About IS pin behavior of PROFET+2 in the datasheet

[Mac_Komatsubara]

 Regarding the behavior of the IS pin at the time of failure described in the attached file,

could you  tell us how the first small signal before IIS = IIS (FAULT) is output?

[Anshika_G · Accepted solution]

Hello,

The small rise at the sense is because the sense current follows the output current. At the same time the VDS reduces and at some point reaches the VDS(OLOFF) threshold -> indicated via the sense. At another point later the VDS is too low and the sense signal decreases, until the load current reaches IL(OVL) and triggers the internal counter -> followed by IIS(FAULT) indication at the sense.

Best Regards,
Anshika

[Anshika_G]

Hello,
A little more explanation which might be helpful:

When VDS < VDS(OLOFF) the power output stage is switched ON and a current IIS(OLOFF) is provided by the sense pin. If the load is properly connected and there is no short circuit to battery, VDS ~ VS therefore VDS > VDS(OLOFF). In case of a short circuit to battery the voltage divider between VS – OUT – GND is unbalanced and VDS goes below the minimum VDS(OLOFF) and the sense is falling again.

It can appear as a little confusing  as so many things happen in a very short time period and signals are rising and dropping very fast.

Best Regards,
Anshika