Circuit for energizing cold-cathode fluorescent lamps
CA 2272674 A1 · Owner: O2 Micro International Ltd. · Inventors: Lin, Yung; Chou, John; Liu, Kwang H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An electrical circuit for simultaneously energizing at least a pair of CCFLs that are connected in series. The circuit also includes a transformer having a primary winding adapted to receive an alternating current. A secondary winding is coupled in series with the CCFLs to energize their operation. A shunt capacitor, connected in parallel across one CCFL significantly reduces the peak voltage that must be applied across the CCFLs. Usually the circuit also includes an isolation capacitor connected in series between the CCFLs and the secondary winding of the transformer. The isolation capacitor provides both DC blocking and electrical isolation between the secondary winding and the CCFLs.
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 25, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 25, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 25, 2021.
- 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.