Granted Patent
Utility
US 4,558,185 · App. 06/445,976
Subscriber line interface circuit with complex impedance
Inventors:
Yuichi Morikawa, Kazuo Saito, Eiichi Amada, Hirotoshi Shirasu
Patented Case
View Patent ↗
Granted: Dec 10, 1985
Filed: Dec 1, 1982
Inventors
Yuichi Morikawa
Kazuo Saito
Eiichi Amada
Hirotoshi Shirasu
Assignees (at issue)
Nippon Telegraph and Telephone Public Corporation
HITACHI, LTD.
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.