UCC3981 Datasheet, PDF (1/5 Pages) Texas Instruments – Universal Serial Bus Hot Swap Power Controller

UCC3981
Universal Serial Bus Hot Swap Power Controller
PRELIMINARY
FEATURES
• Fully USB Compliant
• Support Four 5V Peripherals and One
USB 3.3V Controller
• Separate Power Enables
• 500mA Current Limiting per Channel
• Separate Open Drain Fault Indicator
for Each Channel
• 3.3V Output for USB Controller
• Available in 28 Pin Wide Surface
Mount and DIP
DESCRIPTION
The UCC3981 Hot Swap Power Controller is designed to provide a self
powered USB hub with a local 3.3V regulated voltage and four 5V regu-
lated voltages for USB ports. Each of the 5V output ports is individually
enabled for optimal port control. Each port also provides an overcurrent
fault signal 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 UCC3981 can be configured to provide USB port power from a
loosely regulated voltage such as a Filament voltage internal to a monitor.
Pre-regulation is provided by an internal linear regulator controller and
one external logic level N-channel MOSFET. The UCC3981 can also be
configured without using the pre-regulator stage by connecting the VREG
pins to a regulated 5.5V 2A source.
The UCC3981 comes in a 28-pin wide SOIC power package optimized
for power dissipation, and is protected by internal over-temperature shut-
down mechanism, which disables the outputs should the internal junction
temperature exceed 150°C.
APPLICATION AND BLOCK DIAGRAM
11/98
UCC3981 USB HUB POWER CONTROLLER
UDG-97101