The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 11, 2001
Filed:
Feb. 08, 2000
Tsutomu Yamada, Hitachi, JP;
Kenichi Kurosawa, Hitachi, JP;
Yasuo Kaminaga, Hitachi, JP;
Kouji Masui, Hitachi, JP;
Akihiro Ohashi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
There is provided an input/output device having of not exerting any adverse influence on other expansion devices connected to a system bus at the time of insertion or removal. An expansion device,comprises an electronic circuit,and a MOS switch,and is connected to a system bus (BUS) via a connector having long and short pins. The expansion device,two power supply systems, namely a stable power supply,and an unstable power supply,At the time of insertion or removal of the expansion device,power is provided to the MOS switch,and a high impedance maintaining circuit from the stable power supply via a pair of long pins, so as to reliably place the MOS switch,in a high impedance state, inside the expansion device the high impedance maintaining circuit,drives an open/close control terminal, and power is provided to the electronic circuit,from the unstable power supply,At the time of insertion or removal, adverse influence is not exerted on the signal transmission on the system bus, and effects of load variation on the main power supply are reduced.