5G Modem for IoT and Wearable Devices

Although yet to become a commonplace scenario, we have been seeing and hearing about 5G quite often nowadays. For the most part, IoT devices and wearables are still in the realm of 4G LTE, while the rest of the industry has surged ahead. Now, Qualcomm is set to change that with the introduction of its Snapdragon X35 modem. With their new modem, Qualcomm aims to provide 5G support to these small devices. They are calling this technology 5G NR-Light, because of its reduced capability. According to the manufacturers, X35 modems will have a maximum downlink speed of around 220 Mbps and an uplink speed of around 100 Mbps.

Qualcomm claims their Snapdragon X35 will bring several breakthroughs in the world of 5G. Not only is the design of the world’s first 5G NR-Light modem cost-effective, but its streamlined form factor also leads to power efficiency. In addition, the company has designed the modem with optimized thermal performance. The company expects the Snapdragon X35 to power the next generation of intelligent connected edge devices while empowering an entire range of users. The company is eagerly waiting to work with industry leaders in unified 5G platforms and unleash the possibilities.

Although featuring a tiny form factor, NR-Light is mighty in performance. It features all the good aspects of 5G, starting from spectral efficiency and the ability to access new sub-6 GHz bands. High-end wearable devices, while incorporating the Snapdragon X35 modem, can communicate at the high speeds that 5G offers. In the industrial context, many IoT devices will be able to incorporate the X35 modem to improve their performance. The company is aiming its new modem at devices like Chromebooks, router products, low-end PCs, and many more. Another good feature is the new modem does not need an additional Qualcomm SoC to make it function.

To make it compatible with existing devices, Qualcomm has designed the Snapdragon X35 to support 4G LTE as well, as a fallback option. Even with such powerful features and working at such high speeds, the new modem consumes the lowest power of all the modems the company has manufactured so far. Although many other OEMs are showing a lot of interest, the first device to use this modem will emerge only in the first half of 2024. According to Qualcomm, the price of the Snapdragon X35 5G NR-Light modem will be around half that of its counterpart, the Snapdragon X55 modem.

Qualcomm has released more interesting features about their new modem. According to them, the Snapdragon X35 modem has the same interfaces as its predecessor LTE modems. This information is of vital importance for existing consumers with older designs. At least in theory, they can integrate the new modem in their designs with ease and avail the capabilities of 5G instantly.

Qualcomm has one more trick up its sleeve. They have announced another new modem, the Snapdragon X32, in addition to the Snapdragon X35 modem. They have designed the X32 modem as a modem-to-antenna solution suitable for use on lower-cost devices that work on NR-Light.

Future Diamond Transistors

At Northrop Grumman Mission Systems and Arizona State University, researchers are working on a new project, creating power transistors, but from diamond. They claim diamond power transistors are capable of very high efficiencies. This can significantly shrink the size of power transistors, leading to smaller electrical grid substations, and a potential drop in the cost of cell phone towers.

Manufacturers typically make power transistors from silicon. However, researchers are investigating diamond, because, they claim, it has very high thermal conductivity. Therefore, diamond conducts heat more than 8 to 10 times more efficiently than current materials like silicon. The researchers claim that at their full potential, transistors made of diamond can be smaller than regular power transistors by about 90 percent.

The breakdown field of diamonds is also high. That means, as compared to most other materials, a diamond can withstand large amounts of voltage, before failure. A high breakdown field is advantageous for applications involving high power. Therefore, diamond transistors will be vital to advancing the transition to renewable energy, while electrifying the transportation sector.

Although silicon has been the standard material for making most semiconductor devices, manufacturers also use gallium nitride and silicon carbide for the more advanced modern transistors, mainly for regulating the flow of electrical power. Now, researchers are studying the use of two new transistor materials—boron nitride and diamond,

The researchers are studying diamonds for the main body of the transistor, while they are interested in boron nitride as the electrical contact for the transistor. Similar to diamond, boron nitride, too, has high thermal conductivity and a high breakdown field,

The research team expects to make transistors by combining the two materials. According to them, the two materials complement each other, working even better than they do individually.

Their research will be useful for several applications, such as communication technologies. For instance, satellites typically operate on solar power, requiring transistors to turn power from solar panels into a form usable by the electronics. For launching satellites into space, one of the biggest impediments is its weight and size. Using a smaller power transistor can help to reduce both.

Smaller diamond transistors can improve many other communication technologies as well. This includes towers that cell phones need. Transistors handle the power that these tower systems need to produce radio frequencies for cell phone usage.

According to the researchers, cell phone designers and operators face a huge challenge of keeping the tower systems cool. This is especially true when the tower location is in hot environments, such as in Phoenix.

Cell phone towers typically use power transistors made of silicon, while the newer 5G towers use gallium nitride transistors. With their substantially better heat transfer characteristics, the new diamond transistors can drastically reduce the power needed to cool cell phone tower systems, and also make easier the task of keeping cell tower electronics from overheating.

In addition to communication technology, power conversion applications for electrical systems and the electrical grid will also benefit from the new power transistors made of boron nitride and diamond. Their higher efficiency will significantly reduce the size of electricity grid substations.

New MEMS Switches Accelerate Testing

If you are using processor ICs from Advanced Digital, testing them may be costly and logistically challenging. This is because testing these ICs requires isolated DC parametric test equipment, including high-speed digital ATE or automatic testing equipment to assuring the quality. New MEMS switch technology from ADI, working at 34 GHz, offers both DC and high-speed digital testing, despite having a small form factor in the form of a 5x4x0.9 mm LGA package. They reduce the test costs and simplify the logistics necessary for testing RF/digital SoCs or systems on chips.

There are many high-speed chips on the market. These include high-density inter-chip communications for advanced processors. Such advanced processors are the norm for 5G modems, computer graphics systems, and other central processing units. Therefore, ATE designers constantly face the increase in demand and complexity for throughput while assuring quality. For instance, the greatest challenge comes from the increasing number of transmitter/receiver channels, and these require both DC parametric and high-speed digital testing. Not only does this increase the testing time, but it also increases the complexity of the load board, while reducing the test throughput. In turn, this drives up operational expenses, while reducing the productivity of modern ATE environments.

One way of solving such ATE challenges requires a switch that not only operates at DC conditions but also at high frequencies. The new MEMS switch ADGM1001 from ADI, while passing true 0 Hz DC signals, can also operate equally effectively at high-speed signals up to 64 Gbps. Therefore, testing with these new switches requires only one insertion for an efficient single test platform. It is possible to configure the test platform for both DC parameter testing and standards for high-speed digital communications.

High-volume manufacturing requiring HSIO or high-speed input-output testing is often a challenge. Testing strategies typically employ a high-speed test architecture as a common approach for validating HSIO interfaces. Such test equipment typically incorporates two test paths in one configuration—one for DC tests, and the other for high-speed tests.

Testers employ a few methods for performing tests at both DC and high speed on HSIOs or digital SoCs. They may use relays, MEMS switches, or different load boards—one for DC testing, and the other for high-speed testing, but this requires two insertions.

Use of relays for DC and high-speed testing can be challenging. This is primarily due to relays being unable to operate beyond 8 GHz. Therefore, users must compromise on test coverage and signal speed. Moreover, relays take up large areas on PCBs on account of their larger size, and this makes the load boards rather large. Another concern with relays is their limited life and reliability. Relays typically only last for about 10 million cycles, thereby limiting the lifetime and system uptime of the load board.

With its superior density and small form factor, the 34 GHz MEMS switch from ADI offers both DC testing and high-speed digital testing capabilities, overcoming the above challenges.

Wearable Electronics with Screen-Printing

Although screen-printing methods are commonly useful for making T-shirts, manufacturers are now experimenting with the same technique for making flexible and wearable electronics. The easy manufacturing technique is also quite inexpensive.

The tech industry is increasingly promoting the popular use of flexible, wearable electronics. This promotion includes fitness trackers and smartwatches, which consumers are adopting widely. However, there is a huge challenge in making these devices—the process is rather error-prone, complex, and expensive.

Another challenge that manufacturers of such flexible, wearable electronics face are the high cost of raw materials. As the materials these devices require for the flexible sensors and displays are relatively new, they are expensive to produce in large quantities. Therefore, manufacturers find it difficult to produce high-quality and affordable devices.

The complexity of the manufacturing processes for these devices is another major challenge. The process of manufacturing these flexible, wearable electronic devices requires various steps, involving the printing of thin-film transistors, creating flexible substrates, and assembling the final device. Each step requires the execution to be at a high level of accuracy and precision. This not only increases the risk of errors but is also difficult to achieve.

In contrast, the screen-printing process, or the silk screen printing process, is a technique that is in use for centuries now. The process requires pushing ink through a mesh screen or stencil and depositing it on a surface. A non-permeable material blocks off sections of the mesh screen to leave open only the desired design. This allows ink to pass through only the openings.

Not only does the above process require very inexpensive and minimal material, but it is also incredibly simple as well, and anyone can do it by hand. So far, manufacturers of T-shirts have used this process, but now it has inspired a research team from Washington State University also. They experimented with the technique to check out its suitableness for printing flexible, wearable electrodes among other electronic components.

The team started by printing multiple layers of polyethylene glycol and polyimide mixture on a glass slide. They interspersed this printing with a conductive, patterned layer of silver. After completing the printing process, they peeled off the screen-printed material from the slide, affixing it to the body or fabric. Then they formed a serpentine, highly deformable pattern of electrodes, which could stretch to more than 30% of its regular size, and bend at up to 180 degrees without any damage.

The researchers created a wearable, real-time, wireless, electrocardiogram monitoring device using their new method, and put it to the test. They developed an algorithm to process the sensor data from the flexible printed circuit and the printed electrodes. Their device could accurately calculate respiratory rates, heart rate, and its variability metrics. According to the researchers, the variability metrics could have clinical applicability in the detection of arrhythmia.

The main advantage of the approach by the team is they can easily scale up their technique. Therefore, they can use the same technique for creating a single device or for mass-producing a commercial wearable. Moreover, the same technology is useful even beyond medical devices, such as in producing fitness trackers and smartwatches.

Nanowire Sensors

The Center of Excellence at the Australian Research Council for TMOS or Transformative Meta-Optical Systems, has announced the development of a new type of sensor. This is a minuscule sensor made for detecting nitrogen dioxide. They claim it can protect the environment from pollutants that vehicles typically release. These pollutants can cause acid rain and lung cancer.

According to the researchers, the sensor consists of an array of nanowires. The array occupies a square of only a fifth of a millimeter on each side. That means a silicon chip can easily incorporate the sensor.

The researchers have published their findings in the latest issue of Advanced Materials. They have described their sensor as not requiring any power source, as it has a built-in solar-powered generator to run it.

According to the researchers, by incorporating the new sensor into a network benefits the Internet of Things technology, as the sensor has low power consumption, low system size, and is inexpensive. They claim that it is possible to install the sensor into a vehicle. If the sensor were to detect dangerous levels of nitrogen dioxide from exhaust emissions, it will sound an alarm and send an alert to the owner’s phone.

The researchers feel this device is only a beginning, as they can adapt the sensor for the detection of other gases like acetone, which can lead to the design of a ketosis breath tester. Such a non-invasive tester can help to detect diabetic ketosis, saving countless lives.

This is an important development, as existing detectors require a trained operator and are bulky and slow. The new device, in contrast, detects gases instantly, measuring less than one part per billion of the gas. The prototype from TMOS even has a USB interface, allowing it to connect to a computer.

Belonging to the NOx category of pollutants, Nitrogen dioxide is highly dangerous to humans even when present in very small concentrations. Moreover, it contributes to acid rain, cars generate it commonly as a pollutant, and gas stoves can also generate it indoors.

Common to the fundamental construction of a solar cell, the nanowire sensor also consists of a PN junction, but in the shape of a nanowire. Sitting on a base, the nanowire is a small hexagonal pillar that has a diameter of about 100 nanometers. The complete sensor has a thousand of these nanowires in an ordered array, with the spacing between them measuring 600 nanometers.

Made from Indium Phosphide, the sensor has its base doped with zinc, forming the P part, while the tip of the nanowires forms the N section, as the researchers have doped it with silicon. Separating the P and N sections, the middle part of each of the nanowires remains undoped, constituting the intrinsic section.

As in the case of a solar cell, any light falling on the device causes the flow of a small current between the N and P sections. If nitrogen dioxide is present and touches the intrinsic middle section, there will be a dip in the current. This is due to nitrogen dioxide being a strong oxidizer that removes electrons.

Batteryless Microcontrollers for IoT

Ten years ago, IBM predicted the world will have one trillion connected devices by 2015. However, as 2015 rolled by, the world had yet to reach even 100 billion connected devices. The major problem—a trillion sensors mean at least a trillion batteries.

Although a significant problem, it did not make economic sense. Everyone was expecting the IoT technology to bring on a large value-addition, that of range. They expected IoT to bring the Internet to remote corners of the world, thereby interconnecting vast areas with IoT sensors and their information-gathering powers. Therefore, the internet and its incredible power would be visible in various places like large farms, factories, lumbering operations, construction sites, and mining operations, with enormous coverage and decentralized operations.

Typically, sensors collect data for IoT networks, which distribute it for processing and analysis. If sensors require batteries for operation, it places a severe restriction on the number of sensors that a network can use. This, in turn, goes on to defeat the entire point of having IoT in the first place.

For instance, consider a large-scale agricultural operation. IoT can bring major value addition to such a business through its coverage. By deploying multiple sensors across the entire operation, it is possible to access valuable information capable of generating highly actionable insights. Now consider the recurring cost of replacing or maintaining the huge number of batteries every year—making the proposition less compelling very quickly.

Not only would the resources, cost, and manpower, for replacing or maintaining the batteries on all the sensors be astronomical, but they would also easily surpass any possible savings that the system would likely bring.

According to an estimate, a trillion sensors would need 275 million battery replacements every day. This, assuming every battery deployed in the IoT network reached its claimed life of ten years. The next hurdle is even worse—discarded batteries poisoning the environment.

The above problem has resulted in sensors and microcontrollers getting more efficient and cheap. Modern sensors are now extremely reliable, consuming minuscule amounts of energy. Batteries have also improved, with the industry exhibiting robust batteries with higher energy density and longer life. However, the future of microcontrollers and IoT sensors needed to be batteryless. This led scientists and engineers to develop energy harvesting technologies that could eliminate the battery from IoT altogether. 

Energy harvesting is the technique of scavenging power from the surroundings, which has many forms of it—heat energy, electromagnetic energy, vibrational energy, and so on.

Considering that modern microcontrollers for IoT need only a few millivolts to operate, many are developing energy harvesting technologies as a potential power solution that can replace batteries.

This has given rise to self-powered microcontrollers in the market. For these MCUs, batteries impose no restrictions, as they harness their own energy from the environment. They use a number of harvesting technologies based on various power sources and kinds of materials—piezoelectricity, triboelectricity, and RF energy harvesting being the leading contenders in the category. Therefore, with energy harvesting powering microcontrollers, IoT can once again begin to chase the magic figure of one trillion interconnected devices.

Tiny Batteries Drive Microbots

Microbots are mobile robots, with characteristic dimensions below one micrometer. They are a part of the bigger family of common larger robots and a growing number of smaller nanorobots. In fact, the nature of microbots is common to both their larger and smaller cousins. Being autonomous, microbots use their onboard computers to move in insect-like maneuvers. Often, they are a part of a group of identical units that perform as a swarm does, under the control of a central computer.

With their insect-like form being a common feature, microbots are typically cheap to develop and manufacture. Scientists employ microbots for swarm robotics, using many of them and coordinating their behavior to perform a specific task. Combining many microbots compensates for their lack of individual computational capability, producing a behavior resembling that of an anthill or a beehive where insects cooperate to achieve a specific purpose.

With the field of microbotics still growing, microbots have a long way to develop further. Researchers are working with these devices, and they are investing their money, time, and effort in improving their capabilities.

With each new iteration, scientists are empowering microbots with more processing power, newer modes of locomotion, a larger number of sensors, and expanding their storage methods while providing them with newer techniques of energy harvesting. Recently, there has been a big breakthrough in tiny batteries that can help microbots drive further than ever before.

Generating a 9 VDC output, these tiny batteries are capable of driving motors directly. They stack multiple layers while turning components into packaging.

Several universities and a battery corporation have joined hands in creating the tiny batteries, a novel design that not only produces a high voltage but also boosts its storage capacity.

To unlock the full potential of microscale devices such as microbots, batteries must not only be tiny, they must also be powerful. According to the team that developed the tiny battery, its innovative design uses an improved architecture for its electrodes.

However, this was an unprecedented challenge. As the battery size reduces, the packaging begins to take up more of the available space, leaving precious little for the electrodes and the active ingredients that give the battery its performance.

Therefore, in place of working on the battery chemistry, the team started to work on a new packaging technology. They turned the negative and positive terminals of the battery into actual packaging, thereby saving considerable amounts of space.

By growing fully-dense non-polymer electrodes and combining them with vertical stacking, the team was able to make micro batteries that do not require carbon additives for electrodes. This allowed the micro batteries to easily outperform competitive models in capacity and voltage.

According to the team, limitations of power-dense micro- and nano-scale battery design were primarily due to cell design and electrode architecture. They have successfully created a microscale source of energy that has both volumetric energy density and high power density.

The higher voltage helps to reduce the electronic payload of a microbot. The 9 VDC from the tiny battery can power motors directly, bypassing energy losses associated with voltage boosting, allowing the small robots to either travel further or send more information to their human operators.

Batteries and Supercapacitors

In the past, only mission-critical devices had them. Now, a wide range of electronic applications demands backup power solutions. These applications include consumer, commercial, and industrial end-products. Of the several options available, the most energy-dense solution is that offered by supercapacitors, acting as energy reservoirs during interruptions of the main supply. Typically, this occurs during an outage of the mains power, or during swapping out batteries.

Although they are versatile, supercapacitors present challenges in design. This is due to their capacity to provide only 2.7 VDC. Potentially, this means adding multiple supercapacitors, along with the necessary cell-balancing circuitry, and voltage converters for step-up and step-down for supplying regulated power to the power rail operating at 5VDC. The solution is a nuanced and complex circuit, which not only takes up excessive board space but is also relatively expensive.

Comparing them with batteries can explain why supercapacitors offer many technical advantages for compact, low-voltage electronic applications. Supercapacitors help in designing simple, elegant solutions for powering a rail operating at 5VDC using only a single capacitor in combination with a buck/boost reversible voltage converter.

Modern electronic devices often need uninterruptible power as a critical element to provide a satisfactory user experience. The absence of a constant power source can not only stop the electronic product from operating, but it can also lead to vital information loss as well. For instance, a personal computer operating from mains power will lose the information contained in its volatile RAM during a power outage. Similarly, important blood glucose readings in the volatile memory of an insulin pump may be lost while replacing its batteries.

It is possible to prevent this from happening by including a backup battery. Not only will the battery store energy, but it can also release it during the failure of the main source of power. Currently, devices typically use lithium-ion batteries, as these are mature technology, offering very good energy density. This allows relatively compact devices to offer considerable backup power for relatively extended periods.

Irrespective of their base chemistries, batteries offer distinctive problematic characteristics under specific circumstances. Not only are they relatively heavy, but they also take relatively long times to recharge, which may be problematic in areas with frequent power outages. Moreover, it is possible to recharge the cells only a limited number of times, thereby increasing maintenance costs. In addition, batteries often include chemicals that can introduce environmental and safety hazards.

The supercapacitor, or ultracapacitor, offers an alternative solution. Technically, the supercapacitor is a capacitor with an electric double layer. Manufacturers construct supercapacitors using electrochemically stable, symmetric positive and negative carbon electrodes. They separate the electrodes by an ion-permeable separator that is insulating and use a container that they fill with an organic salt/solvent electrolyte.

Supercapacitor manufacturers design the electrolyte to maximize electrode wetting and iconic conductivity. The combination of the minuscule charge separation and high surface area of activated carbon electrodes results in the very high capacitance of the supercapacitor, as compared to the capacitance of regular capacitors.

The reliance on electrostatic mechanisms to store energy makes the electrical performance of supercapacitors more predictable than those of batteries.

Customer Project: Dual Power Supply

Our customer, Justin, purchased some parts for a dual power supply project and it works great! He said it can output up to +/-30v or 0-60v. It uses two 32vdc printer power supplies instead of a transformer which is inside the case.

See the pictures below of his completed project. Nice job, Justin!

Green and Wireless IoT

IoT or the Internet of Things presents devices with a collection of components for connecting various systems, software, and people via the Internet technology. Of these, the communications network is a crucial component, and the IoT wireless technology enables this. The communications network acts as the gateway between a software platform and an IoT device.

In many industries and even in daily life, the IoT is already displaying a major impact. IoT basically connects a variety of smart objects of different shapes and sizes, facilitating data exchange between them. These objects can be self-driven cars with sensors that can detect road obstacles, home-security systems, and temperature-controlled industrial equipment. Furthermore, the interconnection is often over the internet and other communications and sensing networks.

Several thin-film device technologies are emerging. They typically rely on alternative semiconductor materials, which can be nanocarbon allotropes, printable organics, and metal oxides. As suggested by an international team, KAUST, these could contribute to a more environmentally sustainable and economical Internet of Things.

By the next decade, expect the ballooning hyper-network of IoT to reach trillions of devices. This will boost the number of sensor devices this platform deploys.

The present IoT technology relies heavily on batteries to power sensor nodes. Unfortunately, batteries require regular replacement. That makes them environmentally harmful and expensive over time. Moreover, the present global production of lithium for battery materials may be unable to keep up with the increasing numbers of sensors and their energy demand.

An alternative approach relies on energy harvesters and wirelessly powered sensor nodes for achieving a more sustainable IoT. These energy harvesters may be radio-frequency-based, photovoltaic cell-based, or use other technologies. Such power sources could readily enable large-area electronics.

The KAUST team has assessed the viability of several large-area electronic technologies for their potential of delivering wirelessly powered IoT that is more eco-friendly.

Relative to conventional technologies based on silicon, large-area electronics are now emerging as an appealing alternative. This is because of the significant progress that solution-based processing is making, resulting in easily printable devices and circuits on flexible, large-area substrates. It is possible to produce them at low temperatures and on a variety of biodegradable substrates like paper. That allows more eco-friendly sensors in comparison to counterparts based on silicon.

The KAUST team has, over the years, been developing a wide range of radio-frequency-based electronic components. These include organic polymer and metal oxide-based semiconductor devices commonly known as Schottky diodes. For making wireless energy harvesters, these devices are very crucial, ultimately dictating the cost and performance of sensor nodes.

The KAUST team has been making key contributions that have included scalable methods of manufacturing RF diodes for harvesting energy. These diodes easily reach the 5G/6G frequency ranges. According to the team, these technologies are providing the necessary building blocks to sustain a trend towards a more sustainable way of powering the future billions of sensor nodes.

Currently, the team is investing in the integration of low-power monolithic devices with sensors and antennae for showcasing their true potential.