UNLESS OTHERWISE NOTED, this document contains PRODUCTION DATA.
Whenever the supply voltage VCCI crosses from below the falling threshold VVCCI_OFF to above the rising threshold VVCCI_ON, and whenever the supply voltage VDDx crosses from below the falling threshold VVDDx_OFF to above the rising threshold VVDDx_ON, there is a delay before the outputs begin responding to the inputs. For VCCI UVLO this delay is defined as tVCCI+ to OUT, and is typically 40 µs. For VDDx UVLO this delay is defined as tVDD+ to OUT, and is typically 23 µs. TI recommends allowing some margin before driving input signals, to ensure the driver VCCI and VDD bias supplies are fully activated. Figure 29 and Figure 30 show the power-up UVLO delay timing diagram for VCCI and VDD.
Whenever the supply voltage VCCI crosses below the falling threshold VVCCI_OFF, or VDDx crosses below the falling threshold VVDDx_OFF, the outputs stop responding to the inputs and are held low within 1 µs. This asymmetric delay is designed to ensure safe operation during VCCI or VDDx brownouts.
When VCCI goes away but VDDx is present, outputs are held low; when VDDx is gone, outputs are CLAMPED low through the active pull down feature. For more detailed UVLO feature description, please check session VDD, VCCI, and Under Voltage Lock Out (UVLO).