I2S -> SPDIF conversion

SteveCarr

Member
2008-02-07 12:36 am
I2S -> SPDIF conversion

Hi there,

I would like to build a combined microphone pre-amp and ADC to output to SPDIF.

I can find lots of nice ADC chips but they all output I2S and not SPDIF so I need a converter to go from I2S to SPDIF.

Does anybody have any idea what the part number is and where I could get one from? (I am in the UK).

Also any advice on my project would be welcome.

Regards

Steve
 

SteveCarr

Member
2008-02-07 12:36 am
Many thanks for the fast replies I am very appreciative. I will have a look at all of the suggestions you have made.

I guess a low noise that the pre-amp on its own is not so hard to make but I guess it gets harder when it will be fed from the same battery as the didgital part of the circuit which has potential to introduce noise.

Any further advice about this and the pre-amp part would be appreciated.

Many thanks

Steve
 

error401

Member
2007-03-24 7:54 am
It shouldn't be too hard. Here are some ideas you should follow for an I2S ADC anyway.

- use ground planes, on the top layer, with a separate plane for digital and analog sections, connected at a single point
- use separate regulators for analog and digital supplies
- use ample supply decoupling
- make sure your layout doesn't create any current loops that could pick up interference

These recommendations are probably in your ADC's datasheet anyway.
 
There is also the Cirrus CS8406 and CS8427. A transmitter and a receiver. They also make the CS8420 which is a transceiver with built in SRC. I've used the CS8420 and it works very well but it has a weird property where it can not transmit unless it has first received something with which to jump start the clocks. I'm ot sure if they have fixed this since I used the part a few years back.

http://www.cirrus.com/en/products/pro/techs/T4.html