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Author Topic: SD card connection difficulty  (Read 365 times)
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 I want to connect a sd card to an arduino
Ive already connected it in the following way
         gnd                                  gnd
        MISO                                 12
          SCK                                 13
         3.3v                                   3.3v
         MOSI                                 11
          SSEL                                 10

by the way there is no onboard voltage regulator on the sd module
that is why I connected to 3.3v

Will the the SD card get damaged because im connecting 3.3v directly without any voltage divider circuit ??

can it ibe connected without use of resistors?
and how do I test the card?


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Arduino has 0-5V  outputs.
The card needs 0-3.3V on its SCK, Serial Data In, and Slave Select inputs.
So at a minimum you need a voltage divider on those inputs.
DC cards typically draw 200+ mA of current, while Arduino output only provides maybe 150mA.
So you really need a seperate 3.3V regulator as well.

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