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:
May. 20, 2008
Filed:
Sep. 21, 2005
Stefan Groiss, Villach-Landskron, AT;
Stefan Groiss, Villach-Landskron, AT;
Infineon Technologies AG, Munich, DE;
Abstract
A log circuit receives an operated current signal and a reference current signal at respective inputs and comprises an operand log circuit including a first bipolar semiconductor device and being configured to generate a first logarithmized signal on the basis of the operand current signal, a reference log circuit including a second bipolar semiconductor device and being configured to generate a second logarithmized signal on the basis of the reference current signal, and a differential-amplifier circuit receiving the first logarithmized signal and the second logarithmized signal, and outputting a differential-amplifier output signal in dependency on the first logarithmized signal and the second logarithmized signal. The differential amplifier is configured such that its amplification depends on a thermal voltage of a bipolar semiconductor device, so that at the output signal of the differential amplifier, the temperature dependency of the difference between the first logarithmized signal and the second logarithmized signal is counteracted.