I am designing a device and I'm confused on calculating my total amperage required.
I have designed this device to have 3 main circuits in parallel that all take 5 V from the same power source:
- First is some LEDs,
- second is a microcontroller circuit to control those LEDs, and
- third is a few USB charging ports for phones etc.
I've estimated I will need at most 600 mA for the LEDs, the microcontroller circuit will take next to nothing but I am using 200 mA as the max current it will pull, and the charging devices I think will at most need 12A. (I have 4 in parallel
that take 0-3A input, is 12A correct?)
So am I correct in thinking this will need 13A max?
Best Answer
You are correct on the math, however designing for the max current could be a more expensive design than necessary. For example, if you are not going to have more than two devices charging, and each actually needs 2 amps, then you just need a 5 amp supply, which would be a lot cheaper (and smaller) than the 13 amp supply.