AD768 as audio DAC

Surely flipping the MSB gets you complementary offset binary ? The issue as I see it is the sign bit used to signify positive and negative. Straight binary does not have one as it is only positive.
 
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I haven't worked it out with pencil and paper, just imagined it in my head. Which is fraught with opportunities for error 😀

Here is a useful document - https://www.ti.com/lit/an/sbaa042a/sbaa042a.pdf

Scrolling down to p8 of the above document it shows an MSB inverter is able to convert between BTC and BOB. Now BOB isn't exactly the code that the AD768 accepts, rather its USB (first coding example). Which differs only from BOB in that BOB is bipolar, otherwise the code mapping is the same. So I reckon the MSB inverter should work (famous last words!).
 
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Will the Toshiba 74AC04P work for inverting the MSB? Just want to double check before I order.

I take it these chips are industry standard and the [SIZE=-1]Logic IC Base Number: 7404 is what counts so all the plethora of 74**04 chips are all basically the same in functionality?
[/SIZE]
 
Updated schematic with inverted MSB.


Now I need to work out how to connect the clock and latch part of the I2S, I shall study the links Miro and Abraxalito posted.
 

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