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:
Sep. 03, 2002
Filed:
Oct. 02, 2000
Anthony Stratakos, Fremont, CA (US);
Andrew J. Burstein, Mountain View, CA (US);
David B. Lidsky, Oakland, CA (US);
Phong Nguyen, Pleasanton, CA (US);
William Clark, Fremont, CA (US);
Volterra Semiconductor Corporation, Fremont, CA (US);
Abstract
A sensor for measuring a current passing through a load. The sensor has a power transistor having a first terminal connected to substantially constant voltage and a second terminal connected to the load. The sensor can sample a voltage difference with a variable capacitor, and a controller can be configured to cause a variable capacitor in the current sensor to have a capacitance inversely proportional to a resistance of the power transistor, whereby a charge stored on the variable capacitor is proportional to the current passing through the power transistor when the sampling switches are opened. A comparator can compare the current through the power transistor to a known reference current to generate a digital output signal. The sensor can include a power transistor, reference transistor and amplifier connected and configured so as to generate a signal on a reference line having a current of known proportion to the current passing through the load.