Automotive NFC reader specially created for CCC digital key applications

STMicroelectronics ST25R3920 Automotive NFC Reader, available now from Mouser, is an AEC-Q100 qualified Near Field Communication IC, specially created for CCC digital key applications. The device supports NFC Initiator, Target, Reader, and Card emulation modes, and adheres to CCC Digital Key Release 2.0. This device meets the demands for car access/start applications in areas like a door handle or centre console. It enables additional functionality, like pairing or NFC card protection combined with a Qi wireless charger.

As the device features Dynamic Power Output and Noise-Suppression Receiver technologies, it increases RF output power. It provides an enhanced input-circuit design for rapid car-key response and superior user convenience.

With DPO, the device functions at up to 1.6W continuous RF output power and 2.5W short-term input peak, to maintain reliable NFC connections across the distance with a small antenna. NSR technology improves immunity to interference from noise sources and consequently simplifies electromagnetic immunity and eases certification. Also, automatic antenna tuning compensates for variations in the RF environment to maintain the best possible connection to the user’s smartphone, and low-power key-signal detection with inductive wakeup reduces the load on the battery when the key is not being used.

The device features high RF power with dynamic power output to directly drive antennas at high efficiency, delivering large interaction distance even with small antenna sizes common in door handles. The device incorporates extra features, making it incomparable for low power applications. It allows low power card detection by doing a measurement of the amplitude or phase of the antenna signal while decreasing power consumption to a minimum. Furthermore, it includes a low power capacitive sensor to identify the presence of a card without switching on the reader field.

The Automotive NFC Reader is provided in a compact 5mm x 5mm VFQFPN32 package, perfect for space-constrained applications.