I'm working on a project that uses this board I made and the Arduino Mega 2560, where the board will need to be powered by the Mega's +5V pin at certain times. A connector will be used to bridge the bus on the Mega (containing the +5V pin) with the board.
When the board is being powered by a DC supply (+12V regulated to +5V), and not the Arduino, I want to make sure that the Arduino +5V pin is protected from reverse voltage (seeing as the +5V pin is not an input.)
- Would a Schottky diode be the most ideal solution to make this work?
- I do not want to draw more than 500 mA of current, what part of the diode spec sheet would this apply to?
- +12V will be the largest voltage input for the project, so what range should I consider for the reverse voltage breakdown?
- Is it considered good practice to add a capacitor to ground on the cathode side of the diode? Or is that a specific design consideration (e.g. AC to DC rectified situation.)