SLUSF13 august 2023 UCC15240-Q1
PRODUCTION DATA
UCC15240-Q1 can take wide input voltage range, from 21 V to 27 V. When the input voltage becomes too low, the output either cannot be regulated due to the transformer turns ratio limitation, or the converter operates with too much current stress. Either way, the converter must shut down to protect the system.
The UCC15240-Q1 enters input undervoltage lockout when VVIN voltage becomes lower than the UVLO threshold VVIN_UVLOP_FALLING. In UVLO mode, the converter stops switching. After VIN pin voltage becomes lower than the VIN analog undervoltage lockout falling threshold VVIN_VULOP_FALLING , UCC15240-Q1 resets all the protections. After that, after the VVIN voltage becomes above the UVLO threshold VVIN_UVLOP_RISING, the converter is enabled. Depending on the ENA pin voltage, the converter can start switching, go through the soft-start process, or in the disable mode, waiting for ENA pin voltage becomes high.