DRV8316C: CSA not inverted as described in datasheet

Hello TI,

currently we are evaluating your DRV8316C in a design. We switched from DRV8316 to DRV8316C as you suggested because the C Version has improved CSA linearity.

Furthermore, your DRV8316C datasheet says, that the CSA will not invert the measured current. Our reference voltage was 3V0, so 0A is 1V5. A positive current (OUTA => GND) is expected to lead to a increasing output voltage of SOA as descried in you DS:

DRV8316C:

In previous design we used the DRV8316 which had inverted behavior. 

DRV8316:

Currently, we are firing up first PCBA in our lab and first measurements show that the inverting behavior is not as described in your datasheet of the DRV8316C. Unfortunatly, a positiv current will NOT lead to a increasing voltage of SOA.

Setup:

We added an external power supply with current limitation; increased it step by step. OUTA: positive side of power supply. GND of PCBA: negative side power supply. Meassured curent by current clap from supply to OUTA (positive current flow through low-side FET).

We set INHx, INLB, INLC LOW and INLH HIGH, so only LS FET of OUTA will be conducting.

We increased current limitation step by step, the SOA voltage decreased.

Could you please confirm this behavior? 

Thanks,

Florian