The MLX90132 from Melexis has been designed to handle sub-carrier frequencies from 106 to 848 kHz and baud rates up to 848kbit/s.
The MLX90132 is a 13.56MHz RFID/NFC reader IC. It has been designed to handle sub-carrier frequencies from 106 to 848 kHz and baud rates up to 848kbit/s.
MLX90132 has both tag and field detection capabilities. The tag detection capability is based on the detection of a variation in the device HF field. If a metallic object approaches or moves away from the antenna, it influences the amplitude of the HF field. The device is able to detect any HF field variation for a very short period of field presence. If the new field value is outside a prerecorded field range, the device wakes up the microcontroller and initiates communication with the tag.
Developed for short to mid-range (less than 7 feet) applications, the transmitter provides up to 300 milliwatts of RF power to a matched antenna load.
The device is implemented as an analog section and a digital section. The digital portion supports the low protocol layers from API down through to the PHY. A digital demodulator based on sub-carrier detection and programmable bit / symbol ENDEC (encoder / decoder) drives the physical layer. The demodulator also handles the start / stop bits, parity bits, and additional framing overhead.
To support a variety of microcontrollers, especially lower cost devices, the MLX90132 has a 256 byte internal buffer which is sufficient to hold an entire data frame. Microcontroller interface is provided through a standard SPI / UART port.
Analog circuitry includes built in reference oscillator and internal clock for programmable wake-up intervals. Critical for battery operation in automotive applications, the MLX90132 has 6 power modes for optimal power consumption. In ready state current consumption is 2.5 mA and is reduced to 10 uA in its lowest power mode, Hibernate.
The robust and flexible receiver part of the MLX90132 enables designers of NFC reader devices to fit their system requirements and to address the main communication standards with the same device. Form factor is minimized with a 32-pin 5×5 QFN package. Targeted for automotive and industrial markets, this is temperature rated -40C to +105C, and conforms with ISO/IEC 18092, 14443 (A and B), 15693 and 18000-3 (mode-1).
The MLX90132 is readily available and can be purchased in through Digi-Key for less than $3.50, depending on volumes. For complete details, application notes and specifications, please refer to the MLX90132 Home Page .