This FAQ applies to the ADV7180, ADV7181C/D, ADV7182, ADV7280, ADV7280-M, ADV7281, ADV7281-M, ADV7281-MA, ADV7282, ADV7282-M and ADV7283 models.
The unused analog input pins (Ain X) of analog devices video decoders can be :
1) left floating
2) connected via a resistor to ground.
2) connected directly to ground.