Kind of a simple question really. Does anyone see any reason why the AD5663 DAC wouldn't be suitable for reproducing audio? (http://www.analog.com/static/imported-files/data_sheets/AD5663.pdf). I've already stupidly bought an LTC2606 DAC just to realize that it's I2C interface was to slow for audio. This DAC uses an SPI interface up to 50MHz so I don't think it should be a problem but I want to know if you guys see any obvious reasons this won't work.
Also, assuming there are no problems with this DAC, which SPI mode should I use to write to it? By looking at the SPI timing diagrams in the datasheet it looks like data is shifted in on a falling edge of SCK. This means I should either use mode 1 or 2 if I'm reading the ATMEL datasheet correctly (Smart | Connected | Secure | Microchip Technology pg.195). But which one is it exactly? The SD card that I'm reading audio data from only works in mode 0 and 3 so I might have to switch modes every time I want to read a new page from the SD card, which would probably waste a lot of time
You did not say anything about an SD card. You can not have it on the same SPI bus as the D/A. This is because the SD card will have to be closed when you access the D/A and you can not access it fast enough if you are opening and closing it like this.
While it's true that I haven't tested how long it takes to open the SD card, read a page, and close it, (and now that I think about it it probably does take significantly longer than continuous reading) I can always use the second SPI port for the DAC (probably should have also mentioned I'm using an xmega :)) and read continuously off the SD card. In that case I'm also not limited to mode 0 or 3. Thanks for the heads up though. Luckily my second SPI port isn't occupied.