Hi all, for a while i've been using both USB power and an external power supply for my MIDI Controllers, i use a standard 9v power supply on stage with a 5v regulator, the regulator and the USB Power supply connect to a pair of schottky diodes to switch between the sources and all is good.

Usually my controllers will draw between 150mA and 300mA depending on how many LEDs are on etc.

Now i'm using multiple OLEDs and more LEDs and I want to make sure I have more current than I need which my 9v power supply has (1.6A)

Both the regulator and USB feed a Teensy 3.6 VIN (i'm using a type B USB jack and the micro usb on the teensy is not used) then that 5v line is branch out to also feed displays and some neo pixels.

So I'm wondering a few things.

#1 if all the components together draw let's say 1 Amp does that mean that 1 Amp of current is flowing thru the Teensy itself as well or only the current the Teensy is pulling is going thru it the rest goes to the other traces on the PCB for the other components?

#2 is it safe to run the Teensy along side all the other components that may be drawing up to 1 Amp of current from the same power supply?

#3 on a PCB board that has 5v traces feeding different components is the total current being split evenly between traces or does current go to the component that is asking for it?


Now I should also note that this new controller i'm building already is up and running and drawing less than 250mA with all displays on, i don't have all the LEDs wired up yet so i'm expecting at least another 150mA if i were to have all LEDs on at the same time. The Schottky diodes are rated at 3Amps and all 5V traces on my PCB are thick enough to easily handle 1Amp

Right now im running it directly from one of my Mac's USB ports and no issues at all, however just because it's working well now doesn't mean that i may be missing something that i may regret later so i figured i'd ask about it here.

Thank you In advance!

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