powerSTEP01
Functional description
7.20
FLAG pin
By default, an internal open-drain transistor pulls the FLAG pin to ground when at least one
of the following conditions occurs:
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•
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•
•
•
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•
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Power-up or standby/reset exit
Stall detection on bridge A
Stall detection on bridge B
Overcurrent detection
Thermal warning
Thermal shutdown
UVLO
UVLO on ADC input
Switch turn-on event
Command error
It is possible to mask one or more alarm conditions by programming the ALARM_EN
register (see Table 31). If the corresponding bit of the ALARM_EN register is low, the alarm
condition is masked and it does not cause a FLAG pin transition; all other actions imposed
by alarm conditions are performed anyway. In case of daisy chain configuration, FLAG pins
of different ICs can be or-wired to save host controller GPIOs.
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STMICROELECTRONICS [ ST ]
