Adafruit MicroSD Card Breakout Board

[boe729]

What are 12 and 15 connected to in the image above?

Thanks for any help!

[missdrew]

Nothing! They are spare level shifters.

[boe729]

So would the circuit function without them?

[LarryD]

No
because they are inside the same I.C. as the other 4 buffer drivers.

Cannot have one without the other.

[boe729]

Right so I am designing a pcb and wanted to incorporate a microsd card port how then do I connect the SD & MMC chip to those amplifiers? What pin are they connecting? Or are they just present but not in use?

[srnet]

What is the microcontroller you are using ?

[boe729]

I am using a MK20DX256VLH7 processor

[srnet]

@boe729

MK20DX256VLH7

Is that a 3.3V logic level processor ?

[boe729]

@srnet

Is that a 3.3V logic level processor ?

yes

[srnet]

So your providing a port to convert from 3.3V to 5V logic, so you can then connect a SD card adapter which then converts from 5V logic to 3.3V logic.

Why not connect direct, SD cards are 3.3V devices ?

[Alba_Salva]

Hi srnet.
How can I use a SD adapter directly?, I'm thinking about the idea of record data from an ESP32 microcontroller to a microSD card.

Thanks in advance and Happy New Year.

Alba.