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:
Sep. 02, 2014
Filed:
Sep. 16, 2010
Hans Björklund, Ludvika, SE;
Krister Nyberg, Smedjebacken, SE;
Tommy Segerbäck, Ludvika, SE;
ABB Technology AG, Zürich, CH;
Abstract
A device for sensing a binary signal includes a device configured to measure a signal level of the signal, a device configured to determine whether the measured signal level is 'low' or 'high', a device configured to provide a variable input impedance, and a device configured to control the input impedance in response to the measured signal level. The variable input impedance may be provided by way of a transistor and a resistor, and by controlling the duty ratio of the transistor using pulse width modulation. Preferably, the input impedance is controlled to be low for low signal levels and to be high for high signal levels, which results in a more reliable sensing of binary signals. The device may be used for detecting the state of contact transducers suffering from parasitic resistances caused by moist and/or polluted environments. Further, a method of sensing a binary signal is provided.