ISP1122
Universal Serial Bus stand-alone hub
Rev.
03 — 29 March 2000 Product specification
1.
General description
The ISP1122 is a stand-alone Universal Serial Bus (USB) hub device which complies with USB Specification Rev.
1.
1.
It integrates a Serial Interface Engine (SIE), hub repeater, hub controller, USB data transceivers and a 3.
3 V
voltage regulator.
It has a configurable number of downstream ports, ranging from 2 to 5.
The ISP1122 can be bus-powered, self-powered or hybrid-powered.
When it is hybrid-powered the hub functions are powered by the upstream power supply (VBUS), but the downstream ports are powered by an external 5 Volt supply.
The low power consumption in ‘suspend’ mode allo...