l6391n STMicroelectronics, l6391n Datasheet - Page 13

• Manufacturer Part Number: l6391n
• Description: High-voltage High And Low Side Driver
• Manufacturer: STMicroelectronics

L6391
7
Smart shut down function
L6391 integrates a comparator committed to the fault sensing function. The comparator
input can be connected to an external shunt resistor in order to implement a simple over-
current detection function.
The output signal of the comparator is fed to an integrated MOSFET with the open drain
output available on pin 2, shared with the SD input. When the comparator triggers, the
device is set in shut down state and both its outputs are set to low level leaving the half-
bridge in tri-state.
Figure 6.
the driver outputs are set in SD state
Smart shut down timing waveforms
immediately after the comparator
triggering even if the SD signal
the lower input threshold
open drain gate
HVG/LVG
(internal)
HIN/LIN
SD/OD
threshold
threshold
upper
CP+
lower
CP-
has not yet reach
Fast shut down:
CONTROLLER
Doc ID 17892 Rev 1
FROM/TO
1
SHUT DOWN CIRCUIT
V
BIAS
R
C
SD
SD
SD/OD
PROTECTION
real disable time
TIME CONSTANTS
R
ON_OD
1
2
= (R
= R
SD
ON_OD
Smart shut down function
C
SMART
LOGIC
SD
// R
SD
2
SD
)
C
SD
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