The UCS81003 provides a USB port power switch for control of 2.7 amperes continuous current with over-current limit (OCL), dynamic thermal management, latch or auto-recovery (low test current) fault handling, selectable active low or high enable, under- and over-voltage lockout, back-drive protection, and backvoltage protection.

Split supply support for VS and VDD is an option for low power in system standby states. This gives battery operated applications, like onboard computers, the ability to detect attachments from a sleep or off state. After the Attach Detection is flagged, the system can decide to wake up and/or provide charging.

In addition to power switching and current limiting modes, the UCS81003 will automatically charge a wide variety of portable devices, including USB-IF BC1.2, YD/T-1591 (2009), most Apple®, Samsung and RIM®, and many others. Nine preloaded charger emulation profiles maximize compatibility coverage of peripheral devices. As well, a customizable charger emulation profile is available to accommodate unique existing and future portable device handshaking / signature requirements.

The UCS81003 also provides current monitoring to allow intelligent management of system power and charge rationing for controlled delivery of current regardless of the host power state. This is especially important for battery operated applications that want to provide power and do not want to drain the battery excessively.

The UCS81003 is available in a 28-pin QFN 5 mm x 5 mm package.

• Port power switch with two current limit behaviors
  • 2.9 V to 5.5 V source voltage range
  • 2.7 A current with 55 mΩ On Resistance
  • Over-current trip or constant current limiting
  • Soft turn-on circuitry
  • Programmable current limit
  • Dynamic thermal management
  • Under- and over-voltage lockout
  • Back-drive, back-voltage protection
  • Latch or auto-recovery (low test current) fault handling
  • Selectable active high or low power switch enable
  • BC1.2 VBUS discharge port renegotiation function
• Selectable / automatic cycling of USB data line charger emulation profiles
  • Employs unique method and system for sampling multiple profiles
  • USB-IF BC1.2 charging downstream port (CDP) & dedicated charging port (DCP) modes, YD/T-1591, and most Apple, Samsung and RIM protocols standard; others as defined via the SMBus 2.0 / I2C® protocol
  • USB 2.0 compliant high-speed data switch (in Data Pass-through, SDP, and CDP modes)
  • Nine preloaded charger emulation profiles for maximum compatibility coverage of peripheral devices
  • One custom programmable charger emulation profile for portable device support for fully host controlled charger emulation
• Self-contained current monitoring and rationing for power allocation applications
• Low power Attach Detection and open-drain A_DET# pin
• Ultra low power Sleep state
• Optional split supply support for VBUS and VDD for low power in system standby states
• Wake on Attach USB
• SMBus 2.0 / I2C communications
  • Supports Block Write and Read
  • Multiple SMBus addresses
• Wide operating temperature range: -40 °C to +85 °C