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APPLICATION AND BLOCK DIAGRAM

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Fully USB Compliant

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Support Four 5V Peripherals and

One USB 3.3V Controller

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Separate Power Enables

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500mA Current Limiting per

Channel

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Separate Open Drain Fault

Indicator for Each Channel

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3.3V Output for USB Controller

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Available in 28 Pin Wide Surface

Mount and DIP

Universal Serial Bus Power Controller

FEATURES

DESCRIPTION

UCC3831

PRELIMINARY

UDG-97101

The UCC3831 Power Controller is designed to provide a self powered

USB hub with a local 3.3V regulated voltage and four 5V regulated volt-

ages for USB ports. Each of the 5V output ports is individually enabled

for optimal port control. Each port also provides an overcurrent fault sig-

nal indicating that the port has exceeded a 500mA current limit. The

3.3V linear regulator is used to power the local USB microcontroller.

This regulator is protected with a 100mA current limit and has a logic

level enable input.

The UCC3831 can be configured to provide USB port power from a

loosely regulated voltage such as a Filament voltage internal to a moni-

tor. Pre-regulation is provided by an internal linear regulator controller

and one external logic level N-channel MOSFET. The UCC3831 can

also be configured without using the pre-regulator stage by connecting

the VREG pins to a regulated 5.5V 2A source.

The UCC3831 comes in a 28-pin wide SOIC power package optimized

for power dissipation, and is protected by internal over-temperature

shutdown mechanism, which disables the outputs should the internal

junction temperature exceed 150°C.