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. 06, 1987
Filed:
Apr. 10, 1986
Zeev Barzilai, Millwood, NY (US);
Vijay S Iyengar, Peekskill, NY (US);
Gabriel M Silberman, Haifa, IL;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A shift register latch (SRL) arrangement for testing a combinational logic circuit, producing true and complement outputs in nature, has two clocked DC latches and additional circuitry for providing an input to the second latch. Clock signal trains and an extra TEST signal are used to control the SRL arrangement in different modes. In a first mode, one of the outputs from the combinational logic circuit is latched into the first latch and provided to a succeeding combinational logic circuit. In a second mode, a plurality of the SRL arrangements are interconnected together to form a shift register chain so that each latch acts as one position of the shift register chain. Further, in a third mode, the true and complement outputs of the combinational logic circuit are exclusive ORed and its result is latched into the second latch. During the third mode, output of the first latch is prevented from being latched into the second latch.