Low frequency discriminator circuit
CA 2123847 C · Owner: Casselman, Patrick H. · Inventors: Casselman, Patrick H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a low frequency discriminator circuit comprised if apparatus for providing a rectangular wave input signal apparatus, for integrating the input signal apparatus for, detecting whether the integrated input signal falls between upper and lower thresholds respectively and, apparatus for providing an output signal indicating when the integrated input signal falls between the thresholds, whereby the frequency of the input signal may be determined to be between higher and lower limits.
Read the whole patent
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 May 18, 1994 and granted November 11, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 18, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 18, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.