Even average soundcards sport a 24bit DAC. However they're designed for a dynamic output so tend to have quite crap DC precision. What matters to a soundcard is producing a precise waveform, not a precise DC voltage.
This part is designed for DC level setting, ie a programmable reference voltage. Typically it won't change that often (compared to a soundcard), but it needs to be precise.
For example, compare the AD5791[1], a 20-bit DAC with 1LSB DC accuracy costing $40 in 1000 qty, to a 24bit audio DAC like the AD1955[2] costing about $7. The datasheet for the audio DAC doesn't even specify the DC precision, only a 6% gain error from the output buffer.
On the other hand if all you care about is DC precision you can use a very simple, though not necessarily easy, circuit. You need a stable voltage derived from a stable voltage reference, and a stable clock to PWM that stable voltage. Then you "just" low-pass filter the heck out of the PWM to get an adjustable DC value, and calibrate out any offsets. I've seen this used in adjustable voltage standards (forget which) and the venerable Fluke 5700A Multifunction Calibrator[0].
Even average soundcards sport a 24bit DAC. However they're designed for a dynamic output so tend to have quite crap DC precision. What matters to a soundcard is producing a precise waveform, not a precise DC voltage.
This part is designed for DC level setting, ie a programmable reference voltage. Typically it won't change that often (compared to a soundcard), but it needs to be precise.
For example, compare the AD5791[1], a 20-bit DAC with 1LSB DC accuracy costing $40 in 1000 qty, to a 24bit audio DAC like the AD1955[2] costing about $7. The datasheet for the audio DAC doesn't even specify the DC precision, only a 6% gain error from the output buffer.
[1]: https://www.analog.com/en/products/ad5791.html
[2]: https://www.analog.com/en/products/ad1955.html