MP1918 Grounding and Supply Strategy for GaN FET Application

Motor Drivers/Sensors
1

I am designing a power amplifier board using the MP1918 Gate Driver with GaN FETs for a DC motor phase-switching application. I have a few questions regarding the grounding and power supply configuration:

  1. AGND vs. PGND Separation: What is the technical reason for having separate Analog Ground (AGND) and Power Ground (PGND) pins on this device?

  2. Shorting the Grounds: In the datasheet’s typical application circuit, AGND and PGND are shorted together (often via a 0Ω resistor or a net tie). If they are eventually connected, why are they defined as separate grounds in the first place, and what is the best practice for connecting them in GaN environment?Single vs. Dual Supplies: Do VCC1 (referenced to AGND) and VCC2 (referenced to PGND) require independent power sources, or can they share the same rail with proper decoupling?

  3. Single vs. Dual Supplies: Do VCC1 (referenced to AGND) and VCC2 (referenced to PGND) require independent power sources, or can they share the same rail with proper decoupling?

I would appreciate your guidance on ensuring high noise immunity for this high-speed switching design.