, whereby the furnished switching transistors are not turned on or off simultaneously.