I am working on a circuit connected to computer with FTDI FT232RL. The circuit have got some op-amps and one MCU. Total power consumption (including FTDI chip) is near by 0.4 Watts. My op-amps need well regulated 5V power (single supply). Here comes the time to design power supply. USB Vcc pin is connected to the FT232RL Vcc and MCU's Vcc. The question is this how i should use USB's Vcc pin?
First connecting USB Vcc to LDO regulator IC like AMS1117 and powering both FTDI IC and MCU + Op-amps with AMS1117's regulated output is good?
USB Vcc-->AMS1117-->FTDI chip+MCU+Op-amps
Or connecting USB Vcc to FTDI Vcc and a regulator IC on the MCU +Op-amps is better?
USB Vcc-->FTDI chip-->AMS1117-->MCU+Op-amps