So when using the Arduino UNO and powering it externally via the barrel jack with a 9V 1.5 A source, can I apply a large current load to the 5V pin (such as 800 mA) without seeing any spikes in current on the 3.3V pin? Essentially, I would be powering a wireless transceiver such as the Longruner NRF24L01 off of the 3.3V pin, and then I would apply a larger load of resistors to the 5V pin (for a university test) that would likely draw around 800 - 1000 mA. Before conducting this test, I wanted to be sure that I wouldn't damage the transceiver connected to the 3.3V pin, as I am aware that the 3.3V pin feeds off of the 5V rail. A large current surge on the 5V pin wouldn't also affect the 3.3V pin right?
Thank you for your time in answering this question.