{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/86627"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/86627","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"VCO ADC in Electrical Impedance Tomography Measurements and Physical Unclonable Function for Hardware Security Application","abstract":"Ph.D.","abstract_html":"Ph.D.","abstract_has_math":false,"creators":["Danesh, Mohammadhadi; 0000-0001-8395-0025"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Sanyal, Arindam","Electrical Engineering"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-02-21T21:35:47Z","date_published":"2025-02-21T21:35:47Z","updated_at":"2026-07-27T19:05:32Z","subjects":["electrical engineering"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/86627","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Sanyal, Arindam","Electrical Engineering"]},{"key":"dc:creator","label":"Author","values":["Danesh, Mohammadhadi; 0000-0001-8395-0025"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2025-02-21T21:35:47Z","2020"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["electrical engineering"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/86627"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Ph.D.","In this thesis, novel techniques and methods of designing and implementing ring voltage-controlled oscillator (VCO) analog-to-digital converters (ADC)s for the application of electrical impedance tomography (EIT) measurements are presented. All the EIT systems, reported so far and have been implemented by successive approximation register (SAR) ADC, have two main issues of 1) consuming tens of mW power due to such power hungry elements as instrumentation amplifier, ADC driver and SAR logic and 2) kick-back noise. In this thesis, we showed that traditionally use of SAR ADCs in EIT systems can be abolished and replaced by VCO ADCs since our taped-out VCO ADC has reached to stunning and excellent results. The measurement results show that the designated readout circuit, in which ADC playes the most significant role, consumes only 90µW power dissipation bringing about the figure-of-merit (FoM)of 0.13pW/Hz which is 9x better than other state-of-the-art works using SAR ADC. Also, using the VCO-based ADC in EIT system, the measured amplitude and phase error of the phantom impedance have been obtained by only 2.8% and 0.86 degrees which are very competitive to other readout circuits. However, this is not the end of story. Since we have verified the superiority of VCO-based ADCs in EIT systems, the main focus has gone for new design techniques and improving VCO ADC performance. In this regard, we took the advantage of multi-stage noise shaping (MASH) architecture to eliminate the excessive loop delay (ELD) issues of closed-loop architecture which was used in the EIT measurement. We have presented two 1-1 and 1-2 MASH VCO ADC in which the first stages has applied an open-loop VCO ADC to get ride of ELD. In the 1-1 MASH ADC, the second stage designed to be similar to the first stage so that brings about a second-order noise shaping VCO ADC while the 1-2 MASH ADC has a second-order VCO ADC in the second stage to provide ultimately a third-order noise shaping ADC. In VCO-based modulators, mismatch of VCOs are unavoidable and affects the modulators performance. In this regard, we took the advantage of using the VCOs' mismatch to create a physical unclonable function (PUF) response as a hardware secret key. We taped-out this PUF based on the mismatch of VCOs and current steering digital-to-analog converters (DAC)s. Basically, use of VCO as a phase-domain integrator allows amplification of small mismatches with time and and is used to creat an N-bit PUF key from a single PUF cell by quantizing the VCO phase for N cycles. This PUF is highly digital and its energy consumption is expected to improve with technology scaling. The PUF circuit has been taped-out in 65nm technology process with the supply voltage of 1.2V. The PUF chip achieved power consumption of 36µW and the energy/bit of 85 for the 2048-bit PUF response that is more than 12x better than other state-of-the-art works. Intra and Inter-hamming distance (HD) have been measured for the supply and temperature range of 0.9V-1.2V and 0-50C for 4 PUFs and 16 PUFs, respectively. The measured Inter-HD and Intra-HD of 0.4859 and 0.0906 shows the robust reliability of PUF response.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["VCO ADC in Electrical Impedance Tomography Measurements and Physical Unclonable Function for Hardware Security Application"]}]}],"canonical_facts":{"dc:contributor":["Sanyal, Arindam","Electrical Engineering"],"dc:creator":["Danesh, Mohammadhadi; 0000-0001-8395-0025"],"dc:date":["2025-02-21T21:35:47Z","2020"],"dc:description":["Ph.D.","In this thesis, novel techniques and methods of designing and implementing ring voltage-controlled oscillator (VCO) analog-to-digital converters (ADC)s for the application of electrical impedance tomography (EIT) measurements are presented. All the EIT systems, reported so far and have been implemented by successive approximation register (SAR) ADC, have two main issues of 1) consuming tens of mW power due to such power hungry elements as instrumentation amplifier, ADC driver and SAR logic and 2) kick-back noise. In this thesis, we showed that traditionally use of SAR ADCs in EIT systems can be abolished and replaced by VCO ADCs since our taped-out VCO ADC has reached to stunning and excellent results. The measurement results show that the designated readout circuit, in which ADC playes the most significant role, consumes only 90µW power dissipation bringing about the figure-of-merit (FoM)of 0.13pW/Hz which is 9x better than other state-of-the-art works using SAR ADC. Also, using the VCO-based ADC in EIT system, the measured amplitude and phase error of the phantom impedance have been obtained by only 2.8% and 0.86 degrees which are very competitive to other readout circuits. However, this is not the end of story. Since we have verified the superiority of VCO-based ADCs in EIT systems, the main focus has gone for new design techniques and improving VCO ADC performance. In this regard, we took the advantage of multi-stage noise shaping (MASH) architecture to eliminate the excessive loop delay (ELD) issues of closed-loop architecture which was used in the EIT measurement. We have presented two 1-1 and 1-2 MASH VCO ADC in which the first stages has applied an open-loop VCO ADC to get ride of ELD. In the 1-1 MASH ADC, the second stage designed to be similar to the first stage so that brings about a second-order noise shaping VCO ADC while the 1-2 MASH ADC has a second-order VCO ADC in the second stage to provide ultimately a third-order noise shaping ADC. In VCO-based modulators, mismatch of VCOs are unavoidable and affects the modulators performance. In this regard, we took the advantage of using the VCOs' mismatch to create a physical unclonable function (PUF) response as a hardware secret key. We taped-out this PUF based on the mismatch of VCOs and current steering digital-to-analog converters (DAC)s. Basically, use of VCO as a phase-domain integrator allows amplification of small mismatches with time and and is used to creat an N-bit PUF key from a single PUF cell by quantizing the VCO phase for N cycles. This PUF is highly digital and its energy consumption is expected to improve with technology scaling. The PUF circuit has been taped-out in 65nm technology process with the supply voltage of 1.2V. The PUF chip achieved power consumption of 36µW and the energy/bit of 85 for the 2048-bit PUF response that is more than 12x better than other state-of-the-art works. Intra and Inter-hamming distance (HD) have been measured for the supply and temperature range of 0.9V-1.2V and 0-50C for 4 PUFs and 16 PUFs, respectively. The measured Inter-HD and Intra-HD of 0.4859 and 0.0906 shows the robust reliability of PUF response.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/86627"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["electrical engineering"],"dc:title":["VCO ADC in Electrical Impedance Tomography Measurements and Physical Unclonable Function for Hardware Security Application"],"dc:type":["Text","Dissertation"]},"updated_at":"2026-07-27T19:05:32Z"}