Is external memory required with the ADV7850 if you are not going to use the composite ADC?
For applications which do not use composite video, external memory is not required.
Frame Time Base correction for SD signals will not be available.
The following should be carried out
• SDRAM VDD supplies should be connected to DVDDIO
• SDRAM VREF should be connected to DGND
• DQ and DQS lines should be connected to ground through a 4k7 resistor
• All other memory pins can be left unconnected