In common overcurrent protection designs, the comparator output is usually connected to the SD input and an RC

network is connected to this SD line in order to provide a mono-stable circuit which implements a protection time

that follows the fault condition.

As opposed to common fault detection systems, the device smart shutdown architecture allows the immediate

turn-off of output gates driver in case of fault, by minimizing the propagation delay between the fault detection

event and the actual switching off of the outputs. In fact, the time delay between the fault and the turning off of the

outputs is no longer dependent on the RC value of the external network connected to the pin.

In the smart shutdown circuitry, the fault signal has a preferential path which directly switches off the outputs after

the comparator triggering.

At the same time, the internal logic turns on the open-drain output and holds it on until the SD voltage goes below

the VSSD threshold and the toc time is elapsed.

The driver outputs restart following the input pins as soon as the voltage at the SD pin reaches the higher

threshold of the SD logic input.

The smart shutdown system provides the possibility to increase the time constant of the external RC network (i.e.,

the disable time after the fault event) up to very high values without increasing the delay time of the protection.

STIB1560DM2-L

Smart shutdown function

DS13085 - Rev 1

page 13/22