Hi all
Would you mind if we ask DRV8711?
And thank you for your cooperation about DRV8711's support always.
We recognize the condtion which Predriver Fault(XPDF) occurs.
-The predriver fault (xPDF) indicates a failure on the gate of the FET.
-The predriver fault monitors proper operation of the x1LS/x2LS/x1HS/x2HS outputs of the DRV8711.
-If incorrect operation is detected the PDF fault is activated.
-Examples of detectable predriver faults are gate to source short, gate to drain short, pin short to adjacent pin.
https://e2e.ti.com/support/motor-drivers/f/38/t/655432
In addition to it, we would like to know how DRV8711 detects Predriver Fault condtion.
-Do Gate drive & OCP detect Predriver Fault condtion using flowing current?
-Or, does Isense block detect Predriver Fault condtion using flowing current?
If Gate drive & OCP detect Predriver Fault condtion, could you let us how much the threshold for detection is?
And thenm there are description as follows;
8.1.2 Optional Series Gate Resistor
In high current or high voltage applications, the low side predriver fault may assert due to noise in the system. In
this application, TI recommends placing a 47 to 120-Ω resistor in series with the low side output and the gate of
the low side FET. TI also recommends setting the dead time to 850 ns when adding a series resistor.
->What does "assert due to noise in the system" indicate? If you have some concrete example and solution, could you share us?
As the background of this question, our customer's board occurs Predriver Fault condtion in case of startup sometimes.
So, they would like to judge whether it depends on the noise of Isense block or not.
Kind regards,
Hirotaka Matsumoto
