SCAS892C February 2010 – December 2016 CDCE937-Q1 , CDCEL937-Q1
PRODUCTION DATA.
There is no restriction on the power-up sequence. In case VDDOUT is applied first, TI recommends grounding VDD. In case VDDOUT is powered while VDD is floating, there is a risk of high current flowing on the VDDOUT pins.
The device has a power-up control that is connected to the 1.8-V supply. This keeps the whole device disabled until the 1.8-V supply reaches a sufficient voltage level. Then the device switches on all internal components, including the outputs. If a 3.3-V VDDOUT is available before the 1.8-V, the outputs stay disabled until the 1.8-V supply has reached a certain level.