MIT chip harvests IoT potential
23 Jun 2015
An ultralow-power circuit developed by engineers at the Massachusetts Institute of Technology (MIT) improves efficiency of energy harvesting to over 80%.
The engineers, who presented their power converter chip at the Symposia on VLSI Technology and Circuits last week, said the device could be used help implement the Internet of Things (IoT).
The IoT suggests that any ’thing’ that can be assigned an IP address - such as a car, a manufacturing device, or even an animal - can be inexplicably integrated into vast information networks to help report on anything from condition monitoring, to maintenance requirements and can be harnessed to improve productivity.
“We need to regulate the input to extract the maximum power
MIT graduate Dina Reda El-Damak
To make the IoT a reality, the MIT researchers said ultralow-power sensors that can run for months without battery changes, or, that can extract energy from the environment to recharge, are hugely important.
Previous experimental ultralow-power converters had efficiencies of around 40-50%, whereas the MIT device can harvest more than 80% of the energy filtering into it, even at the extremely low power levels characteristic of tiny solar cells, the researchers claimed.
What’s more, the MIT research team said its device can achieve those efficiency improvements while assuming additional responsibilities.
Where its predecessors could use a solar cell to either charge a battery or directly power a device, the MIT chip can do both, and it can power the device directly from the battery, the researchers said.
“We still want to have battery-charging capability, and we still want to provide a regulated output voltage,” said Dina Reda El-Damak, an MIT graduate student in electrical engineering and computer science and first author on the new paper.
All of the chip’s operations share a single inductor that saves on circuit board space but increases the circuit complexity even further, the researchers said.
“We need to regulate the input to extract the maximum power, and we really want to do all these tasks with inductor sharing and see which operational mode is the best,” El-Damak said.
“And we want to do it without compromising the performance, at very limited input power levels – 10 nanowatts to 1 microwatt – for the Internet of Things.”
A step forward?
The power circuit described by El-Damak could be the breakthrough many in the science, technology, engineering and maths (STEM) community have been waiting for.
While at the chemical industries trade show Achema in Germany last week, many of the 3,000 exhibitors - including the likes of Siemens and ABB - stressed the importance of effectively implementing the IoT and ’Industry 4.0’ - a German term that represents the widespread uptake of advanced technologies such as cyber-physical systems and powerful analytical tools as a means of streamlining manufacturing and production processes - much like the IoT.
With every connected sensor, piece of equipment or integrated device, energy will be a massive issue, as the MIT researchers have outlined.
And although the widespread uptake of the IoT, and indeed Industry 4.0, looks to be some way off yet (if several of the conversations I had while at Achema are to be believed), getting the most basic requirements right - such as effective energy consumption/ generation - seems to be a step in the right direction.