PC power via USB versus external power supply

Hello All,

I am just starting out. I would like to know the best approach for testing and development in regards to power supplies. I understand that the Atmega 328P is powered via my usbasp programmer derived from USB power from computer. However, I will eventually need more current that the USB can deliver. Yet I wish to test on a breadboard. What is the best approach to program,test and debug and ensure my power requirements are meet. Thanks

I will eventually need more current that the USB can deliver.

Assuming the other circuitry (whatever’s consuming the current) runs off 5V, I recommend a separate 5V supply (connected to the 5V pin).

There also limits to the amount of current the Arduino’s on-board 5V regulator can supply, so don’t use a wall-wart into the barrel connector to supply that additional current.

If the external circuitry uses a higher voltage, you can connect that higher voltage into Vin or into the barrel connector, and use the on-board regulator for the Arduino only.

You can also get power modules that you can connect to your breadboard (for example duinotech dc-dc adjustable stepdown module - Jaycar electronics which you can hook any higher DC voltage up to it and dial in a lower voltage.

There are also breadboard kits that come with a power supply such as solderless breadboard with power supply - jaycar electronics which you can connect a wallwort to. This is handy while you are rigging and testing before final build

Where I live the only local retailer is Jaycar electronics.

Project I am building at the moment is portable and needsboth 5v and 6v so I plan on using 12v batteries/plugpack and will be using the above mentioned power module for the 5v and a regulater for the 6v (running off the same 12v supply).