1 General description
CLRC661, the high performance multiprotocol NFC frontend.
The CLRC661 multiprotocol NFC frontend IC supports the following operating modes
• Read/write mode supporting ISO/IEC 14443 type A and MIFARE Classic communication mode
• Read/write mode supporting ISO/IEC 15693
• Read/write mode supporting ICODE EPC UID/ EPC OTP
• Read/write mode supporting ISO/IEC 18000-3 mode 3/ EPC Class-1 HF
The CLRC661’s internal transmitter is able to drive a reader/writer antenna designed to communicate with ISO/
IEC 14443A and MIFARE Classic IC-based cards and transponders without additional active circuitry. The
digital module manages the complete ISO/IEC 14443A framing and error detection functionality (parity and
CRC).
The CLRC661 supports the communication of MIFARE Classic with 1K memory, MIFARE Classic with 4K
memory, MIFARE Ultralight, MIFARE Ultralight C, MIFARE Plus, and MIFARE DESFire products. The CLRC661
supports higher transfer speeds of the MIFARE family up to 848 kbit/s in both directions.
The CLRC661 supports the vicinity protocol according to ISO/IEC15693, EPC UID and ISO/IEC 18000-3 mode
3/ EPC Class-1 HF.
The following host interfaces are supported:
• Serial Peripheral Interface (SPI)
• Serial UART (similar to RS232 with voltage levels dependent on pin voltage supply)
• I2C-bus interface (two versions are implemented: I2C and I2CL)
The CLRC661 supports the connection of a secure access module (SAM). A dedicated separate I2C interface is implemented for a connection of the SAM. The SAM can be used for high secure key storage and acts as a very performant cryptocoprocessor. A dedicated SAM is available for connection to the CLRC661. In this document, the term „MIFARE Classic card“ refers to a MIFARE Classic IC-based contactless card.

2 Features and benefits
• Includes NXP ISO/IEC14443-A intellectual property licensing rights
• High performance multiprotocol NFC frontend for transfer speed up to 848 kbit/s
• Supports ISO/IEC 14443 A
• MIFARE Classic encryption supported by hardware
• Allows reading cards based on MIFARE Ultralight, MIFARE Classic with 1K memory, MIFARE Classic with 4K
memory, MIFARE DESFire EV1, MIFARE DESFire EV2 and MIFARE Plus ICs
• Supports ISO/IEC15693, ICODE EPC UID, and ISO/IEC 18000-3 mode 3/ EPC Class-1 HF
• Low-Power Card Detection
• Supported host interfaces:
– SPI up to 10 Mbit/s
– I2C-bus interfaces up to 400 kBd in Fast mode, up to 1000 kBd in Fast mode plus
– RS232 Serial UART up to 1228.8 kBd, with voltage levels dependent on pin voltage supply
• Separate I2C-bus interface for connection of a secure access module (SAM)
• FIFO buffer with size of 512 bytes for highest transaction performance
• Flexible and efficient power-saving modes including hard power down, standby, and low-power card detection
• Cost saving by integrated PLL to derive system clock from 27.12 MHz RF quartz crystal
• 2.5 V to 5.5 V power supply
• Up to 8 free programmable input/output pins
• Typical operating distance in read/write mode for communication to a ISO/IEC 14443 type A and MIFARE
Classic card up to 12 cm, depending on the antenna size and tuning

3 Applications
• ISO/IEC 14443 reader
• ISO/IEC 15693 reader
• Reader for MIFARE product-based cards
• Reader for NTAG and NTAG 5 based products
• Gaming