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:
Feb. 19, 1991
Filed:
Sep. 22, 1988
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
In a circuit for testing integrated circuit devices, scan registers (8.about.16) and data selecting circuits (20-28) are connected between a plurality of circuit blocks (29.about.31) in correspondence with the number of bits of the data, with the scan registers connected to each other by a shift register path so as to have a function of one shift register as a whole. A register selecting circuit (20.about.28) is connected to a clock input terminal (T1, T2) of the scan register. The scan registers other than those corresponding to the logic circuit block to be tested are selected by the register selecting circuit. Consequently, clocks for scanning scan registers other than those provided before and after the required circuit block are eliminated, enabling reduction of time required for scan test.