Datasheet

Analog Integrated Circuit Device Data
38 Freescale Semiconductor
10XSC425
Figure 13. Auto-retry State Machine
6.3.2 Auto-retry
The auto-retry circuitry is used to reactivate the output(s) automatically, in case of an overcurrent, overtemperature, or
undervoltage failure conditions to provide a high availability of the load.
Auto-retry feature is available in Fault mode. It is activated in case of an internal retry signal is set to a logic [1]:
retry[x] = OC[x] or OT[x] or UV.
The feature retries to switch-on the output(s) after one auto-retry period (t
AUTO
) with a limitation in term of the number of
occurrences (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 auto-retry, the overcurrent detection will be set to default values in order to sustain the inrush current.
Figure 13 describes the auto-retry state machine.
6.3.3 Diagnostic
6.3.3.1 Output Shorted to VPWR Fault
The 10XSC425 incorporates output shorted to VPWR detection circuitry in the OFF state. An output shorted to VPWR fault is
detected if the 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 the FSB pin reports the fault in real time. 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 the SPI (OS_DIS[0:3] bit).
6.3.3.2 OpenLoad Faults
The 10XSC425 incorporates three dedicated OpenLoad detection circuitries on the output to detect in OFF and in ON states.
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