There are two main roles of USB. Recently, USB switch IC is used as aload switch with protections.
1. USB Power Line's ON/OFF Control
By the enable signal from another device such as a USB Host Controller, the USB switch turn on the USB power line with suppressing inrush current with soft-start function. On the contrary, by the disable signal, the USB switch cut off the power line with or without auto-discharge function (Option).
2. USB Power Line Protection
There is protection capability against the abnormal heating in the USB switch, and if preset over-current is detected, output current is limited or power is cut off and latched for protection.
*1) FLG pin has N-channel open drain output, therefore pull-up resistance is necessary when it is used. The output of FLG pin becomes "L" when the thermal shutdown or over-current limit-function works.
*2) According to the USB standard,120µF or more capacitor attachment is recommended, however, as an IC, changing capacitor is acceptable considering other usage.
|Operating Voltage Range||UVLO Detect Voltage||Current Limit Threshold||Short Current Limit||Internal
|R5520||100 mΩ||20 µA||4.0 V to 5.5 V||2.2 V||1.2 A||750 mA||Pch||SOT-89-5||Consumer|
|R5523||130 mΩ||20 µA||2.2 V to 5.5 V||1.8 V||1 A||750 mA||Pch||SOT-23-5||Consumer
|R5524||100 mΩ||110 µA||2.7 V to 5.5 V||2.4 V||800 mA||650 mA||Nch||DFN(PLP) 1820-6