When it comes to providing portable devices, the balance between performance and performance remains the main task of the design.
As the performance of mobile devices continues to improve, engineers continue to struggle to improve energy management.
The power / performance profile of laptops is not supported by the fact that they can only use small batteries. Larger batteries mean larger devices, and that’s not what the consumer wants, so there’s a strong interest in reducing the size of the battery, increasing battery efficiency and exploring ways to innovative ways to operate these devices.
Energy and performance issues are underlined by the increasing use of sensors and the fact that they must always be used to acquire, track, classify and store data.
According to Dr. Jacob Skinner, Managing Director of Thrive Wearables, could offer a solution to rapid improvements in silicon. This explains that processor designs work with lower and automatically tuned silicon voltages, provide more efficient process architectures, and optimize instruction sets.
“The processor development background is an ongoing effort to integrate the processing nodes directly with the wearable sensors, which minimizes data transfer (and power consumption) along the chain,” he says. he.
The Bosch BMA400 accelerometer series is a good example of this trend. This accelerometer requires less than 1 μA in full operation, but can handle sensor data independently. For example, it can convert the long triaxial motion stream into a number of steps.
To do this, the host (host microcontroller) is disabled for most of the time needed to track a user’s activity, and then z. B. every 100 steps woken up by the accelerometer itself. The sensor becomes the component that manages the full service cycle of the microcontroller, helping to reduce system performance while increasing efficiency.
Richard Edgar, chief technology officer at Imagination Technologies, believes that the device isolation feature is one possible way. He describes this approach as “energy islands”.
“Although you can capture data, you do not have to worry about it, and you do not need a high data rate for the data you want to transfer,” says Edgar. “By designing a system that only reacts in certain scenarios or perimeters, we can save electricity.
“Normally, the market wants you to provide improved specifications and even more sensitivity, but focusing on performance will be a barrier to saving energy.”
Richard Edgar, Director of the Imagination Technologies Technical Team
“What we need to evaluate is how much we can reduce the cell’s wake up time, the ability to miss important information, and process data accurately or in real time.”
Edgar suggests that power amplifiers are one of the biggest energy-consuming issues, with about 80 percent of today’s communications solutions spending most of their energy on just one.
He says this is “avoidable” and can be easily solved by replacing the existing power amplifiers with a low range of 0 dBm. “If you do that and the device only transmits a few hundred bytes a day, you should be able to extend the battery life to one year.”
Engineers are looking for smaller nodes to better manage their energy consumption and are also considering desensitizing their devices.
“Normally, the market wants you to provide improved specifications and greater sensitivity,” says Edgar, “but with a focus on performance, it will be a hindrance if you try to save energy.
“You need to know what’s the best compromise,” continues Edgar. “For example, if you need a laptop that transmits 100m or 1m, if it’s the last, you do not need a lot of power, so you can create a device with a lower specification. ”
The problem is whether consumers will be happy to accept less powerful devices in exchange for greater autonomy.
The cost of producing smaller and smaller nodes is also problematic, for example, according to Edgar, changing from 40 nm to 20 nm can result in a 30 to 40 percent increase in cost.
The exploration of alternative energy technologies raises interesting developments.
An alternative to traditional battery technology is the development of an expandable and rotating power supply, a bio-battery that can be integrated into a portable electronics.
According to Assistant Professor Seokheun Choi of Binghamton University, this technology can be printed directly onto a single textile substrate and establishes a standardized platform for flexible bio-batteries.
Assistant Professor Choi believes that textile-based notebooks are promising, but that the challenge is to create “a self-contained, stand-alone portable sensor system that does not rely on an external power source.”
“The microbial fuel cells (MFC) used in this work are probably the least developed for portable electronic applications because microbial cytotoxicity can cause health problems,” he says. “The work in portable MFCs has been quite limited, but since humans have more than 3.8 × 1013 bacterial cells versus 3.0 × 10 13 human cells in their bodies, the direct use of bacterial cells as a source energy is portable, conceivable electronics.
“Most microorganisms use respiration to convert the biochemical energy stored in organic matter into biological energy, adenosine triphosphate, in which a reaction cascade transfers electrons to the terminal electronic acceptor through a system of biomolecules carrying ‘electrons’, continues Professor Choi. “Most forms of respiration use a soluble compound as an electron acceptor, such as oxygen, but some microorganisms breathe solid electron acceptors to maintain biological energy.
“These microorganisms can transfer electrons generated by the metabolism to an external electrode via the cell membrane, MFCs generally comprise anodic and cathodic chambers separated by a proton exchange membrane, so that only H + or other cations can from the anode to the cathode the conductive charge connects the two electrodes to complete the external circuit. ”
Unlike conventional batteries and other enzymatic fuel cells, MFCs have complete microbial cells that can serve as a biocatalyst for stable enzyme reactions and longer lifetimes.
Assistant Professor Choi believes that organic fuels such as sewage, sweat and urine can be used as fuel to support bacterial viability, thus enabling the long-term use of MFCs.
Another potential source of energy is energy recovery, which Edgar believes could pave the way for more sustainable clothing, with movement being the most plausible way to generate power for portable devices. He is concerned about the cost of implementing energy recovery technology in silicon and why full use of energy recovery is not possible, but rather as a way to complementary to power devices.
Overall, Edgar believes that, at least in the short term, the solution to extend battery life is to “develop chips that consume less power and compromise the design by considering its commercial application.” .
“There are so many things we can do on the engineering side, they are based on other changes and techniques, like the development of new battery technologies,” he says. “This is denied because the most promising research seems to use rare materials and is inherently difficult to obtain.”
Energy sources and alternative techniques are emerging, but the question of whether they offer long-term solutions is another matter. For now, the answer is to judge if the performance can be lowered without greatly affecting the overall purpose of the device.
This compromise will be determined by consumer reactions, but they need to be better informed. When it comes to balancing performance and performance, it is not yet possible to consume and consume their technology.