Yu-Chi Lin

EECS Department, University of California, Berkeley

Technical Report No. UCB/

December 1, 2025

This thesis presents the design and implementation of a voltage-controlled oscillator (VCO)-based ADC for neural signal acquisition, developed as part of wireless system-on-chip (SoC) target concurrent transcranial magnetic stimulation (TMS), magnetic resonance imaging (MRI), and electroencephalography (EEG) applications. This SoC is fabricated in Intel 16-nm FinFET process with 4 mm$^2$ footprint. The ADC employs a fully differential architecture, where each VCO consists of a voltage-to-current converter and a current-controlled ring oscillator. A median filter is implemented to mitigate clock-domain crossing between asynchronous oscillator and sampling clock. Additionally, a cascade integrator-comb (CIC) filter is employed for efficient decimation. The complete ADC is evaluated through end-to-end testing and verified with on-body electrocardiogram (ECG) recordings, demonstrating its potential for high-fidelity neural interfacing in multi-modal biomedical environments.

Advisors: Kristofer Pister and Ali Niknejad

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BibTeX citation:

@mastersthesis{Lin:31786,
    Author= {Lin, Yu-Chi},
    Editor= {Niknejad, Ali and Pister, Kristofer},
    Title= {Towards a TMS- and MRI- Compatible Wireless EEG System},
    School= {EECS Department, University of California, Berkeley},
    Year= {2025},
    Number= {UCB/},
    Abstract= {This thesis presents the design and implementation of a voltage-controlled oscillator (VCO)-based ADC for neural signal acquisition, developed as part of wireless system-on-chip (SoC) target concurrent transcranial magnetic stimulation (TMS), magnetic resonance imaging (MRI), and electroencephalography (EEG) applications. This SoC is fabricated in Intel 16-nm FinFET process with 4 mm$^2$ footprint. The ADC employs a fully differential architecture, where each VCO consists of a voltage-to-current converter and a current-controlled ring oscillator. A median filter is implemented to mitigate clock-domain crossing between asynchronous oscillator and sampling clock. Additionally, a cascade integrator-comb (CIC) filter is employed for efficient decimation. The complete ADC is evaluated through end-to-end testing and verified with on-body electrocardiogram (ECG) recordings, demonstrating its potential for high-fidelity neural interfacing in multi-modal biomedical environments.},
}

EndNote citation:

%0 Thesis
%A Lin, Yu-Chi 
%E Niknejad, Ali 
%E Pister, Kristofer 
%T Towards a TMS- and MRI- Compatible Wireless EEG System
%I EECS Department, University of California, Berkeley
%D 2025
%8 December 1
%@ UCB/
%F Lin:31786