ZHCSOF9B april 2022 – june 2023 TPS25981
PRODUCTION DATA
The TPS259814x devices respond to output overcurrent conditions during start-up by actively limiting the current. If the load current exceeds the set overcurrent threshold (ILIM) set by the ILM pin resistor (RILM), but stays lower than the short-circuit threshold (2 × ILIM), the current limit loop starts regulating the FET to actively limit the current to the set overcurrent threshold (ILIM). Equation 7 can be used to calculate the RILM value for a desired overcurrent threshold.
During active current limit, the output voltage drops, resulting in increased device power dissipation across the FET. If the device internal temperature (TJ) exceeds the thermal shutdown threshold (TSD), the FET is turned off. After the part shuts down due to TSD fault, it either stays latched off (TPS25981xL variants) or restarts automatically after a fixed delay (TPS25981xA variants). For more details on device response to overtemperature, see Overtemperature Protection (OTP).