Using Dual Current Limited TPS2140/41/50/51 For USB & Portable Applications

An issue in USB and other hot-swap environments is the unpredicted inrush current during plug-in. Depending on the load capacitance, the initial turn-on inrush current varies from miliamps to several amps. The high inrush current can drag the input supply voltage down to reset the upstream system. USB 1.0 and 2.0 specifications limit the inrush current by limiting the maximum input capacitance on the USB power source to 10-?F. The Texas Instruments TPS2140/41/50/51 family of switches are designed to help meet this inrush current requirement and allow the designer to optionally have a larger load capacitor.