The AAT4280 SmartSwitch is a P-channel MOSFETpower switch designed for high-side load switchingapplications. The P-channel MOSFET device has atypical RDS(ON) of 80mΩ, allowing increased loadswitch power handling capacity. This device is availablein three different versions with flexible turn onand off characteristics from very fast to slew rate limited.The standard AAT4280 (-1) version has a slewrate limited turn on load switch and is functionallycompatible with the AAT4250 device while offeringsuperior RDS(ON) characteristics. The AAT4280 (-2)version features fast load switch turn on capabilities,
typically less than 500ns turn on and 3μs turn offtimes. The AAT4280 (-3) variation offers a shutdownload discharge circuit to rapidly turn off a load circuitwhen the switch is disabled. All AAT4280 load switchversions operate with an input voltage ranging from1.8V to 5.5V, making them ideal for both 3V and 5Vsystems. The AAT4280 also features an under-voltagelockout which turns the switch off when an inputunder-voltage condition exists. Input logic levels areTTL and 2.5V to 5V CMOS compatible. The quiescentsupply current is very low, typically 2.5μA. Inshutdown mode, the supply current decreases toless than 1μA