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. 29, 1999
Filed:
Sep. 29, 1997
Applicant:
Inventors:
Jeremy C Smith, Austin, TX (US);
Stephen G Jamison, Buda, TX (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02H / ; H01L / ;
U.S. Cl.
CPC ...
326 30 ; 361 56 ;
Abstract
An electrostatic discharge (ESD) circuit (700) provides robust protection to an input/output driver circuit (10). The discharge path is provided by a bipolar transistor (202). The bipolar device is triggered by a combination of an n-type MOSFET (702), a string of diodes (200), and a biasing circuit (704). The trigger point of the MOSFET is programmable by varying the number of individual diodes in the string of diodes. The relatively high transconductance of the n-type MOSFET allows the use of a smaller ESD circuit for a given degree of protection.