Physical Sensors & Devices

Nutrients are essential parts of our lives for normal growth and development of body functions. An average person’s intake of nutrients per day is not enough to sustain body needs and thrive the development. To achieve optimal nutrient balance for development, especially in children, it is important to keep track of nutrients level in our body. Sweat, which contains many chemicals including vitamins and amino acids, is an attractive biofluid for routine non- invasive assessment of nutrients level. In this work, we developed a wearable sensor that can accurately provide...

To meet demands for mobile electronic, power has become limiting factor for most ADC design. In pipelined ADC structure, Inter-stage Gain circuits are the most power hungry building block. Conventionally, Inter-stage gain circuits are implemented using feedback an OTA with a less-than-1 feedback factor (i.e. 1/2 to 1/3). This approach is costly because these OTAs drive not only the load capacitors, but also the sampling and feedback capacitors. As a result, the power consumption of these amplifiers is a feedback factor (i.e., 2 to 3X) worse than their counterparts in unity gain...

High-performance gyroscopes are key elements of inertial navigation systems. Miniaturization of these sensors is desirable to achieve low manufacturing cost, low weight, small size, and low energy consumption. Although miniaturized gyroscopes have been used in a wide range of applications such as gaming and image stabilization, their low performance prevents their implementation in inertial navigation systems. The main goal of this research is to identify, analyze, and characterize parameters that limit the performance of frequency-modulated (FM) gyroscopes and develop extremely high-...

Ultrasonic transducers have been used in many applications from medical imaging to range finding. In recent years, applications have been further expanded to hand-held devices such as fingerprint sensors, and gesture recognitions thanks to advancements in micromachined ultrasonic transducers (MUTs). Compared to conventional ultrasound devices, MEMS ultrasonic transducers have advantages of higher resolution, higher bandwidth, and lower power consumption. More recently, products to interact electronic devices from a distance have been introduced. These products either require an allocated...