IoT Smart Water Care System Leverages Nordic’s BLE SoC

Nordic Semiconductor has announced that ConnectedYard has selected Nordic’s nRF51822 Bluetooth Low Energy (BLE) SoC to provide the wireless connectivity for pHin, a smart water care solution designed to simplify the care and maintenance of backyard swimming pools and hot tubs. pHin combines an nRF51822 SoC- and Wi-Fi-enabled smart monitor and smartphone app that monitors water chemistry and temperature around the clock and notifies customers when they need to take action.
The pHin Smart Monitor floats in the pool or hot tub and continuously monitors water temperature and water chemistry—including pH and oxidation reduction potential (ORP)—and then wirelessly sends the water chemistry data over the Nordic SoC-enabled Bluetooth LE connection to the pool owner’s Bluetooth 4.0 (or later) smartphone and the ‘pHin WiFi bridge’. The data is also available via the pHin Partner Portal, which allows retailers, service technicians, and pool builders to remotely monitor water conditions and provides features that help drive consumers back to their local retailer for chemicals and other products. pHin uses a coin cell battery to achieve over two years of battery life between replacement, thanks in part to the ultra low power consumption of the nRF51822 SoC.

Nordic’s nRF51822 is ideally suited for Bluetooth LE and 2.4GHz ultra low power wireless applications. The nRF51822 is built around a 32-bit Arm® Cortex M0 CPU, 2.4GHz multiprotocol radio, and 256kB/128kB Flash and 32kB/16kB RAM. The SoC is supplied with Nordic’s S130 SoftDevice, a Bluetooth 4.2 qualified concurrent multi-link protocol stack. Nordic’s software architecture includes a clear separation between the RF protocol software and the application code, simplifying development for ConnectedYard’s engineers and ensuring the SoftDevice doesn’t become corrupted when developing, compiling, testing and verifying application code.

Nordic Semiconductor | www.nordicsemi.com

Low-Power Wireless MCUs Provide Real-Time Performance

STMicroelectronics (ST) has announced its latest Bluetooth offering, its STM32WBx5 dual-core wireless MCUs. The devices come with Bluetooth 5, OpenThread and ZigBee 3.0 connectivity combined with ultra-low-power performance. Fusing features of ST’s STM32L4 Arm Cortex-M4 MCUs and in-house radio managed by a dedicated Cortex-M0+, the STM32WBx5 is power-conscious yet capable of concurrent wireless-protocol and real-time application execution. It is well suited to remote sensors, wearable trackers, building automation controllers, computer peripherals, drones and other IoT devices.
Security features of the STM32WBx5 MCUs include Customer Key Storage (CKS), Public Key Authorization (PKA), and encryption engines for the radio MAC and upper layers. The MCUs have up to 1 MB of on-chip flash and a Quad-SPI port for efficient connection to external memory, if needed. Additional features include crystal-less Full-Speed USB, 32 MHz RF oscillator with trimming capacitors, a touch-sense controller, LCD controller, analog peripherals and multiple timers and watchdogs. The balun for antenna connection is also integrated.

Leveraging ultra-low-power technologies of the STM32L4 line, STM32WBx5 MCUs feature multiple power-saving modes including 13 nA shutdown mode, adaptive voltage scaling, and the adaptive real-time (ART) accelerator to maximize energy efficiency and ensure long-lasting performance in self-powered applications. The integrated radio transmitter is optimized for high RF performance and low power consumption to maximize battery runtime. The RF output power is programmable up to +6 dBm in 1 dB increments, and the MCU draws only 5.2 mA when transmitting at 0 dB. Receive sensitivity is -96 dBm for BLE communication at 1mbps. Designed for a link budget of 102 dB, the radio ensures robust communication over long connection distances and includes support for an external Power Amplifier (PA).

STMicroelectronics | www.st.com

 

8-Bit MCU Marries Ultra Low Power and Rich Analog I/O

STMicroelectronics has announced STM8L050, a low power 8-bit MCU that embeds rich analog peripherals, a DMA controller and separated data EEPROM—all in an inexpensive SO-8 package with up to six user I/Os. Built around ST’s STM8 core running at up to 16 MHz, the STM8L050 is well suited for resource-constrained products like industrial sensors, toys, access cards, e-bike controllers, home-automation or lighting products, smart printer cartridges or battery chargers.

The integrated DMA (Direct Memory Access) controller speeds application performance by streamlining data transfers between peripherals and memory, or from memory to memory, ultimately saving power consumption. The 256 bytes of separated EEPROM allows applications to store important program data when the MCU is powered down, while allowing maximum utilization of flash for code storage.

Alongside two comparators, the STM8L050 has a 4-channel 12-bit analog-digital converter (ADC) and a low-power real-time clock (RTC) with programmable alarm and periodic wakeups, allowing designers to minimize external analog components. In addition, support for either an external or internal clock at up to 16 MHz further enhances flexibility to balance performance with bill-of-materials (BOM) savings.

Other features include 8 KB of on-chip flash memory, 1 KB of RAM, two 16-bit timers, one 8-bit timer, and popular connectivity and debug interfaces including SPI, I2C, UART and SWIM. The STM8L050 provides power-saving modes that cut current to as little as 350 nA, and operates over a wide voltage range from 3.6 V down to 1.8 V. The MCUs are fully specified from -40°C to 125°C, ensuring robustness and reliability in demanding applications such as industrial controls or lighting products.

The STM8L050J3 is in production now, and available in the SO-8 package, priced from $0.25 for orders of 10,000 pieces.

STMicroelectronics | www.st.com

Tailored Solutions Tackle Design Needs for Wearables

Low Power Priorities

For wearable devices, every drop of power is precious. That’s driving designers of these embedded systems to attack the power challenge from multiple angles. Fortunately, a slew of analog, power and system ICs have emerged that address the wearable market’s particular needs.

By Jeff Child, Editor-in-Chief

While power is an important issue in any embedded system design, it’s especially critical in wearable devices. Today’s generation of wearable electronics require longer battery lives, more functionality and better performance—all in extremely small form factors. Wearables comprise a wide variety of products including smartwatches, physical activity monitors, heart rate monitors, smart headphones and more.
Today’s wearable electronic devices share some common design priorities. First, they have an extremely low budget for power consumption. And because they’re not suited to being powered by replaceable batteries, they usually require a way for the unit to be recharged. Meanwhile, most modern wearables require some kind of wireless connectivity.

Feeding those needs, chip vendors—primarily from the microcontroller (MCU) and analog sectors—over the past 12 months have announced a generous mix of solutions to help keep power consumption low, to aid recharging and to enable new capabilities while maintaining narrow power constraints. Chip and platform solutions aimed at wearables span the range from specialized power management ICs (PMICs), data converters and power regulator chips, to wireless charging solutions and even complete reference design platforms specially for wearables.

Wrist-Worn Health Gear

Wearables have evolved from being more than just fun devices for health and fitness. Using sophisticated sensors and other capabilities, devices are being designed to do virtual care monitoring, assess chronic conditions and evaluate overall well-being. Along just those lines, in September Maxim Integrated announced its Health Sensor Platform 2.0 (HSP 2.0) (Figure 1). This wrist-worn platform can be used for rapid prototyping, evaluation and development. It provides the ability to monitor electrocardiogram (ECG), heart rate and body temperature from a wrist-worn wearable, saving up to six months in development time, according to Maxim.

Figure 1
The Health Sensor Platform 2.0 is a wrist-worn platform that can be used for rapid prototyping, evaluation and development. It provides the ability to monitor electrocardiogram (ECG), heart rate and body temperature from a wrist-worn wearable.

In the past, system developers have found it challenging to derive precise ECG monitoring from the wrist—most alternatives require a wearable chest strap. Getting accurate body temperature typically requires using a thermometer at another location. Maxim has overcome these challenges in the HSP 2.0. by using its proprietary sensor and health monitoring technology.

Enclosed in a watch casing, the wrist-based form factor enables HSP 2.0 to provide basic functionality out of the box, with body-monitoring measurements starting immediately. Data can be stored on the platform for patient evaluation or streamed to a PC for analysis later. Unlike other wearables, the data measurements collected by the HSP 2.0 can be owned by the wearer. This alleviates data privacy concerns and enables users to conduct their own data analysis. Also, because HSP 2.0 is an open platform, designers can evaluate their own algorithms on the board. In addition, the modular format is future proof to quickly accommodate new sensors over time.

HSP 2.0 includes the following Maxim chips: the MAX32630 DARWIN low-power MCU for wearables; the MAX32664 ultra-low-power biometric sensor hub with embedded heart-rate algorithm; the MAX20303 PMIC; the MAX30205 human body temperature sensor with ±0.1°C accuracy; the MAX30001 single-channel integrated biopotential and bioimpedance analog front-end (AFE) solution; and the MAX86141 optical pulse oximeter and heart-rate sensor.

Energy Controller for Wearables

For its part, Renesas Electronics has been working on meeting extreme low power demands by applying innovations in semiconductor process development. In November the company unveiled an innovative energy-harvesting embedded controller that can eliminate the need to use or replace batteries in a device. Developed based on Renesas’ SOTB (silicon-on-thin-buried-oxide) process technology, the new embedded controller achieves extreme reduction in both active and standby current consumption. The extreme low current levels of the SOTB-based embedded controller enables system designers to completely eliminate the need for batteries in some of their products through harvesting ambient energy sources such as light, vibration and flow (Figure 2).

Figure 2
The extreme low current levels of the SOTB-based embedded controller enables system designers to completely eliminate the need for batteries in some of their products through harvesting ambient energy sources such as light, vibration and flow.

Although the solution was developed with IoT devices in mind, the controller is more broadly aimed at what they call the new market of maintenance-free, connected IoT sensing devices with endpoint intelligence. This includes health and fitness apparel, shoes, wearables, smart watches and drones. Renesas’ first commercial product using SOTB technology, the R7F0E embedded controller, is a 32-bit, Arm Cortex-based embedded controller. The device is capable of operating up to 64 MHz for rapid local processing of sensor data and execution of complex analysis and control functions.

The R7F0E consumes just 20 μA/MHz active current, and only 150 nA deep standby current, approximately one-tenth that of conventional low-power MCUs. According to the company, samples of the new R7F0E embedded controller are available now for beta customers, and samples are scheduled to be available for general customers from July 2019. Mass production is scheduled to start from October 2019.

LDO Regulator for Wearables

Achieving longer battery lives is a problem that can be attacked from many angles. Power regulator electronics are among those. With that in mind, Microchip Technology in October introduced a linear Low Dropout (LDO) regulator that extends battery life in portable devices up to four times longer than traditional ultra-low quiescent (IQ) LDOs. With an ultra-low IQ of 250 nA versus the approximately 1 µA operation of traditional devices, the MCP1811 LDO reduces quiescent current to save battery life, enabling end users to recharge or replace batteries less often (Figure 3).

Figure 3
With an ultra-low IQ of 250 nA versus the approximately 1 µA operation of traditional devices, the MCP1811 LDO regulator saves battery life, enabling end users to recharge or replace batteries less often.

Well suited for IoT and battery-operated applications such as wearables, remotes and hearing aids, the LDO reduces power consumption in applications by minimizing standby or shutdown current. Reducing standby power consumption is critical in remote, battery-powered sensor nodes, where battery replacement is difficult and operating life requirements are high. Available in package options as small as 1 mm x 1 mm, the MCP1811 consumes minimal board space to meet the needs of today’s compact portable electronic designs. Depending on the application and number of LDOs, designers can take advantage of the extra board space with a larger battery to further increase battery life.

An additional benefit the MCP1811 offers is faster load line and transient response when compared to other ultra-low IQ LDOs. Faster response times can accelerate wake-up speed in devices such as monitors or sensors that require immediate attention. Faster transient response can help designers avoid undervoltage and overvoltage lockout measures used in sensitive applications where transient spikes can lead to catastrophic results.

Secure Payments with Wearables

An important capability in a certain class of wearables is the ability to support electronic retail transactions directly from the wearable device. While this is arguably a whole separate technology category in itself, we’ll touch on a couple developments here. In November, Infineon Technologies announced an EMV-based payment solution for key chains, rings, wristbands, bracelets and other wearable devices.

The SECORA Pay W for Smart Payment Accessories (SPA) combines an EMV chip with the card operating system, payment applet as well as the antenna directly on the unit. As a turnkey solution it allows card vendors, device manufacturers, financial institutions or event organizers to quickly and cost-efficiently introduce fashion accessories for payment and even access.

Infineon’s SECORA Pay solutions portfolio comprises the SECORA Pay S for standard Visa and MasterCard payment cards, SECORA Pay X for applications with extended features such as multi-application, national debit and white label schemes or access management and SECORA Pay W for payment accessories. All SECORA turn-key solutions are pre-certified by Mastercard and Visa and will accelerate the deployment of contactless payment. The EMV Chip Specifications (www.emvco.com) define globally valid requirements for chip-based payment solutions and acceptance terminals. They enable secure contact- and contactless applications and the use of other emerging payment technologies.

Complete Payment SoC

Likewise a player in the contactless transaction market, STMicroelectronics (ST) back in October announced teaming up with Fidesmo to create a turnkey active solution for secure contactless payments on smart watches and other wearable technology. The complete payment system-on-chip (SoC) is based on ST’s STPay-Boost IC, which combines a hardware secure element to protect transactions and a contactless controller featuring proprietary active-boost technology that maintains reliable NFC connections even in devices made with metallic materials. Its single-chip footprint fits easily within wearable form factors (Figure 4).

Figure 4
The STPay-Boost IC combines a hardware secure element to protect transactions and a contactless controller featuring proprietary active-boost technology that maintains reliable NFC connections even in devices made with metallic materials. Its single-chip footprint fits easily within wearable form factors.

ST’s proprietary NFC-boosting active load modulation technology simplifies RF design and accelerates time to market by ensuring superior performance with little or no circuit optimization needed. A small-size antenna can sustain robust and reliable wireless connection, permitting smaller overall product dimensions and lower power consumption resulting in longer battery life.

Fidesmo’s MasterCard MDES tokenization platform completes the solution by allowing the user to load the personal data needed for payment transactions. Convenient Over-The-Air (OTA) technology makes personalization a simple step for the user without any special equipment. Kronaby, a Sweden-based hybrid smartwatch maker, has embedded the STPay-Boost chip in its portfolio of men’s and women’s smart watches that offer differentiated features such as freedom from charging and filtered notifications. The SoC with Fidesmo tokenization enables Kronaby watches to support a variety of services such as payments, access control, transportation and loyalty rewards.

Data Converters

Data converters also have role to play in efforts to meet the extreme low power needs of wearable devices. Along such lines, in December Texas Instruments (TI) introduced four tiny precision data converters (Figure 5). The new data converters enable designers to add more intelligence and functionality, while shrinking system board space. The DAC80508 and DAC70508 are eight-channel precision digital-to-analog converters (DACs) that provide true 16- and 14-bit resolution, respectively.

Figure 5
The DAC80508 and DAC70508 are eight-channel precision DACs that provide true 16- and 14-bit resolution, respectively. The ADS122C04 and ADS122U04 are 24-bit precision ADCs that feature a two-wire, I2C-compatible interface and a two-wire, UART-compatible interface, respectively.

The ADS122C04 and ADS122U04 are 24-bit precision analog-to-digital converters (ADCs) that feature a two-wire, I2C-compatible interface and a two-wire, UART-compatible interface, respectively. The devices are optimized for a variety of small-size, high-performance or cost-sensitive electronics applications such as wearables.

Both DACs include a 2.5-V, 5-ppm/°C internal reference, eliminating the need for an external precision reference. Available in a 2.4-mm-by-2.4-mm die-size ball-grid array (DSBGA) package or wafer chip-scale package (WCSP) and a 3-mm-by-3-mm quad flat no-lead (QFN)-16 package, these devices are up to 36% smaller than the competition, says TI. Meanwhile, the tiny, 24-bit precision ADCs are available in 3-mm-by-3-mm very thin QFN (WQFN)-16 and 5-mm-by-4.4-mm thin-shrink small-outline package (TSSOP)-16 options. The two-wire interface requires fewer digital isolation channels than a standard serial peripheral interface (SPI), reducing the overall cost of an isolated system. These precision ADCs eliminate the need for external circuitry by integrating a flexible input multiplexer, a low-noise programmable gain amplifier and other circuitry.

Memory Innovations

Among the latest innovations aimed at wearables from Cypress Semiconductor is an FRAM (ferroelectric random access memory)-based data logging solution. In November, Cypress introduced a nonvolatile data-logging solution with ultra-low power consumption. This solution is well suited for portable medical and wearable devices that demand nonvolatile memories to continuously log an increasing amount of user and sensor data while using as little power as possible.

Cypress’ Excelon LP FRAM is an energy-efficient device that provides instant-write capabilities with virtually unlimited endurance (Figure 6). This enables wearable systems to perform mission-critical data logging requirements while maximizing battery life. The Excelon LP series is available in a low-pin-count, small-footprint package that is suited for space-constrained, wearable applications.

Figure 6
The Excelon LP FRAM provides instant-write capabilities with virtually unlimited endurance. This enables wearable systems to perform mission-critical data logging requirements while maximizing battery life.

The Excelon LP series offers 4-Mb and 8-Mb industrial and commercial-grade densities with 50 MHz and 20 MHz Serial Peripheral Interface (SPI) performance. The series reduces power consumption with 100 nA hibernate and 1 µA standby modes that greatly improve a battery-powered product’s user experience by extending system operating time. The device’s inherent instant writes also eliminate power failure “data-at-risk” due to volatile data buffers in legacy memories. The family features wide voltage operation from 1.71 V to 3.6 V and is available in RoHS-compliant industry-standard packages that are pin compatible with EEPROMs and other nonvolatile memories. Excelon LP F-RAMs provide 1,000-trillion (1015) read/write cycle endurance with 10 years of data retention at 85°C or 151 years at 65°C.

Charging Wearables

A common aspect of wearable devices is that they tend not to be suited for replaceable batteries. As a result, they typically need to be recharged. Wireless (cordless) battery charging is beginning to take hold as a solution. Feeding such needs, in October Analog Devices announced its Power by Linear LTC4126 as an expansion of its offerings in wireless battery charging. The LTC4126 combines a wireless powered battery charger for Li-Ion cells with a high efficiency multi-mode charge pump DC-DC converter, providing a regulated 1.2 V output at up to 60 mA (Figure 7).

Figure 7
The LTC4126 combines a wireless powered battery charger for Li-Ion cells with a high efficiency multi-mode charge pump DC-DC converter, providing a regulated 1.2 V output at up to 60 mA.

Charging with the LTC4126 allows for a completely sealed end product without wires or connectors and eliminates the need to constantly replace non-rechargeable (primary) batteries. The efficient 1.2 V charge pump output features pushbutton on/off control and can directly power the end product’s ASIC. This greatly simplifies the system solution and reduces the number of necessary external components. The device is ideal for space-constrained low power Li-Ion cell powered wearables such as hearing aids, medical smart patches, wireless headsets and IoT devices.

The LTC4126, with its input power management circuitry, rectifies AC power from a wireless power receiver coil and generates a 2.7 V to 5.5 V input rail to power a full-featured constant-current/constant-voltage battery charger. Features of the battery charger include a pin selectable charge voltage of 4.2 V or 4.35 V, 7.5 mA charge current, automatic recharge, battery temperature monitoring via an NTC pin, and an onboard 6-hour safety charge termination timer. Low battery protection disconnects the battery from all loads when the battery voltage is below 3.0 V. The LTC4126’s charge pump switching frequency is set to 50 kHz/75 kHz to keep switching noise out of the audible range, ideal for audio related applications such as hearing aids and wireless headsets. The IC is housed in a compact, low profile (0.74 mm) 12-lead 2 mm × 2 mm LQFN package. The device is guaranteed for operation from –20°C to 85°C in E-grade.

Kit for Wireless Charging

Also facilitating building wireless chargers for wearables, ST for its part offers a kit-level solution. The ST plug-and-play wireless battery-charger development kit (STEVAL-ISB045V1) lets users quickly build ultra-compact chargers up to 2.5 W with a space-saving 20 mm-diameter coil, for charging small IoT devices and wearables such as smart watches, sports gear or healthcare equipment (Figure 8).

Figure 8
The ST plug-and-play wireless battery-charger development kit lets users quickly build ultra-compact chargers up to 2.5 W with a space-saving 20 mm-diameter coil, for charging small IoT devices and wearables such as smart watches, sports gear or healthcare equipment.

Built around the STWBC-WA wireless charging-transmitter controller, the kit comprises a charging base unit containing a transmitter board with the 20 mm coil already connected and ready to use. Getting started is easy, using the PC-based STSW-STWBCGUI software to configure the STWBC-WA and monitor runtime information such as power delivered, bridge frequency, demodulation quality and protocol status. The kit includes a dongle for running the GUI. The supporting ecosystem includes certified reference boards, software and detailed documentation to help developers quickly design chargers for wearables.

The STWBC-WA controller chip contains integrated drivers and natively supports full-bridge or half-bridge topologies for powering the antenna. The half-bridge option allows charging up to 1 W with a smaller-diameter coil for an even more compact form factor. The chip supports all standard wireless-charging features, including Foreign Object Detection (FOD) and active presence detection for safe charging, and uses digital feedback to adapt the transmitted power for optimum efficiency at all load conditions. Two firmware options give users the choice of a fast turnkey solution or customizing the application using APIs to access on-chip peripherals including an ADC, a UART and GPIOs.

Clearly there are many facets and angles to address the low power needs of wearables. As demands for more functionality rise, system developers will need to remain ever mindful of keeping battery life at the same lengths or longer. Fortunately, there seems to be no stopping the innovation among chip vendors targeting this growing wearables market.

RESOURCES

Analog Devices | www.analog.com
Cypress Semiconductor | www.cypress.com
Infineon Technologies | www.infineon.com
Maxim Integrated | www.maximintegrated.com
Microchip Technology | www.microchip.com
Renesas Electronics America | www.renesas.com
STMicroelectronics | www.st.com
Texas Instruments | www.ti.com

This article appeared in the March 344 issue of Circuit Cellar

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Firms Team Up to Provide End-to-End LoRa Security Solution

Microchip Technology, in partnership with The Things Industries, has announced the what it claims is industry’s first end-to-end security solution that adds secure, trusted and managed authentication to LoRaWAN devices at a global scale. The solution brings hardware-based security to the LoRa ecosystem, combining the MCU- and radio-agnostic ATECC608A-MAHTN-T CryptoAuthentication device with The Things Industries’ managed join servers and Microchip’s secure provisioning service.

The joint solution significantly simplifies provisioning LoRaWAN devices and addresses the inherent logistical challenges that come with managing LoRaWAN authentication keys from inception and throughout the life of a device. Traditionally, network and application server keys are unprotected in the edge node, and unmonitored, as LoRaWAN devices pass through various supply chain steps and are installed in the field.

The Common Criteria Joint Interpretation Library (JIL) “high”-rated ATECC608A comes pre-configured with secure key storage, keeping a device’s LoRaWAN secret keys isolated from the system so that sensitive keys are never exposed throughout the supply chain nor when the device is deployed. Microchip’s secure manufacturing facilities safely provision keys, eliminating the risk of exposure during manufacturing. Combined with The Things Industries’ agnostic secure join server service to the LoRaWAN network and application server providers, the solution decreases the risk of device identity corruption by establishing a trusted authentication when a device connects to a network.

Similar to how a prepaid data plan works for a mobile device, each purchase of an ATECC608A-MAHTN-T device comes with one year of managed LoRaWAN join server service through The Things Industries. Once a device identifies itself to join a LoRaWAN network, the network contacts The Things Industries join server to verify that the identity comes from a trusted device and not a fraudulent one. The temporary session keys are then sent securely to the network server and application server of choice. The Things Industries’ join server supports any LoRaWAN network, from commercially operated networks to private networks built on open-source components. After the one-year period, The Things Industries provides the option to extend the service.

Microchip and The Things Industries have also partnered to make the onboarding process of LoRaWAN devices seamless and secure. LoRaWAN device identities are claimed by The Things Industries’ join server with minimal intervention, relieving developers from needing expertise in security. Customers can not only choose any LoRaWAN network but can also migrate to any other LoRaWAN join server by rekeying the device. This means there is not a vendor lock-in and customers have full control over where and how the device keys are stored.

The ATECC608A is agnostic and can be paired with any MCU and LoRa radio. Developers can deploy secure LoRaWAN devices by combining the ATECC608A with the SAM L21 MCU, supported by the Arm Mbed OS LoRaWAN stack, or the recently-announced SAM R34 System-in-Package with Microchip’s LoRaWAN stack. For rapid prototyping, designers can use the CryptoAuthoXPRO socket board and The Things Industries provisioned parts in samples with the SAM L21 Xplained Pro (atsamd21-xpro) or SAM R34 Xplained Pro (DM320111).

The ATECC608A-MAHTN-T device for The Things Industries, including the initial year of prepaid TTN service, is available in volume production for $0.81 each in 10,000-unit quantities.

Microchip Technology | www.microchip.com

 

Nordic Semi’s BLE SoC Selected for Ultra Low Power IoT Module

Nordic Semiconductor has announced that Nanopower has selected Nordic’s nRF52832 Bluetooth Low Energy (Bluetooth LE) System-on-Chip (SoC) to provide the wireless connectivity for its nP-BLE52 module, designed for developers of IoT applications with highly restricted power budgets.

The nP-BLE52 module employs a proprietary power management IC—integrated alongside Nordic’s nRF52832 Wafer-Level Chip Scale Package (WL-CSP) SoC in a System-in-Package (SiP)—which enables it to cut power to the SoC, putting it in sleep mode, before waking it up a pre-set time and in the same state as before it was put to sleep. In doing so the SoC’s power consumption in sleep mode is reduced to 10 nA, making it well suited for IoT applications where battery life is critical by potentially increasing cell lifespan 10x.

In active mode, the nRF52832 SoC runs normally. The SoC has been engineered to minimize power consumption with features such as the 2.4GHz radio’s 5.5mA peak RX/TX currents and a fully-automatic power management system. Once the Nordic SoC has completed its tasks, it instructs the nP-BLE52 to put it to sleep and wake it up again at the pre-set time. The nP-BLE52 then stores the Nordics SoC’s state variables and waits until the nRF52832 SoC needs to be powered up again. On wake-up, the device uploads the previous state variables, allowing the Nordic SoC to be restored to the same operational state as before the power was cut. The SoC’s start-up is much more rapid than if it was activated from a non-powered mode.

The nP-BLE52 module also features a low power MCU which can be set to handle external sensors and actuators when the Nordic chip is switched off. In this state, the module still monitors sensors and buffer readings and can trigger wake-ups if these readings are above predetermined thresholds, while consuming less than 1 uA. The nP-BLE52 also integrates an embedded inertial measurement unit (IMU).

The module’s power management is controlled through a simple API, whereby the user can predetermine the duration of the Nordic SoC’s sleep mode, set the wake-up time and date parameters, and select pins for other on/off triggers.

The module offers IoT developers several advantages, either extending battery life and/or reducing the size of the battery required to power the application thereby reducing the end-product footprint. Longer battery life also reduces or eliminates battery swaps and enables the developer to better adjust for remaining useful battery life as the battery discharges. The module is suitable for any battery-powered device which is not required to be constantly active, for example asset tracking, remote monitoring, beacons, and some smart-home applications.

The nRF52832 WL-CSP SoC measures just 3.0 mm by 3.2mm while offering all the features of the conventionally-packaged chip. The nRF52832 is a powerful multiprotocol SoC ideally suited for Bluetooth LE and 2.4 GHz ultra low-power wireless applications. It combines an 64 MHz, 32-bit Arm Cortex M4F processor with a 2.4 GHz multiprotocol radio (supporting Bluetooth 5, ANT, and proprietary 2.4 GHz RF software) featuring -96dB RX sensitivity, with 512kB Flash memory and 64kB RAM.

The WL-CSP SoC is supplied with Nordic’s S132 SoftDevice, a Bluetooth 5-certifed RF software protocol stack for building advanced Bluetooth LE applications. The S132 SoftDevice features Central, Peripheral, Broadcaster, and Observer Bluetooth LE roles, supports up to twenty connections, and enables concurrent role operation. Nordic’s unique software architecture provides clear separation between the RF protocol software and the developer’s application code, easing product development.

Nordic Semiconductor | www.nordicsemi.com

Secure MCU Family Targets Low Power, Small Footprint Designs

STMicroelectronics has added the new STM32G0 microcontrollers (MCUs) to the STM32 family. The new G0 series targets entry-level applications that require greater energy efficiency, functionality, security, and value, in a smaller footprint. Extremely flexible packaging and memory options enable designers to do more within less space, and save cost. A new power-distribution architecture reduces external power and ground connections to just a single pair of pins, allowing more of the package pins—a precious resource in many embedded projects—to be allocated for user connectivity.

In addition, ST is making large memory densities available in small and economical low-pin-count packages. On top of this, the new generation features power-saving innovations that trim consumption close to that of specialized ultra-low-power devices.

To provide robust security for today’s connected devices, the STM32G0 series introduces a variety of hardware-based features including memory protection to support secure boot. Some devices in the series add to these features an AES-256 hardware cryptographic accelerator with a true random number generator (TRNG) to aid encryption.

Another valuable feature that anticipates a growing need is support for the latest USB Type-C specifications that allow easy, high-speed connectivity and battery charging, including Power Delivery version 3.0.

The STM32G0 series is based on the Arm Cortex-M0+ core, which is conceived to deliver sharp performance within a tight power budget. It targets fast-evolving products in the connected world, including smartphones, smart kitchen equipment, and appliances, air conditioning, consumer or industrial motor controls, advanced user interfaces, IoT devices, rechargeable connected devices, drones, lighting systems and more.

Package options are available from 8-pin, enabling developers to easily upgrade aging 8-bit MCU designs, to 100-pin. Flash from 16 KB to 512 KB, with 512 KB available in packages as small as 32-pin, enables more sophisticated applications on small, low-cost products.

The maximum CPU frequency of 64 MHz permits high execution speeds, compared to typical entry-level MCUs. On the other hand, extremely flexible clock configuration allows users to tailor performance within the available power budget. The internal clock is remarkably stable and comparable to high-end devices, being accurate to within ±1% from 0-85°C and ±2% over the wider range from -40°C to 125°C. This not only saves the board space and pins needed to connect a dedicated external timing device, but also can trim at least 10 cents from the bill of materials.

The STM32G0 series is extremely efficient, running at less than 100µA/MHz in run mode, and provides multiple reduced-power operating modes to save energy and extend battery runtimes. Devices draw as little as 3-8µA in stop mode with the real-time clock (RTC) running, and just 500 nA in standby with RTC (all at 3.0V, 25°C).

Moreover, peripherals are upgraded to enhance performance, speed, and accuracy. The devices feature a 12-bit 2.5 MSPS ADC, with hardware oversampling for 16-bit precision. There is also a 2-channel DAC, fast comparators, and high-accuracy timers with 7.8 ns resolution.

In addition to permitting extra user-assignable I/Os, the internal (ST-patented) power-distribution scheme also helps save BoM costs by reducing the number of external power-supply decoupling components.

Enhanced internal prevention of electromagnetic susceptibility (EMS) is yet another feature that saves board space and BoM costs. Protection against fast-transient bursts above 4.5kV, in accordance with IEC 61000-4-4, relaxes the demands for surrounding filtering components and eases board layout. For product-development teams, the ability to easily ensure good electromagnetic behavior facilitates EMC certifications for faster time to market.

ST is planning several STM32G0 lines, including the STM32G071 and similar STM32G081 with hardware cryptographic enhancement. There are also Value Line STM32G070 devices for mass-market applications. Pricing starts from $0.69 for the STM32G070CBT6 Value Line MCU in a 48-pin package, with 128 KB flash, for orders of 10,000 pieces.

STMicroelectronics | www.st.com

MCU Family Serves Up Ultra-Low Power Functionality

STMicroelectronics has released its STM32L0x0 Value Line microcontrollers that provide an additional, low-cost entry point to the STM32L0 series The MCUs embed the Arm Cortex -M0+ core. With up to 128 KB flash memory, 20 KB SRAM and 512 byte true embedded EEPROM on-chip the MCUs save external components to cut down on board space and BOM cost. In addition to price-sensitive and space-constrained consumer devices such as fitness trackers, computer or gaming accessories and remotes, the new STM32L0x0 Value Line MCUs are well suited for personal medical devices, industrial sensors, and IoT devices such as building controls, weather stations, smart locks, smoke detectors or fire alarms.
The devices leverage ST’s power-saving low-leakage process technology and device features such as a low-power UART, low-power timer, 41µA 10 ksample/s ADC and wake-up from power saving in as little as 5µs. Designers can use these devices to achieve goals such as extending battery runtime without sacrificing product features, increasing wireless mobility, or endowing devices like smart meters or IoT sensors with up to 10-year battery-life leveraging the ultra-frugal 670 nA power-down current with RTC and RAM retention.

The Keil MDK-ARM professional IDE supports STM32L0x0 devices free of charge, and the STM32CubeMX configuration-code generator provides easy-to-use design analysis including a power-consumption calculator. A compatible Nucleo-64 development board (NUCLEO-L010RB) with Hardware Abstraction Layer (HAL) library is already available, to facilitate fast project startup.

The STM32L0x0 Value Line comprises six new parts, giving a choice of 16- KB, 64- KB, or 128- KB of flash memory, 128-byte, 256-byte or 512-byte EEPROM, and various package options. In addition, pin-compatibility with the full STM32 family of more than 800 part numbers offering a wide variety of core performance and integrated features, allows design flexibility and future scalability, with the freedom to leverage existing investment in code, documentation and tools.

STM32L0x0 Value Line microcontrollers are in production now, priced from $0.44 with 16-KB of flash memory and 128-byte EEPROM, for orders of 10,000 pieces. The unit price starting at $0.32 is available for high-volume orders.

STMicroelectronics| www.st.com

Fuel-Gauge ICs Target Mobile and Portable Devices

Maxim Integrated Products has announced the MAX17262 single-cell and MAX17263 single-/multi-cell fuel-gauge ICs. The MAX17262 features just 5.2 µA quiescent current, along with integrated current sensing. The MAX17263 features just 8.2 µA quiescent current and drives 3 to 12 LEDs to indicate battery or system status. Such LEDs are useful in rugged applications that do not feature a display.

According to the company, electronic products powered by small Li-ion batteries struggle to extend device run-times to meet user expectations. Factors such as cycling, aging and temperature can degrade Li-ion battery performance over time. Inaccurate state of charge (SOC) data from an unreliable fuel gauge forces the designer to increase the battery size or compromise the run-time by prematurely shutting the system down, even if there is usable energy available.
Such inaccuracies can contribute to a poor user experience due to abrupt shutdown or an increase in device charging frequency. Designers also strive to get their products to market quickly due to competitive demands. Maxim’s two new fuel-gauge ICs help designers meet end-user performance expectations and time-to-market challenges.

The MAX17262 and MAX17263 combine traditional coulomb counting with the novel ModelGauge m5 EZ algorithm for high battery SOC accuracy without requiring battery characterization. With their low quiescent current, both fuel-gauge ICs prevent current loss during long periods of device standby time, extending battery life in the process.

Both also have a dynamic power feature that enables the highest possible system performance without crashing the battery. In the MAX17262, an integrated Rsense current resistor eliminates the need to use a larger discrete part, simplifying and reducing the board design. In the MAX17263, the integrated, push-button LED controller minimizes battery drain and alleviates the microcontroller from having to manage this function.

The ICs provide accurate time-to-empty (1%) and time-to-full SOC data across a wide range of load conditions and temperatures, using the proven ModelGauge m5 algorithm. The ModelGauge m5 EZ algorithm eliminates the time-consuming battery-characterization and calibration process. A quiescent current of just 5.2 µA for the MAX17262 and 15/8.2 µA for MAX17263 extends run-time, Rsense current resistor (voltage and coulomb counting hybrid) reduces overall footprint and BOM cost, eases board layout

At 1.5 mm × 1.5 mm IC size, the MAX17262 implementation is 30% smaller in size compared to using a discrete sense resistor with an alternate fuel gauge; at 3 mm × 3 mm, MAX17263 is the smallest in its class for lithium-ion-powered devices. The single-/multi-cell MAX17263 also drives LEDs to indicate battery status on a pushbutton press or system status on system microcontroller commands

The MAX17262 is available at Maxim’s website for $0.95 (1000 pieces, FOB USA); the MAX17263 is also on the site for $1.49 (1,000 pieces). Both parts are also available via select authorized distributors. The MAX17262XEVKIT# evaluation kit is available for $60; the MAX17263GEVKIT# is available for $60.

Maxim Integrated | www.maximintegrated.com

Fuel-Gauge ICs Maximize Battery Runtimes for Devices

Maxim Integrated offers the MAX17260 and MAX17261 ModelGauge m5 EZ fuel gauges IC that are well suited for a broad range of Li-ion battery powered applications.  These battery characterization-free solutions provide high levels of accuracy while also offering small size and ease of design.

The MAX17260 and MAX17261, which feature the ModelGauge m5 EZ algorithm, provide a high level of accuracy in fuel gauging compared to competing solutions. This allows designers to maximize their devices’ runtime by preventing premature or sudden device shutdowns, while maintaining a smaller battery size. The fuel gauges, which are housed in an ultra-small 1.5 mm x 1.5 mm package, feature a very low quiescent current of 5.1 µA to minimize draining the battery during long periods of standby time. The products allow designs to be quickly done without battery characterization or calibration.
As devices have become more sophisticated with their feature offerings and increasing power density, designers are now challenged with achieving an enhanced user experience without compromising battery runtimes. There is also a huge market need for highly accurate fuel gauges, as less accuracy may introduce uncertainty that must be compensated with higher battery capacity and larger physical dimensions.

Accurate battery state of charge (SOC) prevents sudden crash and premature device shutdown; Provides easy to understand battery information for end users such as time to empty, time to full under current, as well as hypothetical load conditions; Dynamic power technology enables high system performance without crashing the battery and results in smaller battery size.

The very low quiescent current of 5.1µA of these chips prevent excessive energy loss during long periods of standby time. This battery characterization-free solution offers no battery size limit; MAX17260 offers a high-side Rsense option to simplify ground-plane design; MAX17261 offers a flexible switched resistor divider option to support any number of series cells (multi-cell batteries). The devices support small electronics with 1.5 mm x 1.5 mm wafer-level packaging (WLP) as well as 3 mm x 3 mm TDFN.

The MAX17260 is available for $0.93 (1000-up); MAX17261 is available for $1.22 (1000-up). MAX17260GEVKIT and MAX17261GEVKIT evaluation kits are available for $60.

Maxim Integrated | www.maximintegrated.com

GNSS Modules Enable Low-Power Location-Based IoT

Telit has announced the SE878Kx-A series of GPS and GNSS integrated antenna receiver modules for applications that require high performance, maximum reliability and low power consumption. Compatible with GPS, GLONASS, Beidou and Galileo, the new SE878K3-A and SE878K7-A enable device vendors to develop quickly and cost-effectively location-based IoT solutions for use in virtually any country worldwide.

The SE878Kx-A series supports dual internal-external antennas to ensure connectivity when one is broken or compromised, along with a SAW filter to maximize jamming immunity. These features make the modules well suited for mission-critical applications and other use cases where reliability is key, such as alarms, stolen cars or high-end asset tracking. The SE878Kx-A series also provides seamless integration with Telit’s cellular modules, including eCall/ERA-GLONASS compliant solutions, making them ideal for telematics applications such as fleet management, road tolling and in-vehicle navigation systems.

Telit | www.telit.com

Low-Power MCUs Extend Battery Life for Wearables

Maxim Integrated Products has introduced the ultra-low power MAX32660 and MAX32652 microcontrollers. These MCUs are based on the ARM Cortex-M4 with FPU processor and provide designers the means to develop advanced applications under restrictive power constraints. Maxim’s family of DARWIN MCUs combine its wearable-grade power technology with the biggest embedded memories in their class and advanced embedded security.

Memory, size, power consumption, and processing power are critical features for engineers designing more complex algorithms for smarter IoT applications. According to Maxim, existing solutions today offer two extremes—they either have decent power consumption but limited processing and memory capabilities, or they have higher power consumption with more powerful processors and more memory.
The MAX32660 (shown) offers designers access to enough memory to run some advanced algorithms and manage sensors (256 KB flash and 96 KB SRAM). They also offer excellent power performance (down to 50µW/MHz), small size (1.6 mm x 1.6 mm in WLP package) and a cost-effective price point. Engineers can now build more intelligent sensors and systems that are smaller and lower in cost, while also providing a longer battery life.

As IoT devices become more intelligent, they start requiring more memory and additional embedded processors which can each be very expensive and power hungry. The MAX32652 offers an alternative for designers who can benefit from the low power consumption of an embedded microcontroller with the capabilities of a higher powered applications processor.

With 3 MB flash and 1 MB SRAM integrated on-chip and running up to 120 MHz, the MAX32652 offers a highly-integrated solution for IoT devices that strive to do more processing and provide more intelligence. Integrated high-speed peripherals such as high-speed USB 2.0, secure digital (SD) card controller, a thin-film transistor (TFT) display, and a complete security engine position the MAX32652 as the low-power brain for advanced IoT devices. With the added capability to run from external memories over HyperBus or XcellaBus, the MAX32652 can be designed to do even more tomorrow, providing designers a future-proof memory architecture and anticipating the increasing demands of smart devices.

The MAX32660 and MAX32652 are both available at Maxim’s website and select authorized distributors. MAX32660EVKIT# and MAX32652EVKIT# evaluation kits are also both available at Maxim’s website.

Maxim Integrated | www.maximintegrated.com

The Dick Tracy Wristwatch TV

Input Voltage

–Jeff Child, Editor-in-Chief

JeffHeadShot

At my first technology editor job back in 1990, my boss at the time was obsessed with the concept of the Dick Tracy wristwatch. Dick Tracy was a popular comic strip that ran from the late 30s up until 1972. Now, let me be clear, even I’m not old enough to be from the era when Dick Tracy was part of popular culture. But my boss was. For those of you who don’t know, the 2-Way Wrist Radio was one of the comic strip’s most iconic items. It was worn by Tracy and members of the police force and in 1964 the 2-Way Wrist Radio was upgraded to a 2-Way Wrist TV. When chip companies came to visit our editorial offices—this is back when press tours were still a thing—in many editorial meetings with those companies, my boss would quite often ask the hypothetical question: “When are we going to get the Dick Tracy wristwatch?”

Confident that Moore’s Law would go on forever, semiconductor companies back then were always hungry to get their share of the mobile electronic device market—although the “device” of the day kept changing. My boss’s Dick Tracy wristwatch question was a clever way to spur discussion about chip integration, extreme low power, wireless communication and even full motion video. Full motion video on a mobile device in particular was a technology that many were skeptical could ever happen. In that early 90s period, the DRAM was the main driver of semiconductor process technology, and, in turn, the desktop PC was by far the dominant market for DRAMs. As a result, there was a tendency to view all future computing through the lens of the PC. It would be more than a decade later before flash memory surpassed DRAMs as the main driver of the chip business, and that was because the market size of mobile devices began to eclipse PCs.

As most of you know, Circuit Cellar has BYTE magazine as a part its origin story. Steve Ciarcia had a popular column called Circuit Cellar in BYTE magazine. When Steve founded this magazine three decades ago, he gave it the Circuit Cellar name. The April 1981 issue of BYTE magazine famously had a picture of basically a wristwatch with a CRT screen and keyboard with a mini-floppy disk being inserted into its side. That’s a vivid example that we humans are notoriously really bad at predicting what future technologies will look like. We have an inherent bias imposing what we have now on our view of the future.

Fast forward today and obviously we have the Dick Tracy Wristwatch and so much more—the Apple Watch being the most vivid example. Today’s wearable devices span across the consumer, fitness and medical markets and all need a mix of low-power, low-cost and high-speed processing. But even though technology has come a long way, the design challenges are still tricky. Wearable electronic devices of today all share some common aspects. They have an extremely low budget for power consumption, they tend not to be suited for replaceable batteries and therefore must be rechargeable. They also usually require some kind of wireless connectivity.

Today’s wearables including a variety of products including smartwatches, physical activity monitors, heart rate monitors, smart headphones and more. Microcontrollers for these devices have to have extremely low power and high integration. At the same time, power solutions servicing this market require mastery of low quiescent current design techniques and high integration. To meet those needs chip vendors—primarily from the microcontroller and analog markets—keep advancing solutions that consume extremely low levels and power and manage that power.

One amusing aspect of the Dick Tracy wristwatch was that it was referred as a 2-Way Radio (and later a 2-Way TV). With Internet connectivity, today’s smartwatches basically are connected to an infinite number of network nodes. I can’t claim to be a better predictor of the future than the editors of 1981’s BYTE. But now I need to come up with a new question to ask chip vendors, and I don’t know what the question should be. Perhaps: “When are we going to get the Star Wars holographic 3D image messaging system?”. And in wristwatch form please.

This appears in the May (334) issue of Circuit Cellar magazine

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Step-Down Converters Target Always-On Car Systems

Maxim Integrated Products has announced the ultra-compact, pin-compatible MAX20075 and MAX20076 step-down converters that enable system designers looking to create small and highly efficient 40-V load dump-tolerant applications. The MAX20075 and MAX20076 step-down converters offer low quiescent current (IQ) and feature integrated compensation. This enables minimal external components that can lead up to 50% savings in board space making them well-suited for always-on automotive applications.

According to Maxim Integrated, car customers expect always-on applications to bring them experiences richer and more compelling than ever before. However, car system designers are challenged with having to balance delivering advanced features with meeting size constraints, power-saving features and high efficiency.

The MAX20075 and MAX20076 in peak current mode draw just 3.5 µA in the low power operating mode, which is key to meeting the stringent OEM IQ consumption requirements of 100 µA per module. The converters enable low noise operation via pin-controlled spread spectrum and fixed 2.1 MHz operation to meet CISPR 25 Class 5 EMI compliance. Furthermore, added advantage of the 2.1 MHz operation and internal compensation is that it lowers the solution size and the bill of materials (BOM) compared to a non-synchronous device that operates in the AM band.

The MAX20075 and MAX20076 are available with a low minimum on-time mode operation, which allows the converters to support large input-to-output conversion ratios. For example, Vbatt input to Vout of less than 3 V at 2.1 MHz; this translates to not having to use a secondary supply, which reduces overall BOM cost by $0.30 to incorporate new functions into the design for greater flexibility. The MAX20075 and MAX20076 meet AEC-Q100, are available in a 3 mm x 3 mm TDFN package, and operate over the -40°C to +125°C temperature range.

Maxim Integrated | www.maximintegrated.com

MCUs Offer Capacitive Touch and Proximity Sensing

Bringing capacitive-sensing capabilities to cost-sensitive applications, Texas Instruments (TI) has announced an expansion of its MSP430 microcontroller (MCU) family with capacitive touch technology. Developers can use the new MSP430FR2512 and MSP430FR2522 MCUs with integrated capacitive touch to add as many as 16 buttons as well as proximity sensing capability to industrial systems, home automation systems, appliances, power tools, home entertainment, personal audio applications and more.

New MSP430 microcontrollers with capacitive touch technology provide a solution to applications exposed to electromagnetic disturbances, oil, water and grease. The MSP430FR2512 and MSP430FR2522 MCUs deliver International Electrotechnical Commission (IEC) 61000-4-6-certified capacitive sensing MCU-based solutions for applications exposed to electromagnetic disturbances, oil, water and grease. According to TI, the new MCUs offer five times lower power consumption than the competition, supporting proximity sensing and touch through glass, plastic and metal overlays.

TI’s CapTIvate technology adds the benefits of capacitive touch and proximity sensing to applications such as access control panels, cooktops, wireless speakers and power tools. Developers can quickly evaluate capacitive sensing for their applications with the new BOOSTXL-CAPKEYPAD BoosterPack plug-in module that is compatible with the CapTIvate programmer board (CAPTIVATE-PGMR) or TI LaunchPad development kits. The BoosterPack module joins a portfolio of MCUs, easy-to-use tools, software, reference designs and documentation in the CapTIvate Design Center and online CapTIvate technology guide. In addition, developers can find answers and support in the TI E2E Community to speed development with CapTIvate technology.

Production quantities of the MSP430FR2512 and MSP430FR2522 MCUs are available in a 20-pin very thin quad flat no lead (VQFN) package and a 16-pin thin shrink small outline package (TSSOP) starting at $0.69 in 1,000-unit quantities. The CapTIvate BoosterPack plug-in module (BOOSTXL-CAPKEYPAD) is available for $29.99.

Texas Instruments| www.ti.com