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:
Jul. 02, 1991
Filed:
Dec. 26, 1989
Roger R Roth, Minnetonka, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A power control system includes a voltage follower circuit which may be interposed between a load power control circuit which adjusts the level of power applied to a load, and a variable impedance whose internal impedance prescribes the desired level of power. A feedback voltage from the output of the voltage follower circuit is compared with a corresponding voltage across the variable impedance and the difference between them is used to drive the output voltage of the voltage follower circuit toward the input voltage. The voltage follower circuit permits control by a single variable impedance of many more load power control circuits than a single variable impedance can normally handle, and without appreciably affecting the power level as a function of the impedance level. This circuit is particularly useful in a system for controlling the level of light received from fluorescent light fixtures controlled by electronic ballasts.