Datasheet

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USB POWER-DISTRIBUTION REQUIREMENTS
TPS2045A , , TPS2046A
TPS2047A , TPS2048A , TPS2055A
TPS2056A , TPS2057A , TPS2058A
SLVS251C – SEPTEMBER 2000 – REVISED JANUARY 2008
USB can be implemented in several ways, and, regardless of the type of USB device being developed, several
power-distribution features must be implemented.
• Hosts/self-powered hubs must:
– Current-limit downstream ports
– Report overcurrent conditions on USB V
BUS
– Enable/disable power to downstream ports
– Power up at <100 mA
– Limit inrush current (<44 Ω and 10 µ F)
– Limit inrush currents
– Power up at <100 mA
• Bus-powered hubs must:
– Enable/disable power to downstream ports
– Power up at <100 mA
– Limit inrush current (<44 Ω and 10 µ F)
– Limit inrush currents
– Power up at <100 mA
• Functions must:
– Limit inrush currents
– Power up at <100 mA
The feature set of the TPS204xA and TPS205xA allows them to meet each of these requirements. The
integrated current-limiting and overcurrent reporting is required by hosts and self-powered hubs. The logic-level
enable and controlled rise times meet the need of both input and output ports on bus-power hubs, as well as the
input ports for bus-power functions.
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Product Folder Link(s): TPS2045A TPS2046A TPS2047A TPS2048A TPS2055A TPS2056A TPS2057A TPS2058A