Logic Levels

Contributors: bri_huang
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Arduino Logic Levels

Looking at the datasheet for the ATMega328 (the primary microcontroller behind the Arduino UNO and the Sparkfun Redboard), you might notice that the voltage levels are slightly different.

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The Arduino is built on a slightly more robust platform. The most noticable difference is that the invalid region of voltages is only between 1.5 V and 3.0 V. The noise margin is greater on the Arduino and it has a higher threshold for a LOW signal. This makes building interfaces and working with other hardware much simpler.