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:
Nov. 12, 1985
Filed:
Apr. 02, 1984
Robert S Wrathall, Tempe, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A current sensing circuit is disclosed wherein a small portion of a load current is sampled through a sensing resistor and a substantially larger portion of the load current is allowed to bypass the sensing resistor. A first high current vertical MOS transistor is coupled between the load and the ground terminal. A second vertical MOS transistor is coupled in series between the load and ground terminal. The transistors are constructed in a vertical MOS cellular construction whereby the first transistor comprises on the order of three-thousand cells and the second transistor comprises a single cell. A signal is taken across the sensing resistor and may be provided as feedback to a control means driving the first and second transistors for performing a current limiting or constant current function.