AT43312A

Features Full Compliance with USB Spec Rev 1.1 Four Downstream Ports Full-speed and Low-speed Data Transfers Bus-powered Controller Bus-powered or Self-powered Hub Operation Per Port Overcurrent Monitoring Individual Port Power Control USB Connection Status Indicators 5V Operation with On-chip 3.3V Format 32-lead SOIC and LQFP Green (Pb/Halide-free/RoHS Compliant) Package Options Available Overview Introduction The AT43312A is a 5 port USB hub chip supporting one upstream and four downstream ports. The AT43312A connects to an upstream hub or Host/Root Hub via Port0 and the other ports connect to external downstream USB devices. The hub re-transmits the USB differential signal between Port0 and Ports[1:4] in both directions. A USB hub with the AT43312A can operate as a bus-powered or self-powered through chip’s power mode configuration pin. In the self-powered mode, port power can be switched or unswitched. Overcurrent reporting and port power control can be individual or global. An on-chip power supply eliminates the need for an external 3.3V supply. The AT43312A supports the 12-Mb/sec full speed as well as 1.5-Mb/sec slow speed USB transactions. To reduce EMI, the AT43312A’s oscillator frequency is 6 MHz even www.DataSheet4U.com though some internal circuitry operates at 48 MHz. The AT43312A consists of a Serial Interface Engine, a Hub Repeater, and a Hub Controller. Self- and Buspowered USB Hub Controller AT43312A SOIC PWR2 PWR3 PWR4 VCC5 VSS OSC1 O...