Automobiles are the most widely used means of transportation, and most of them are switches that mechanically and manually control car door handles. Since the birth of the car, the car key has gone through multiple stages of development: from the physical key to the remote control key for remote control to switch the door, to the smart key for keyless start, the mobile phone cloud key, and the mobile phone bluetooth key. The unlocking methods derived from it also have their own merits-cards, passwords, fingerprints, and mobile phones. All in all, “car key” has evolved from a physical object to a concept. The focus of this article is NFC. If NFC technology is applied to electric car door handles, it can be operated and controlled by near-field communication devices (such as mobile phones), which is smarter, more practical and convenient than mechanical and manual control of car door handles. NFC in combination with the automotive market is a good application prospect. NFC can communicate through encrypted protocols and close contact, which can be very safe to ensure that the door is opened and closed correctly.
For the application of NFC car keys, the earliest model was the Tesla Model 3. After that, Nio, a new domestic car-making force, also implemented the NFC unlocking function, but they were all cards similar to bus cards as the carrier. Later, BYD took the lead in launching the mobile phone NFC car key function in the domestic market, first adapting to the car.Type: BYD Qin Pro Beyond Edition, Song Pro, with mobile phones as the carrier, you only need to place the mobile phone close to the part where the signal receiver is located to unlock the vehicle when using it, just like using a mobile phone to swipe the gate into a subway station.
In view of the application of NFC car keys, Dalian Taiping Group has launched a car door handle solution based on the NXP automotive MCU chip S32K118/116 and the automotive NFC controller chip NCF3320. The main form of the scheme is a long strip shape, which is mainly used on car door handles or rearview mirrors. The main function is to unlock the car door through a digital key, which replaces the traditional key and is safer and more convenient. The chip data, software code, NFC library, and hardware data involved in this program need to sign an NDA agreement before they can be obtained.
►Scene application diagram
►Display board photo
►Plan block diagram
►Core technical advantages
Key device advantages of NXP S32K118： 1. Automotive-grade high performance: Cortex™-M0+ core, 48MHz frequency 2. Rich peripheral resources： · 256KB Flash，2KB EEPROM · 12-bit 1 Msps ADC, 16-bit FlexTimers · Up to 58 I/Os are available for use · Support CAN FD, FlexIO (UART, I2C, SPI, I2S, LIN, PWM) * Scalable low-power operation and stop modes. Fast wake-up, clock, and power gating 3. Strong compatibility: 48-pin LQFP package, all series of 48-pin P2P compatible 4. Easy to use: MCU-based developers are easy to use and improve performance while leveraging the tool chain. Key device advantages of NXP NCF3320： 1. NFC full protocol support： · Support ISO/IEC 14443 A/MIFARE, ISO/IEC 14443 B and FeliCa · P2P passive starter mode in accordance with ISO/IEC 18092 · Support ISO/IEC15693, ICODE EPC UID and ISO/IEC 18000-3 mode 3/EPC Class-1 HF 2. Flexible and efficient power-saving modes: hard power-off, standby, and low-power card inspection, with the lowest average power consumption of 15uA 3. Rich host interface： * SPI: up to 10 Mbit/s ·I2C: The bus interface is up to 400 kBd in fast mode and up to 1000 kBd in fast mode+ *RS-232: serial UART up to 1228.8kBd, voltage level depends on the power supply pin
►Program specifications
1. Processor: ARM® Cortex-M0+ 2. Memory: on-chip 256K Flash, 2K EEPROM 3. Frequency: main frequency 48MHz 4. Wireless transmission technical specifications: 13.56MHz 5. Antenna size: 72 x 18 mm 6. Card inspection distance: Mifare Card-6 cm, T5T Card-5 cm, 2 cm in LPCD mode 7. Working temperature: -40℃ to +125℃ 8. Supported operating system: FreeRTOS 9. Development platform: NXP S32 Design Studio 10. Power consumption: S32K118 consumes 27uA in VLPS mode； NCF3320 in LPCD mode, the average power consumption is 15~17uA；
