Electrical computers and digital processing systems: support – Computer power control
Reexamination Certificate
1999-01-19
2001-06-26
Ray, Gopal C. (Department: 2181)
Electrical computers and digital processing systems: support
Computer power control
C713S310000, C714S014000
Reexamination Certificate
active
06253329
ABSTRACT:
CLAIM OF PRIORITY
This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from applications for A USB HUB HAVING A PLURALITY OF INPUT POWER SOURCES earlier filed in the Korean Industrial Property Office on Jan. 16, 1998, and there duly assigned Ser. No. 98/1261.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates, in general, to a universal serial bus (USB) hub, and more particularly to a USB hub having a plurality of input power sources which are capable of using bus power or self-power as power for the USB hub in accordance with a user's selection.
2. Related Art
The term “USB” relates to a standard for a universal-type serial bus. In order to facilitate connections between an existing personal computer and peripheral equipment, and in order to cope with a future multi-media environment, such companies as Intel, Microsoft, Compaq and NEC developed a common spec in which transmission speed reaches, at a maximum, 12 Mbps.
The term “USB hub” signifies hardware that serves as a medium for connecting peripheral equipment (a maximum of 127 in number) to a single personal computer in accordance with a USB standard. It provides both data and power distribution.
The cable connection topology of the USB has a construction which amounts to branching through the USB hub. At the lower part of the USB hub, it is possible to connect a function or another USB hub, resulting in a multi-star type topology.
As to the topology described above, a main body of the personal computer having a root hub is placed at the uppermost part thereof, and a hub controller provided in the main body of the personal computer provides communication between USB hubs.
The USB hub functions to carry out its internal function or to distribute power supplied to other hubs and functions connected at the lower part. Thus, the USB hub is supplied with bus power Vbus (upstream power from an upper hub) through a USB cable, or is supplied with self-power Vself from a local power supply unit (an additional independent power supply unit) through a power cable.
Hereinafter, the above-described USB hub supplied with bus power is termed a “bus power USB hub”, and the USB hub supplied with self-power is termed a “self-power USB hub”.
As described in more detail below, under certain conditions, a user needs a bus power USB hub. Under other conditions, a self-power USB hub is needed or will suffice. Whether or not the user is able to obtain one type of USB hub or the other is sometimes dependent on which type is manufactured and/or provided by the manufacturer.
Thus, there is a need for a USB hub having a plurality of power sources, wherein the user can conveniently select the power source between a local power source or an upstream cable, and can use the selected power source for internal power requirements or for distribution of power to other USB functions.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a USB hub having a plurality of input power supplies. A user can simply supply, for his use, self-power generated at a local power supply unit upon necessity. Bus power, inputted through an upstream cable, can also be selected by the user by simply connecting a cable thereto without an additional switch operation. Thus, the power supply method is determined by the user and not by the manufacturer.
In order to attain the above object, there is provided a USB hub having a plurality of input power sources. The USB hub receives power through an upstream cable or from a local power source unit and uses it as an internal consumption power source of the USB hub, and also can distribute it to other USB functions through each downstream port. A power source interface is provided for inputting both bus power provided through an upstream cable and self-power generated by a local power source unit. Whether or not self-power will be supplied is determined according to whether a user connects an additional power source cable to the USB hub.
Additional advantages, objects and other features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The object and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.
REFERENCES:
patent: 5799196 (1998-08-01), Flannery
patent: 6000042 (1999-12-01), Henrie
Bushnell , Esq. Robert E.
Ray Gopal C.
Samsung Electronics Co,. Ltd.
LandOfFree
Universal serial bus (USB) hub having a plurality of input... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Universal serial bus (USB) hub having a plurality of input..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Universal serial bus (USB) hub having a plurality of input... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2475995