NFC Extend Click Board™

Product Code: MIKROE-3971

How Does The NFC Extend Click Board™ Work? The active NFC tag component on the NFC Extend Click Board™ is the ST25DV16K - the compact NFC tag IC from STMicroelectronics. The Click board™ itself has a reasonably small number of components because most of the interface and EEPROM memory circuitry is already integrated on the ST25DV16K IC. The I2C / SMBus compatible serial interface lines, along with the GPO pin, which also works in the open drain configuration, are pulled up by the on-board resistors. The 2-Wire lines are routed to the respective I2C lines of the mikroBUS™ (SCK and SDA), while the GPO pin of the main IC is routed to the INT pin of the mikroBUS™. Depending on the application requirements various shapes and sizes of 13.56 MHz external antenna can be used by connecting them to CN1 (male U.FL) connector. The NFC Extend Click Board™ can utilize new antennae that we have recently released. The ST25DV16K uses the I2C/SMBus compatible communication interface, offering a fast transfer mode (FTM), to achieve a fast link between RF and contact worlds, via a 256 byte buffer called Mailbox.

This mailbox dynamic buffer of 256 byte can be filled or emptied via either RF or I2C. There is also the INT pin available, which indicates incoming event to the contact side, like RF Field changes, RF activity in progress, RF writing completion or Mailbox message availability. The built in energy harvesting element can deliver µW of power when external conditions make it possible. The integrated RF management allows the NFC Extend Click to ignore RF requests. All these features can be programmed by setting static and/or dynamic registers of the ST25DV16K. ST25DV16K can be partially customized using configuration registers located in the E2 system area. More information about all the registers can be found in the ST25DV16K datasheet. However, provided library contains functions that simplify the use of the NFC Extend Click. The included application example demonstrates their functionality and it can be used as a reference for custom design. The NFC Extend Click Board™ can be supplied and interfaced with both 3.3V and 5V without the need for any external components. The onboard SMD jumper labelled as VCC SEL allows voltage selection for interfacing with both 3.3V and 5V MCUs. SPECIFICATIONS Type RFID/NFC Applications NFC enabled business cards, stickers, wristbands, key fobs, pens, movie passes, hang tags, medication bottles, and many more. On-board modules ST25DV16K - the compact NFC tag IC from STMicroelectronics Key Features Fast data transfer between I2C and RF interfaces, half-duplex 256-byte dedicated buffer, energy harvesting, data protection features, custom size and shape external antenna. Interface I2C Compatibility mikroBUS Click board size S (28.6 x 25.4 mm) Input Voltage 3.3V or 5V PINOUT DIAGRAM This table shows how the pinout of the NFC Extend Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns). Notes Pin Pin Notes NC 1 AN PWM 16 NC NC 2 RST INT 15 INT Interrupt output NC 3 CS RX 14 NC NC 4 SCK TX 13 NC NC 5 MISO SCL 12 SCL I2C Clock NC 6 MOSI SDA 11 SDA I2C Data Power Supply 3.3V 7 3.3V 5V 10 5V Power supply Ground GND 8 GND GND 9 GND Ground ONBOARD SETTINGS AND INDICATORS Label Name Default Description PWR LED GREEN - Power LED Indicator JP1 VCC/SEL Left Power supply voltage selection: left position 3V3, right position 5V