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:
May. 30, 1995
Filed:
Jan. 12, 1994
Takeshi Kajimoto, Tokyo, JP;
Mitsuteru Kobayashi, Saitama, JP;
Katsuyuki Sato, Tokyo, JP;
Yutaka Shimbo, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In LSI circuit devices having a plurality of subchips packaged therein and having specific functions, capacitance cutting buffer circuits are employed in conjunction with respective terminals of the subchips, and a driver is disposed at respective points where relatively long wiring lines are respectively sub-divided into a corresponding plurality of lines. As a result, signal transmission delay can be significantly reduced. The terminals of the subchips are also provided with a probing pad to test the operations of the subchips independently of one another. The subchips employ circuit blocks which are to operate simultaneously and in conjunction with the wirings of the subchips, power supply lines are disposed correspondingly to the distributively arranged circuit blocks. Bus lines also controllably transmit addresses as well as data signals in a time sharing manner. Furthermore, each of the subchips has a fault test circuit. The subchips which have a DC fault is electrically isolated thereby allowing the remainder of the subchip to be usable. In the fault relieving technique employed, a combination of memory locations wherein no fault exists is selected for use, thereby allowing the construction of an LSI even with subchips which correspond to faulty bit addresses. The fault relieving technique employed uses an address converting circuit for faulty addresses, this operation being performed automatically within the chip system.