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, 1988
Filed:
Mar. 21, 1986
Timothy L Blankenship, Palm Bay, FL (US);
Joseph G Nolan, III, San Jose, CA (US);
Harris Corporation, Melbourne, FL (US);
Abstract
A test enabling circuit for actuating specific testing circuitry contained within a programmable device, whereby the test enabling circuit and a portion of the normal operational circuits of the device share a common input pin. Because of the dual functionality of the common input pin, the test enabling circuit is designed to respond to a specified test signal, which is either of an opposing polarity, or of a higher magnitude of the same polarity with respect to the normal operational signal. The enabling circuit includes several IGFET devices arranged such that the noise margin of the enabling circuit may be adapted for accommodating varying environments of noise. ESD circuitry is included to protect the testing and test enabling circuits against electrostatic discharge.