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. 23, 2010
Filed:
Jun. 03, 2008
Applicant:
James Garrett, Nashua, NH (US);
Inventor:
James Garrett, Nashua, NH (US);
Assignee:
Fairchild Semiconductor Corporation, South Portland, ME (US);
Primary Examiner:
Int. Cl.
CPC ...
H03K 5/08 (2006.01);
U.S. Cl.
CPC ...
Abstract
The present invention includes a pass transistor that limits current drawn from a circuit without using a series resistor and while drawing minimal current from an external supply. A current mirror of the output current is formed and compared to a reference current. When the output current increases, the mirror current increases proportionally, and when a threshold is crossed, the pass transistor is turned off. The pass transistor is biased from a charge pump that provides a voltage, a current from which a current mirror is drawn that controls the pass transistor.