The FAN3989 is a USB connection monitoring device used to determine if a standard USB device is connected or a battery-changing device is connected. The FAN3989 sets the FLAG1 pin to logic HIGH or LOW as an indicator to the system controller that a standard USB device or a charger is connected to the USB port. The FAN3989 also monitors the VBUS for over- or under-voltage conditions. The FLAG2 pin is set LOW if VBUS is less than 3.3V or greater than 6.0V. The internal load switch control pin is set HIGH if VBUS is less than 3.3V or greater than 6.0V, turning off the PMOS switch.The FAN3989 is available in a very small 8-lead MLP package suitable for small board space applications, like mobile phones.