5v SD Card Module

Hi All,

I have an SD Card Module, which works great on my Uno. I have the SD Fat ported library, but the demo fails immediately on the libraries begin function (error code 10)

Any how I re checked my hardware on the Uno and it got me thinking, the difference is that the Uno was using the 5v output and the Photon has a 3.3v.

I connected ground on the Uno and Photon, and used the Uno 5v Pin and guess what, it worked.

Now my electronics knowledge is very small, so my question is, what do i need to do to get this to work with my Photon?

Any help would be great



The Vin pin on the Photon can source 5V when connected to USB

But SD cards are natively running on 3.3V, so if you had a way to bypass the regulator on the module (and level shifters if present) you should be good with 3V3.

HI Thanks for the reply, that worked a treat.

As an aside, I want to use this in a wearable situation, and was going to use a lipo, but the lipo batteries tend to say 3.7v, what do you think?

again thanks for the reply.

You could use a buck-converter to boost 3.7V to 5V, but as I said SD is 3.3V so just get an SD card holder without the extra burden of going up to 5V to just regulate it down to 3.3V again.

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That’s a fair point re the 3.3v sd card reader.