DRV8872-Q1: nFAULT timing under OCP and TSD

Hi Yoshida-san,

Tomoaki Yoshida said:

1. OCP

If the output current exceeds Iocp for 2 us (tOCP), the driver should turn off, but will there be delay before nFAULT goes high?

After 3ms(tRECOVERY), when it will automatically restart, is nFAULT also returned to Low?

Please note nFAULT goes low to signal a fault, and high to signal the device is operating properly.

Please refer to Figure 13 of the datasheet. This is the end of one OCP cycle (~3ms after the OCP event) and the beginning of the next. There is very little delay before nFAULT goes low to signal an OCP.

Please note nFAULT high prior to the outputs re-enabling. 

Tomoaki Yoshida said:

2. TSH

Is there a delay in the output change of nFAULT as in the above case?

Is there any reference data to know the time it takes for the device to cool down after it stops at TSD?

For example, when ambient temperature is 125 ° C on the evaluation board, it took approximately how long it took to return.

In OCP, the automatic recovery is 3 ms, so I'd like to know about the approximate level, like a few usec or msec.

There is a slight delay (~10us). There is no reference data for the time to cool down. This is dependent on the ambient temperature and the board layout. TSH recovery is usually in the tens to hundreds of ms.