This design have 2 PSU’s. One is the ANS1117 that takes up to 12/16V input and 0.5A. The second is the DC/DC on DRV10983 that delivers 100mA and allow the Circuit to be used up to 28V. I have connected both for now. The datasheet for MAX3485 indicate up to 200mA, but my own measuring indicate MCU + RS485 will use < 20mA, so lets try. I will simply avoid mounting AMS1117 and remove it on the NeXT layout if it Works.