“Audio” DAC vs DAC and I2S questions

Projects Networking, Protocols, and Devices
1

Greetings,

I am working on a project where I need to read a value (24 bit) from a senor and output the sensor data as an analog value to pass to a data acquisition system.
I have been able to get this to work on a MCP 4911, but I am limited to 12 bits and I really need to be over 16. So my search on Digikey lead me to the PCM1780 and the PCM1681. I started with the PCM 1780, and I have a few questions that should be simple.

  1. What is a, Audio Digital-to-Analog Converter? By this I mean, is an audio DAC different than a normal DAC? Will I be able to feed in a 16 bit binary and obtain a steady voltage at out end?
  2. The 1780 while listed as a SPI on Digikey the chip seems to be an I2S format chip. Can I use my Uno to interface with this? (I think this is a NO).
  3. The 1780 has a SCK line, called the system clock. Do I have to use this if I just want to use the chip as a normal DAC? (This is assuming I can use this as a DAC).
  4. Why is this chip so cheap? Every other 24 bit DAC on Digikey is $10 +, and this one is less than $2.00. I just found this odd.

Thanks in advance,

Austin.