IoT design space challenges: Circuits and systems

Abstract

The Internet of Things (IoT) is a rapidly emerging application space, poised to become the largest electronics market for the semiconductor industry. IoT devices are focused on sensing and actuating of our physical environment and have a nearly unlimited breadth of uses. In this paper, we explore the IoT application space and then identify two common challenges that exist across this space: ultra-low power operation and system design using modular, composable components. We survey recent low power techniques and discuss a low power bus that enables modular design. Finally, we conclude with three example ultra-low power, millimeter-scale IoT systems. IoT Application Space and ChallengesIoT devices are unique in that they are focused on physical interfaces, allowing them to sense and actuate the world around us. This is in contrast to previous computing platforms, such as desktop and handheld devices, which have primarily focused on human interfaces. These human interfaces require relatively large input and output devices and require the devices to be co-located with their users. In contrast, IoT devices receive input through sensors that are often highly miniaturized through MEMS technology and send out information through wired or wireless interfaces to mobile and cloud computers. This enables the placement of IoT devices in myrad new locations and applications where computing was previously absent. As a result, IoT presents the semiconductor industry with a market opportunity that may exceed that of all previous computing classes.The diversity of our physical environment results in a similarly diverse IoT application space that ranges from tiny implanted heart-rhythm monitors, to large, extremely long lifetime HVAC sensors, to sensors for oil reservoir diagnosis [1]. To categorize this wide application space we recognize four ontological properties that are critical in determining IoT device requirements: sensing modality, form factor (size), energy source / sensor lifetime, and connectivity. Table 1 lists example values for these properties. For instance, physical form factor can range from tiny millimeter size for implantable sensors to 10s of centimeters for infrastructure monitoring. Sensing modalities can include pressure, chemical, strain, and temperature, etc. In addition, the sensing modality can be characterized by measurement frequency and possible triggers , such as a timer, a detected event in the monitored value, or an external event such as a radio message.Similarly, communication connectivity is characterized by communication interval, distance, data rate/size, etc. Clearly the listed items are not exhaustive. Each property can take a very large number of possible values resulting in a highly varied application space. Some examples include 1) tiny sensors that measure temperature every 10 minutes using a secondary battery and harvesting with infrequent communication for studying Pika's in the Rocky mountains [2]; 2) continuous monitoring of brain activity in seizure patients with a contin...

A Compact Adder and Reprogrammable Logic Gate Using Micro-Electromechanical Resonators With Partial Electrodes

“…Note that in Table 1, design 3, 4, and 5 show that for the same resonator dimensions, by lowering the quality factor, which can be partially controlled by the vacuum level during testing, the speed increases. However, the minimum required separation between the different resonance peaks increases according to (1) and higher voltages will be required to ensure that, which results in higher energy per operation.…”

“…HE continuous miniaturization of the complementarymetal-oxide-semiconductor (CMOS) technology has led to higher operational speeds, while the leakage energy and power density have increased. However, IoT devices and sensors do not require high performance and only require moderate data transmission and computation speeds, in the range of sub-kHz to 100 MHz [1][2]. The most critical aspect in such applications is the energy-efficiency of battery-operated, often stand-alone sensors and gadgets.…”

Constraints in the IoT: The World in 2020 and Beyond

“…Such high modular approach will combine existing chips within size and power constraint. In [25], some theoretical low power circuit solution is proposed. Nevertheless, this area needs a lot of research and effort without which the IoT cannot be achieved.…”

High Speed, Low Area Exact Speculative Carry Look Ahead Adder using MGDI Technique

“…The adders optimized in terms of speed by means of using the appropriate methods to reduce the delay of the circuit which is suitable for this work too. Using appropriate technique, it is possible to reduce the delay and optimize the design area with possible low power requirements within the allowable degradation limit [7]. With the help of speculative method, the accuracy can be traded off to achieve circuit speed and power.…”