Logical pinout · physical placement not verified

3V
3.3 V power input for the microSD card breakout; Adafruit warns that 5 V or VBAT will damage the card.
Type · PowerVoltage · 3.3V only
GND
Common ground for power and logic.
Type · GroundVoltage · 0V
DET
Card-detect signal; connected to GND internally when no card is inserted and pulled up to 3V through 4.7 kΩ when a card is inserted.
Type · GPIOVoltage · 3V logic
CLKSCK
SPI clock input to the SD card.
Type · SPIVoltage · 3V logic
SOMISO
SPI serial data out from the SD card to the microcontroller.
Type · SPIVoltage · 3V logic
SIMOSI
SPI serial data input from the microcontroller to the SD card.
Type · SPIVoltage · 3V logic only
CS
SPI chip-select input; pull low to start an SPI transaction.
Type · SPIVoltage · 3V logic only
CMD
SDIO bidirectional command/information signal between microcontroller and SD card.
Type · GPIOVoltage · 3V logic
D0
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D0.
Type · GPIOVoltage · 3V logic
D1
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D1.
Type · GPIOVoltage · 3V logic
DAT2
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as DAT2.
Type · GPIOVoltage · 3V logic
D3
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D3.
Type · GPIOVoltage · 3V logic

Pin	Type	Function	Voltage
3V	Power	3.3 V power input for the microSD card breakout; Adafruit warns that 5 V or VBAT will damage the card.	3.3V only
GND	Ground	Common ground for power and logic.	0V
DET	GPIO	Card-detect signal; connected to GND internally when no card is inserted and pulled up to 3V through 4.7 kΩ when a card is inserted.	3V logic
CLKSCK	SPI	SPI clock input to the SD card.	3V logic
SOMISO	SPI	SPI serial data out from the SD card to the microcontroller.	3V logic
SIMOSI	SPI	SPI serial data input from the microcontroller to the SD card.	3V logic only
CS	SPI	SPI chip-select input; pull low to start an SPI transaction.	3V logic only
CMD	GPIO	SDIO bidirectional command/information signal between microcontroller and SD card.	3V logic
D0	GPIO	SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D0.	3V logic
D1	GPIO	SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D1.	3V logic
DAT2	GPIO	SDIO bidirectional data line; Adafruit identifies the silkscreen legend as DAT2.	3V logic
D3	GPIO	SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D3.	3V logic

Logical pinout · physical placement not verified

Pin details

12 connections

3V
3.3 V power input for the microSD card breakout; Adafruit warns that 5 V or VBAT will damage the card.
PowerVoltage · 3.3V only
GND
Common ground for power and logic.
GroundVoltage · 0V
DET
Card-detect signal; connected to GND internally when no card is inserted and pulled up to 3V through 4.7 kΩ when a card is inserted.
GPIOVoltage · 3V logic
CLKSCK
SPI clock input to the SD card.
SPIVoltage · 3V logic
SOMISO
SPI serial data out from the SD card to the microcontroller.
SPIVoltage · 3V logic
SIMOSI
SPI serial data input from the microcontroller to the SD card.
SPIVoltage · 3V logic only
CS
SPI chip-select input; pull low to start an SPI transaction.
SPIVoltage · 3V logic only
CMD
SDIO bidirectional command/information signal between microcontroller and SD card.
GPIOVoltage · 3V logic
D0
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D0.
GPIOVoltage · 3V logic
D1
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D1.
GPIOVoltage · 3V logic
DAT2
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as DAT2.
GPIOVoltage · 3V logic
D3
SDIO bidirectional data line; Adafruit identifies the silkscreen legend as D3.
GPIOVoltage · 3V logic

Memory

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