Electrical and Systems Engineering
Date of Award
Master of Arts (MA)
Chair and Committee
Robert Morley, Jr.
A third order delta-sigma modulator and associated low-pass digital filter is designed for an analog to digital converter: ADC) for sensing bioelectric phenomena. The third order noise shaping reduces the quantization noise in the baseband and the digital lowpass filter greatly attenuates the out of band quantization noise, increasing the effective number of bits. As part of a neural signal acquisition system designed by The BrainScope Company to capture Electro-Encephalogram: EEG) and Automated Brainstem Response: ABR) signals, this paper describes the design of a third order Delta-Sigma modulator which meets or exceeds the low noise specifications mandated by previous BrainScope products. The third order cascaded delta-sigma modulator attains a resolution of 12.3 bits in a signal bandwidth of 3kHz and 14.9 bits in a signal bandwidth of 100Hz, operating from a +/- 1.76V reference with a 250kHz clock.
Williams, Grant, "An Oversampled Analog To Digital Converter For Acquiring Neural Signals" (2009). All Theses and Dissertations (ETDs). 462.