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:
Jun. 05, 2018
Filed:
Jun. 21, 2016
Shigeru Uekusa, Kanagawa, JP;
Shigeru Uekusa, Kanagawa, JP;
RICOH COMPANY, LTD., Tokyo, JP;
Abstract
A self-test circuit is driven by a multiphase clock signal which includes N number of clock signals in same cycle having phases from first to N-th phases each phase-shifted by 1/N of the cycle. The self-test circuit includes a data selecting circuit, a serialization circuit, and a logical test circuit. The data selecting circuit switches input data that are input as M-bit wide parallel data to the self-test circuit, between normal data and test data for logical test. The serialization circuit performs serial conversion of the input data in N-parallel manner and outputs bits in N-parallel manner, as a single serial output signal at timing corresponding to each phase. In synchronization with timing corresponding to each phase, the logical test circuit imports the serial output signal as N-parallel bit strings each having length equal to M/N number of bits and performs a bit logical test for M number of bits.