I consider using a TxDAC AD9115 as a video DAC to produce 2 channels of NTSC composite video. The advantage of the TxDAC is it's high bandwidth and small PCB footprint, all the color modulation and sync will be done in FPGA. Does anyone has an experience with this combo? Are there any potential problems?
Can you use the ADV7390 instead?
ADV739x Design Support Files
I'd be worried with trying to get the color burst phasing correct with FPGA generation. NTSC uses phase information between the color burst and the color carrier to handle color.
Indeed, ADV7390 looks good, but I'm not sure it can generate two independent composite videos, it looks like three component (RGB/YUV) or one composite channel.
This is not a problem at all, I've done it with ADV7127 or ADV7123.