USB charging-port controller and power switch has short-to-battery protection

The Texas Instruments TPS254900-Q1 device is a USB charging-port controller and power switch with short-to-battery protection. This feature provides protection on OUT, DM_IN and DP_IN. These three pins withstand voltage up to 18 V. The internal MOSFET turns off quickly when the short-to-battery condition occurs. Rapid turnoff is very important to protect the upstream dc-dc converter, processor, or hub data lines. This 45mohm power switch has two selectable, adjustable current limits that support port power management by changing to a lower current limit when adjacent ports are experiencing heavy loads. This is important in systems with multiple ports and upstream power supplies with limited capacity. It has a current-sense output that is able to control an upstream supply, which allows it to maintain 5V at the USB port even with heavy charging currents. This feature is important in systems with long USB cables where significant voltage drops can occur with fast-charging portable devices. A current monitor allows a system to monitor the load current in real time by monitoring the IMON voltage. The current monitor is very useful and can be used for dynamic port-power management. The device also provides ESD protection capability per IEC 61000-4-2, level 4 on DP_IN and DM_IN.