SNLS543 August 2018 DS90UH949A-Q1
When ambient temperature around the DS90UH949A-Q1 changes by more than 40°C, the frequency detection logic in the device can RESET the FPD-Link III PLL even though the input PCLK has not changed. This behavior may result in a loss of lock in the Deserializer and flicker on the system display.
The following programming sequence is required for all systems. This should be written after the user register configuration of the DS90UH949A-Q1 and downstream Deserializer configuration.