I am working with ADE 7953 in an application where I need to measure single phase current and voltage. I am in the phase of designing the PCB for ADE 7953 and would like to ask some basic questions related to the design. My application consists of Atmel SAM4S uC which operates at 3.3V for this I will need a power supply which will also be used for powering up ADE 7953. I would like to ask, whether I need an isolated power supply for ADE 7953 or can I use the same one that I will use for uC? Also if I use the same supply would it be okay to use the same GND for both? Is there an isolation inside ADE 7953 which separates the high voltage AC measurement side of the device from the digital outputs and power supply side? I have gone through the Application Note AN-639 but still have these doubts. If someone could help me in this matter it would be much appreciated.