New Automotive Wireless Charging Solution with NFC Communication

Combining ROHM’s automotive-grade wireless power transmission control IC with STMicroelectronics’ NFC reader IC and 8-bit microcontrollerenables innovative products in automotive applications

ROHM has recently announced the development of an automotive wireless charging solution with integrated NFC communication. This solution combines ROHM’s automotive-grade (AEC-Q100 qualified) wireless power transmission control IC (BD57121MUF-M) with STMicroelectronics’ NFC Reader IC (ST25R3914) and 8-bit microcontroller (STM8A series). In addition to being compliant to WPC’s Qi standard supporting EPP (Extend Power Profile) that enables the charger to supply up to 15W of power, the multi-coil design enables a wide charging area that provides some spatial freedom in vehicle applications (2.7x greater charging range vs single coil configurations). This means that consumers do not need to worry much about exactly aligning their smartphones to the provided charging area in order to be able to charge wirelessly.

Key Features

  1. Foreign object detection (detects NFC cards in smart cases)

automotive wireless charging with NFC

Per the Qi standard, a foreign object detection function for detecting metallic objects is included to prevent deformation or damage from occurring due to excessive heat generation in the event a metallic object is placed between the transmitter and receiver. This time, however, designers were faced with the challenge of ensuringdetection of the NFC antenna without damaging the NFC card by the magnetic field.This was achieved by integratinga NFC communication function that enables detection of theNFC card even when inserted in a smartphone case or sleeve.

  1. NFC enables seamless infotainment operation via device authentication

automotive wireless charging with NFC

Previously, when connecting smartphones to infotainment systems it was necessary to perform manual pairing for each device. However, by combiningQi wireless charging with NFC communication ROHM made it possible to not only charge mobile devices such as smartphones but also perform Bluetooth or WiFi pairing at the same time through NFC authentication.To use, simply place a smartphone on the charging pad to automatically initiate screen sharing with the infotainment and navigation system. 

  1. Achieves system sharing via personal authentication using NFC 

In the future, all vehicles are expected to utilize NFC protocol to connect smart devices with the onboard system to provide shared functionality that does not rely on traditional keys or dedicated cards.

A reference board integrating this solution will be exhibited at the 11th International Car Electronics Technology Show at Tokyo Big Sight from January 16-19, 2019.In the future ROHM plans on releasing a sample reference board thatwill allow users to easily configure a wireless charger for automotive use compatible with the latest Qi standard (EPP), when combined with our Qi certified receiver board (BD57015GWL-EVK-002) already on the market,.

ROHM is committed to develop solutions that will enable greater convenience and performance for the rapidly expanding wireless charging market.