The Micro SD Card Reader Module is a compact storage interface module that allows microcontrollers to read from and write to micro SD cards. It is commonly used for data logging, file storage, configuration saving, and multimedia applications in embedded systems and IoT projects.
Core Module Specifications
• Supported Memory Type: Micro SD / TF card
• Supported File System: FAT16 / FAT32
• Communication Protocol: SPI
• Card Capacity Support: Up to 32 GB (module and firmware dependent)
Electrical & Interface
• Operating Voltage: 3.3 V – 5 V
• Onboard Regulator: Yes (for 5 V compatibility)
• Logic Level: 3.3 V (level shifting on module)
• Interface Pins: CS, MOSI, MISO, SCK
• Additional Pins: VCC, GND

Performance Characteristics
• Read Speed: Depends on SD card class and SPI clock
• Write Speed: Depends on SD card class and file size
• Data Integrity: Reliable storage with proper power supply
• Hot Swap Support: Not recommended during active operation
Physical Characteristics
• Module Type: PCB-mounted SD card slot
• Form Factor: Compact and lightweight
• Card Orientation: Push-in micro SD socket
Compatibility
• Arduino Uno / Nano / Mega
• ESP8266 / ESP32
• STM32, AVR, PIC microcontrollers
• Raspberry Pi (SPI mode)
Key Advantages
• Easy expansion of storage capacity
• Supports large data logging applications
• Simple SPI-based interfacing
• Widely supported by Arduino and embedded libraries
Technical Insights
• SD cards operate internally at 3.3 V
• SPI mode is slower than native SD mode but simpler
• Use proper chip select handling for multiple SPI devices
• Requires stable power during write operations
Applications
• Data loggers
• Sensor data storage
• Audio and media playback
• Configuration and firmware storage
• IoT data recording systems
Pro Tip
• Always format SD cards to FAT32 for best compatibility
• Avoid removing the card during read/write operations
• Use short SPI wires to prevent data corruption
Package Includes
• 1 × Micro SD Card Reader Module
