14 research outputs found
BÄ°yopotansiyel iĆaretlerin ikinci nesil akım taĆıyıcılar ile iĆlenmesi ve yeni bir EKG devresi tasarımı
06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan âYĂŒkseköÄretim Kanunu Ä°le Bazı Kanun Ve Kanun HĂŒkmĂŒnde Kararnamelerde DeÄiĆiklik Yapılması Hakkında Kanunâ ile 18.06.2018 tarihli âLisansĂŒstĂŒ Tezlerin Elektronik Ortamda Toplanması, DĂŒzenlenmesi ve EriĆime Açılmasına Ä°liĆkin Yönergeâ gereÄince tam metin eriĆime açılmıĆtır.Anahtar kelimeler: CCII, ikinci nesil akım taĆıyıcılar, filtre, EKG Bu çalıĆmada bir EKG cihazı tasarlanmÄ±Ć ve bu cihaz ikinci nesil akım taĆıyıcılar ile gerçekleĆtirilmiĆtir. Bu EKG devresinde ikinci nesil akım taĆıyıcılar filtre olarak kullanılmıĆtır. Bu cihazın doÄruluÄunu kontrol edebilmek ve karĆılaĆtırmasını yapabilmek için Sakarya Ăniversitesi Elektrik-Elektronik MĂŒhendisliÄi'ne ait olan BIOPAC Systems Inc. Ćirketinin imal ettiÄi MP36 EKG cihazı ile ölĂ§ĂŒmler eĆ zamanlı olarak yapılmıĆtır. Ayrıca OPAMP'larla tasarlanan bir EKG devresi de gerçekleĆtirilmiĆ ve sonuçları deÄerlendirilmiĆtir. OPAMP'larla gerçekleĆtirilen bu devre ikinci nesil akım taĆıyıcılarla yeniden dizayn edilmiĆ ve gerçekleĆtirilerek sonuçları deÄerlendirilmiĆtir. Böylece OPAMP'larla gerçekleĆtirilmiĆ bir EKG devresi, ikinci nesil akım taĆıyıcılarla yeniden dizayn edilmiĆ bir EKG devresi, bu çalıĆmada tasarlanmÄ±Ć ve ikinci nesil akım taĆıyıcılarla tasarlanmÄ±Ć bir EKG devresi, MP36 devresi ve daha önce literatĂŒrde gerçekleĆtirilmiĆ EKG devrelerinin kıyaslaması yapılmıĆtır. Ayrıca biyomedikal cihazlarda sıklıkla kullanılan filtreler, yĂŒkselteçler ve bazı devreler simule edilmiĆtir. CCII tabanlı olan devrede gĂŒrĂŒltĂŒler minimuma inmiĆ ve çok net EKG ölĂ§ĂŒmĂŒ yapılabilmiĆtir. EKG devresi 9,5*9,5 cm2 boyutlarına kadar indirgenebilmiĆtir. Entegrelerin ve diÄer elemanların SMD tĂŒrlerinin kullanılması ile daha da kĂŒĂ§ĂŒltĂŒlebilmesi mĂŒmkĂŒndĂŒr. Gerçeklenen devre maliyet açısından da avantajlıdır. 4 adet kalem pille çalıĆabilir olması da bir diÄer avantajıdır. CMRR oranı, frekans aralıÄı, yĂŒkseltme oranı ve uygulanabilme kolaylıÄı açısından CCII tabanlı olan EKG devrelerinin daha avantajlı olduÄu sonucu ortaya çıkmaktadır. Ayrıca bu çalıĆmada rezonans frekansını ayarlamak ve daha iyi sonuç elde edebilmek için CCII yapısına ayarlı dirençler eklenmesi sebebiyle 5 Hz ile 100 MHz arasında bir kesim frekansına sahip bir filtre yapısı öne sĂŒrĂŒldĂŒ ve bu devrede kullanılabilir olduÄu gözlemlendi.Keywords: CCII, second generation current conveyors, filter, ECG In this study, an ECG device was designed and this device was carried out with second generation current carriers. Second generation current carriers were used as filters in this ECG circuit. Measurements were simultaneously performed with MP36 ECG device produced by BIOPAC Systems Inc. that is belong to Sakarya University Electrical and Electronics Engineering Department in order to be able to check and compare accuracy of this device. An ECG circuit designed with OPAMPs was also carried out and results were evaluated. This circuit, which was realized with OPAMPs, was redesigned with second generation current carriers and results were evaluated by performing. Thus, an ECG circuit realized with OPAMPs, a redesigned ECG circuit with second generation current carriers were designed in this study, and an ECG circuit with second generation current carriers, MP36 circuit and previous circuits in literature were compared. In addition, filters, amplifiers and some circuits, which are frequently used in biomedical devices are simulated. Noises were reduced to minimum in CCII-based circuit and very clear ECG measurements was done. ECG circuit can be reduced to size of 9.5 * 9.5 cm2. It is possible to further reduce integrals and other elements by use of SMD types. Performed circuit is also advantageous in terms of cost. Another advantage is that it can work with 4 batteries. It was concluded that CCII based ECG circuits are more advantageous in terms of CMRR ratio, frequency range, amplification rate and ease of application. Also, in this study, a filter structure having a cut-off frequency between 5 Hz to 100 MHz was proposed because of adding adjusted resistors to CCII structure to adjust resonance frequency and achieve better results, and it was observed to be usable in this circuit
Low Voltage Low Power Analogue Circuits Design
DisertaÄnĂ prĂĄce je zamÄĆena na vĂœzkum nejbÄĆŸnÄjĆĄĂch metod, kterĂ© se vyuĆŸĂvajĂ pĆi nĂĄvrhu analogovĂœch obvodĆŻ s vyuĆŸitĂ nĂzkonapÄĆ„ovĂœch (LV) a nĂzkopĆĂkonovĂœch (LP) struktur. Tyto LV LP obvody mohou bĂœt vytvoĆeny dĂky vyspÄlĂœm technologiĂm nebo takĂ© vyuĆŸitĂm pokroÄilĂœch technik nĂĄvrhu. DisertaÄnĂ prĂĄce se zabĂœvĂĄ prĂĄvÄ pokroÄilĂœmi technikami nĂĄvrhu, pĆedevĆĄĂm pak nekonvenÄnĂmi. Mezi tyto techniky patĆĂ vyuĆŸitĂ prvkĆŻ s ĆĂzenĂœm substrĂĄtem (bulk-driven - BD), s plovoucĂm hradlem (floating-gate - FG), s kvazi plovoucĂm hradlem (quasi-floating-gate - QFG), s ĆĂzenĂœm substrĂĄtem s plovoucĂm hradlem (bulk-driven floating-gate - BD-FG) a s ĆĂzenĂœm substrĂĄtem s kvazi plovoucĂm hradlem (quasi-floating-gate - BD-QFG). PrĂĄce je takĂ© orientovĂĄna na moĆŸnĂ© zpĆŻsoby implementace znĂĄmĂœch a modernĂch aktivnĂch prvkĆŻ pracujĂcĂch v napÄĆ„ovĂ©m, proudovĂ©m nebo mix-mĂłdu. Mezi tyto prvky lze zaÄlenit zesilovaÄe typu OTA (operational transconductance amplifier), CCII (second generation current conveyor), FB-CCII (fully-differential second generation current conveyor), FB-DDA (fully-balanced differential difference amplifier), VDTA (voltage differencing transconductance amplifier), CC-CDBA (current-controlled current differencing buffered amplifier) a CFOA (current feedback operational amplifier). Za ĂșÄelem potvrzenĂ funkÄnosti a chovĂĄnĂ vĂœĆĄe zmĂnÄnĂœch struktur a prvkĆŻ byly vytvoĆeny pĆĂklady aplikacĂ, kterĂ© simulujĂ usmÄrĆovacĂ a induktanÄnĂ vlastnosti diody, dĂĄle pak filtry dolnĂ propusti, pĂĄsmovĂ© propusti a takĂ© univerzĂĄlnĂ filtry. VĆĄechny aktivnĂ prvky a pĆĂklady aplikacĂ byly ovÄĆeny pomocĂ PSpice simulacĂ s vyuĆŸitĂm parametrĆŻ technologie 0,18 m TSMC CMOS. Pro ilustraci pĆesnĂ©ho a ĂșÄinnĂ©ho chovĂĄnĂ struktur je v disertaÄnĂ prĂĄci zahrnuto velkĂ© mnoĆŸstvĂ simulaÄnĂch vĂœsledkĆŻ.The dissertation thesis is aiming at examining the most common methods adopted by analog circuits' designers in order to achieve low voltage (LV) low power (LP) configurations. The capability of LV LP operation could be achieved either by developed technologies or by design techniques. The thesis is concentrating upon design techniques, especially the nonâconventional ones which are bulkâdriven (BD), floatingâgate (FG), quasiâfloatingâgate (QFG), bulkâdriven floatingâgate (BDâFG) and bulkâdriven quasiâfloatingâgate (BDâQFG) techniques. The thesis also looks at ways of implementing structures of wellâknown and modern active elements operating in voltageâ, currentâ, and mixedâmode such as operational transconductance amplifier (OTA), second generation current conveyor (CCII), fullyâdifferential second generation current conveyor (FBâCCII), fullyâbalanced differential difference amplifier (FBâDDA), voltage differencing transconductance amplifier (VDTA), currentâcontrolled current differencing buffered amplifier (CCâCDBA) and current feedback operational amplifier (CFOA). In order to confirm the functionality and behavior of these configurations and elements, they have been utilized in application examples such as diodeâless rectifier and inductance simulations, as well as lowâpass, bandâpass and universal filters. All active elements and application examples have been verified by PSpice simulator using the 0.18 m TSMC CMOS parameters. Sufficient numbers of simulated plots are included in this thesis to illustrate the precise and strong behavior of structures.
Utilizing Unconventional CMOS Techniques for Low Voltage Low Power Analog Circuits Design for Biomedical Applications
Tato disertaÄnĂ prĂĄce se zabĂœvĂĄ navrĆŸenĂm nĂzkonapÄĆ„ovĂœch, nĂzkopĆĂkonovĂœch analogovĂœch obvodĆŻ, kterĂ© pouĆŸĂvajĂ nekonvenÄnĂ techniky CMOS. LĂ©kaĆskĂĄ zaĆĂzenĂ na bateriovĂ© napĂĄjenĂ, jako systĂ©my pro dlouhodobĂœ fyziologickĂœ monitoring, pĆenosnĂ© systĂ©my, implantovatelnĂ© systĂ©my a systĂ©my vhodnĂ© na noĆĄenĂ, musĂ bĂœt male a lehkĂ©. KromÄ toho je nutnĂ©, aby byly tyto systĂ©my vybaveny bateriĂ s dlouhou ĆŸivotnostĂ. Z tohoto dĆŻvodu pĆevlĂĄdajĂ v biomedicĂnskĂœch aplikacĂch tohoto typu nĂzkopĆĂkonovĂ© integrovanĂ© obvody. NekonvenÄnĂ techniky jako napĆ. vyuĆŸitĂ transistorĆŻ s ĆĂzenĂœm substrĂĄtem (Bulk-Driven âBDâ), s plovoucĂm hradlem (Floating-Gate âFGâ), s kvazi plovoucĂm hradlem (Quasi-Floating-Gate âQFGâ), s ĆĂzenĂœm substrĂĄtem s plovoucĂm hradlem (Bulk-Driven Floating-Gate âBD-FGâ) a s ĆĂzenĂœm substrĂĄtem s kvazi plovoucĂm hradlem (Bulk-Driven Quasi-Floating-Gate âBD-QFGâ), se v nedĂĄvnĂ© dobÄ ukĂĄzaly jako efektivnĂ prostĆedek ke zjednoduĆĄenĂ obvodovĂ©ho zapojenĂ a ke snĂĆŸenĂ velikosti napĂĄjecĂho napÄtĂ smÄrem k prahovĂ©mu napÄtĂ u tranzistorĆŻ MOS (MOST). V prĂĄci jsou podrobnÄ pĆedstaveny nejdĆŻleĆŸitÄjĆĄĂ charakteristiky nekonvenÄnĂch technik CMOS. Tyto techniky byly pouĆŸity pro vytvoĆenĂ nĂzko napÄĆ„ovĂœch a nĂzko vĂœkonovĂœch CMOS struktur u nÄkterĂœch aktivnĂch prvkĆŻ, napĆ. Operational Transconductance Amplifier (OTA) zaloĆŸenĂ© na BD, FG, QFG, a BD-QFG techniky; Tunable Transconductor zaloĆŸenĂœ na BD MOST; Current Conveyor Transconductance Amplifier (CCTA) zaloĆŸenĂœ na BD-QFG MOST; Z Copy-Current Controlled-Current Differencing Buffered Amplifier (ZC-CC-CDBA) zaloĆŸenĂœ na BD MOST; Winner Take All (WTA) and Loser Take All (LTA) zaloĆŸenĂœ na BD MOST; Fully Balanced Four-Terminal Floating Nullor (FBFTFN) zaloĆŸenĂœ na BD-QFG technice. Za ĂșÄelem ovÄĆenĂ funkÄnosti vĂœĆĄe zmĂnÄnĂœch struktur, byly tyto struktury pouĆŸity v nÄkolika aplikacĂch. VĂœkon navrĆŸenĂœch aktivnĂch prvkĆŻ a pĆĂkladech aplikacĂ je ovÄĆovĂĄn prostĆednictvĂm simulaÄnĂch programĆŻ PSpice Äi Cadence za pouĆŸitĂ technologie 0.18 m CMOS.This doctoral thesis deals with designing ultra-low-voltage (LV) low-power (LP) analog circuits utilizing the unconventional CMOS techniques. Battery powered medical devices such as; long term physiological monitoring, portable, implantable, and wearable systems need to be small and lightweight. Besides, long life battery is essential need for these devices. Thus, low-power integrated circuits are always paramount in such biomedical applications. Recently, unconventional CMOS techniques i.e. Bulk-Driven (BD), Floating-Gate (FG), Quasi-Floating-Gate (QFG), Bulk-Driven Floating-Gate (BD-FG) and Bulk-Driven Quasi-Floating-Gate (BD-QFG) MOS transistors (MOSTs) have revealed as effective devices to reduce the circuit complexity and push the voltage supply of the circuit towards threshold voltage of the MOST. In this work, the most important features of the unconventional CMOS techniques are discussed in details. These techniques have been utilized to perform ultra-LV LP CMOS structures of several active elements i.e. Operational Transconductance Amplifier (OTA) based on BD, FG, QFG, and BD-QFG techniques; Tunable Transconductor based on BD MOST; Current Conveyor Transconductance Amplifier (CCTA) based on BD-QFG MOST; Z Copy-Current Controlled-Current Differencing Buffered Amplifier (ZC-CC-CDBA) based on BD MOST; Winner Take All (WTA) and Loser Take All (LTA) based on BD MOST; Fully Balanced Four-Terminal Floating Nullor (FBFTFN) based on BD-QFG technique. Moreover, to verify the workability of the proposed structures, they were employed in several applications. The performance of the proposed active elements and their applications were investigated through PSpice or Cadence simulation program using 0.18 m CMOS technology.
Low-power Wearable Healthcare Sensors
Advances in technology have produced a range of on-body sensors and smartwatches that can be used to monitor a wearerâs health with the objective to keep the user healthy. However, the real potential of such devices not only lies in monitoring but also in interactive communication with expert-system-based cloud services to offer personalized and real-time healthcare advice that will enable the user to manage their health and, over time, to reduce expensive hospital admissions. To meet this goal, the research challenges for the next generation of wearable healthcare devices include the need to offer a wide range of sensing, computing, communication, and humanâcomputer interaction methods, all within a tiny device with limited resources and electrical power. This Special Issue presents a collection of six papers on a wide range of research developments that highlight the specific challenges in creating the next generation of low-power wearable healthcare sensors
CMOS Design of Reconfigurable SoC Systems for Impedance Sensor Devices
La rĂĄpida evoluciĂłn en el campo de los sensores inteligentes, junto con los avances en las tecnologĂas de la computaciĂłn y la comunicaciĂłn, estĂĄ revolucionando la forma en que recopilamos y analizamos datos del mundo fĂsico para tomar decisiones, facilitando nuevas soluciones que desempeñan tareas que antes eran inconcebibles de lograr.La inclusiĂłn en un mismo dado de silicio de todos los elementos necesarios para un proceso de monitorizaciĂłn y actuaciĂłn ha sido posible gracias a los avances en micro (y nano) electrĂłnica. Al mismo tiempo, la evoluciĂłn de las tecnologĂas de procesamiento y micromecanizado de superficies de silicio y otros materiales complementarios ha dado lugar al desarrollo de sensores integrados compatibles con CMOS, lo que permite la implementaciĂłn de matrices de sensores de alta densidad. AsĂ, la combinaciĂłn de un sistema de adquisiciĂłn basado en sensores on-Chip, junto con un microprocesador como nĂșcleo digital donde se puede ejecutar la digitalizaciĂłn de señales, el procesamiento y la comunicaciĂłn de datos proporciona caracterĂsticas adicionales como reducciĂłn del coste, compacidad, portabilidad, alimentaciĂłn por baterĂa, facilidad de uso e intercambio inteligente de datos, aumentando su potencial nĂșmero de aplicaciones.Esta tesis pretende profundizar en el diseño de un sistema portĂĄtil de mediciĂłn de espectroscopĂa de impedancia de baja potencia operado por baterĂa, basado en tecnologĂas microelectrĂłnicas CMOS, que pueda integrarse con el sensor, proporcionando una implementaciĂłn paralelizable sin incrementar significativamente el tamaño o el consumo, pero manteniendo las principales caracterĂsticas de fiabilidad y sensibilidad de un instrumento de laboratorio. Esto requiere el diseño tanto de la etapa de gestiĂłn de la energĂa como de las diferentes celdas que conforman la interfaz, que habrĂĄn de satisfacer los requisitos de un alto rendimiento a la par que las exigentes restricciones de tamaño mĂnimo y bajo consumo requeridas en la monitorizaciĂłn portĂĄtil, caracterĂsticas que son aĂșn mĂĄs crĂticas al considerar la tendencia actual hacia matrices de sensores.A nivel de celdas, se proponen diferentes circuitos en un proceso CMOS de 180 nm: un regulador de baja caĂda de voltaje como unidad de gestiĂłn de energĂa, que proporciona una alimentaciĂłn de 1.8 V estable, de bajo ruido, precisa e independiente de la carga para todo el sistema; amplificadores de instrumentaciĂłn con una aproximaciĂłn completamente diferencial, que incluyen una etapa de entrada de voltaje/corriente configurable, ganancia programable y ancho de banda ajustable, tanto en la frecuencia de corte baja como alta; un multiplicador para conformar la demodulaciĂłn dual, que estĂĄ embebido en el amplificador para optimizar consumo y ĂĄrea; y filtros pasa baja totalmente integrados, que actĂșan como extractores de magnitud de DC, con frecuencias de corte ajustables desde sub-Hz hasta cientos de Hz.<br /
Design and implementation of a multi-modal sensor with on-chip security
With the advancement of technology, wearable devices for fitness tracking, patient monitoring, diagnosis, and disease prevention are finding ways to be woven into modern world reality. CMOS sensors are known to be compact, with low power consumption, making them an inseparable part of wireless medical applications and Internet of Things (IoT). Digital/semi-digital output, by the translation of transmitting data into the frequency domain, takes advantages of both the analog and digital world. However, one of the most critical measures of communication, security, is ignored and not considered for fabrication of an integrated chip. With the advancement of Moore\u27s law and the possibility of having a higher number of transistors and more complex circuits, the feasibility of having on-chip security measures is drawing more attention. One of the fundamental means of secure communication is real-time encryption. Encryption/ciphering occurs when we encode a signal or data, and prevents unauthorized parties from reading or understanding this information. Encryption is the process of transmitting sensitive data securely and with privacy. This measure of security is essential since in biomedical devices, the attacker/hacker can endanger users of IoT or wearable sensors (e.g. attacks at implanted biosensors can cause fatal harm to the user). This work develops 1) A low power and compact multi-modal sensor that can measure temperature and impedance with a quasi-digital output and 2) a low power on-chip signal cipher for real-time data transfer
Interface Circuits for Microsensor Integrated Systems
ca. 200 words; this text will present the book in all promotional forms (e.g. flyers). Please describe the book in straightforward and consumer-friendly terms. [Recent advances in sensing technologies, especially those for Microsensor Integrated Systems, have led to several new commercial applications. Among these, low voltage and low power circuit architectures have gained growing attention, being suitable for portable long battery life devices. The aim is to improve the performances of actual interface circuits and systems, both in terms of voltage mode and current mode, in order to overcome the potential problems due to technology scaling and different technology integrations. Related problems, especially those concerning parasitics, lead to a severe interface design attention, especially concerning the analog front-end and novel and smart architecture must be explored and tested, both at simulation and prototype level. Moreover, the growing demand for autonomous systems gets even harder the interface design due to the need of energy-aware cost-effective circuit interfaces integrating, where possible, energy harvesting solutions. The objective of this Special Issue is to explore the potential solutions to overcome actual limitations in sensor interface circuits and systems, especially those for low voltage and low power Microsensor Integrated Systems. The present Special Issue aims to present and highlight the advances and the latest novel and emergent results on this topic, showing best practices, implementations and applications. The Guest Editors invite to submit original research contributions dealing with sensor interfacing related to this specific topic. Additionally, application oriented and review papers are encouraged.
Electronics for Sensors
The aim of this Special Issue is to explore new advanced solutions in electronic systems and interfaces to be employed in sensors, describing best practices, implementations, and applications. The selected papers in particular concern photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs) interfaces and applications, techniques for monitoring radiation levels, electronics for biomedical applications, design and applications of time-to-digital converters, interfaces for image sensors, and general-purpose theory and topologies for electronic interfaces