Datasheet
NXP Semiconductors 35
10XS3435
All latched faults (overtemperature, overcurrent, severe short-circuit, over and undervoltage) are reset if:
•V
DD
< V
DD(FAIL)
with V
PWR
in nominal voltage range,
•V
DD
and V
PWR
supplies is below V
SUPPLY(POR)
voltage value.
Figure 16. Autoretry state machine
7.3.2 Autoretry
The autoretry circuitry is used to reactivate the output(s) automatically in case of overcurrent or overtemperature or undervoltage failure
conditions to provide a high availability of the load.
Autoretry feature is available in Fault mode. It is activated in case of internal retry signal is set to logic [1]:
retry[x] = OC[x] or OT[x] or UV.
The feature retries to switch-on the output(s) after one autoretry period (t
AUTO
) with a limitation in term of number of occurrence (16 for
each output). The counter of retry occurrences is reset in case of Fail-safe to Normal or Normal to Fail-safe mode transitions. At each
autoretry, the overcurrent detection will be set to default values in order to sustain the inrush current.
The Figure 16 describes the autoretry state machine.
7.3.3 Diagnostic
7.3.3.1 Output shorted to VPWR
fault
The 10XS3435 incorporates output shorted to VPWR detection circuitry in OFF state. Output shorted to VPWR fault is detected if output
voltage is higher than
V
OSD(THRES)
and reported as a fault condition when the output is disabled (OFF). The output shorted to VPWR fault
is latched into the status register after the internal gate voltage is pulled low enough to turn OFF the output. The OS[0:3] and OL_OFF[0:3]
fault bits are set in the status register and
FS pin reports in real time the fault. If the output shorted to VPWR fault is removed, the status
register will be cleared after reading the register.
The open output shorted to VPWR protection can be disabled through SPI (OS_DIS[0:3] bit).
OFF
ON
Latched
OFF
Autoretry
OFF
Autoretry
ON
(SC = 1)
(OV = 1)
(fault_control = 1 and OV = 0)
(fault_control = 0 or OV = 1)
(fault_control = 0)
(fault_control = 0)
(fault_control = 0)
(SC = 1)
(Retry = 1)
= > count = count+1
(Retry = 1)
(count = 16)
(after Retry Period and OV = 0)
(OpenloadOFF = 1
or ShortVpwr = 1
(OpenloadOFF = 1
or ShortVpwr = 1
(OpenloadOFF = 1
or ShortVpwr = 1
(OpenloadON = 1)
(OpenloadON = 1)
or OV = 1)
or OV = 1)
or OV = 1)
if hson = 1
if hson = 0
if hson = 1