4.1

Smart shutdown function

The device 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 overcurrent detection function.

The output signal of the comparator is fed to an integrated MOSFET with the open drain output available on the

SD input. When the comparator triggers, the device is set in shutdown state and its outputs are all set to low level.

Figure 6. Smart shutdown timing waveforms in case of overcurrent event

LIN

LVG

SD

open-drain gate

(internal)

comp

Vref

CIN

PROTECTION

Fast shutdown:

the driver outputs are set in SD state

immediately after comparator triggering

even if the SD signal has not yet reached

the lower input threshold

real disable time

t

OC

t2

t1

SD

FROM / TO

CONTROLLER

VBIAS

SMART

SD

LOGIC

CSD

RSD

R ON_OD

R PD_SD

SHUTDOWN CIRCUIT

where:

l

t CIN_SD

t1

t2

RON_OD = VOD/5 mA, see Table 10. Sense comparator (VCC = 15 V, unless otherwise is specified);

RPD_SD (typ.) = 5 V/ISDh

STGIB30M60S-L

Smart shutdown function

DS12605 - Rev 4

page 12/23