I will drive the DAC AD5790 over an SPI-Interface which is powered by 1V8!
Actually, I've plan to powered the device with 1V8 on Pin IOVCC and 3V3 on Pin VCC.
(VDD and VSS is driven by +7V5/-7V5)
Can is DAC working fine with this power supply configuration. In the datasheet is this range available.