RC522 RFID Reader Writer SPI Module with Card & Tag

RC522 RFID Reader Writer SPI Module with Card & Tag The RC522 RFID module is based on the NXP MFRC522 IC — a highly integrated, low-power 13.56 MHz contactless communication chip. It supports ISO/IEC 14443A / MIFARE and communicates via SPI at up to 10 Mbit/s. This module is widely used in access control, attendance systems, smart lockers, and IoT security projects. Specifications Model MFRC522 (NXP) Operating Frequency 13.56 MHz Supply Voltage 3.3V DC only (do NOT use 5V) Operating Current 13 – 26 mA Idle Current 10 – 13 mA Interface SPI (up to 10 Mbit/s) FIFO Buffer 64 bytes Read/Write Distance Up to 50 mm (typical 20–50 mm) Protocol ISO/IEC 14443A, MIFARE Max Transfer Speed 848 kBd Board Dimensions 60 × 39.5 mm Weight 20 g Features Highly integrated analog circuitry for demodulation and response decoding ISO/IEC 14443A / MIFARE standard — compatible with most commercial RFID cards and tags SPI interface up to 10 Mbit/s — fast, reliable for real-time applications 64-byte FIFO buffer for efficient send and receive operations Flexible interrupt modes for low-overhead MCU integration Software power-down mode for battery-powered deployments Programmable timer, CRC coprocessor, and internal self-test 2.5V to 3.3V supply range How It Works The RC522 generates a 13.56 MHz electromagnetic field via its onboard antenna. When a compatible RFID card or tag enters the field (within ~50 mm), it powers up inductively and exchanges data with the module. The MFRC522 decodes the response and passes the card UID and payload to the host microcontroller over SPI. Common Applications Door access control and smart lock systems Student and employee attendance systems Library book and asset tracking Smart locker and vending machine authentication Contactless payment prototypes IoT identity verification and security projects SPI Wiring Reference RC522 Pin Arduino Uno ESP32 SDA (SS) D10 GPIO 5 SCK D13 GPIO 18 MOSI D11 GPIO 23 MISO D12 GPIO 19 RST D9 GPIO 27 GND GND GND 3.3V 3.3V 3.3V ⚠ Warning: Always connect VCC to 3.3V only. Connecting to 5V will permanently damage the module. Package Contents 1 × RFID RC522 Reader/Writer Module 1 × Blank ISO RFID Card (1K S50) 1 × Keychain RFID Tag 1 × Straight pin header strip 1 × Right-angle pin header strip