I2S vs I2C problem please help!

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Hi all, i am new to this type of electronic systems and i wish to get some facts about these 2 protocos. Are the I2C and I2S compatabile? If I have a system which needs an ADC and DAC will it make a difference if I use the DAC with I2S compatabile and the ADC I2C compatabile?

Thanks!
 
Well, perhaps you should start by reading up on the two: I2S and I2C.

Basically one of them is specifically designed for sending audio streams over short distances inside an appliance (I2S) and the other is a protocol for communication between several units connected to one common bus (I2C). Thus it can quite simply be concluded that they are not compatible per se.

I would also be very surprised if any IC, be it a DAC or ADC, uses I2C for audio. I don't even think that's possible since, for example, I2S is at least 3 wires where I2C is only two.
 
First of all thanks, and i have another problem i will use a PIC32 to connect these Adc and Dac which only have pins for I2C and SPI this means that i cant use the I2S. lets say i use the I2C for the Adc will this mean that i have to choose a DAC which also interfaces data in I2C? or I can use a Dac with SPI interface? In other words i have to choose an ADC and a DAC which both uses for example I2C? Or i can vary the interface and still i will not have any problems?
 
You need to read the data sheets more carefully, I2C/SPI would normally be for control path of those devices, and many audio ICs actually use neither, there will be an audio bus which is usually compatible with I2S and a number of other common formats.

Why don't you share the actual part numbers of the parts you want to use and provide links to their data sheets?

You can use SPI or I2C or GPIO on the PIC to control the audio devices you intend to use.

Any audio bus will consist of at minimum DATA, LR clock and BIT clock, often a system clock will be included. Data can be standard I2S, left or right justified, 16, 24, or 32 bit, etc. This is simplistic and does not tell the whole story, dig further, Google is your friend.
 
I²C (pronounced I-squared-C) is a serial data protocol, and in the case of an ADC as the OP mentioned, would be used to get the digital audio data out of the ADC and into something like a PC.
I2S is a data protocol used exclusively for audio, usually DAC input, and is not compatible with I²C.

(Kevin, I think you meant I2S on the last line of your last post 🙂)
 
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I²C (pronounced I-squared-C) is a serial data protocol, and in the case of an ADC as the OP mentioned, would be used to get the digital audio data out of the ADC and into something like a PC.
I2S is a data protocol used exclusively for audio, usually DAC input, and is not compatible with I²C.

(Kevin, I think you meant I2S on the last line of your last post 🙂)

Indeed I meant I2S..

I2C uFM (2012 and not widely deployed) is fast enough for two channels of serial audio, but I'm not aware of any devices that use it for this purpose, the next fastest is I2C FM at 1MHz, all of the I2C I work with runs at a paltry 400kHz which is not fast enough for audio of reasonable quality. The protocol is commonly used with slow multiplexed ADCs and DACs where the signals measured are DC or low frequency. A good example would be the LTC2309 12 bit SAR ADC..
 
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