SNVSBY7 March 2021 TPS92390
The FSET resistor missing or invalid for both BOOST_FSET and PWM_FSET is detected if any one of them is not assembled or not a valid value as requested during the initialization. TPS92390 defaults the switching frequency of boost to 400 kHz if BOOST_FSET resistor is missing or invalid, or PWM dimming frequency to 305 Hz if PWM_FSET resistor is missing or invalid. The FSET_STATUS fault bit is set in the BOOST_FAULT_STATUS register. The FSET resistor missing or invalid fault is not monitored after initialization, so that the TPS92390 device operates at the boost switching frequency and the PWM dimming frequency determined during initialization even though the FSET resistor is missing or invalid after initialization.