I have an application where multiple times I need to come up with 10 dac channels who's outputs are 0 to -2.5V below a programmable voltage rail. The programmable voltage rail goes from -2V to +3V. I have clean +/- 10.5V supplies available as well.
I can do this with many op-amps, but there must be a cleaner way using clever DACs.
I'm looking at the AMC7832 part (I could use the ADC as well). The thought would be to power the part between my programmable voltage rail and +5V above that (which I'd get from a linear regulator from the +10.5V rail--it only needs a small amount of current). I can easily level-shift the three-wire interface. However, I don't believe I have enough supply to cover the range given that it wants to put out -10V to 0V (relative to my supply) in its inverted output mode. Perhaps there's some way to reduce this?
Any other thoughts on ways to create MANY negative DAC outputs relative to floating supply level?
Thanks all, Tom.