STMicroelectronics (ST), a global semiconductor company that supplies semiconductors for a wide range of electronic applications to ARM, announced that the two companies' joint NFC solution has been incorporated into ARM's new wearable reference design, providing secure, high-performance NFC and microcontroller capabilities.

This NFC solution, jointly developed by ST and ams, consists of ST's ST54E, which provides an NFC controller and a Secure Element based on the global platform standard version 2.2 in a System-in-Package (SiP) format, and ams's AS39230 NFC analog front-end featuring BoostedNFC technology. This joint NFC solution is particularly suitable for ultra-small battery-powered products such as wearable devices and smartphones.

ams's BoostNFC technology has overcome the problems that existing NFC devices face when operating with small antennas in demanding RF transmission environments. The ams/ST solution exceeds EMVCo requirements suitable for the RF performance needed for contactless payment methods, even when operating with antennas much smaller than 100mm².

Because ST’s SiP comprehensively supports all major NFC security standards worldwide, the ARM mbed wearable reference design can support the types of secure transactions required in various IoT (Internet of Things) applications, including contactless payment, automatic toll collection, and access control, as well as those not covered here.

The joint solution from ams/ST has very low average power consumption, which enables extended battery operating time per charge, i.e., charging intervals. This characteristic is possible because power cycling can be perfectly configured for both the BoostNFC front end and the NFCC.

The NFC system utilizes the unique technology of the ams AS39230, which implements active load modulation. This feature boosts the transmission signal of the NFC frontend to enable the wearable reference design to surpass the performance of contactless cards with antennas that are typically about 40 times larger in the 'Operating Volume'—the area where the wearable reference design interacts with the NFC reader.

The tight compatibility between each discrete component of ST and ams provides complex power saving performance. The ST54E switches to Deep Power-Down mode when out of the NFC RF field, while the AS39230 quickly switches to active power mode, which consumes much less power, with an average current consumption of only 18µA. The software for the ams/ST solution is optimized for low-power microcontrollers based on ARM technology. Because it offers a modular design, users can choose to compile only the modules suitable for the use cases supported by the device, which is useful for reducing system memory requirements and optimizing the resource footprint. The software stack optionally supports peer-to-peer (P2P) and reader/writer functions, and enables over-the-air (OTA) updates while the device is in the field.

The ST54E has received full approval, allowing developers to use NFC devices in card emulation, P2P, and tag reader modes compliant with NFC Forum standards. Furthermore, it is suitable for use in applications requiring global approval, including those under the Common Criteria (CC), EMVCo, GlobalPlatform, Visa, Mastercard, Amex, Discover, and the People's Bank of China (PBoC). The security performance of this mbed wearable reference design is enhanced by a separate fingerprint reader. The fingerprint reader utilizes ST's STM32F411 Dynamic Efficient microcontroller based on an ARM Cortex®-M4 core and performs image processing and identification functions.