SLVSCO4D July 2015 – February 2019 TPS65917-Q1
All LDOs are integrated. They can be connected to the system supply, to an external buck boost SMPS, or to another preregulated voltage source. The output voltages of all LDOs can be selected, regardless of the LDO input voltage level, VIN. No hardware protection is available to prevent software from selecting an improper output voltage if the VIN minimum level is lower than the total DC-output voltage (TDCOV(LDOx)) plus the dropout voltage ( DV(LDOx)). In such conditions, the output voltage is lower and nearly equal to the input supply. The output voltage of the regulator cannot be modified while the LDO is enabled from one voltage range (0.9 to 2.1 V) to the other voltage range (2.2 to 3.3 V). The regulator must be restarted in these cases. If an LDO is not needed, the external components do not need to be mounted. The TPS65917-Q1 device is not damaged by such configuration. The other functions do not depend on the unused LDOs and work properly.