Reinforcement bipolar read: addressing read disturb in RRAM

Memory advances have not kept up with computing demands. Emerging device technology Resistive RAM (RRAM) addresses this by enabling computation-in-memory. However, RRAM suffers from read disturb, limiting viability. While earlier work has had some success in reducing read disturb by switching the read current direction (a bipolar read scheme),...

Artifact-Free Neurostimulator with Arbitrary Waveform Generation for High-Channel, High-Density Bidirectional Neural Interfaces

To achieve greater specificity in neurostimulation, bidirectional neural interfaces are required to verify the recorded neural response after stimulation. The specific neural interface targeted in this thesis is the epiretinal implant. Due to the heterogeneity of the retinal ganglion cells (RGCs), high-fidelity vision is only possible when all...

An Optimised Approach to Wireless Power Transfer for an Artificial Retina Implant

An artificial retina can replace some of the functionality of the eye in people that have experienced partial or complete loss of vision. Loss of vision is associated with many negative effects in one’s life and can be a debilitating condition. Artificial retinas in the form of a chip thus offer the potential to greatly improve people’s lives....

A Novel Neural Recording IC with Adaptive Gain Control for Wide-Dynamic Range Closed-Loop Neural Interfaces

Bidirectional neural recording ICs faces the challenge of simultaneous stimulation and recording. The recording IC should endure large stimulation artifacts while capturing weak neural signals excited by the stimuli. The stimulation artifacts can be as large as hundreds of millivolts, which can saturate the recording front end. Conventional...

Optimizing Sensitivity of Capacitive Pressure Sensors for Improved Intraocular Pressure Monitoring: Exploring the Impact of Spiral Shaped Antenna Geometries on Q-Factor and Resonance Frequency Output

This thesis analyzes and describes a wearable pressure sensor to detect intraocular pressure and guide clinician diagnosis of glaucoma. Although glaucoma has many<br/>symptoms and risk factors, high intraocular pressure is the most predominant. A method to continuously and accurately record intraocular pressure measurements and fluctuations in a...

Assessment Of The Spike Detection Performance Of The Wired-OR Readout Architecture

Abstract—This paper investigates the performance of commonly used spike detection algorithms (Absolute Amplitude Thresholding and Non-linear Energy Operator) on compressed neural signals using a novel wired-OR lossy compression algorithm. Performing compression with the wired-OR architecture mainly removes the noisy baseline and preserves spikes...

An 11-bit 2MS/s column parallel SAR-RAMP ADC for ToF imager readout

Time-of-Flight (ToF) is an optical range detection technique that derives range from the round-trip time of light pulse between the imager and the target. Due to the simple hardware and distance extraction algorithm, ToF imagers are widely adopted in existing (automotive, consumer electronics, etc.) and emerging (AR/VR, etc.) applications...

Design of Flexible Dry CNT/PDMS Electrodes for In-ear EEG: The Effect of Microstructures on Electrode Performance

In-ear EEG is a discreet and convenient method for monitoring EEG by placing the electrodes in the ear canal. This enables everyday monitoring outside of clinical environments in contrast to generally used scalp EEG with wet electrodes. This thesis proposes and describes the design of novel flexible dry CNT/PDMS electrodes with short pins, long...

Always-on wireless ear-EEG to monitor brain activity: Electronics design

Currently, EEG recordings are mostly made using scalp recording devices. These devices are typically difficult to put on and bulky, limiting their use to a lab environment. In-ear EEG recording is proposed as a more practical alternative to scalp EEG recording. <br/><br/>In-ear EEG replaces the scalp electrode array with more discrete earpieces,...

Compact Neural Amplifier for Next-Generation Brain-Machine Interfaces

Brain-machine interfaces (BMI) are electronic devices that form an interconnection between the users brain and an external device through which the user can control the device and the device can apply stimulation to the users brain or nervous system. BMIs have undergone a rapid evolution in development and applications. While the first...

3 Factor Authentication Using a Dry-Electrode In-Ear Electroencephalography recorder: A research on the feasibility of several classification methods

This bachelor end project thesis is describing ways to use dry-electrode electroencephalography (EEG) measurements for authentication. There are five proposed methods based on the literature study, which in this report are called: ’frequency tagging’, ’pseudowords’, ’familiar music’, ’mental tasks’, and ’emotions’. First, all methods were tested...

Epileptic seizure detection using near-ear EEG

60 million people around the world have epilepsy, which is a neurological disorder that severely impacts their day to day life negatively. Currently available methods to reduce the effects of epilepsy are either ineffective or require expensive and invasive surgery. A new method has been found that can suppress epilepsy without the need of...

Agar/NaCl tissue phantom mimicking electrical properties of human body in low frequency spectrum: A Brain-Computer Interface Inside Your Earphones

This report details the design and development of an agar/NaCl gel-like tissue phantom mimicking the electrical properties of wet human skin. The skin phantom provides a reliable, reproducible testing ground for dry-contact polydimethylsiloxane (CNT/PDMS) electrodes, with the aim of recording electroencephalograms (EEGs) and stimulating brain...

Transcutaneous Vagus Nerve Stimulation Through an In-Ear Device For Epilepsy Treatment

Several studies have illustrated that Transcutaneous Vagus Nerve Stimulation (t-VNS) is an effective method for epileptic treatment. In contrast to the classical invasive Vagus Nerve Stimulation (VNS) which is already a Food and Drug Administration (FDA) approved therapy for epileptic treatment, t-VNS does not require surgical intervention....

Artifact-Free Stimulation for Next-Generation Single-Cell Resolution Epiretinal Implants

Implantable epiretinal prostheses aim to restore visual capability for patients suffering from diseases such as Macular Degeneration and Retinitis Pigmentosa by bypassing damaged photoreceptors and electrically exciting Retinal Ganglion Cells (RGCs) directly. Next-generation devices will require single-cell resolution, and bidirectional...