The
TCAN284x-Q1
monitors VCC1, VEXCC and VCC2 (CAN LDO) for short to ground conditions. Short to ground
is represented by VCC1
33SC, VCC1
5SC, VCC2
SC and
VEXCC
SC. A short to ground turns off the LDO. When a VCC1
SC
occurs, VCC1 is turned off for a minimum of t
LDOOFF, and the device enters
fail-safe mode (if enabled) or sleep mode. During this time, wake events are monitored
and preserved. A short circuit event cannot be monitored while the LDO is off. A wake
event causes VCC1 to be turned on for t
LDOON to see if the SC event is still
present. If still present, the device transitions to sleep mode. If not present, the
device transitioned to restart mode. While in fail-safe mode, the SWE timer starts and
if the fault is not cleared and a wake event has not taken place before the timer times
out the device transitions to sleep mode. If fail-safe mode is disabled, the device
transitions to sleep mode. See
Figure 8-54,
Figure 8-55 and
Figure 8-56 for
device behavior during a short to ground event.
Note: When VCC1_CFG = 01b for VCC1 always on, or FSM CNTR exceeded, a wake event
is not needed to exit the fail-safe mode. The device exits the fail-safe mode after
tLDOOFF timer expires.