SNLS543 August 2018 DS90UH949A-Q1
The Serializer has a PDB input pin to ENABLE or POWER DOWN the device. This pin may be controlled by an external device, or through VDDIO, where VDDIO = 1.71 V to 1.89 V. To save power, disable the link when the display is not required (PDB = LOW). Ensure that this pin is not driven HIGH before all power supplies have reached final levels. When PDB is driven low, ensure that the pin is driven to 0 V for at least 3 ms before releasing or driving high. In the case where PDB is pulled up to VDDIO directly, a 10-kΩ pullup resistor and a >10-µF capacitor to ground are required (see Power Up Requirements and PDB Pin).
Toggling PDB low will POWER DOWN the device and RESET all control registers to default. During this time, PDB must be held low for a minimum of 3 ms before going high again.