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Logic Devices (logic + device)

Distribution by Scientific Domains
Polymers and Materials Science57%

Selected Abstracts

Learning computer architecture concepts with the FPGA-based "Move" microprocessor

COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2006
Veselko Gu
Abstract In this article we introduce the use of a programmable logic device (PLD) in an application-oriented study as an example of designing a microprocessor based on reduced instruction set computer (RISC) architecture. Since the concept of an in-system configurable logic circuit is becoming increasingly popular, we now use it for the purpose of logic design. We suggest that students use PLDs when constructing a central processing unit (CPU) with their own configured functions that are directly implemented in the logic. Such an approach could greatly increase the understanding of the architectural concept of the CPU. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 135,141, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20072 [source]

A pulse programmer for nuclear magnetic resonance spectrometers

CONCEPTS IN MAGNETIC RESONANCE, Issue 2 2007
C.C. Odebrecht
Abstract A pulse programmer (PP) designed to control a nuclear magnetic resonance (NMR) spectrometer is reported on. The heart of the PP is a computer programmable logic device (CPDL) that provides flexibility to the design and, at the same time, reduces the number of electronics components needed and the dimensions of the printed circuit board. The PP works as follow: first, a pulse sequence defined by a set of instructions is loaded into the RAM memory of the PP. Then, when the process is started, the instructions are, one by one, read, decoded, and executed. Four types of instructions (functions) were defined: PRINT A, PRINT B, WAIT, and STOP. PRINT A and PRINT B change the status of the output channels A and B, respectively, WAIT generates a time delay, and STOP terminates the sequence. The output ports A and B have 14 channels each, and the shortest pulse and resolution are both 200 ns. The design of the PP is versatile, and new functions can be added through software without modifying the printed circuit board. To control the PP from a personal computer, a program named PulseJr was developed. It contains a graphical user interface (GUI) and pulse sequences can be drawn on the monitor screen with the mouse of the computer. Once the pulse sequence is sketched, clicking a button the program compiles the pulse sequence, generates the set of instructions, loads them into the RAM memory of the PP, and starts the pulse sequence. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 127,131, 2007. [source]

Thin-Film Transistors: Transparent Photo-Stable Complementary Inverter with an Organic/Inorganic Nanohybrid Dielectric Layer (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 5 2009
Mater.
On page 726, Minsuk Oh and co-workers describe the fabrication of a transparent complementary thin-film transistor inverter with a ZnO top gate and bottom gate of pentacene channels. Twelve nanometer-thin organic,inorganic hybrid dielectric layers with high capacitance are adopted to allow the ZnO and pentacene transistors to operate under only 3 V, and the inverter action appears very stable even under a few mW of white light. This discovery could herald the arrival of a new type of transparent logic device. [source]

Transparent Photo-Stable Complementary Inverter with an Organic/Inorganic Nanohybrid Dielectric Layer

ADVANCED FUNCTIONAL MATERIALS, Issue 5 2009
Min Suk Oh
Abstract Transparent electronics has been one of the key terminologies forecasting the ubiquitous technology era. Several researchers have thus extensively developed transparent oxide-based thin-film transistors (TFTs) on glass and plastic substrates. However, work in transparent electronics has been limited mostly to high-voltage devices operating at more than a few tens of volts, and has mainly focused on transparent display drivers. Low-voltage logic devices, such as transparent complementary inverters, operating in an electrically stable and photo-stable manner, are now very necessary to practically realize transparent electronics. Electrically stable dielectrics with high strength and high capacitance must also be proposed to support this mission, and simultaneously these dielectrics must be compatible with both n- and p-channel TFTs in device fabrication. Here, a nanohybrid dielectric layer that is composed of multiple units of inorganic oxide and organic self-assembled monolayer is proposel to support a transparent complementary TFT inverter operating at 3,V. [source]

Selective Patterned Growth of Single-Crystal Ag,TCNQ Nanowires for Devices by Vapor,Solid Chemical Reaction,

ADVANCED FUNCTIONAL MATERIALS, Issue 19 2008
Kai Xiao
Abstract We report the deterministic growth of individual single-crystal organic semiconductor nanowires of silver,tetracyanoquinodimethane (Ag,TCNQ) with high yield (>90%) by a vapor,solid chemical reaction process. Ag,metal films or patterned dots deposited onto substrates serve as chemical reaction centers and are completely consumed during the growth of the individual or multiple nanowires. Selective-area electron diffraction (SAED) revealed that the Ag,TCNQ nanowires grow preferentially along the strong ,,, stacking direction of Ag,TCNQ molecules. The vapor,solid chemical reaction process described here permits the growth of organic nanowires at lower temperatures than chemical vapor deposition (CVD) of inorganic nanowires. The single-crystal Ag,TCNQ nanowires are shown to act as memory switches with high on/off ratios, making them potentially useful in optical storage, ultrahigh-density nanoscale memory, and logic devices. [source]

Assembly of Nanoscale Organic Single-Crystal Cross-Wire Circuits

ADVANCED MATERIALS, Issue 42 2009
Qingxin Tang
Organic single-crystal transistors and circuits can be assembled by nanomechanical manipulation of nanowires of CuPc, F16CuPc, and SnO2:Sb. The crossed bar devices have low operational voltage, high mobility and are stable in air. They can be combined into circuits, providing varied functions including inverters and NOR and NAND logic gates, opening new opportunities for organic nanoelectronics and highly sophisticated integrated logic devices. [source]

Photosensitization and the Photocurrent Switching Effect in Nanocrystalline Titanium Dioxide Functionalized with Iron(II) Complexes: A Comparative Study

CHEMISTRY - A EUROPEAN JOURNAL, Issue 20 2007
Wojciech Macyk Dr.
Abstract Selected iron(II) complexes (ferrocene, ferrocenylboronic acid, hexacyanoferrate(II)) have been used as photosensitizers of titanium dioxide. Various types of electronic interactions between the surface complex and the semiconducting support are reflected in different yields of photocurrent generated upon visible-light irradiation and different efficiencies of the photosensitization effect. The studied systems, showing the photocurrent switching upon changes of electrode potential and energy of photons (the PEPS effect), are good models of simple photoelectrochemical logic devices. The mechanism of photosensitization and photocurrent switching is discussed with respect to the type of surface-complex,support interaction. Quantum-mechanical calculations support the proposed mechanisms. Wybrane kompleksy ,elaza(II) (ferrocen, kwas ferrocenyloboronowy i heksacyjano,elazian(II)) zosta,y u,yte jako fotosensybilizatory dwutlenku tytanu. Ró,ne typy oddzia,ywa, elektronowych pomi,dzy kompleksami powierzchniowymi a pod,o,em pó,przewodnikowym znajduj, odbicie w ró,nych wydajno,ciach generacji fotopr,du i ró,nym stopniu fotosensybilizacji materia,ów na ,wiat,o widzialne. Wszystkie badane uk,ady wykazuj, efekt fotoelektrochemicznego prze,,czenia fotopr,du na skutek zmian potencja,u fotoelektrody i zmian d,ugo,ci fali ,wiat,a padaj,cego (efekt PEPS), dlatego te, stanowi, bardzo dobre modele prostych prze,,czników fotoelektrochemicznych. Niniejsza praca szczegó,owo okre,la mechanizm fotosensybilizacji i prze,,czenia fotopr,du na podstawie analizy oddzia,ywa, pomi,dzy kompleksem a powierzchni, pó,przewodnika. Obliczenia kwantowo-mechaniczne potwierdzaj, postulowany mechanizm. [source]