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. 28, 1989
Filed:
Sep. 28, 1987
Takeji Tokumaru, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In a carry adder of Manchester type, a carry is generated for each full adder and transmitted from a less significant bit to a more significant bit via a series-connected pass transistors. To increase the carry transmission speed, a carry skip circuit is usually connected across pass transistors classified as a block. However, since the skip circuit is still connected to turn-on resistances and stray capacitances of the pass transistors, the carry transmission speed is low and unstable. To overcome this problem, the skip circuit is selectively disconnected from the pass transistors, in response to a NAND signal indicative of the absence of carry signals of the full adder in the same block, by means of two mate clocked inverters alternatively activated by two opposite-level clocks .phi. and .phi..