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:
Apr. 17, 2012
Filed:
Nov. 24, 2008
Hio Leong Chao, Tucson, AZ (US);
A. Paul Brokaw, Tucson, AZ (US);
Hio Leong Chao, Tucson, AZ (US);
A. Paul Brokaw, Tucson, AZ (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
A voltage regulator comprises first and second bipolar transistors operating at different current densities; a resistance is connected between their bases across which ΔVappears. A third bipolar transistor is connected such that its base voltage is equal to that of the first transistor or differs by a PTAT amount. A current mirror balances the collector current of one of the second and third transistors with an image of the collector current of the first transistor when an output node is at a unique operating point. The operating point includes both PTAT and CTAT components, the ratio of which can be established to provide a desired temperature characteristic. A feedback transistor provides current to the bases of the bipolar transistors and to the output node and is driven by the current mirror output to regulate the voltage at the output node by negative feedback.