Patent Application
20080059603
These and other features, aspects and advantages of the invention will become apparent by reference to the following description and accompanying drawings which are given by way of illustration only, and thus are not limitative of the invention, and wherein:
The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements.
The portable disk 205 has several passive elements 290 in the memory device 260, coupled to the memory controller 260 and the memory 280. These passive elements are resistors, capacitors, and inductors, used to produce stable signals or voltages on the memory device 260.
The hub controller 220 is used to control the data storage or access between devices. Therefore, the hub controller 220 can control the data storage or access between the host 200 and the memory device 260. The hub controller 220 can also control the data storage or access between the host 200 or the memory device 260 and downstream devices (via the hub ports 252, 254, 256 and the hub controller 220).
Using the hub controller 220, the data can be transmitted among the host 200, the memory device 260, and the downstream devices (not shown). The host 200 here can be a device with logic processing ability, such as a computer or server. The downstream devices include the keyboard, mouse, MP3 player, cell phone, or digital camera that has a USB interface.
The memory 280 inside the portable disk 205 can have many choices, as long as the interface between the memory, the host, and the downstream devices. It can be a flash memory or hard-drive type memory. The flash memory is the most popular one nowadays.
The power management of the portable disk 205 has different regulations. As the host 200 provides power to a portable disk 205, if the upper limit of the electrical current provided by each of the hub ports 252, 254, 256 is defined to be 100 mA, then a downstream device may not be detected and used when it requires more than 100 mA. That is, the portable disk 205 provides a bus power from the host 200. However, according to the USB Association's definition, the portable device 205 is a low power device.
Suppose the upper limit of the electrical current provided by each of the hub ports 252, 254, 256 of the host 200 to the portable disk 205 is above about 500 mA, then the downstream device can obtain more than 500 mA from the corresponding hub port. That is, the portable disk 205 provides a self power form the host 200. According to the USB Association's standard, such a portable disk 205 is not a low power device.
According to the need, whether the portable disk 205 provides a bus power or self power from the host 200 can be determined by the designer, making it a low power device or a device that can provide a larger current.
According to another embodiment of the invention, the portable disk 205 is an integration of a hub controller 220, several hub ports 252, 254, 256, a memory controller 270, and a memory 280.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
While the invention has been described by way of example and in terms of the preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 95215467 | Aug 2006 | TW | national |
