I2S, or Inter-IC Sound, or Integrated Interchip Sound, is an electrical serial bus interface standard used for connecting digital audio devices together. It is most commonly used to carry PCM information between the CD transport and the DAC in a CD player. The I2S bus separates clock and data signals, resulting in a very low jitter connection. Jitter can cause distortion in a digital-to-analog converter. The bus consists of at least three lines:
1. Bit clock line
2. Word clock line (also called word select line)
3. And at least one multiplexed data line
You may also find the following lines:
1. Master clock (typical 256 x bitclk)
2. A multiplexed data line for upload
