Protection circuits, USB interface integrated circuits, and methods for protecting host circuitry from USB port pin overvoltages, in which a switch is connected between a USB port pin and a middle node, and a detection circuit compares the middle node voltage with a reference voltage. A control circuit turns off the switch and turns on a clamp circuit to conduct pull down current from the middle node in response to the middle node voltage exceeding the reference voltage to mitigate overvoltage conditions on a host pin coupled to the middle node. When the middle node voltage falls below the reference voltage, the control circuit delays for a predetermined time and then turns off the clamp circuit and turns on the switch.