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. 09, 1990
Filed:
Aug. 16, 1988
Gerald W Shearer, Orange, CA (US);
Karl M Lofgren, Long Beach, CA (US);
Kenneth W Ouyang, Huntington Beach, CA (US);
Western Digital Corporation, Irvine, CA (US);
Abstract
An integrated circuit chip is fabricated with an operational active device and a nearly-identical, exemplary active device. The exemplary device is connected in series with a current reference element so that current flow through the reference element will be substantially duplicated in the exemplary device. A difference amplifier senses the output voltage of the exemplary device; compares it to a provided reference voltage; and generates a gate biasing level at the gate of the exemplary device to force the output voltage of the exemplary device substantially equal to the reference voltage. The biasing level at the gate of the exemplary device is duplicated at the gate of the operational device thereby creating a condition wherein the output current of the operational device will be a substantially precise replica of the current flow through the reference element when the reference voltage is duplicated across the output of the operational device.