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:
Dec. 31, 2002
Filed:
Mar. 01, 2001
Michael Muth, Stelle, DE;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
In an evaluation circuit for evaluating an output signal of a magnetoresistive sensor ( ) for rotational speed measurement, in which the evaluation circuit performs an offset compensation of the sensor signal and comprises a comparator ( ) which receives the offset compensated sensor signal and compares it with a reference voltage, a reliable identification of the output signal of the sensor after switching on the arrangement is ensured in that, in an initial mode, the value of the reference voltage is selected in dependence upon the temperature, the temperature dependence being approximated to that of the sensor signal, in that a control unit ( ) is provided which, in the initial mode, consecutively checks whether the sensor signal is present, triggers the offset compensation only after the presence of said signal, subsequently checks whether the comparator ( ) supplies an output signal, and changes over to a control mode only after the presence of said signal, in which control mode the temperature dependence of the reference voltage is switched off and, instead, the reference voltage is adjusted to approximately 40% of the maximum amplitude of the offset-compensated sensor signal.