Alright, time to revive something..
Here's what I was tinkering lately about, repeating infamous Linear AN86, as it looks to me that no one actually built it before.
But since I went with modern parts, hopefully with better end result, my schematics which I'd like to present is not direct copy.
Both DACs: 18-bit Linear LTC2756 (about same topology as LTC1599, as far I can see).
Feedback ADC: 24-bit LTC2442
Reference: LTZ1000 direct input +7.2 for DACs, Divided (resistors) and inverted (LTC1043) to 2.5000/-2.5000V for ADC.
Digital domain: ALTERA MAXII CPLD
Output stage: That part later, currently task is to build stable -14...+14V DAC using this module.
There is also dual DAC available from Linear, LTC2758, but it's price is more than double of 2756's.
I have DACs and ADC already on my table.
Please, take a look on schematics, and let me know where I failed to understand analog magic
Hopefully we can correct mistakes and I could make few PCBs to try it on. Best contributors can count on PCB (no parts, tho) too