Part Number:TIDA-00366
UCC21520 Vdda is given at 16V using Bootstrap while the net VCC_U will also be at 16V w.r.to U_TOP_REF. but VCC_U is also used for giving supply for ADC using TL431 keeping VDD1 at 5V. Is this interpretation Correct.
It means 16V - 5V is dropped across the R72 820ohm resistor.