Figure 9-12 shows the device fault reporting behavior in the event of a fault in channel 2 (only) with LATCH and SEL pin set to LO. As shown, the fault signaling is deactivated when EN is toggled (in this case from HI to LO to HI). The faulted channel can be determined by toggling the EN pin with a short pulse (less than 10-us wide) that does not affect the output of the channel.

Figure 9-12 FLT Pin Behavior (Versions A, B, C)

Figure 9-13 shows the device fault reporting behavior in the event of an overcurrent fault when EN goes high. As shown, the fault signaling is active only after the initial inrush current limit phase is complete.

Figure 9-13 FLT Pin Behavior With an Overcurrent Event On Channel Enable (Versions A, B,C)

Figure 9-14 shows the device fault and retry behavior when there is a slow creep into an overcurrent event. As shown, the switch clamps the current until it hits thermal shutdown, and then the device remains latched off until the LATCH pin is low.

Figure 9-14 Current Limit – Latched Behavior

Figure 9-15 shows the behavior with LATCH tied to GND; hence, the switch retries after the fault is cleared and t_RETRY has expired.

Figure 9-15 Current Limit – LATCH = 0

When the switch retries after a shutdown event, the fault indication remains until V_OUTx has risen to V_VS – 1.8 V. After V_OUTx has risen, the FLT output is reset and current sensing is available. If there is a short-to-ground and V_OUT is not able to rise, the SNS fault indication remains indefinitely. Figure 9-16 illustrates auto-retry behavior and provides a zoomed-in view of the fault indication during retry.

Figure 9-16 Fault Indication During Retry