The overcurrent protection current we designed is 16.8A, but the chip is still unprotected when the load current reaches 18A. After that, I set rtrip to 5.6k on EVB (Replace the chip on EVB with tps548a28), that is, the overcurrent point is about 12A. At this time, the chip limits the current to 13A, but still does not protect the chip. What is the reason?
Figure 1 The current is limited to 13A Figure 2 Schematic diagram of EVB：R1=5k.R2=20k,RCS=5.6k