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. 02, 1990
Filed:
Jul. 11, 1989
Shoichi Watanabe, Takasaki, JP;
Takayuki Takei, Takasaki, JP;
Terumine Hayashi, Hitachi, JP;
Takashi Natabe, Ibaragi, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Microcomputer Engineering Ltd., Tokyo, JP;
Abstract
A method is provided for manufacturing a master slice semiconductor integrated circuit device. Initially, a first total circuit diagram which is to be reformed into a master slice semiconductor integrated circuit device is defined. First and second circuit points on the first total circuit block which are to be used respectively as input and output terminals of the master slice semiconductor integrated circuit device are specified. Next, signal transmitting paths are successively traced from the output to the input of each logic gate located in the signal transmitting paths in actual use. In the course of the tracing, these traced gates are marked and the logic gates actually in use are identified. As a result, in addition to those logic gates having unused output terminals, the gates constituting a closed loop isolated from the signal transmitting paths for transmitting substantial output signals are identified as unnecessary gates and deleted. Further, gates outputting only a fixed value are determined and designated unnecessary gates which are also deleted.