Method and apparatus for detecting slow and small changes of electrical signals including the sign of the changes, and circuit arrangement for the exact detection of the peak value of an alternating voltage
CA 2379639 C · Owner: Fazakas, Andras · Inventors: Fazakas, Andras
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and electronic circuit for detecting slow and small changes of electrical signal including the sign of the changes, comprising the steps of switching the signal to be detected periodically to a capacitor and changing thereby its charge state taken in the previous period, examining the extent and sign of the decaying current pulse caused when said capacitor has been forced to take the new charge state, if the extent of this decaying current pulse is higher than a predetermined threshold limit storing this , fact and the sign of the change till the next period.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed July 3, 2000 and granted January 4, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 3, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 3, 2022.
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Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.