The RC522 RFID Reader module is designed to operate at a frequency of 13.56 MHz. It's based on the MFRC522 IC from NXP and is one of the most inexpensive RFID modules. It comes with a RFID card and a key tag with 1 kB of memory, which can be written by the module to store some sort of secret message in it.

The reader can communicate with a microcontroller over a 4-pin Serial Peripheral Interface (SPI) with a maximum data rate of 10Mbps. It also supports communication over I2C and UART protocols. This module comes with an interrupt pin, which is handy because instead of constantly asking the RFID module, the module will alert when a tag comes into its vicinity.

Specifications

• Operation voltage: 2.5 V - 3.3 V
• Maximum operation current: 13 mA - 26 mA
• Frequency range: 13.56 MHz ISM Band
• Communication interface: SPI/I2C/UART
• Input logic level: 5 V tolerant
• Maximum effective distance: approx 5 cm
• Standard tags: ISO 14443A

Dimensions

Tutorial

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