QI proposed AD5556 DAC to be used for two different functions:
1. Programmable Voltage Generation between 0V and Vref
2. Programmable Current, always positive current.
The designed board will only have positive voltage sources.
Can AD5556 be used like described above without the need of opamp powered at
AI am afraid that there is no possible way to obtain a +Vout from a +Vin without
the use of negative voltage on the external required opamps.
Iout and GND terminals need to be both maintained at the same potential, and
for that to happen an op amp is used at the output of the MDAC.
The MDACs transfer function is: Vout= -[Vref (D)]/(2n-1), a negative output
voltage that makes the op amp to be powered by a negative voltage. A second op
amp can be used to offer a positive output voltage but you still need to
provide that negative voltage.