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:
Nov. 28, 1995
Filed:
Aug. 24, 1994
Kwok-Fu Chiu, San Jose, CA (US);
Don R Sauer, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
An improved input protection circuit receiving a differential signal has a small signal input circuit and a large signal input circuit. The small signal input circuit is active when the differential input signal has a magnitude not exceeding a predetermined value. The large signal input circuit is active when the differential input signal has a magnitude exceeding the predetermined value. Because the small signal input circuit does not see a large differential signal across the gate terminals of its input transistors, offset voltage ('V.sub.os ') drift is avoided resulting in enhanced circuit reliability. A switch circuit isolates the small signal input circuit when the large signal input circuit is active.