Patent Yard Sign in
Expired European patentEurope

Rfi suppression technique for switching circuits

EP 0243403 B1 · Applicant: AT&T Corp.

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed September 29, 1986 and granted June 6, 1990. A European patent lasts at most 20 years from filing, so its term ended September 29, 2006.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by March 29, 2012.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledSeptember 29, 1986
PublishedNovember 4, 1987
GrantedJune 6, 1990
Term endedSeptember 29, 2006
Application numberEP 86906193
Classification (CPC)H02M1/44 +1 more

Timeline

Timeline From EPO dates

1987198919911993199519971999200120032005Application filedSep 29, 1986PublishedNov 4, 1987Patent grantedJune 6, 1990Term endedSep 29, 2006

Sources & verification