L9610C - L9611C
After the overcurrent protection time is reached, the
powerMOS is switched-off ; this condition is latched
by setting an internal flip-flop and is externallymoni-
tored by the low state of the MON pin.
To resetthe latch the supply voltage hasto fall below
VSL or the device must be switched off.
UNDER AND OVERVOLTAGE SENSE WITH
LOAD DUMP PROTECTION
The undervoltage detection feature resets the timer
and switches off the output driving signal when the
supply voltage is less than VSL.
If the supply voltage exceeds the max operating
supply voltage value, an internal comparator dis-
ables the charge pump, the oscillator and the exter-
nal powerMOS.
Figure 1 : Typical Transfer Curve.
In both cases the thresholds are provided with suit-
able hysteresis values.
The load dump protection function allows the device
to withstand - for a limited time - high overvoltages.
It consists of an active clamping diode which limits
the circuit supply voltage to VCLAMP and an external
current limiting resistor R1. The maximum pulse
supply current (see abs. max. ratings is equal to
0.3A. Therefore the maximum load dump voltage is
given by :
VDUMP = VSC + 0.3R1
In this condition the gate of the powerMOS is held
at the GND pin potential and thus the load voltage
is :
VL = Vs - VCLAMP - VGS
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