Hi, I want to know how I can connect an external reference voltage for my STM32F407. The internal reference voltage is at 3.3 volts and my input goes beyond that voltage to about 5 volts. When I feed the 5 volts as input to my microcontroller, I get a wrong reading. So, I want to change the reference voltage to 5 volts using an external source. How do I do that?