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3.3V Pin
Moderators: adafruit_support_bill, adafruit

3.3V Pin

by rahatmaini on Thu Jan 03, 2013 12:55 am

So there is a 3.3V pin on the Uno. I am extremely confused as to why I need a logic level converter for an i2c device that requires 3.3v when I can just plug it in to the 3.3V pin instead of the 5V pin. PS I am connecting Nunchucky i2c breakout to Arduino Uno R3

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Re: 3.3V Pin

by adafruit_support_bill on Thu Jan 03, 2013 7:24 am

You can use the 3.3v pin to supply power to a 3.3v device. But a 3.3v device can be damaged if you try to communicate with it using 5v logic signals.

The level converter converts 5v logic signals to 3.3v logic signals. Our Bi-Directional logic converter also will convert 3.3v logic signals to 5v signals which is useful for I2C communication.
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