STEVAL-KITXCB SD pin question

[Kuzma30]

In STEVAL-KITXCB for controlling SD/OD pin of L6491 using such method. PWM_en connected to MCU pin.

 I want use same principle in my design. Can anybody describe how program this.
Is such hw connection support both function for enable PWM and for controll error state of driver? (I need both)

[Peter BENSCH]

You have probably misunderstood the function of the pin SD/OD. Section 7 of the data sheet of the L6491 describes this in more detail. It is not a matter of reporting a status back to the microcontroller, but rather that OD keeps the SD input deactivated. PWM_en/SD in the schematic above therefore only functions as an input.

Excerpt from the data sheet::

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 smart SD unlatch threshold VSSD.
When such threshold is reached, the open-drain output is turned off, allowing the external pull-up to recharge the capacitor.

Hope that answers your question?

Regards
/Peter

[Kuzma30]

When choosing a IC

 

, I read about the 2EDL23x06PJ (Infineon), which did not fit the current parameters. On the block diagram, this pin is similar to the L6491, and in the documentation it is described as "SD pin is Shutdown logic input (active low)/open-drain comparator output (page 3)"
On figure shown description for 2EDL23x06PJ.

So in L6491 I can use SD pin only for enable/disable chip?  
Then question - how to inform MCU about fault state?