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:
Feb. 18, 1992
Filed:
Apr. 20, 1990
Thomas M Luich, Campbell, CA (US);
National Semiconductor Corp., Santa Clara, CA (US);
Abstract
An output buffer circuit advantageously uses a simple integrated circuit package including two separate ground leads for connection to an externally supplied ground voltage. The relatively large pull down current which passes through the pull down transistor of one or more output buffers are fed through a first ground lead of the lead frame to the external ground and the remaining circuitry is connected to the external ground through the second ground lead of the lead frame. The transients in the pull down current will cause ground bounce which affects the pull down transistor only, and not the remaining components of the output buffer. In this manner, base drive to the output pull down transistor is not decreased due to ground bounce, and the high to low transition of the output voltage is not degraded by the presence of ground bounce. In an alternative embodiment, the amount of ground bounce is controlled to provide a desired characteristic of the output transition.