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What is I2S used for?
I2S (Inter-IC Sound), is an electrical serial bus interface standard used for connecting digital audio devices together. It is used to communicate PCM audio data between integrated circuits in an electronic device.
What is the difference between I2C and I2S?
I2C is 2 wire protocol and I2S is 3 wire protocol. I2C supports clock stretching and I2S does not have clock stretching. I2C has an extra overhead start and stop bits and I2S does not have any start and stop bits. I2C has a pullup resistor requirement.
What kind of data does an I2S receiver send?
I2S sends a stream of stereo audio data. For each audio sample there is a left channel and a right channel value. The values can be any number of bits, although 16, 20, 24, and 32 bit values are the most common. The I2S Bus Specification provides a really good overview of the protocol and you should download and peruse that link now.
What are the characteristics of an I2S signal?
The following lists identify salient characteristics of the three I2S signals. Digital values are transmitted MSb first. Transmitter and receiver do not need to have an agreed-upon word length; the transmitter sends what it has, and the receiver takes what it can use. New data bits can be clocked out on the rising or falling edge of the clock.
How is data driven on the I2S interface?
Diagram taken from the I2S specification, first published by Philips Semiconductors in 1986 and revised in 1996. Data is driven on the SD line, the state of the WS line corresponds to the audio channel (right or left) that is currently being transmitted, and the clock line carries the serial clock.
How is the I2S protocol used in audio?
The I2S protocol is a common standard used to send audio data. It is a serial protocol very similar to SPI, but it is a streaming protocol. That means it is always transmitting data. I2S sends a stream of stereo audio data.