KUUK

Building a minimum168|8 arduino for battery use:

If we leave out the USB and power regulation circuitry from the official arduino schematics we have a quite simple setup that can still run your programs provided you power it from a suited source at 5V.

The reason for the 5V minimum is the external crystal @ 16Mhz. The datasheet for the atmega168 tells us at that the maximum frequency for the processor is dependant on your voltage source (page 305). So you need at least 4,5V to run it at 16Mhz in the “Safe Operating Area”. We don’t want to care why that is but conclude that if we want to run it at say 3,3 volts, we have to accept a slower performance and do some work.

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Though it seems relatively widespread to compare the invisible phenomenon of electrical current with the flow of water, most models stop where it gets complicated. To be honest, when i started tinkering with the first electronic circuits, i always imagined wires as pipes and current as water flowing through them. The problem was that i didn’t trust this image myself.

Current is just one parameter in a circuit, but then there you have voltage, resistance, capacitance, impedance, you name them.

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