Granted Patent
Utility
US 4,369,491 · App. 06/147,285
Protective circuitry for transistorized d-c/d-c converter
Inventor:
Luigi Rizzi
Patented Case
View Patent ↗
Granted: Jan 18, 1983
Filed: May 6, 1980
Inventor
Luigi Rizzi
Assignee (at issue)
Societa Italiana Telecomunicazioni Siemens S.p.A.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.