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. 22, 1994
Filed:
Jun. 17, 1992
Matthias Gruetzner, Stuttgart, DE;
Leendert M Huisman, Peekskill, NY (US);
Sandip Kundu, Mohegan Lake, NY (US);
Cordt W Starke, Weil Der Stadt, DE;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A test pattern generator includes a random pattern generator and a shift register. The random pattern generator generates a series of digits which are input to the shift register and stored therein. Each digit output by the random pattern generator has a probability of having a first value, such as representing '1'. The output probability of the random pattern generator is adjustable. The shift register has a plurality of outputs for outputting a test pattern comprising the stored digits. The shift register includes a series of latches and at least a first logic circuit connecting the output of the random pattern generator to the input of a first latch, or connecting the output of a latch to the input of a next adjacent latch. In a first state, the logic circuit has an output probability which is independent of the output probability of the random pattern generator. In a second state, the logic circuit has an output probability which is dependent on the output probability of the random pattern generator.