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:
Sep. 17, 1996
Filed:
Apr. 14, 1995
Tetsuo Kato, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
In a dynamic random access memory device, first, second and third switches and an internal signal generator therefor are provided besides circuit portions of an ordinary random access memory such as a memory cell. A data input circuit includes data input pins for receiving an input data and data-in-buffers for storing the input data. The first switch can connect one of data input pins to either one of data in buffers or an end of a signal line. The second switch can connect the data-in-buffers to a data output circuit. The third switch can connect the internal voltage supply line to either an internal voltage generator or the other end of the signal line. When a memory is tested, the switch signal generator generates signals so as to make the first switch connect the one of said input pins to the end of the signal line, to make the second switch to connect the data in buffer to the data output circuit, and to make the third switch to connect an internal voltage supply line to the other end of the signal line. Thus, an external voltage can be supplied through one of the data input pins instead of an internal voltage generator, and defective products can be selected out. In an alternative example, the first switch is provided for the data output pins instead of the data input pins.