[sdiy] Filter cut off DAC

[Neil Johnson]

Paula wrote:
> I somehow suspect that these days a 12bit DAC, even a reasonably priced one,
> would have a better INL and DNL than the DAC from 1981.

DAC technology hasn't really changed much over the decades.  What has
changed is the price and silicon performance (i.e., same performance
on a smaller geometry, so price goes down/profit up).

Here's a "16-bit" DAC:
https://www.maximintegrated.com/en/products/analog/data-converters/digital-to-analog-converters/MAX5541.html

The INL is 16, meaning the bottom four bits are noise.  So really it's
a 12-bit DAC (actually quite a good one, INL < 1 bit) sold as a 16-bit
DAC.  Marketing.  Yay.

Some DAC families are actually the same die, they just test them on
the ATE and sell them as 12/13/14/15/16-bit converters based on how
well they perform.  And remember, the datasheet specs are worst-case,
so you might well get a 14-bit DAC sold as a 12-bit DAC if the 12-bit
bin is looking a bit empty.

Neil
-- 
http://www.njohnson.co.uk