NXP i.MX RT MCU Technology Powers Our Smartwatch Future

The evolution of wearable devices is fueled by rapid advances in technology including enhanced processor performance, extended battery life, continuous connectivity, smarter sensing, monitoring and tracking and user-friendly interfaces — all within ever-shrinking form factors and power budgets.

Evolution of Smartwatch Designs

Smartwatches have become essential wearables for our smart, connected and active lifestyles. The smartwatch concept arose decades ago with sci-fi gadgets like Dick Tracy’s two-way wrist radio/TV, the Jetson’s clunky video wristwatches and “wrist communicators” debuting in Star Trek movies. Digital watches with LED screens—the precursor to smartwatches—came to market in the early 1970s, and the first true smartwatches with processing and telecom capabilities appeared in the late 1990s.

Smartwatches continued to evolve in the 2000s, competing with wrist-worn fitness trackers. Today’s designs are feature-rich, wirelessly connected “wrist computers", offering the biometric health monitoring capabilities of fitness trackers, along with touchscreen and voice control, graphics, multimedia and mobile telephony – all the functionality of a smartphone in a wrist-sized form factor.

Trending Now: Feature-Laden Smartwatches for Health-Conscious Lifestyles

Growing consumer demand for feature-rich smartwatches is one factor driving this market growth, especially among tech-savvy millennial and urban populations. Smartwatches are attracting new users, including older adults, as wearable makers add health-monitoring features, enabling users to track their health status and biometrics in real time.

Today’s smartwatches are more capable than models from even a few years ago. Smartwatches typically communicate with the cloud and streaming services through Bluetooth-connected smartphones or directly through Wi-Fi, 4G-LTE or 5G. Battery life has improved in recent years, extending from days to multiple weeks between charges for some smartwatch models. Organic LED (OLED) and active-matrix organic LED (AMOLED) displays, vivid graphical user interfaces with animation, voice control and audio playback provide more intuitive user experiences. Today’s smartwatches also have more robust, built-in security features to protect personal and commercial data.

Smartwatch biometric sensing capabilities have become more sophisticated, extending beyond the features of basic fitness/activity trackers to support an array of health monitoring functions including SOS emergency services, safe zone alerts, contact tracing and vitals monitoring and reporting. Some smartwatches also offer “wearables as a service” capabilities including personal health and well-being monitoring (for instance, sleep patterns, heart rate monitoring, fall detection and oxygen levels), location monitoring for kids, older adults and pets and remote healthcare for cardiac care, diabetes management and physical therapy.

Many feature-packed smartwatch designs offer sport modes with virtual trainers, music storage and playback, voice calling capability, local voice control and cloud-based voice assistants like Amazon Alexa and Google Assistant. For example, Amazfit GT3  watches offer advanced features such as up to 21-day battery life, an Ultra HD AMOLED display, 24-hour health management, more than 150 sport modes and Amazon Alexa for voice control. Another standout is Garmin’s Venu 2 Plus,  a fitness smartwatch built for active lifestyles supporting voice calling, animated watch workouts, sleep scores and general health monitoring. Wearables are also evolving beyond the wrist to include eyewear such as Ray-Ban’s Stories  smart glasses with photo capture, video recording and audio playback features in a stylish form factor.

Designing Battery-Friendly, Secure Smartwatches with NXP’s i.MX RT MCU Families

To compete in today’s dynamic smartwatch market, it helps to work with a leading platform provider. By using a market-proven processing platform, you can focus on what you do best: designing innovative, differentiated smartwatch products. As your wearables technology partner, NXP offers a broad low-power microcontroller (MCU) portfolio, advanced voice software, robust security technology and a comprehensive development ecosystem.

Successful smartwatch designs begin with an optimized system-on-chip (SoC) platform. NXP’s i.MX RT500 and i.MX RT600 families of secure crossover MCUs offer an ideal balance of low-power processing and high-performance capabilities, along with rich integration and advanced security. The i.MX RT500/600 MCUs pair the real-time functionality of an Arm^® Cortex^®-M33 core with a high-performance DSP core to help unlock the potential of smart, connected wearable applications.

Extend Battery Life with NXP’s Low-Power Technology

The i.MX RT 500/600 MCUs provide an optimal balance of high performance and power efficiency. The MCUs can run parallel tasks leveraging the Arm^® Cortex^®-M33 core running at up to 300 MHz, integrated Cadence^® Tensilica^® Fusion F1 or HiFi 4 DSP cores, a PowerQuad math engine, a 2D GPU for graphics processing and a host of on-chip peripheral interfaces. This clever multitasking approach enables wearable designs to use the right processing tool or interface for the task.

The MCUs offer multiple power modes for energy-efficient heterogeneous computing. For example, the Cortex-M33 processor can remain in sleep mode while the DSP is hard at work. The i.MX RT MCU power architecture supports dynamic voltage and frequency scaling (DVFS) and multiple clock dividers, enabling easy throttling of processing cores. By adjusting core speeds up or down as needed, wearable designs can use integrated, low-power clock sources instead of higher power external sources. These low-power MCU innovations enable an extended battery life of up to three weeks in smartwatch mode.

Add Voice to Your Smartwatch Designs for Hands-Free Control

NXP’s i.MX RT MCUs with integrated Tensilica Fusion 1 or HiFi 4 DSPs provide the right level of high-performance audio DSP capabilities to enable smartwatch voice assistance and voice calling features. Our voice intelligent technology (VIT) is a free, comprehensive voice control software package delivered as a ready-to-use library in the MCUXpresso SDK. VIT enables customer-defined wake word and voice commands using NXP’s online model creation tool.  In addition to VIT, NXP offers premium voice enablement and speech processing technologies including:

• VoiceSeeker – advanced audio front-end signal processing for voice control, incorporating beamforming, advanced noise reduction and acoustic echo cancellation
• VoiceSpot – low-power wake word engine, enabling reliable voice triggering
• Conversa – multi-microphone, full-duplex telephony suite for voice calls

Give Your Smartwatch Design Vivid Graphics and Flexible Display Interfaces

The i.MX RT500 MCUs modernize HMI design for power-sensitive applications by enabling vivid graphics with an integrated 2D GPU. Further simplifying graphics development, NXP’s comprehensive software ecosystem includes an extensive list of third-party solutions from partners.

Zepp OS UI,  powered by AMETEK Crank software,  enables compelling, smartphone-like experiences in small form factors like the Amazfit GT3 smartwatches. Based on FreeRTOS open-source code, Zepp OS is one of the lightest smartwatch operating systems available, helping smartwatches operate up to three weeks on a single charge on low-power, high-performance MCUs like the i.MX RT500 family.

The AMETEK Crank Storyboard GUI framework is directly accessible within NXP’s MCUXpresso IDE toolkit, which greatly streamlines the process of evaluating NXP MCUs and creating rich embedded GUIs.

Secure 24-Hour Health Management

Today’s always-connected smartwatches continuously monitor health and fitness biometrics such as heart rate and activity during the day. Sleep monitoring also has become a popular use case for many smartwatch designs. To make it easy to collect biometric data without CPU intervention, i.MX RT MCUs include a low-power DMA engine and an array of low-power sensor interfaces such as the I²C and I³C buses.

Today’s smartwatches are capable of sharing biometric data with remote health care providers for monitoring and diagnostics. These wireless connections must be secure and private to protect user data. Securing smartwatch designs requires a powerful yet easy-to-implement security framework based on strong isolation and proven hardware security technologies. To help protect smartwatches and other wearables against intrusion, NXP’s i.MX RT MCUs offer advanced, built-in security features including secure boot, unique key storage and hardware acceleration of symmetric and cryptographic algorithms.

Connect with NXP and Drive the Next Generation of Smartwatches

As new smartwatch use cases emerge, NXP’s advances in crossover MCUs, wireless connectivity, sensor interfaces, voice software and security technology will continue to meet the evolving needs of wearable designs. NXP’s comprehensive software solutions and third-party ecosystems help developers optimize their smartwatch designs, reduce cost and complexity within miniature form factors and accelerate time to market. Explore NXP’s solutions for smartwatches and other wearables or download our brochure.