Granted Patent
Utility
US 5,623,544 · App. 08/062,595
Telephone headset interface circuit
Inventor:
Costas Papadopoulos
Patented Case
View Patent ↗
Granted: Apr 22, 1997
Filed: May 17, 1993
Inventor
Costas Papadopoulos
Assignee (at issue)
VXi 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.