NCV7694
DETAILED OPERATING DESCRIPTION
Under Voltage Lockout
short filter time the driver is switched off and fault on the
DIAG pin is reported.
Under voltage Lockout feature is used to protect against
an abnormal status during startup. When the initial soft start
voltage is greater than 4.5 V (typ) the device starts to be
active. Below this threshold the GATE output pin is pulled
low to ground to prevent opening external N−MOS
transistor and DIAG pin is pulled low to report.
Exceeding the Flash Pulse
If the duration of the FLASH pulse exceeds the
pre−defined timing or the FLASH pulse repetition is too
frequent, the GATE of the transistor is switched off. The
limitation of the FLASH pulses is also reported on the DIAG
pin. The first FLASH pulse after power−on−reset should be
delayed longer than FRL period, otherwise the FLASH
pulse will be limited and DIAG pin will report a fault until
FRL counter expires.
Thermal Shutdown
The thermal shutdown circuit checks the internal junction
temperature of the device. When the internal temperature
rises above the Thermal shutdown threshold, then after a
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