Question: In our PMBus enabled POLs (MAX20730,MAX20730, etc.) do the faults (e.g; OCP) get erased when EN goes low?
Answer:
- Disabling the output does not clear the flags
- Re-enabling will clear the flags
- The output can be disabled and re-enabled through many means: EN input, PMBus command, etc.
- Cycling power to the IC clears all flags (by virtue of collapsing the voltage that powers the internal memory and/or forcing a power-on reset of the IC)
- As for the EN pin, while the faults don’t get erased when the EN transitions “LOW”, its transition back to “HIGH” does in fact trigger the erasing/clearing of the logged faults. Essentially, if you toggle the EN, the logged faults will be gone.
- In summary, the fault and warning flags should remain set until the output is toggled off and then back on, with the actual “clearing action” occurring at the rising edge of the combined enable logic (all PMBus and hardware signals required to successfully enable the output).