Engineering Commons^™

Low-Noise Micro-Power Amplifiers For Biosignal Acquisition, Tan Yang

Doctoral Dissertations

There are many different types of biopotential signals, such as action potentials (APs), local field potentials (LFPs), electromyography (EMG), electrocardiogram (ECG), electroencephalogram (EEG), etc. Nerve action potentials play an important role for the analysis of human cognition, such as perception, memory, language, emotions, and motor control. EMGs provide vital information about the patients which allow clinicians to diagnose and treat many neuromuscular diseases, which could result in muscle paralysis, motor problems, etc. EEGs is critical in diagnosing epilepsy, sleep disorders, as well as brain tumors.

Biopotential signals are very weak, which requires the biopotential amplifier to exhibit low input-referred noise. …

The Design And Validation Of A Wireless Bat-Mounted Sonar Recording System, Jeremy Joseph Langford

Masters Theses

Scientists studying the behavior of bats monitor their echolocation calls, as their calls are important for navigation and feeding, but scientist are typically restricted to ground-based recording. Recording bat calls used for echolocation from the back of the bat as opposed to the ground offers the opportunity to study bat echolocation from a vantage otherwise only offered to the bats themselves. However, designing a bat mounted in-flight audio recording system, (bat-tag), capable of recording the ultra-sound used in bat echolocation presents a unique set of challenges. Chiefly, the bat-tag must be sufficiently light weight as to not overburden the bat, …

A Charge-Recycling Scheme And Ultra Low Voltage Self-Startup Charge Pump For Highly Energy Efficient Mixed Signal Systems-On-A-Chip, Chandradevi Ulaganathan

Doctoral Dissertations

The advent of battery operated sensor-based electronic systems has provided a pressing need to design energy-efficient, ultra-low power integrated circuits as a means to improve the battery lifetime. This dissertation describes a scheme to lower the power requirement of a digital circuit through the use of charge-recycling and dynamic supply-voltage scaling techniques. The novel charge-recycling scheme proposed in this research demonstrates the feasibility of operating digital circuits using the charge scavenged from the leakage and dynamic load currents inherent to digital design. The proposed scheme efficiently gathers the “ground-bound” charge into storage capacitor banks. This reclaimed charge is then subsequently …

Low-Voltage Bulk-Driven Amplifier Design And Its Application In Implantable Biomedical Sensors, Liang Zuo

Doctoral Dissertations

The powering unit usually represents a significant component of the implantable biomedical sensor system since the integrated circuits (ICs) inside for monitoring different physiological functions consume a great amount of power. One method to reduce the volume of the powering unit is to minimize the power supply voltage of the entire system. On the other hand, with the development of the deep sub-micron CMOS technologies, the minimum channel length for a single transistor has been scaled down aggressively which facilitates the reduction of the chip area as well. Unfortunately, as an inevitable part of analytic systems, analog circuits such as …