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

3.3V regulator circuit: LDO regulator output 3.3V for level conversion chip, Micro SD card supply

Level conversion circuit: Micro SD card to signal the direction of converts 3.3V, MicroSD card interface to control the direction of the MISO signal is also converted to 3.3V, general AVR microcontroller systems can read the signal

Specifications:

• Support Micro SD card, Micro SDHC card (high speed card)
• board level conversion circuit, namely the interface level for 5V or 3.3V
• power supply is 4.5V ~ 5.5V, 3.3V voltage regulator circuit board
• The communication interface is a standard SPI interface
• 5.4 M2 screw positioning holes for easy installation