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:
Jan. 26, 1993
Filed:
Mar. 03, 1992
Applicant:
Inventor:
Michael E Wright, Berkeley, CA (US);
Assignee:
National Semiconductor Corp., Santa Clara, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B60T / ; H03K / ;
U.S. Cl.
CPC ...
307 43 ; 3072961 ; 3072993 ; 307243 ; 307529 ; 328156 ; 328158 ; 323315 ;
Abstract
A novel circuit is taught to provide a smooth current transfer function over a range of two input voltages, so that power can be supplied to an electronic circuit from more than a single power source. In one embodiment such power sources include a battery and an DC supply operated off the AC mains. Associated with each such supply is a current source designed to provide a reference current. This reference current is used to establish mirror currents from each of the power leads in order to provide the desired output current.