SLVSB64I November 2011 – March 2018 TPS65217
The interrupt pin is used to signal any event or fault condition to the host processor. Whenever a fault or event occurs in the device, the corresponding interrupt bit is set in the INT register, and the open-drain output is pulled low. The nINT pin is released (Hi-Z) and the fault bits are cleared when the INT register is read by the host. However, if a failure continues, the corresponding INT bit stays set and the nINT pin is pulled low again after a maximum of 32 µs.
Interrupt events include pushing or releasing the push-button and a change in the USB or AC voltage status.
The mask bits in the INT register are used to mask events from generating interrupts. The mask settings affect the nINT pin only and have no impact on the protection and monitor circuits themselves.
Continuous event conditions such as an ISINK-enabled shutdown can cause the nINT pin to be pulled low for an extended period of time, which can keep the host in a loop trying to resolve the interrupt. If this behavior is not desired, set the corresponding mask bit after receiving the interrupt and poll the INT register to determine when the event condition resolves and the corresponding interrupt bit is cleared. Then the interrupt that caused the nINT pin to stay low can be un-masked.