The device includes a programmable fuse protection, that is based on a defined time-current curve and is commonly referred to as I2t protection in melting fuse data sheets. The intent is to match the switch turnoff behavior of a melting fuse. There are two parameters that can be configured (for each channel) in the I2T_CONFIG_CH1 and I2T_CONFIG_CH2 registers - that sets the time-current curve. One, the nomimal current (NOM_CUR_CHx), is the current below which the device can supply current indefinitely without turn-off. This is roughly equivalent to the fuse current rating of the melting fuses. The second parameter, I2T_TRIP_CHx, is the integral energy value above which the switch is turned off. Other parameters that define the region are (1) the maximum current that is measurable (ISWCL_CHx) that is determined by the current sense ratio (KSNS) of the device and the resistor chosen on the sense pin and (2) the SWCL_DLY_TMR_CHx that sets the time after which the channel shutdown when the current exceeds ISWCL_CHx. The channel remains off for a period set by TCLDN_CHx bits before retrying. The device can be configured to latch-off (retry only on MCU re-enable of the channel) by setting the two-bit TCLDN_CHx to 00.

The operational region for the fuse-based shutdown is shown in the Figure 8-2 below. Exemplary values for the current values that bound the operational region is included.

Figure 8-2 Current Operational Region of Fuse Based Switchoff