ZHCSRU8 February 2024
PRODUCTION DATA
Both low-side overcurrent (OC) and high-side short-circuit protection are implemented.
The low-side overcurrent fault and warning thresholds are programmed through PMBus and sensed across cycle-by-cycle average current through the low-side MOSFET and compared to the set warning or fault threshold while high-side pulses are terminated on a cycle-by-cycle basis, if the peak current through the high-side MOSFET exceeds the 1.5 × the programmed low-side threshold.
When either a low-side overcurrent or high-side short-circuit threshold is exceeded during a switching cycle, an OCP fault counter is incremented. If no overcurrent condition is detected in a switching cycle, the counter is decremented. If the counter exceeds the delay selected by the (47h) IOUT_OC_FAULT_RESPONSE PMBus value (default = 3), overcurrent fault condition is declared and the output shuts down. Restart and timing is also defined as part of (47h) IOUT_OC_FAULT_RESPONSE.
The output OC fault thresholds and fault response are set through PMBUS. The OC fault response can be set to shutdown, restart, or ignore.