This device is a self-contained USB Hub which complies with USB Hub Specification Rev 1.0. This device is used to expand the USB ports of your PC system while needed. Because of its self-contained and bus-powered/self-powered capability, it can hide the complexity from the user and be flexibly placed anywhere, such as monitor, keyboard, motherboard, Hub-box, etc. The MC141555 consists of Serial Interface Engine (SIE), Hub Repeater, and Hub Controller, supporting one upstream port and up to five downstream ports.
Both Low Speed Mode (1.5Mbps) and Full Speed Mode (12Mbps) are sup-ported by automatically detecting which data line (D+ or D-) is pulled high whenever downstream devices are connected to the bus or at power-up.
MC141555 Hub can be Self Powered or Bus Powered. When self-powered, MC141555 is powered by an external 5 volt supply and capable of deliver 500mA current to each downstream port. Power management for all down-stream ports supports power-switching and overcurrent detection with Individ-ual or Ganged control; a self-powered MC141555 supports Individual control only, but bus-powered MC141555 supports either Individual or Ganged control. When Ganged control, PWRSW1 and OVR1 are dedicated for power manage-ment.