My customer is having an issue with the TI DRV8432 current limit. He is operating the device in parallel bridge mode and has the current limit resistor set at 100K, 2.8A nominal current limit for each H-Bridge. We are assuming the limit will be at 5.6A (2 x 2.8A) typical since I’m in parallel mode. Its tripping significantly below that - <2A. We put a 100pF across the 100K and it increased the limit to about 3.4A.
There is no documentation on the overcurrent pin – We assume it’s a current source driving the external resistor and sending the resultant voltage to internal comparators on the bridges. Therefore, a cap should be OK, but I’d like to know for sure. Can you confirm our assumtions about the current source+resistor+cap and offer any reason for the discrepancy in current limit threshold? Thanks
