The module (MicroSD Card Adapter) is a Micro SD card reader module, and the SPI interface via the file system driver, microcontroller system to complete the MicroSD card read and write files.

Arduino users can directly use the Arduino IDE comes with an SD card to complete the library card initialization and read-write.

Module features are as follows:

• Support Micro SD Card (<=2G), Micro SDHC card (<=32G) (high-speed card)
  
• The level conversion circuit board that can interface level is 5V or 3.3V
• Power supply is 4.5V ~ 5.5V, 3.3V voltage regulator circuit board
• Communication interface is a standard SPI interface
• 4 M2 screw positioning holes for easy installation
• Size: 4.1 x 2.4cm

Control Interface:

A total of six pins (GND, VCC, MISO, MOSI, SCK, CS), GND to ground, VCC is the power supply, MISO, MOSI, SCK is the SPI bus, CS is the chip select signal pin

3.3V regulator circuit:

LDO regulator output 3.3V as level converter chip, Micro SD card supply

Level conversion circuit:

Micro SD card into the direction of signals into 3.3V, MicroSD card toward the direction of the control interface MISO signal is also converted to 3.3V, general AVR microcontroller system can read the signal