Figure 7-11 Fault reaction with Latch
setting (shown for OCP occurrence on high-side when OUT is shorted to
ground)
Short occurrence and recovery scenario
with LATCH setting:
t1: An external short
occurs.
t2: OCP (Over Current
Protection) fault confirmed after tOCP, output disabled, nFAULT
asserted low to indicate fault.
t3: A CLR_FLT command (SPI
variant) or nSLEEP RESET Pulse (HW variant) issued by controller. nFAULT is
de-asserted and output is enabled. OCP fault is detected again and output is
disabled with nFAULT asserted low.
t4: The external short is
removed.
t5: A CLR_FLT command (SPI
variant) or nSLEEP RESET Pulse (HW variant) issued by controller. nFAULT is
de-asserted and output is enabled. Normal operation resumes.
SPI variant only – Fault
status remains latched till a CLR_FLT command is issued.
Note that, in the event of an output
short to ground causing the high-side OCP fault detection, IPROPI pin will continue
to be pulled up to VIPROPI_LIM voltage to indicate this type of short,
while the output is disabled. This is especially useful for the HW (H) variant to
differentiate the indication of a short to ground fault from the other faults.