Rainbow Electronics MAX5958 - Manual (Page 19)

MAX5957/MAX5958
Triple PCI Express, Hot-Plug Controllers
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ENABLE CHARGE ON
INTERNAL AUXILIARY
MOSFET DRIVING 3.3AUXO_.
START COUNTING t SU
FAULT ON 12V
OR 3.3V OUTPUTS
RESET t FAULT
COUNTER
FAULT
STILL PRESENT?
Y
Y
Y
Y
Y
SHUT DOWN
12V AND 3.3V OUTPUTS.
ASSERT FAULT_
STAY WAITING FOR
t RESTART
t FAULT ELAPSED?
N
N
N
N
3.3VAUXIN IS OK,
AUXON_ IS HIGH,
PRES_DET IS LOW
RESET FAULT_
START COUNTING
t FAULT
Y
N
N
N
ARE ALL
MAIN OUTPUTS OK?
NO FAULT
DETECTED
LATCH-OFF
OPTION?
N
ON_ TOGGLED
HIGH ≥ LOW ≥ HIGH
MAIN INPUTS ARE
OK, ON_ IS HIGH
Y
Y
N
ENABLE CHARGE
ON 3.3G_ AND 12G_.
START
COUNTING t SU
t SU
ELAPSED?
Y
START PGOOD
THRESHOLD
MONITORING
START COUNTING
t FAULT
ALL PGOOD
THRESHOLDS
REACHED?
N
N
N
N
Y
Y Y
Y
ASSERT PWRGD_
AFTER t POR_HL
DELAY
RESET PWRGD_
POWER ON
AUXILIARY OUTPUT.
FAULT_ AND PWRGD_ ARE
HIGH IMPEDANCE
SHUT DOWN ALL OUTPUTS.
ASSERT FAULT_.
STAY WAITING
FOR t RESTART
RESET FAULT_
ON_ AND
AUXON_ TOGGLED
HIGH ≥ LOW
≥ HIGH
t SU
ELAPSED?
AUX OUTPUT OK?
NO FAULT DETECTED
FAULT ON 3.3AUXO_?
N
N
t FAULT ELAPSED?
Y FAULT
STILL PRESENT?
N
Y Y LATCH-OFF
OPTION?
RESET t FAULT
COUNTER
Figure 6. Fault Management Flowchart