Agreed with Audioengr, Slappy & Sean.
In general, semiconductor manuf. add I.C.s to their portfolio all the time so that their product offerings always provide the best profit margin to them. I just looked @ Burr-Brown's website. I don't see the 1790 DAC there (in the Audio D to A section) but I see the 1791 DAC. Maybe the 1790 is too "old"?? However, if we compare the 1791, 1792 & 1796 then we see that the 1791 offers the lowest SNR(=113dB) at the lowest power consumption(=90mW). The 1796 seems to be placed right in the middle where it offers better SNR than the 1791 (but not as good as the 1796) at a modest power consumption increase over the 1791 (but not as much as the 1796). Looks like they offer a low power version (1791), a medium power version (1792) & a high power version (1796). I'm guessing from my experience as no further data is available that the 1796 is fabricated in some later technology than the 1792 & 1791 to realize the benefits of better SNR at a modest power increase. Semiconductor manuf. generally do this - migrate their portfolio gradually to the better technology 'cuz they can reduce die size hence realize a better profit margin.
All this does *not* necessarily mean better sound. The designer of the audio gear must know how to use the part expertly to squeeze every ounce of perf. from it. I know this from my experience wherein working w/ the customer on how to use our parts is a vital part of our relationship w/ them. 99% of the time, if we do not interfer, the customer totally botches the implementation of our part in their final product! Not surprising as our ICs are complicated but all too often we assume that if we put the part on the technology shelf someone will come & pick it up & use it correctly! Wrong!
Can't say whether or not there is an applications group in Burr-Brown that the audio manuf consults when they use their part. However, implementation on the audio manuf's part is key to making a good DAC design sound excellent.
Long answer/explanation to Audioengr's succinct & correct (IMHO) answer.
In general, semiconductor manuf. add I.C.s to their portfolio all the time so that their product offerings always provide the best profit margin to them. I just looked @ Burr-Brown's website. I don't see the 1790 DAC there (in the Audio D to A section) but I see the 1791 DAC. Maybe the 1790 is too "old"?? However, if we compare the 1791, 1792 & 1796 then we see that the 1791 offers the lowest SNR(=113dB) at the lowest power consumption(=90mW). The 1796 seems to be placed right in the middle where it offers better SNR than the 1791 (but not as good as the 1796) at a modest power consumption increase over the 1791 (but not as much as the 1796). Looks like they offer a low power version (1791), a medium power version (1792) & a high power version (1796). I'm guessing from my experience as no further data is available that the 1796 is fabricated in some later technology than the 1792 & 1791 to realize the benefits of better SNR at a modest power increase. Semiconductor manuf. generally do this - migrate their portfolio gradually to the better technology 'cuz they can reduce die size hence realize a better profit margin.
All this does *not* necessarily mean better sound. The designer of the audio gear must know how to use the part expertly to squeeze every ounce of perf. from it. I know this from my experience wherein working w/ the customer on how to use our parts is a vital part of our relationship w/ them. 99% of the time, if we do not interfer, the customer totally botches the implementation of our part in their final product! Not surprising as our ICs are complicated but all too often we assume that if we put the part on the technology shelf someone will come & pick it up & use it correctly! Wrong!
Can't say whether or not there is an applications group in Burr-Brown that the audio manuf consults when they use their part. However, implementation on the audio manuf's part is key to making a good DAC design sound excellent.
Long answer/explanation to Audioengr's succinct & correct (IMHO) answer.