Granted Patent
Utility
US 5,132,890 · App. 07/639,493
Power supply based on normally parasitic resistance of solid state switch
Inventor:
Tom Blandino
Patented Case
View Patent ↗
Granted: Jul 21, 1992
Filed: Jan 9, 1991
Inventor
Tom Blandino
Assignee (at issue)
Koss Corporation
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.