As technology advances, electronic products are becoming smaller and more intelligent, with network connectivity becoming a fundamental feature. Products such as miniature Bluetooth healthcare devices, wearable technology, smart entertainment devices, and augmented reality (AR) and virtual reality (VR) solutions are gradually transforming the way we live. This article introduces the design concepts for these electronic products and the product features of related solutions offered by Silicon Labs.
Designing smarter, more compact Bluetooth healthcare and wearable devices
To build a compact and rigorously demanded Bluetooth healthcare device, it is not just about selecting the smallest hardware components from the market. You can also reduce the product size by optimizing the Bill of Materials (BOM), using integrated Bluetooth SoCs and modules, and incorporating various peripheral functions and features required in healthcare applications. This can save a significant amount of PCB footprint, enhance design flexibility, and reduce costs.
To design Bluetooth healthcare devices, several design concepts can be used to accelerate product development and integrate more functions. Firstly, Bluetooth healthcare devices can utilize integrated AI/ML accelerators to enhance the device's intelligent control functions. Through machine learning (ML), it is possible to process large amounts of sensor data based on existing models to identify irregularities and determine which data needs to be transmitted back to the cloud. Nowadays, wireless devices can transmit all collected data back to the cloud for processing and analysis. By identifying key data on the device, transmitting only certain subsets of data back can save valuable resources and extend battery life.
Artificial Intelligence (AI) can also be used for applications such as elderly care at home. In these applications, monitoring vital signs, tracking data changes, observing gait patterns, and generally identifying abnormal patterns can provide crucial diagnostic data to providers. It can also trigger life-saving alerts to caretakers and family members, greatly improving, and even saving, the lives of patients.
In addition, these products require integration of more analog peripherals, such as ADCs that can be used in many wireless healthcare and wearable devices for sensor measurements and battery power monitoring. For manufacturers of continuous glucose monitoring (CGM) and other portable healthcare devices using discrete analog front-end (AFE) solutions, ADCs and DACs are two key functions that can be used on the chip.
Low power consumption for enhanced energy efficiency and battery life
DC-DC converters are a crucial component for battery-powered healthcare devices. Boost converters allow SoCs to use low-voltage batteries, such as alkaline and silver oxide batteries, with an input range of 0.8 to 1.7 V. This enables Bluetooth SoCs to operate at lower power voltages. Buck converters allow SoCs to use other 3V batteries, such as lithium coin cells, to improve energy efficiency and battery life or reduce battery size.
To predict and prevent unexpected battery depletion during critical health applications, coulomb counters, which are charge measurement devices, can accurately track battery charge to enhance user safety and experience. Additionally, low-frequency RC oscillators are key components for Bluetooth Low Energy (LE) 2.4 GHz applications, where Bluetooth LE SoCs need to meet a specified sleep clock accuracy of ±500 ppm.
Given the low power levels used by healthcare and wearable devices, it's important to reduce the number of PCB layers and components in the design while maintaining acceptable RF performance when matching networks. Minimizing Bluetooth device power consumption is essential, allowing device manufacturers to reduce the form factor of the devices.
Promising prospects for the global AR/VR device market
Today's consumers are increasingly home-centric—work, education, healthcare, shopping, and entertainment need to be accessible from home. With AR/VR technology, the boundaries between the real world and the digital world are intertwined. You can put on an AR/VR head mounted display (HMD), grab a pair of handheld controllers, and truly immerse yourself in 3D games or movies. Alternatively, you can enter a realistic virtual shopping mall from home, try on new clothes, or see how a new sofa looks. AR/VR applications can enhance consumer experiences, making our lives more efficient. By 2027, the global AR/VR device market is expected to see a compound annual growth rate (CAGR) of 26% for AR/VR applications.
Wearable AR/VR devices present unique wireless design challenges. They must be extremely energy-efficient to maximize battery life and charging intervals while minimizing battery weight. At the same time, they need to handle high-bandwidth video to provide a natural visual experience. The latency between VR controllers and HMD is critical, requiring minimal delay for timely responses to gestures and motion.
AR and VR applications have three key wireless requirements: low power consumption, low latency, and stable connection. Energy efficiency is crucial for improving the user experience of battery-powered and rechargeable devices such as VR controllers, smart glasses, and AR/VR headsets. In addition, security is one of the top concerns for users of connected devices, as HMD and VR controllers can serve as gateways for malicious attacks on home networks.
Highly integrated Bluetooth low energy SoCs
Silicon Labs offers a variety of SoCs and modules for Bluetooth wireless connectivity and control applications. Below are some key products and their features.
The EFR32BG22 series is a cutting-edge Bluetooth Low Energy (BLE) SoC known for its energy efficiency and receiver (RX) sensitivity, making it ideal for energy-saving smart entertainment devices. The SoC measures just 4 x 4 mm and supports Secure Vault features. Part of the Wireless Gecko Series 2 platform, both the EFR32BG22 and EFR32BG22E BLE SoC solutions are designed with a strong focus on energy efficiency, offering ultra-low transmit and receive power. The high-performance, low-power Arm® Cortex®-M33 core provides industry-leading energy efficiency, potentially extending the lifespan of button cell batteries up to ten years.
Silicon Labs’ BG22 assists in creating energy-efficient applications, while the BG22E ("E" stands for Energy Conservation) further enhances energy efficiency by extending battery life and supporting completely battery-free designs. The BG22 and BG22E series are ideal SoCs for Ambient IoT or energy harvesting devices. Target applications include low-power nodes in Bluetooth mesh networks, smart locks, personal healthcare, and fitness devices.
The EFR32BG27 series features compact, ultra-low-power SoCs available in WLCSP (2.3 x 2.6 mm) and QFN packages, supporting high-performance Bluetooth Low Energy. These SoCs include a DCDC boost converter for a wide voltage range and a coulomb counter for accurate battery level tracking, and they support PSA Level 2 security. The EFR32BG27 series wireless SoCs can operate on button cell batteries, opening up new possibilities for device manufacturers. This series allows manufacturers to meet the demands of extremely small form-factor applications without sacrificing performance and security.
The BG27 Bluetooth SoC integrates DCDC boost functionality, enabling operation at voltages as low as 0.8 volts, supporting single-cell alkaline and 1.5-volt button cell batteries. Additionally, the BG27's wake-up pin allows products to remain off for months during warehouse storage or transportation, consuming less than 20 nA of power, ensuring the battery remains usable. The integrated coulomb counter accurately monitors battery levels, preventing unexpected battery depletion in critical applications. Target applications include connected healthcare devices, wearables, sensors, switches, smart locks, and commercial and LED lighting.
The EFR32BG24 is a high-performance wireless and low-power SoC suitable for battery-efficient smart wearable devices, featuring an integrated AI/ML accelerator and Secure Vault™ with the highest PSA Level 3 certification. The EFR32BG24 wireless SoC is ideal for IoT wireless connectivity using Bluetooth Low Energy and Bluetooth Mesh networks, suitable for smart home, lighting, and portable healthcare products.
With its high-performance 2.4 GHz RF, low current consumption, AI/ML hardware accelerator, and Secure Vault™, IoT device manufacturers can create smart, robust, and energy-efficient products, protecting against remote and local cyber-attacks. The ARM Cortex®-M33 runs up to 78 MHz, with 1.5 MB of flash memory and 256 kB of RAM, providing resources for demanding applications while allowing room for future growth. Target applications include gateways/hubs, sensors, switches, door locks, smart plugs, LED lighting, luminaires, blood glucose meters, and pulse oximeters.
Solutions for ultra-low-power IoT wireless devices
The EFR32FG22 (FG22) Series 2 Proprietary Wireless 2.4 GHz SoC offers industry-leading energy efficiency and receiver (RX) sensitivity, making it ideal for energy-saving smart entertainment devices. It features a tiny footprint of only 4 x 4 mm and supports Secure Vault features. The EFR32FG22 and EFR32FG22E proprietary wireless 2.4 GHz SoC solutions are part of the Wireless Gecko Series 2 platform.
The FG22 SoC integrates a 38.4 MHz Arm® Cortex®-M33 core with TrustZone and a high-performance radio with a receive sensitivity of -102.3 dBm. The FG22 allows you to create energy-saving applications, while the FG22E (“E” for Energy Conservation) further enhances energy-saving advantages by extending battery life and supporting fully battery-free designs. This SoC combines ultra-low transmit and receive power (8.2 mA TX at +6 dBm, 3.6 mA RX), 1.2 µA deep sleep mode power, and innovative low-power features such as RFSense, providing industry-leading energy efficiency to extend the lifespan of products with limited battery or energy harvesting options.
The Silicon Labs RS9116 Wireless Module is an ultra-low-power RF-certified Wi-Fi 4 SiP module (802.11 b/g/n) with an integrated antenna, supporting Bluetooth Low Energy, Bluetooth Classic, and secure network protocol stacks, all in a compact size of 4.63 x 7.90 x 0.9 mm. The RS9116 wireless module is available in single and dual-band versions, offering a comprehensive multi-protocol wireless connectivity solution, including Wi-Fi and dual-mode Bluetooth 5. The wireless module features power-optimized performance, delivering high data throughput and extended range, and is FCC, IC, and ETSI/CE certified.
The SiWx917 Wi-Fi 6 and Bluetooth Low Energy 5.4 Wireless SoC is a SoC that supports low-power Wi-Fi 6 and Bluetooth Low Energy, suitable for energy-efficient smart devices, with up to 8 MB of flash memory and external PSRAM. The SiWx917 SoC is Silicon Labs’ lowest-power Wi-Fi 6 SoC, ideal for ultra-low-power IoT wireless devices using Wi-Fi®, Bluetooth, Matter, and IP networks for secure cloud connectivity, making it perfect for developing devices powered by long-lasting batteries.
The SiWx917 SoC includes an ultra-low-power Wi-Fi 6 and Bluetooth Low Energy 5.4 wireless CPU subsystem, an integrated microcontroller (MCU) application subsystem, security features, peripherals, and a power management subsystem, all integrated into a 7 x 7 mm QFN package. The wireless subsystem comprises a multi-threaded processor running at up to 160 MHz, baseband digital signal processing, analog front end, 2.4 GHz RF transceiver, and integrated power amplifier.
The SiWx917’s application subsystem consists of an ARM® Cortex®-M4F running up to 180 MHz, embedded SRAM, flash memory, and a sensor hub. The ARM® Cortex®-M4F is dedicated to peripherals and application-related processing, while the network wireless processor runs the wireless and network protocol stacks on independent threads, providing a fully integrated solution for various embedded wireless IoT applications. Target applications include smart homes, consumer health and wearables, healthcare, industrial, retail, smart buildings and cities, and asset tracking.
Conclusion
In the rapidly evolving tech environment today, developing smart devices is not just about technological innovation but also a crucial pathway to meeting user needs and enhancing quality of life. In the process of designing smart devices, designers can leverage advanced sensor technologies, big data analytics, and artificial intelligence. These modern technologies enable smart devices to achieve more efficient and intelligent interaction methods, offering users a more convenient and comfortable living experience. Silicon Labs provides comprehensive product solutions and technical support services, making it one of the best partners for developing related products.