When bit 0 of the Remote Diode Temperature Filter and Alert Mode Setting register is set to 0, the Alert Mode is set to Interrupt mode. In this mode, the ALERT pin is asserted at the end of a conversion cycle if the measured temperature exceeds a High Alert Limit or goes below a Low Alert Limit defined in the limit registers. In this mode, the TMP4718 will set the ALERT mask bit of the Configuration Register during a read of the Status Register if any flag in Status Register, except the ADC_Busy flag and Remote Diode Open flag, is set. This prevents the ALERT pin from triggering until the controller has reset the ALERT mask bit (write 0 to Alert_MSK bit).

The ALERT High Status flags will set at the end of a conversion cycle when the measured temperature exceeds a High Alert Limit register limit. There are separate High Limit values and status register flags for the remote and local temperature measurements. The status register flags will only set to their respective temperature measurements.

The Remote ALERT Low Status flag will set at the end of a conversion cycle when the measured remote temperature is below the Remote Low Alert Limit register limit.

The Status Register limit flags are cleared after a read command of the Status Register from the controller and will be set again at the end of a proceeding temperature conversion cycle if the measured temperature is outside the set limits.

Figure 8-5 shows the behavior of the ALERT pin and flags while in Interrupt mode.

Figure 8-5 Alert Interrupt Mode Timing Diagram