Logarithmic amplification circuit
CA 2062010 C · Owner: Nec Electronics Corporation · Inventors: Kimura, Katsuji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A logarithmic amplification circuit is provided which comprises a differential amplifier, a full-wave rectifier including two half-wave rectifiers connected so as to have their input signals reverse in phase to each other and respectively receiving an input signal and output signal of said differential amplifier, and an adder for adding the output signals of said full-wave rectifier. It is preferable that each of the half-wave rectifiers forming said full-wave rectifier includes a differential transistor pair only one transistor of which has an emitter resistor. In this case two sets of differential transistor pair of said two halfwave rectifiers are arranged so that the transistors each …
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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 February 27, 1992 and granted April 22, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 27, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 27, 2014.
- 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.