ZHCSEF7G December 2014 – February 2019 TPS659037
PRODUCTION DATA.
VCC1 is the supply for the analog input voltage of the device. This pin requires a 10-µF decoupling capacitor.
Texas Instruments recommends to always power down the TPS659037 before removing power from VCC1. If the input voltage to the device is removed while the device is ACTIVE, the device will shut off when VCC1 reaches the VSYS_LO threshold. As mentioned in the Section 5.4.11 section, once VCC1 reaches VSYS_LO, there is about 180 us delay before all the output rails are disabled simultaneously.
There are two scenarios to consider in the system-level design in the event of unexpected loss of power.