In industrial application isolation is a must, so i have to isolate SPI and power.
Is it possible to power AD5755 from isolated 5V without additional isolated +12V Avdd. I have tried with unconnected AVdd without success. Next try was with Boost Voltage connected to Avdd (DCDC enabled in software), again without success. I have also connect VrefIn to 5V and than DC/DC converter started but i got different voltage at 4 different channels. 19V, 19V, 12V, 19V.