ZHCSI09S June 2010 – August 2018 TPS65911
The TRIP pin is used to set the VDDCtrl current limit. The load current is sensed by measuring the voltage over the low-side FET and comparing it to the voltage at the TRIP pin, VTRIP, with an 8:1 ratio. If the low-side FET is greater than an eighth of VTRIP, the VDDCtrl rail shuts down.
The TRIP resistor then adjusts the range of the VDDCtrl load current monitoring. Use Equation 3 to calculate the value of the TRIP resistor (RTRIP) for the application and selected external FETs.